Elzohry MRCP Questions - Previous examinations

She is also of relatively short stature compared to Answer & Comments Answer: 1- Turner's syndrome Although Turner's syndrome XO and Down's and Noonan's syndromes can be associated with

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Part 1

Khalid Yusuf El-Zohry Sohag Teaching Hospital - Egypt

elzohryxp@yahoo.com https://www.facebook.com/elzohryxp

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Contents

ةمدقم 8

Reference ranges 11

[ Q: 4183 ] PasTest Exam - 2 exam 13

[ Q: 4282 ] PasTest Exam - 2 Mock exam 56

[ Q: 4383 ] PasTest Exam - 2006 January 99

[ Q: 4589 ] PasTest Exam - 2006 May 171

[ Q: 4790 ] PasTest Exam - 2007 September 260

[ Q: 4992 ] PasTest Exam - 2008 September 353

[ Q: 5295 ] PasTest Exam - 2009 May 491

[ Q: 1777 ] MRCPass - 2010 January 539

[ Q: 1876 ] MRCPass - 2010 May 581

[ Q: 1976 ] MRCPass - 2010 September 619

[ Q: 2331 ] ReviseMRCP - 2010 September 661

[ Q: 2515 ] ReviseMRCP - 2011 January 745

[ Q: 2176 ] MRCPass - 2011 May 787

[ Q: 2702 ] ReviseMRCP - 2011 May 833

[ Q: 2275 ] MRCPass - 2011 September 873

[ Q: 3255 ] ReviseMRCP - 2012 May 1043

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Take the first step , and your mind will

mobilize all its forces to your aid

But

The first essential is that you begin

Once the battle is startled, all that is within and without you will come to your assistance

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ا ددد اقددد ددد ق ذه جدددح لقدددنأ لددددمث دددحل ددددمحلا

دددمعلا ،

، دددح دددل ددد ددد م دنهنددديف ذه جددد مته

ذه

دددد ل ددددول ددددحعجف

جل ددددعت ددددم دددد ل ن دددد ي اددددم ،

نمحددديملا قن ددديل تقدددا دددل ت ددددل ء ددد م دنهنددديف

نغلا ق ظء ددددم قدددنأ لا قدددنأ لا ري دددجت دددم لقدددنأ اًدهنددداا ددددقل

ددد ذ ددددء ،ت ،ددددص ا

ا ددد قددد دددم هن دددهء دددمعلا

ي دددولا ددد هلا ق ددد لا ددد دددهل ددد ه ذه ددددء ا دددل ،

ا معلا

.

ا ا ددد ددد يدددل ث قدددنأ لا اًاقدددي دددم دنهنددداه ذه ندددحمل

دددنتقنلا ادددمجلا ددد ذ ددد مج دددهجم ددد ،تلمودددلا دددم دددف ت ددديث ذاودددنم ددد ذ ددد ف ذه جددد مته ،أندددي نلا

.ةم نقلا

مق ولا نا ف دل /ج

منحعنلا ا جه نيم –

ا

-

قوم

https://www.facebook.com/elzohryxp

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اريثك مهنم تدفتساو تملعت نيذلاو يتذتاسأو يئلامز

ديسلا ضاير د ضاير Riyadh Shalabi

ريشب د يملح

سواه كلاب د Black House

Ayman Shahin

د

Heba Mohammed

د

Ậquắ Ḿariŋê

د

Faisal Hemeda د

Reem Ali

د

Aburas Ab

د Shiny Moon

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Reference ranges

Reference ranges vary according to individual labs

All values are for adults unless otherwise stated

Full blood count

Haemoglobin Men: 13.5-18 g/dl

Women: 11.5-16 g/dl

Mean cell volume 82-100 fl

Platelets 150-400 x 109/l

White blood cells 4-11 x 109/l|

Urea and electrolytes

Alanine transferase (ALT) 3-40 iu/l

Aspartate transaminase (AST) 3-30 iu/l

Alkaline phosphatase (ALP) 30-100 umol/l

Gamma glutamyl transferase (yGT) 8-60 u/l

Prothrombin time (PT) 10-14 secs

Activated partial thromboplastin time (APTT)

25-35 secs

Ferritin 20-230 ng/ml

Vitamin B12 200-900 ng/l Folate 3.0 nmol/l

Reticulocytes 0.5-1.5%

Other biochemistry

Calcium 2.1-2.6 mmol/l Phosphate 0.8-1.4 mmol/l CRP < 10 mg/l

Thyroid stimulating hormone (TSH) 0.5-5.5 mu/l

Free thyroxine (T4) 9-18 pmol/l Total thyroxine (T4) 70-140 nmol/l Amylase 70-300 u/l

Uric acid 0.18-0.48 mmol/l

Arterial blood gases

pH 7.35 - 7.45 pCO2 4.5 - 6.0 kPa

pO2 10 - 14 kPa

Lipids

Desirable lipid values depend on other risk factors for cardiovascular disease, below is just a guide:

Total cholesterol < 5 mmol/l Triglycerides < 2 mmol/l HDL cholesterol > 1 mmol/l LDL cholesterol < 3 mmol/l

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[ Q: 4183 ] PasTest Exam - 2 exam

Water excretion in the kidneys is

influenced by:

1- Proximal tubule

2- Vasopressin

3- Distal tubule

4- Ascending limb of loop of Henle

5- Integrity of collecting ducts

Answer & Comments

Answer: 2- Vasopressin

Regulation of water secretion is by the distal

tubule and the collecting ducts under the

influence of vasopressin The relative

hyperosmolality of the medulla is maintained

by a counter-current mechanism and is

responsible for the flux of water across the

renal tubule

A 20-year-old woman presents with

hypothyroidism On further questioning it

transpires she has primary amenorrhoea She

is also of relatively short stature compared to

Answer & Comments

Answer: 1- Turner's syndrome

Although Turner's syndrome (XO) and Down's

and Noonan's syndromes can be associated

with short stature and hypothyroidism, Down's

syndrome and Noonan's syndrome are not

associated with menstrual irregularities

Females with an extra X chromosome (XXX

syndrome) are usually tall, whereas individuals with achondroplasia are usually very short; neither condition has an increased incidence of hypothyroidism or menstrual irregularities The other typical features of Turner's syndrome are cardiac defects (eg coarctation

of the aorta), congenital lymphoedema, neck webbing, widely spaced nipples and cubitus valgus Noonan's syndrome is an autosomal-dominant condition (so it affects both sexes), and other typical features include pulmonary stenosis, neck webbing and low-set posteriorly rotated ears

[ Q: 4185 ] PasTest Exam - 2 exam You are reviewing a 54-year-old man with a phaeochromocytoma

Which of the following is a suitable adrenoreceptor antagonist for the presurgical management of his hypertension?

a-1- Phenoxybenzamine 2- Atenolol

3- Propanolol 4- Nebivolol 5- Salbutamol

Answer & Comments

Answer: 1- Phenoxybenzamine

Phenoxybenzamine is a powerful a -receptor antagonist used in the presurgical management of phaeochromocytoma Atenolol is a cardioselective b-receptor antagonist, but still has some b2-antagonism and is therefore contraindicated in asthma Nebivolol has a vasodilating action in addition

to b-blocking effects and may be associated with a lower incidence of erectile dysfunction compared with other b-blocking agents Salbutamol is a b2-agonist used in the treatment of asthma

Agonists potentiate the physiological effects of certain receptors, whereas antagonists block those effects Another example of antagonism

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is the leukotriene-receptor antagonists which

block the bronchoconstrictor response to

inhaled leukotrienes Competitive antagonists

bind to the site of action for the endogenous

receptor ligand and can be displaced, (eg

prazosin), whereas non-competitive

antagonists (eg phenoxybenzamine) cannot be

displaced or have their effects diminished by

an endogenous receptor ligand A partial

agonist (eg acebutolol) may exhibit strong

receptor-binding activity, but a limited

physiological response

A 52-year-old black woman comes to

you for another opinion regarding a history of

anaemia that has been unresponsive to oral

iron supplementation She sought your opinion

because her other physician was

recommending iron supplementation iv She

has been on nearly continuous iron

supplementation therapy ever since her

second child was born 23 years ago Over the

years she says her doctors have prescribed her

to take anywhere from one to three pills daily,

sometimes with vitamin C concomitantly

Although she has never needed a transfusion,

she says she has been told that her RBC count

has never completely normalized She is

otherwise healthy and has no unusual dietary

habits Her menstrual history reveals relatively

normal menstrual periods until about 3 years

ago, when she attained menopause The

patient believes that her mother was also iron

deficient Your physical exam is normal

Laboratory values show a haemoglobin of 10.6

g/dl; haematocrit, 33%; MCV, 70 fl; normal

white blood cell (WBC) with differential;

normal platelet count; serum iron, 70 mg/l;

iron-binding capacity, 255 mg/dl; and ferritin,

158 m g/l

Which is the most likely diagnosis?

1- Sickle cell disease

2- Haemoglobin C disease

3- Beta-thalassaemia major

4- Homozygous alpha-thalassaemia 5- Acquired alpha-thalassaemia myelodysplastic syndrome

Answer & Comments

Answer: 4- Homozygous alpha-thalassaemia

This history is suspicious of homozygous thalassaemia Deletion of two a-genes results

a-in mild to moderate microcytosis and mild anaemia, rarely with any progression or development of other signs or symptoms Alpha-thalassaemia is probably the most common haemoglobinopathy in the world and the combination of one-gene or two-gene a-thalassemia has an incidence of 20% or more among blacks It is often mistaken for iron deficiency anaemia and menstruating women with the condition are often treated for prolonged periods with iron supplementation because it is presumed that the mild microcytic anaemia is due to iron deficiency A haemoglobin electrophoresis is a useful test for b-thalassemia wherein one looks for increased levels of haemoglobin A2 and haemoglobin F However, haemoglobin electrophoresis is generally not helpful for the diagnosis of an a-thalassemia disorder Haemoglobin C disease has an autosomal recessive inheritance and is one of the "benign" haemoglobinopathies, presenting as haemolytic anaemia Sickle cell disease presents as chronic haemolytic anaemia and vaso-occlusive crisis

antiarrhythmic agents works primarily by its action on SA and AV nodes?

1- Amiodarone 2- Atenolol 3- Flecainide 4- Sotalol 5- Verapamil

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Answer & Comments

Answer: 5- Verapamil

Calcium-channel blockers act mainly on the

sinoatrial and atrioventricular nodes (direct

membrane effect), as these structures are

almost exclusively depolarised by the slow

calcium channels Flecainide binds to the

sodium channel and decreases the speed of

depolarisation (in other words, decreases

conduction velocity) Atenolol decreases

sympathetic tone Amiodarone and sotalol

increase the action-potential duration and

therefore the refractory periods They have

little effect on conduction velocity

A 57-year old woman who has just

had a renal transplant is being given

azathioprine

Which of the following statements best

describes the main mechanism of action of this

drug?

1- It blocks antibody formation

2- It reduces the production of cytokines

3- It suppresses lymphocyte numbers and

function

4- It interferes with T cell-macrophage

cooperation

5- It interferes with T-cell activation

mechanisms at an intracellular level

Answer & Comments

Answer: 3- It suppresses lymphocyte numbers

and function

Azathioprine acts to inhibit purine synthesis

necessary for the proliferation of cells,

especially leukocytes and lymphocytes

Corticosteroids interfere with T

cell-macrophage cooperation and impair

macrophage responses to cytokines

Ciclosporin and tacrolimus interfere with T-cell

activation mechanisms at an intracellular level

A nurse has a needlestick injury after taking blood from a patient known to

be HIV positive

What is the most appropriate immediate management after hand washing for 10 minutes?

1- Continue hand washing for a further 20 minutes

2- Antiretroviral therapy 3- Test for hepatitis B and C 4- Blood cultures

5- Broad spectrum antibiotics

Answer & Comments

Answer: 2- Antiretroviral therapy

Based on data from more than 3000 occupational exposures to HIV, the average risk

of HIV infection after needlestick injury or other percutaneous exposure was calculated

to be 0.3% (about 1 in 325) The risk following mucous membrane exposure has been estimated to be around 0.1% The risk of transmission is greatest for deep injuries; if there is visible blood on the device; during procedures involving direct cannulation of blood vessels; or if the source patient has advanced HIV disease A small retrospective case-control study demonstrated an 80% reduction in the likelihood of seroconversion in healthcare workers who took zidovudine soon after percutaneous exposure to HIV In view of the greater activity of antiretroviral drug combinations but without direct evidence, it is currently recommended that high-risk occupational exposures to HIV are treated as soon as possible with two nucleoside inhibitors and a protease inhibitor (such as zidovudine, lamivudine, and nelfinavir) for 1 month Nevirapine is not currently recommended in postexposure prophylaxis regimens because of

a relatively high rate of adverse reactions In the management of occupational exposure to

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HIV, a careful risk assessment should be done

and information provided

A 72-year-old man is admitted

unconscious He has a history of type-2

diabetes and is taking 10 mg of glibenclamide

Blood testing reveals a serum creatinine level

of 195 mmol/l and a blood glucose of 1.5

mmol/l

Which treatment regime would be a suitable

alternative therapy for his diabetes?

1- Metformin

2- Chlorpropamide

3- Pioglitazone

4- Metformin and insulin combination therapy

5- Pioglitazone and insulin combination

therapy

Answer & Comments

Answer: 3- Pioglitazone

Chlorpropamide and glibenclamide are

long-acting sulphonylureas, and as such are

contraindicated in the elderly and in those with

renal impairment because of the risk of

hypoglycaemia Metformin is contraindicated

in patients with renal impairment,

discontinuation is recommended when

creatinine levels are above 130 mmol/l in

women and 150 mmol/l in men For this reason

metformin and insulin combination therapy

could equally not be a treatment option

Pioglitazone and insulin combination therapy is

currently contraindicated due to the risk of

oedema

This leaves pioglitazone as the most logical

treatment option Glitazones reduce

whole-body insulin resistance by increasing glucose

uptake into muscle and fat They are associated

with a low incidence of hypoglycaemia

A 25-year-old woman presents to a reproductive endocrinology clinic with a history of being unable to conceive after

2 years of using no contraception It is thought she may have polycystic ovarian syndrome

Which of the following is most likely to be associated with this condition?

1- A 28 day menstrual cycle 2- Elevated LH/FSH ratio 3- Normal free-androgen index 4- Low levels of circulating insulin 5- Normal BMI (body mass index)

Answer & Comments

Answer: 2- Elevated LH/FSH ratio

Polycystic ovarian syndrome is one of the commonest causes of anovulatory infertility Patients can have a normal menstrual cycle but are more likely to have oligomenorrhoea It is associated with a number of biochemical abnormalities, including raised LH levels, normal or elevated testosterone but with a low SHBG (sex-hormone-binding globulin) resulting

in a high free-androgen index Androstenedione levels can either be normal

or raised The underlying biochemical defect in patients with PCOS is recognised to be insulin resistance This causes high circulating insulin levels due to peripheral insulin resistance: therefore hyperinsulinaemia, and not low insulin levels, is characteristic of the condition The insulin resistance has been shown in both lean and obese patients with the condition

A 70-year-old-man reverts to atrial fibrillation after several attempts at cardioversion, but remains symptomatic despite rate control with digoxin and metoprolol He developed pulmonary fibrosis with amiodarone

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Which of the following will be the next step in

the management of this patient?

1- Switch metoprolol to amlodipine

2- Double the dose of digoxin

3- Radiofrequency pulmonary vein isolation

with ablation

4- Make another attempt at cardioversion

5- Implant a cardiovertor defibrillator

Answer & Comments

Answer: 3- Radiofrequency pulmonary vein

isolation with ablation

It is not always possible to restore and maintain

sinus rhythm in patients with AF If sinus

rhythm cannot be maintained, treatment

should be directed towards controlling the

heart rate with digoxin, β-blockers,

rate-limiting calcium-channel blockers (verapamil or

diltiazem) or amiodarone β-Blockers and

calcium-channel blockers are often more

effective than digoxin at controlling the heart

rate during exercise For patients who remain

poorly controlled despite medical therapy,

radiofrequency pulmonary vein isolation with

ablation is now seen as the treatment of choice

for atrial fibrillation cessation

A 30-year-old man presents with

frank haematuria and haemoptysis A blood

test shows microcytic hypochromic anaemia

Chest X-ray reveals bilateral infiltrates in the

lower zones

What is the most likely diagnosis?

1- Renal cell carcinoma

2- Renal calculus

3- Bronchial carcinoma

4- Renal tuberculosis

5- Goodpasture's syndrome

Answer & Comments

Answer: 5- Goodpasture's syndrome

This man most probably has Goodpasture's syndrome The disease often starts with an upper respiratory tract infection followed by cough and intermittent haemoptysis, tiredness and eventually anaemia Chest X-ray shadows are usually due to intrapulmonary haemorrhage These features usually precede the development of an acute glomerulonephritis by several weeks or months

Renal cell carcinoma rarely presents before the age of 40 years, the average age of presentation being 55 years Patients present with a classic triad of haematuria, loin pain and

a mass in the flank Malaise, anorexia and weight loss may occur, and one-third of patients have hypertension Bony metastases are common in bronchial carcinoma There is frequent involvement of the liver Although deposits are frequently found in the adrenal glands, the kidneys are seldom involved Tuberculosis of the urinary tract may present with frequency, dysuria and/or haematuria Adult postprimary pulmonary tuberculosis presents with a gradual onset of tiredness, malaise, anorexia, loss of weight, fever and cough Sputum may be mucoid, purulent or bloodstained The chest X-ray typically shows patchy or nodular shadows in the upper zones, loss of volume and fibrosis, with or without cavitation Calcification may be present

A 27-year-old woman known to suffer from epilepsy has been admitted with a history

of dizzy spells and a swollen left calf Her blood pressure recordings confirm a postural drop in her systolic reading of over 20 mmHg Her biochemistry shows a sodium concentration of

126 mmol/l and a potassium concentration of 6.1 mmol/l Her blood count is normal apart from a low platelet count She has no past

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history of any surgical procedure but has a

history of three spontaneous miscarriages The

nurse has noticed that at times she makes jerky

explosive movements of her limbs

What is the underlying diagnosis?

Answer & Comments

Answer: 3- Antiphospholipid syndrome

Antiphospholipid syndrome is characterised by

the presence of antiphospholipid antibodies,

which cause thrombosis through an effect on

platelet membranes, endothelial cells and on

prothrombin, protein C and protein S It is

characterised by recurrent abortions, epilepsy,

chorea, migraine and Addison's disease

On admission examination, a

60-year-old man is noted to have reduced facial

expression, rigidity and bradykinesia He has

been taking a long-term medication and a

diagnosis of early drug-induced Parkinsonism is

suspected

Which of the following treatments would be the

most likely cause?

A 29-year-old woman returns from a trip to the jungles of northern Thailand with bodyache, severe myalgia and a rash which began on her limbs and has now spread to involve the trunk She has fevers and night sweats which appear to return every 2 days Malaria films are negative

What diagnosis fits best with this clinical picture?

1- Dengue fever 2- Malaria 3- Hepatitis A 4- Influenza 5- Yellow fever

Answer & Comments

Answer: 1- Dengue fever

Dengue is the commonest arthropod borne viral infection in humans with 50-100 million cases occurring every year in the tropics and around 10 000 deaths per year from Dengue haemorrhagic fever It is caused by a flavivirus and is reported mainly in Asia, South-America and Africa The disease is transmitted by the daytime feeding mosquito, A aegypti Humans themselves are also infective during the first 3 days of the illness Classic dengue fever is characterised by abrupt onset of fever, malaise, headache, facial flushing, severe muscular backache and conjunctival suffusion

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Lymphadenopathy, petechiae on the soft

palate and a morbilliform rash which begins on

the limbs and later spreads to the trunk may

also occur Cough is uncommon The fever

subsides after 3-4 days and then returns in

cycles with a 48 h gap between each one

Successive cycles of fever and myalgia are

usually less severe Dengue haemorrhagic

fever is a much more severe form of the

disease, thought to be due to sequential

infection with different dengue sub-types

Diagnosis is usually via complement techniques

or enzyme-linked immunosorbent assay

(ELISA), and treatment is supportive

worsening back pain She also feels generally

weak An X-ray of her back shows multiple

vertebral collapses and lytic lesions

1- Osteoporosis

2- Osteosarcoma

3- Bone metastases

4- Multiple myeloma

5- Chronic myeloblastic leukaemia

Answer & Comments

Answer: 4- Multiple myeloma

Bone pain, frequently in the back or chest, is

present at diagnosis in more than two-thirds of

patients with myeloma Loss of height from

multiple vertebral collapses may occur The

most common symptoms are weakness and

fatigue, which are often due to anaemia Fever

is rare and, when present, is usually due to an

infection An acute infection, renal failure,

hypercalcaemia or amyloidosis may be the

presenting feature The liver is palpable in

about 20% of patients, and the spleen in 5%

Extramedullary plasmacytomas are uncommon

and are usually observed late in the course of

the disease as large, purplish, subcutaneous masses

A 56-year-old patient on gliclazide for his type-2 diabetes presents with an acute, central, crushing chest pain He is diagnosed with myocardial infarction

Which of the following best fits the outcome or management of myocardial infarction associated with type-2 diabetes?

1- The mortality rate from myocardial infarction in patients with type-2 diabetes is the same as that for non-diabetics

2- Intravenous insulin followed by sc insulin after MI reduces mortality by 11% at 3.5 years compared to controls

3- Use of ACE inhibition after MI improves the 6-week mortality rate by 50%

4- Statins should always be started unless they are contra-indicated

5- Blood pressure target should be 150/80 mmHg

Answer & Comments

Answer: 4- Statins should always be started

unless they are contra-indicated Diabetics may be up to twice as likely to die from myocardial infarction as non-diabetics, and are more likely to suffer an MI in the first place The DIGAMI study used iv insulin for 24

h followed by sc insulin for patients who had suffered an MI Risk reductions equalled 7.5%

at 1 year and 11% at 3.5 years compared to controls There is now significant doubt about this result as the study was repeated in the DIGAMI-2 study This showed no advantage in terms of cardiac outcomes for patients treated for a prolonged period with insulin Use of ACE inhibitors (GISSI-3 Diabetic Subgroup Study) is associated with a 30% relative-risk reduction in the 6-week mortality rate (8.7% vs 12.4%) Blood pressure reduction should be

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aggressively targeted, aiming for 130/80

mmHg, and all patients with diabetes who are

over 40 years of age should be started on statin

treatment unless there is a contraindication,

(Joint British Societies Guidelines)

A 56-year-old, highly insulin resistant,

type-2 diabetes sufferer has been taking 200

units total daily dose of sc insulin per day His

weight is increasing and his control worsening,

with an Hb A1C of 9.1% You add in pioglitazone

30 mg to his insulin Some 4 weeks later he

presents to the emergency department in

heart failure

Which of the following statements best

describes glitazone therapy?

1- Glitazones cause heart failure by exerting a

directly toxic effect on the myocardium

2- Glitazones have no more peripheral

insulin-sensitising effects than metformin

3- There is evidence that all three agents in the

glitazone class (troglitazone, pioglitazone

and rosiglitazone) have similar profiles of

hepatotoxicity

4- Heart failure may be precipitated in some

patients taking glitazones due to fluid

retention

5- Glitazones act at the site of the PPAR-a

receptor

Answer & Comments

Answer: 4- Heart failure may be precipitated in

some patients taking glitazones due to fluid

retention

There are currently two licensed glitazones

(insulin sensitisers) world-wide, rosiglitazone

and pioglitazone Both drugs act at the site of

the PPAR-g receptor, promoting the

transcription of genes predominantly linked to

fatty acid metabolism Fibrates, and some

newer dual agonists currently in development,

have activity at the PPAR-a receptor site Fluid

retention may be precipitated by these drugs, which may (in less than 1% of users) precipitate heart failure Experimental evidence has demonstrated that these drugs actually improve myocardial blood flow and glucose utilisation Metformin acts primarily by affecting hepatic insulin resistance, whereas the glitazones act by improving insulin sensitivity and peripheral glucose uptake in skeletal muscle and fat Troglitazone has been withdrawn due to liver side-effects

An 82-year-old man is reviewed in a medical clinic for weight loss and headaches

He has had trouble reading and there are no other neurological symptoms He is an ex-smoker and has cardiac failure controlled with furosemide (frusemide) and captopril On examination, he has axillary lymphadenopathy and splenomegaly FBC shows Hb 10.1 g/dl, WCC 6.2 x 103/mm3, platelets 118 x 103/mm3, ESR 98, and his renal and bone profiles are normal

What is the likely diagnosis?

1- Multiple myeloma 2- Temporal arteritis 3- Hodgkin's lymphoma 4- Lymphoplasmacytoid lymphoma 5- Systemic lupus erythematosus (SLE)

Answer & Comments

Answer: 4- Lymphoplasmacytoid lymphoma

This man has symptoms of hyperviscosity (headaches and visual disturbance) with a high ESR and lymph node enlargement Lymphoplasmacytoid lymphoma (or Waldenstrom's macroglobulinaemia) is due to infiltration of the marrow and reticular system with lymphoplasmacytoid cells that secrete IgM, which accumulates in the serum and, as it forms a pentamer in solution, increases the viscosity of the blood Myeloma can present

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with hyperviscosity, but this is rarer as the

immunoglobulin subclasses are G, A and D;

these form smaller molecules, and myeloma

does not tend to present with lymph node and

spleen enlargement Hodgkin's lymphoma can

present with weight loss and adenopathy with

a raised ESR, but not with hyperviscosity

Temporal arteritis can present with visual

disturbance and headache and raised

inflammatory markers, but is not associated

with adenopathy and splenomegaly

A 70-year-old woman is admitted to

hospital with a swollen left leg 4 weeks after

undergoing an elective total hip replacement

An above-knee DVT is diagnosed by

ultrasound She is in sinus rhythm at 60 bpm

and her blood pressure is 160/80 mmHg She is

commenced on the appropriate dose of low

molecular weight heparin and warfarin

loading The following day she becomes

acutely short of breath Examination reveals a

resting tachycardia (110 bpm) with blood

pressure of 100/60 mmHg Her JVP is elevated

at 7 cm above the sternal notch Arterial blood

gas measurement reveals her to be

hypoxaemic with a pa(O2 ) of 7 mmHg

What would be the first-line therapy after

administering high-flow oxygen?

1- Aspirin

2- Intravenous heparin

3- Surgical embolectomy

4- Thrombolysis with reteplase

5- Vena caval filter

Answer & Comments

Answer: 4- Thrombolysis with reteplase

This patient has clinical features of a massive

pulmonary embolus This results from

significant obstruction of the pulmonary

arteries causing haemodynamic compromise -

namely shock or systemic hypotension (systolic

blood pressure < 90 mmHg or a drop of > 40 mmHg for > 15 minutes) The initial treatment

of choice is thrombolysis using a recognised protocol Whilst she is only 4 weeks out from her hip replacement, the benefits fo thrombolysis would outweigh the risks in this case Inotropic support and the judicious use of fluids may also be required in the interim Subsequent intravenous unfractionated heparin should then be commenced

A 45-year-old woman who works in a pharmacy presents with episodes of tiredness and lethargy Her blood pressure is 115/75 mmHg Her bloods reveal hypokalaemia and a raised serum bicarbonate level Urine collection reveals hypercalciuria Otherwise the findings are unremarkable

What is the likely diagnosis?

1- Bartter's syndrome 2- Gitelman's syndrome 3- Frusemide abuse 4- Conn's syndrome 5- Liddle's syndrome

Answer & Comments

Answer: 3- Frusemide abuse

This picture could fit Bartter's syndrome, although Bartter's syndrome is rare (1 per million), has an autosomal-recessive pattern of inheritance and commonly presents below the age of 5 years Features of Bartter's syndrome include volume depletion, seizures, tetany and muscle weakness This woman's occupation is the clue, which unfortunately makes frusemide abuse very much more likely

A 35-year-old man has developed an itchy rash on his back and buttocks over the last

4 weeks Examination shows erythematous

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plaques with crusts and marks of excoriation

over his elbows, buttocks and back Apart from

well-controlled asthma, this patient has no

other medical history

Which of the following investigations, if

performed, would be most likely to be

Answer & Comments

Answer: 3- Small-bowel biopsy

The diagnosis is dermatitis herpetiformis (DH)

This is an extremely itchy condition associated

with a gluten-sensitive enteropathy (GSE) The

GSE does not cause symptoms in most DH

patients: less than 10% exhibit symptoms of

bloating, diarrhoea, or malabsorption

However, greater than 90% show

abnormalities upon endoscopic examination

Two thirds have villous atrophy detected on

intestinal biopsy specimens The other third

show elevated intraepithelial lymphocyte

counts, increased T-cell receptor gamma/delta

intraepithelial lymphocyte counts, or both

(This explains the correct answer here of small

bowel biopsy; however this test is not routinely

indicated for diagnosis of DH unless GI

symptoms are present) Patients present with

an erythematous rash on the extensor surfaces

(elbows, buttocks, shoulders and scalp)

Vesicles or crusts may be present and mucous

membranes may occasionally be affected Skin

biopsy shows IgA deposits in the unaffected

skin on immunofluorescence Gastrointestinal

symptoms are rare and treatment is with

dapsone and a gluten-free diet

A 56-year-old man complains of diarrhoea, abdominal pain, weight loss and joint pains, with 2 or 3 pale, bulky stools daily A jejunal biopsy shows stunted villi, and electron microscopy shows bacilli within the macrophages

What is the best treatment?

1- Gluten-free diet 2- Anti-TB treatment 3- Amoxicillin 4- Low-fat diet 5- Metronidazole

Answer & Comments

Answer: 3- Amoxicillin

This patient has Whipple's disease The causative organism is Tropheryma whippelli This can involve the heart, brain and lungs Possible choices for antibiotic therapy include amoxicillin, co-trimoxazole and chloramphenicol

Degranulation of eosinophils allows which of the following cellular processes?

1- Fusion of the lysosomal membrane with the plasma membrane

2- Chemotaxis 3- Ingestion within a phagosome 4- Intracellular enzymatic degradation 5- Endocytosis

Answer & Comments

Answer: 1- Fusion of the lysosomal membrane

with the plasma membrane Basophils, eosinophils and mast cells contain lysosomes and can release the contents of these granules by degranulation This allows them to act against larger infecting organisms

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such as protozoa and helminths, which cannot

be engulfed by phagocytosis Phagocytosis

comprises chemotaxis, ingestion within a

phagosome, intracellular enzymatic

degradation and exocytosis

Which one of the following intrinsic

hand muscles is supplied by the median nerve?

1- Lateral two interossei

2- Abductor pollicis brevis

3- Medial two lumbricales

4- Flexor pollicis longus

5- Extensor pollicis

Answer & Comments

Answer: 2- Abductor pollicis brevis

The median nerve supplies the following

structures in the hand:The abductor pollicis

brevis, flexor pollicis brevis, opponens pollicis

The lateral two lumbricales

The skin of the lateral three and half fingers

The flexor pollicis longus is also supplied by the

median nerve but is not one of the intrinsic

hand muscles, being located in the forearm

with its main action being thumb flexion The

ulnar nerve supplies all the interossei and the

rest of the hand muscles

An 82-year-old woman with atrial

fibrillation develops a sudden arterial occlusion

of her right arm due to a brachial embolism

Which statement pertaining to the arterial

system of the upper limb best accords with

usual clinical findings?

1- The brachial artery bifurcates into the ulnar

and radial arteries at the level of the head

Answer & Comments

Answer: 1- The brachial artery bifurcates into

the ulnar and radial arteries at the level of the head of the radius

The median nerve crosses from lateral to medial at the mid-humerus The artery is accompanied by two vena comitantes and gives off its profunda branch near the upper end of the humeral shaft, where it accompanies the radial nerve As with all joints, there is an excellent circulation around the elbow joint

A 25-year-old man is admitted to the A&E having consumed 20 tablets of propranolol An infusion of glucagon is prescribed

What is the main mechanism of action of glucagon in this case?

1- Promotes the formation of cyclic AMP 2- Stimulates lipolysis

3- Increases glycogenolysis 4- Promotes gluconeogenesis 5- Alters protein kinase A activity

Answer & Comments

Answer: 1- Promotes the formation of cyclic

AMP Glucagon acts by bypassing the blocked b-receptor, thus activating adenyl cyclase and

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promoting the formation of cyclic AMP from

ATP Cyclic AMP in turn exerts a direct

b-stimulant action on the heart Although all the

other options are actions of glucagon, they are,

however, not essential for reversing the effect

of excess propranolol ingestion

A patient is scheduled for an elective

All patients undergoing an elective

splenectomy should be immunised with

polyvalent pneumococcal vaccine

(Pneumovax), which currently gives variable

protection against 23 strains of Streptococcus

pneumoniae Where possible, it should be

given at least 2 weeks and preferably at least 4

weeks prior to splenectomy to allow

immunoglobulin G (IgG) antibody production

Cough as a side-effect of ACE

inhibitors occurs because of which of the

following?

1- ACE inhibitors cause dysgeusia

2- They cause bronchoconstriction

3- They affect the breakdown of bradykinin

within the lungs

4- ACE inhibitors increase bronchial mucous

secretion

5- They cause vasodilatation, which may result

in pulmonary congestion

Answer & Comments

Answer: 3- They affect the breakdown of

bradykinin within the lungs Dysgeusia (an unpleasant metallic taste) is a known side-effect of ACE inhibitors This side-effect is not responsible for the cough Coughing occurs because ACE inhibitors affect the breakdown of bradykinin in the lungs ACE inhibitors do not cause bronchoconstriction, pulmonary congestion or increase bronchial mucous secretion

A patient with diabetic retinopathy is treated with panretinal photocoagulation in the eye clinic and followed up in the diabetic clinic

Which of the following features found 6 months after treatment is an indication for further laser treatment?

1- Visual field constriction 2- Vitreous haemorrhage 3- Retinal burns

4- Optic atrophy 5- Tractional retinal detachment

Answer & Comments

Answer: 2- Vitreous haemorrhage

The source of the vitreous bleeding is likely to

be further growth of fragile neovascular tissue Options A, C, D and E are all possible sequelae

of laser treatment

A 16-year-old woman with Addison's disease is intolerant of her hydrocortisone treatment, which she takes at a dose of 20 mg

in the morning and 5 mg in the evening

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Which of the following doses of prednisolone

would provide an equivalent daily dose to her

Equivalent dose of prednisolone vs

hydrocortisone therapy is usually about 25% of

the hydrocortisone dose Adequacy of steroid

replacement is normally assessed by clinical

well being and restoration of normal (not

excessive) weight Cortisol levels during the

day are only a useful assessment if the patient

is on hydrocortisone Patients normally require

therapy with mineralocorticoids as well as

glucocorticoid therapy Standard therapy is

with fludrocortisone 50-300 mg/day, and

effectiveness is assessed by serum electrolytes,

postural change in blood pressure, and

suppression of plasma renin activity to normal

levels

You review a 72-year-old woman who

is complaining of severe nausea and lethargy

She has chronic atrial fibrillation for which she

takes digoxin 125m/day Her GP has recently

added a thiazide diuretic to her

antihypertensive regime Serum potassium

level is 3.0 mmol/l (3.5-4.9) Her pulse is 42

bpm, with a BP of 122/70 mmHg

What is the best course of action in this case?

1- Permanently stop her digoxin therapy

2- Administer FAB fragment antidigoxin

antibodies

3- Stop her thiazide diuretic and substitute

another antihypertensive agent

4- Introduce a small dose of spironolactone 5- Start potassium supplements but continue diuretic therapy

Answer & Comments

Answer: 3- Stop her thiazide diuretic and

substitute another antihypertensive agent

It is likely that the recent addition of the thiazide has precipitated a fall in her serum potassium concentration This has resulted in symptoms of digoxin toxicity with anorexia and nausea; often there is also altered vision Arrhythmias may occur: subtypes include ventricular premature beats, bigeminy, ventricular tachycardia and atrioventricular (AV) block In cases of digoxin toxicity, levels are usually above 2.5 nmol/l

Management includes restoration of serum potassium levels and symptomatic management of arrhythmias In cases of severe toxicity digoxin may be permanently stopped and another antiarrhythmic substituted if needed In this case there is no circulatory compromise, a temporary reduction/cessation

in digoxin therapy with correction of serum potassium is the best course of action

A 17-year-old adolescent complains

of intermittent face swelling It varies in severity but sometimes he has difficulty breathing His brother has similar symptoms

What protein is most likely to be responsible for his condition?

1- Interleukin-1 2- Interferon-gamma 3- Complement C3 4- C1 esterase inhibitor 5- Interleukin-6

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Answer & Comments

Answer: 4- C1 esterase inhibitor

Angioedema in the absence of urticaria is

caused by actual or functional C1 esterase

inhibitor deficiency This may be hereditary

with an autosomal-dominant mode of

inheritance, or acquired related to

lymphoproliferative disorders A family history,

the absence of pruritus, the prominence of

abdominal symptoms and recurrent attacks

suggest the hereditary cause C1 esterase

inhibitor concentrate or fresh-frozen plasma is

used to treat recalcitrant cases

A 72-year-old woman is admitted

with a sudden-onset, left-sided pleuritic chest

pain with shortness of breath She is being

treated for asthma, which has been well

controlled on a low dose of inhaled

corticosteroids and long-acting B-agonist She

underwent left hemiarthroplasty 12 days ago,

and was discharged as she was doing well Her

chest is clear on auscultation She is

tachycardic (132 beats/min) and an ECG shows

sinus tachycardia Her peak expiratory flow

(PEF) rate is 300 l/min (best 400 l/min) Arterial

blood gases are as follows: pH 7.34, pa(O2) 7.6

kPa, pa(CO2) 3.5 kPa She is started on oxygen

A chest radiograph is normal

What would be the most appropriate

immediate action taken by you as a medical

SHO?

1- Start nebulised bronchodilators and monitor

PEF rate

2- Request D-dimers urgently

3- Start low molecular weight heparin

suspecting PE, and request a V/Q scan

4- Start low molecular weight heparin

suspecting PE, and request CT pulmonary

angiography

5- Request a chest radiograph in expiration

Answer & Comments

Answer: 4- Start low molecular weight heparin

suspecting PE, and request CT pulmonary angiography

Her PEF rate is only mildly reduced (75% best)

It is unlikely that this patient's symptoms are due to an exacerbation of her asthma A small pneumothorax, not apparent on the inspiratory chest radiograph, is also unlikely since it would not cause marked hypoxia The symptoms and findings point towards a pulmonary embolism (PE), for which the clinical probability is high D-Dimers should not

be measured, since the result would not alter the need for definitive investigation: because she has had a recent operation it would be high anyway D-Dimers should only be measured when the probability of PE is low and further investigations would not be pursued.A V/Q scan is unlikely to be helpful in view of her asthma Therefore a CT pulmonary angiogram would be the imaging procedure of choice in this case, after starting low molecular weight heparin

A 27-year-old woman is in end-stage renal disease She has been started on regular haemodialysis She complains of pain in her fingers An X-ray shows digital subperiosteal erosions

What is the primary metabolic cause for her bony condition?

1- Increased serum phosphate levels 2- Increased parathyroid hormone levels 3- Increased renal 1a-hydroxylase enzyme levels

4- Increased serum calcium levels 5- Increased serum alkaline phosphatase levels

Answer & Comments

Answer: 1- Increased serum phosphate levels

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In renal failure, the stimuli for overproduction

of PTH are multifactorial Factors include

hypocalcaemia, impaired

1,25-dihydroxyvitamin D production by the diseased

kidneys, and hyperphosphataemia

Hyperphosphataemia appears to be

particularly important in the development of

parathyroid hyperplasia These stimuli cause

multigland hyperplasia, resulting in increased

PTH production Chronic overproduction of

PTH in patients with renal failure contributes to

the spectrum of bone disease observed in

patients on dialysis In most patients on

dialysis, the primary bone disease is osteitis

fibrosa cystica, a disease of increased bone

resorption caused by elevated PTH levels

Skeletal lesions include subperiosteal bone

erosions, usually observed best in the distal

phalanges

There is an outbreak of diarrhoea and

vomiting on an acute surgical ward, initially

affecting patients, but then rapidly also staff

What is the most likely agent?

There have been dramatic outbreaks of this

virus (also known as Norwalk-like virus, small

round-structured virus, SRSV) in UK hospitals in

2002/03 necessitating closure of wards

Transmission is by direct contact, but also

possibly by droplet spread The prodromal

illness can be minutes! Enteroviruses are so

called because they are replicate in the

gastrointestinal (GI) tract, but they only very

rarely give rise to GI symptoms

A 69-year-old man has diabetes, ischaemic heart disease and hypertension He has smoked 20 cigarettes a day for the last 43 years One morning his son contacts you because he is concerned about him During a telephone conversation, he reports that his father 'wasn't making sense' You see the father in your clinic He is orientated and alert, with normal power, tone and reflexes throughout Assessment of his speech reveals some difficulty with word identification and repetition He has difficulty naming examples within a category, e.g types

of animals He can follow instructions, however An MRI scan of the brain shows a small localised infarct

Where is this likely to be?

1- Posterior, superior temporal lobe (Wernicke's area)

2- Angular gyrus 3- Inferior frontal lobe (Broca's area) 4- Arcuate fasciculus

5- Medial superior temporal lobe

Answer & Comments

Answer: 3- Inferior frontal lobe (Broca's area)

Trauma, space-occupying lesions, strokes and surgery may produce very focal cortical lesions Language production involves many different areas of the brain acting in concert, and it is unusual to get a 'pure' speech disturbance of this kind Comprehension, fluency and repetition are the three main variables that allow for localisation of speech problems The three, general, areas are:Wernicke's area (posterior, superior temporal lobe) - lesions produce normal fluency, impaired

repetition.Conduction (arcuate fasciculus) - lesions produce normal fluency, normal comprehension, diminished repetition.Broca's area (inferior frontal lobe) - lesions produce

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impaired fluency, intact comprehension,

impaired repetition

painful swelling of her left arm Venography

shows occlusion of her left subclavian vein Her

only previous medical history is of three

spontaneous miscarriages Her haematological

investigations before treatment were as

follows:Hb 13.2 g/dl, WCC 7.4 x 109/L, with a

normal differential, platelets 123 x 109/L, PT 16

s (normal range 12-17), APTT 44 s (normal

range 24-38), TT 17 s (normal range 14-22) and

fibrinogen 2.4 g/l (normal range 2-5)

What is the most likely cause of her thrombotic

problem?

1- Factor V Leiden mutation

2- von Willebrand's disease

3- Primary thrombocythaemia

4- Antiphospholipid syndrome

5- Autoimmune thrombocytopenia

Answer & Comments

Answer: 4- Antiphospholipid syndrome

The antiphospholipid syndrome (APS) may be

diagnosed when arterial or venous thrombosis

or recurrent miscarriage occurs in a patient

with positive laboratory tests for

antiphospholipid antibody Patients may also

have thrombocytopenia and livedo reticularis,

but APS can be detected incidentally in healthy

subjects On laboratory screening the APTT is

prolonged and does not correct to normal

when mixed with normal plasma, showing the

presence of an inhibitor This can be confirmed

on further coagulation testing and

immunoassays for anticardiolipin antibodies

Patients require anticoagulation, the duration

and intensity of which depends on the clinical

scenario Antiphospholipid antibodies can also

be detected in association with certain drugs,

eg chlorpromazine, and with chronic infection,

eg syphilis and hepatitis C

A 23-year-old man who lives with his male partner consults you for an opinion He has suffered anal discharge and pruritis for the past 3 days There are also some symptoms of dysuria A urethral smear reveals intracellular diplococci

What is the most likely infective agent to fit with this clinical picture?

1- Neisseria gonorrhoeae 2- Chlamydia trachomatis 3- Treponema pallidum 4- Herpes simplex-type 1 5- Herpes simplex-type 2

Answer & Comments

Answer: 1- Neisseria gonorrhoeae

Gonorrhoea, a sexually transmitted bacterial infection, may manifest with urethritis, cervicitis, salpingitis or anorectal symptoms Symptoms in men may be severe and include purulent discharge from the anterior urethra and dysuria, with rectal discharge where anal intercourse has taken place Symptoms in women are often mild, with urethritis and cervicitis occurring a few days after exposure

In around 20% of cases, uterine invasion may occur with signs and symptoms of endometritis

or salpingitis Inflamed Bartholin's glands may occur

The cause is the Gram-negative intracellular diplococcus Neisseria gonorrhoeae Their presence is diagnostic in male urethral smears, although there is a false-negative rate of 60-70% in samples from women Gonococci require culture in anaerobic media in an increased carbon dioxide environment Patients should of course also receive screening for other sexually transmitted disease The treatment of choice is with

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quinolone antibiotics, but local protocols

should be referred to

You are asked to see a 25-year-old

White man who experienced marked weakness

and dyspnea 4 days after being admitted for a

compound arm fracture after falling from a

tree Estimated blood loss from the initial

fracture episode was 600 ml and the patient

was transfused with one unit of packed

erythrocytes The initial crossmatch was

reported as compatible by the transfusion

service The patient has never been transfused

before this incident and has no other serious

medical illnesses The patient's arm fracture

was treated with surgical pinning and

prophylactic antibiotics consisting of a

cephalosporin iv every 12 h On examination,

the patient is febrile and mildly tachycardic,

with no evidence of wound infection or

compartment syndrome Laboratory data

show a haematocrit of 15%, a raised

reticulocyte count and total bilirubin of 70

mol/l with a conjugated bilirubin of 9 moll/l

The peripheral smear shows many

spherocytes No haemoglobinaemia or

haemoglobinuria is seen on visual inspection of

the plasma and urine The transfusion service

reports that the direct Coombs' test is now

strongly positive using anti-IgG and only weakly

positive with anti-C3d antisera They further

report that routine compatibility tests show no

new erythrocyte antibodies in the patient's

serum and that, when they attempted to elute

antibody from the patient's RBCs and test

against normal RBCs, the results were negative

1- Haemolytic transfusion reaction caused by

an ABO incompatibility

2- Delayed haemolytic transfusion reaction

3- Autoimmune haemolytic anaemia of warm

antibody type

4- Autoimmune haemolytic anaemia of cold

antibody type

5- Drug-induced immune haemolytic anaemia

Answer & Comments

Answer: 5- Drug-induced immune haemolytic

anaemia Decreased haematocrit, raised reticulocyte count and raised unconjugated bilirubin all point towards a diagnosis of haemolytic anaemia Drug-induced immune haemolytic anaemia of the hapten type is recognised in patients exposed to high doses of penicillin Due to cross-reactivity, cephalosporins can also less commonly produce this type of reaction Other drugs that are associated with haemolytic anaemia include methyldopa, quinidine, quinine, chlorpromazine and the sulphonamides In this patient the strongly positive direct Coombs test shows that this is

an immune haemolytic anaemia Three findings suggest the diagnosis of a drug-induced mechanism rather than an autoimmune mechanism: (1) the patient received a cephalosporin known to induce a hapten-type reaction, (2) routine tests for RBC antibodies in the patient's serum were negative even though the patient's RBCs were strongly coated for antibody and (3) eluate from the patient's RBCs was not reactive with normal RBCs The anaemia should begin to improve after drug withdrawal

A 45-year-old woman has been on amiodarone for the past 3 years She now complains of lethargy, weight gain and depression

Which investigation would be most useful in this case?

1- Blood urea and electrolytes 2- Liver function tests

3- Full blood count 4- T3, T4 and TSH levels 5- ECG

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Answer & Comments

Answer: 4- T3, T4 and TSH levels

Amiodarone is a Class III antiarrhythmic drug

Its effects on the thyroid are variable It

commonly causes a rise in free T4 and a fall in

free T3 levels Some 2% of patients have

clinically significant changes - which may be

hyperthyroidism or hypothyroidism The

clinical state is more useful in monitoring

treatment than the tests As amiodarone has a

prolonged half-life, the problems may persist

for up to 3 months after withdrawal of the

drug

A 46-year-old man on haemodialysis

for 12 years complains of insidious onset of

painful nocturnal dysesthesias involving the

thumb and three fingers, relieved by shaking

the hand Physical examination of the hand

reveals thenar wasting and numbness over the

fingers

Which of the following statements fits best with

this clinical picture?

1- Deposition of amyloid of the AL (associated

with light chains) type would be likely

2- Carpal tunnel syndrome would explain these

findings

3- Deposits of b2-microglobulin-associated

amyloid are extremely unlikely to be a

contributory cause

4- These findings are most likely to be

associated with generalised peripheral

neuropathy

5- These symptoms suggest compression of the

ulnar nerve

Answer & Comments

Answer: 2- Carpal tunnel syndrome would

explain these findings

Clinically, the patient has carpal tunnel

syndrome, an entrapment neuropathy in which

the median nerve is compressed within the carpal tunnel area A new type of amyloid protein identified as b2-microglobulin has been demonstrated in bone and carpal tunnel tissue

of patients undergoing long-term (usually greater than 10 years) haemodialysis It is hoped that modifications of the dialysis membranes may result in improved b2-microglobulin clearance with diminished tissue deposition and switching to newer dialysis membranes may improve symptoms of b2-microglobulin deposition Carpal tunnel syndrome itself may be managed with surgical division of the flexor retinaculum, but unfortunately patients often present late, after

at least some nerve damage has become established

A 40-year-old woman was brought unconscious to the accident and emergency department On recovery she is found to have impaired visual acuity (RVA 6/24, LVA 6/36) Her blood pressure is 90/60 mmHg Her electrolytes are abnormal, with a sodium level

of 130.0 mmol/l and a potassium level of 6.5 mmol/l Her previous medical history includes amenorrhoea for the last 5 years

What treatment should be administered urgently?

1- Intravenous aciclovir 2- Intravenous cefuroxime 3- Intravenous hydrocortisone 4- Intravenous phenytoin 5- Intravenous thiamine

Answer & Comments

Answer: 3- Intravenous hydrocortisone

The most likely diagnosis is pituitary apoplexy The long history of amenorrhoea may indicate

a prolactinoma Her low blood pressure and abnormal electrolytes indicate that she needs

an urgent administration of steroids to prevent

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an addisonian crisis Pituitary apoplexy is due

to haemorrhage within an existing pituitary

adenoma and presents with altered

consciousness and visual disturbances CT

brain is usually diagnostic

Which one of the following

antiplatelet agents acts by inhibiting the

phosphodiesterase enzyme and increasing the

cellular concentration of cyclic adenosine

Dipyridamole is a weak antiplatelet agent that

acts by increasing the cellular concentration of

cyclic adenosine monophosphate (cAMP) It

inhibits the phosphodiesterase enzyme which

converts cyclic adenosine monophosphate

(cAMP) to inactive 5'AMP Elevated levels of

cAMP and cGMP inhibit activation and

aggregation of platelets Aspirin is a potent

inhibitor of platelet cyclo-oxygenase This is an

enzyme that converts arachidonic acid to

thromboxane A2 (TxA2), a strong platelet

agonist Because the platelet has no protein

synthetic apparatus the effects of aspirin are

irreversible and last for the life of the platelet

(8-10 days) The antiplatelet effect of

clopidogrel like ticlopidine, results from

antagonism of a platelet ADP receptor, P2T,

resulting in inhibition of platelet activation

This antagonism is non-competitive,

irreversible, and results in 50-70% inhibition of

fibrinogen binding

Regardless of the mechanism of activation, the

final common pathway for platelet aggregation

is the cross-linking of platelets through fibrinogen Abciximab is a humanized monoclonal antibody It is a selective GPIIb-IIIa receptor antagonist

A 20-year-old student presents with a 5-day history of fever and sore throat His GP started him on penicillin, but there was no improvement On examination his temperature is 38.8°C, he has grey plaques on his tonsils, cervical lymphadenopathy and splenomegaly

1- Streptococcus infection 2- Borrellia vincenti infection 3- Diphtheria

4- Infectious mononucleosis 5- Toxoplasmosis

Answer & Comments

Answer: 4- Infectious mononucleosis

Infectious mononucleosis is associated with kissing The disease is acquired when a healthy carrier, who is shedding virus in his/her saliva, passes it during close buccal contact directly into the oropharynx of a partner who was not primarily infected as a child However as the incubation period is 1-2 months, initial contact with an individual with pharyngitis may not be remembered Although most cases occur in adolescents and young adults, children and the middle-aged may sometimes develop the disease, and rarely also the elderly Primary Epstein-Barr virus (EBV) infection giving infectious mononucleosis-like symptoms may also be transmitted by blood transfusion or organ grafting from an infected donor to a previously uninfected recipient

Classic infectious mononucleosis may follow some days of vague indisposition or may start abruptly It presents with sore throat, fever with sweating, anorexia, headache and fatigue,

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together with malaise quite out of proportion

to the other complaints Dysphagia may be

noticed and also brief orbital oedema

Erythematous and maculopapular rashes occur

in a small number of untreated patients, but in

many more who have been taking ampicillin for

a sore throat before infectious mononucleosis

has been diagnosed Rarely, tonsillar and

pharyngeal oedema can cause pharyngeal

obstruction The fever may rise to 40°C but

high levels and swings are not seen There is

redness and oedema of the pharynx, fauces,

soft palate and uvula, and about half the

patients develop greyish exudates Generalised

lymphadenopathy is almost always present,

most marked in the cervical region; the glands

are symmetrical, discrete and slightly tender,

and are accompanied by splenomegaly in

about 60% of cases and an enlarged liver in

10% There is usually a moderate bradycardia

Besides the rash, characteristic palatal

enanthematous crops of reddish petechiae are

found in about one-third of patients, and

jaundice occurs in about 8%

Borrelia vincenti infection causes acute

necrotising ulcerative gingivitis

You review a 44-year-old woman in

an out-patient clinic following an urgent

referral from her GP She had recently been

started on hydralazine for blood pressure

management Since then she has developed

symptoms and signs suggestive of

drug-induced lupus

Which of the following statements is true

concerning drug-induced lupus disease?

1- It is more common in Caucasians than

Afro-Caribbeans

2- HLA-DR4 is not associated with it

3- Rapid acetylator status is a risk factor

4- dsDNA antibodies are positive

5- Antihistone antibody is negative

Answer & Comments

Answer: 1- It is more common in Caucasians

than Afro-Caribbeans Drug-induced lupus is more common in Caucasians, unlike idiopathic lupus, and the usual female predominance is lost Risk factors include HLA-DR4 phenotype (hydralazine-induced disease), slow acetylator status and large total daily doses of precipitating drugs Drugs commonly associated with drug-induced lupus include hydralazine, procainamide and isoniazid ANF (antinuclear factor) and antihistone antibodies are positive but dsDNA (double-stranded DNA) antibodies are negative The management of drug-induced lupus is withdrawal of the precipitating drug and supportive care; spontaneous recovery usually occurs promptly

A 48-year-old man is referred with impotence He has a history of angina, hypertension, and type-2 diabetes

Which one of the following drugs that he takes presents a contraindication to him being able

to receive sildenafil?

1- Aspirin 2- Bendroflumethazide 3- Isosorbide mononitrate 4- Lisinopril

5- Metformin

Answer & Comments

Answer: 3- Isosorbide mononitrate

Sildenafil is a phosphodiesterase (PDE-5) inhibitor indicated for the treatment of erectile dysfunction It is contraindicated in patients with proved coronary artery disease and in patients who are taking oral nitrate therapy Drugs such as isosorbide mononitrate, which

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increase nitric oxide availability, may

precipitate dangerous hypotension when

combined with PDE-5 inhibitors A common

side-effect of sildenafil includes headache,

predominantly through cerebral vasodilation

Alternatives to sildenafil in this patient may

include prostaglandins given via pessary or

injection into the penis; apomorphine may also

be considered as an alternative

A 39-year-old woman complains of

swelling, stiffness and pain in her fingers She

also tells her doctor that in winter her fingers

often turn dark in colour Her autoimmune

screen shows the presence of anticentromere

5- CREST variant of scleroderma

Answer & Comments

Answer: 5- CREST variant of scleroderma

Antibodies to centromere are a subset of

antinuclear antibodies, which most commonly

occur in the CREST variant of scleroderma

(CREST = calcinosis cutis-Raynaud's

phenomenon-oesophageal

hypomotility-sclerodactyly-telangiectasia) They are

uncommon in the diffuse form of scleroderma

They are rarely present in rheumatoid arthritis,

SLE and polyarteritis nodosa

A 39-year-old man notices that he

sustained a burn to his right hand while

cooking, without being aware of it On further

questioning he admits that his grip on the same

side has become gradually weaker over several months On examination he has wasting and weakness of the right intrinsic hand muscles, with occasional fasciculation seen in the abductor pollicis brevis There is sensory loss to pinprick and temperature over his right arm and trunk in a hemicape distribution He has a right Horner's syndrome His lower limbs have normal power but slightly increased tone, brisk reflexes and extensor plantar responses The remainder of the examination is normal

Which of the following is the most likely explanation for his symptoms and signs?

1- Syringomyelia 2- Meningioma of the cervical cord 3- Neurofibromas in the cervical cord and brachial plexus

4- Primary progressive multiple sclerosis 5- Motor neurone disease

Answer & Comments

Answer: 1- Syringomyelia

The combination of gradual spinothalamic sensory loss in the described distribution, Horner's syndrome, lower motor neurone signs

in the upper limb and upper motor neurone signs in the lower limbs, is highly suggestive of syringomyelia, an abnormal cavitation within the central cord This usually occurs in the cervical region but may extend upwards into the brainstem (syringobulbia) or downwards to the thoracic or even lumbar cord There may be associated craniovertebral abnormalities such

as a scoliosis or vertebral fusion, and about 90% of patients have a type-1 Chiari malformation (descent of the cerebellar tonsils into the foramen magnum) Treatment is neurosurgical

A 52-year-old Caucasian woman presents to her GP complaining of tiredness and itching She has no history of alcohol abuse

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and takes no medication She has xanthelasma

Her GP notices that her alkaline phosphatase

level is raised, and refers her for a

gastroenterological opinion

What would be the best investigation to

confirm a diagnosis of primary biliary cirrhosis?

1- Hepatic ultrasound scan

2- Bone scan

3- Alkaline phosphatase origin estimation

(bone or liver)

4- Anti-mitochondrial antibodies

5- GGT (gamma glutamyl transferase) testing

Answer & Comments

Answer: 4- Anti-mitochondrial antibodies

The history is highly suggestive of primary

biliary cirrhosis (PBC) In PBC,

anti-mitochondrial antibodies are found in 95% of

cases, and are said to be 98% specific for PBC

A liver biopsy will confirm the diagnosis PBC

occurs most frequently in women and who are

between the ages of 30 and 65 years Prognosis

is poor, ursodeoxycholic acid may have some

effect on prognosis and time to liver transplant

due to progressive cirrhosis Median survival in

symptomatic patients is 7 years from the time

of presentation, 10 years in patients who are

asymptomatic at the time of diagnosis

A 25-year-old man is admitted to the

A&E having consumed 20 tablets of

propranolol An infusion of glucagon is

prescribed

What is the main mechanism of action of

glucagon in this case?

1- Promotes the formation of cyclic AMP

2- Stimulates lipolysis

3- Increases glycogenolysis

4- Promotes gluconeogenesis

5- Alters protein kinase A activity

Answer & Comments

Answer: 1- Promotes the formation of cyclic

AMP Glucagon acts by bypassing the blocked b-receptor, thus activating adenyl cyclase and promoting the formation of cyclic AMP from ATP Cyclic AMP in turn exerts a direct b-stimulant action on the heart Although all the other options are actions of glucagon, they are, however, not essential for reversing the effect

of excess propranolol ingestion

A 37-year-old woman presents to the endocrine clinic with a history of hirsutism, acne and oligomenorrhoea She is having difficulty losing weight and has searched the Internet and thinks she may have polycystic ovarian syndrome She wants to discuss the implications of this

Which of the following is the most important issue to discuss with her at this stage of her life?

1- Exercise regimens 2- Does she want to have children 3- Her blood glucose level

4- Treatment for her hirsutism 5- Weight-reduction diets

Answer & Comments

Answer: 2- Does she want to have children

All the above are relevant and each should be discussed The hirsutism and acne can be very difficult to deal with and can cause distress from a cosmetic point of view There are a variety of treatment options but Dianette (cyproterone acetate) is probably the most effective, along with cosmetic treatments like waxing, shaving, plucking or electrolysis Her future risk of type-2 diabetes and associated cardiovascular risk is very important and she should be advised about the need for lifestyle treatments and the need to lose weight and

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exercise regularly to reduce the chance of this

happening It is now recommended that all

patients with PCOS have their fasting blood

glucose level measured annually to pick up

diabetes at an earlier stage However, the most

important issue in a woman of her age is

fertility, as women with PCOS frequently

require assistance with conception Her age is

against her if she is going to have problems

with fertility and requires help to conceive The

commonest treatment is to induce ovulation

with clomifene She needs to be advised that

pregnancy also carries an increased risk of

gestational diabetes

A 67-year-old woman is admitted

with iron-deficiency anaemia She has an

ejection systolic murmur radiating to both

carotids An upper GI endoscopy and

colonoscopy is normal

Which of the following is the most appropriate

next investigation?

1- Repeat upper GI endoscopy

2- Bone marrow examination

This woman presents with an iron-deficiency

anaemia and also has features of aortic

stenosis Her upper GI endoscopy and

colonoscopy are normal The most likely

diagnosis is angiodysplasia, and an angiogram

is the best next investigation Angiodysplasias

are associated with aortic stenosis

A 65-year-old man presents with

haematuria, right loin pain and night sweats

Physical examination reveals a mass in the right flank Blood tests show normocytic normochromic anaemia

1- Renal tract calculi 2- Adult polycystic kidney disease 3- Renal carcinoma

4- Renal amyloidosis 5- Chronic pyelonephritis

Answer & Comments

Answer: 3- Renal carcinoma

The average age of presentation of renal cell carcinoma is around 55 years Patients present with a classic triad of haematuria, loin pain and

a mass in the flank Malaise, anorexia and weight loss may occur and one-third of patients has hypertension

Pain in ureteric calculus, which is most often associated with haematuria, is extremely severe Night sweats do not occur in this condition Renal amyloidosis presents with asymptomatic proteinuria, nephritic syndrome

or renal failure Haematuria is not a feature Chronic pyelonephritis is also known as 'reflux nephropathy' This starts in infancy or early childhood, predisposes to recurrent infections and progressive renal fibrosis and loss of function The kidneys are small, shrunken and scarred Adult (autosomal-dominant) polycystic kidney disease is an inherited disorder usually presenting in adult life It is mostly bilateral and presents with acute loin pain and/or haematuria Night sweats are not characteristic of this disease

A 70-year-old man is admitted with pruritus, jaundice, and a 2 kg weight loss of duration two weeks He had not drunk any alcohol for at least eight years One month previously, he had completed a course of co-amoxiclav, which had been prescribed by his

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general practitioner for sinusitis, and was also

taking ibuprofen for hip osteoarthritis

Investigations reveal (normal range in

brackets):

Albumin 38 g/l (37-49)

Bilirubin 200 m mol/l (1-22)

Aspartate transaminase (AST) 150 IU/l (5-35)

Alkaline phosphatase 200 IU/l (50-110)

Abdominal ultrasound reveals gallstones, but

no biliary duct dilatation

What is the most likely cause of his jaundice?

Cholestatic jaundice may occur during

co-amoxiclav therapy or shortly afterwards

Epidemiological studies put the risk of acute

liver toxicity at about six times higher with

co-amoxiclav compared to amoxicillin therapy

alone Cholestatic jaundice occurs more

commonly in patients older than 65 years and

more commonly in men; these reactions are

rarer in children Jaundice is usually

self-limiting and rarely fatal Duration of

co-amoxiclav therapy should be appropriate to

the indication and not exceed 14 days on the

advice of the Committee on Safety of

Medicines Other, rarer side-effects of

co-amoxiclav include erythema multiforme, toxic

epidermal necrolysis, and exfoliative

dermatitis

You are asked to assess the

cardiovascular risk status of a man with the

insulin-resistance syndrome

Which of the following pathophysiological changes are most strongly associated with increased insulin resistance?

1- Hypotension 2- Increased levels of Plasminogen activator inhibitor-1 PAI-1

3- Decreased platelet aggregation 4- Improved endothelial function 5- Increased HDL levels

Answer & Comments

Answer: 2- Increased levels of Plasminogen

activator inhibitor-1 PAI-1 Put simply, increased insulin resistance in an individual means that they require higher circulating levels of insulin to deal with a given glucose load compared to a normal subject Increased insulin resistance is associated with the clinical insulin-resistance (metabolic) syndrome consisting of a number of features including abnormal glucose tolerance, hypertension, low HDL cholesterol and abdominal obesity In addition, there is an associated procoagulant state, with increased levels of plasminogen activator inhibitor (PAI-1), associated in clinical studies with an increased risk of myocardial infarction Insulin resistance is also associated with raised inflammatory markers such as monocyte chemoattractant protein-1 (MCP-1) and tumour necrosis factor alpha (TNF-a), for example

Clinical studies have proved an association between insulin resistance and cardiovascular risk However, the value of pharmacological agents that lower insulin resistance in reducing cardiovascular risk remains to be demonstrated

A 62-year-old retired postman awoke with 'darkened', impaired vision in the upper half of the visual field of his left eye 3 days prior

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to evaluation He described the onset of

symptoms as 'like a shade being pulled down'

over the visual picture He did not complain of

eye pain He had noted headache for 6 weeks

beforehand, and had consulted his GP on three

occasions about this He was told that he was

suffering from tension headache, and was

prescribed simple analgesics When

questioned specifically he reports having pain

at each side of his jaw when he eats, especially

towards the end of the meal He is

hypertensive and on treatment with a

Β-blocker He has never smoked

Which of the following diagnoses is likely?

1- Central retinal artery occlusion

2- Non-arteritic ischaemic optic neuropathy

3- Migraine

4- Arteritic ischaemic optic neuropathy

5- Optic neuritis

Answer & Comments

Answer: 4- Arteritic ischaemic optic

neuropathy

Altitudinal defects (from the bottom up, or the

top down) are common in vascular disorders of

the optic nerve head Vascular problems are

common on waking The preceding headache

raises the suspicion of temporal arteritis, the

feared complication of which is arteritic

anterior ischaemic optic neuropathy Jaw

claudication as described above is

pathognomonic of temporal arteritis

Non-arteritic ischaemic optic neuropathy is

common in patients with multiple vascular risk

factors, does not cause headache and is not

associated with raised inflammatory markers

Neurological signs precede headache in

migraine, which would be uncommon in this

age group, as would optic neuritis

A 44-year-old patient was referred to

the hospital because of a 3-day history of

general malaise associated with nausea, diarrhoea and headache On examination the patient looks well but red/bluish petechiae can

be seen on the extensor surfaces of both legs

1- Hepatitis C infection 2- Legionella infection 3- Neisseria meningitidis infection 4- Pneumocystis jiroveci infection 5- Active tuberculosis

Answer & Comments

Answer: 3- Neisseria meningitidis infection

Haemorrhagic skin lesions are the hallmark of systemic meningococcal disease, occurring in 70-80% of all cases in industrialised countries They appear as red or bluish petechiae These lesions are larger and more irregular in size than the petechiae of thrombocytopenic purpura Each lesion represents a local nidus of meningococci within the endothelial cells, thrombus formation and extravasation of erythrocytes The petechial rash indicates meningococcaemia, not necessarily severe sepsis Many patients are initially diagnosed as having gastric flu, gastroenteritis or an upper respiratory tract infection Pneumocystis jiroveci used to be called Pneumocystis carinii

What is the genetic mode of inheritance of Huntington's disease?

1- Autosomal-dominant 2- Autosomal-recessive 3- X-linked dominant 4- Polygenic inheritance 5- No genetic inheritance identified

Answer & Comments

Answer: 1- Autosomal-dominant

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Huntington's disease was first described in

1872 by an American physician His father and

grandfather practised medicine in the same

community, and thus he had access to

case-notes from several generations of families

living in the area This long period of record

keeping allowed him to document a hereditary

form of chorea, similar to 'common

(Sydenham's) chorea', but progressing over

many years to death Its sufferers had a

tendency to insanity and suicide Huntington's

brief essay, which also included a clear

description of the autosomal-dominant mode

of inheritance of this disorder, remains one of

the classical descriptions of a medical disorder

The disorder is caused by the expansion of an

unstable trinucleotide repeat sequence (CAG)

in the first exon of a gene near the telomere of

chromosome 4p Normally, this trinucleotide

sequence contains about 7-30 repeats; when

the number rises above 37, Huntington's

disease occurs It is transmitted as an

autosomal-dominant trait; if one parent is

affected, each offspring (regardless of sex) has

an independent 50% chance of having

inherited the abnormal gene Those who

inherit the gene will almost certainly develop

Huntington's disease The mutation rate is low,

so most patients will have an affected parent

However, it can be difficult to obtain an

accurate family history

A 70-year-old woman is investigated

for recurrent chest infections and bleeding

Routine investigations show a WCC 32 x

103/mm3, Hb 9.1 g/dl, platelets 37 x 103/mm3,

with a blood film showing cells of the myeloid

series at various stages of maturation

What further investigation will be most helpful

in terms of diagnosis?

1- Cytogenetic analysis

2- Neutrophil LAP score

3- Bone marrow trephine

4- Immunophenotyping 5- Bone marrow aspirate

Answer & Comments

Answer: 3- Bone marrow trephine

Marrow failure with a large number of circulating myeloid series' cells is either due to chronic myelogenous leukaemia (CML) or myelofibrosis - the clinical presentation and routine investigations are often the same in both conditions The demonstration of marrow fibrosis requires a trephine biopsy as the aspirate is often 'dry' Cytogenetic analysis can

be helpful as the Philadelphia chromosome is negative in myelofibrosis, but is also negative

in 5% of cases of CML The neutrophil leucocyte alkaline phosphatase (LAP) score is normal or high in myelofibrosis and low in CML, but this

is not diagnostic The trephine appearance in CML is of a marrow full of myeloid precursors

A 73-year-old man with chronic lymphocytic leukaemia (CLL) is followed up in clinic He has become increasingly breathless over the last three months but has no other symptoms and is on no medication On examination, he is pale and has bilateral cervical and inguinal lymphadenopathy and a firm 5-cm splenomegaly FBC shows:Hb 7.4 g/dl; WCC 25 x 103/mm3; platelets 117 x

103/mm3; urea 15 mmol/l; creatinine 203 mmol/l; bilirubin 49 mmol/l

Which investigation is most appropriate to demonstrate the likely cause of anaemia?

1- Bone marrow aspirate 2- Autoantibody profile 3- Erythropoietin level 4- Antiglobulin test 5- Urinary haemosiderin

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Answer & Comments

Answer: 4- Antiglobulin test

Anaemia in CLL has several causes including

marrow infiltration, marrow suppression from

chemotherapeutic agents, hypersplenism and

haemolysis (which is extravascular and

mediated by IgG antibodies against the

erythrocyte membrane) A disproportionately

low haemoglobin compared to the platelet

count is more likely to reflect a red cell problem

alone; and the raised bilirubin level suggests

that haemolysis is occurring, rather than the

anaemia being due to marrow failure

Autoimmune haemolysis is demonstrated by

the antiglobulin test, either indirectly (patients'

serum incubated with human red cells and

antiglobulin antibodies) or directly (patients'

cells and serum incubated with antiglobulin

antibody) The haemolysis is extravascular and

so there will be no increase in urinary

haemosiderin

A 75-year-old man with a history of

atrial fibrillation and peripheral vascular

disease presents to the emergency

department His abdomen is distended and

tender A plain abdominal film shows

thumb-printing at the site of the splenic flexure Blood

testing reveals evidence of mild dehydration,

and a full blood count shows a mildly raised

Answer & Comments

Answer: 1- Ischaemic colitis

Ischaemic colitis occurs with increasing frequency in patients taking the contraceptive pill, who have a thrombophilia syndrome, or who have a history of pre-existing vascular disease, as in this case The plain abdominal film is characteristic, when 'thumb-printing' occurs at the site of the splenic flexure Management is usually conservative with iv rehydration and supportive management Unfortunately though, some cases can progress to gangrene and perforation and require surgical intervention for partial colectomy One long-standing consequence of

a resolved episode may be stricture formation

in the previously ischaemic area

A 73-year-old man with advanced Parkinson's disease is being treated on the ward for a urinary tract infection His regular medication includes co-careldopa, entacapone, cabergoline, and prn subcutaneous apomorphine injections His wife tells you that for the last month his behaviour has changed and he has become agitated, disinhibited and he keeps asking her for money His dyskinesia has also become more pronounced over this period On examination, he is distractable He denies having hallucinations and, after probing questioning, you can find no evidence of delusional thought Mood assessment shows him to be cheerful and there are no cognitive

or biological features of depression

What is the likely physiological cause of the behavioural change?

1- Reduced breakdown of dopamine 2- Change in sensitivity to dopamine 3- Confusional state due to urosepsis 4- Direct dopamine agonism

5- Coexisting dementia

Answer & Comments

Answer: 4- Direct dopamine agonism

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Neuropsychiatric complications of Parkinson's

disease (PD) are common - experienced by

some 70% of all patients Hedonistic

dysregulation is being increasingly recognised;

here patients typically take increasing amounts

of a dopamine agonist even though it worsens

their dyskinesia (usually apomorphine is

abused in this way) This results in euphoria,

hypersexuality and gambling There is an

extensive body of research literature on

dopamine reward pathways (from the ventral

tegmental area to the nucleus accumbens) as

the mediator of motivation and possibly drug

addiction The commonest psychiatric

complication, however, is depression (50%,

associated with a younger onset, female

gender), anxiety (40%), psychosis (40%, visual

hallucinations and persecutory delusions,

often drug related) and dementia (20-40%

associated with an older onset PD, severe

extrapyramidal features)

You are asked by your orthopaedic

colleagues to review a 28-year-old victim of

blunt trauma after a motorcycle accident He

has suffered extensive lower limb damage and

requires large amounts of analgesia The

orthopaedic surgeons are concerned about his

blood results, his potassium some hours after

the accident is 6.7 mmol/l, calcium is 2.05

mmol/l, urine is positive to dipstick testing for

of rhabdomyolysis The rise in CK levels is detectable a few hours after injury and peaks

at the 48-h stage

Rhabdomyolysis is also common after electrical injury, compartment syndrome, prolonged limb or tourniquet anaesthesia, extensive surgical dissection and infectious or inflammatory myopathies

What is the mechanism of action of carbimazole?

1- Destruction of functioning thyroid cells 2- Inhibition of 5'-deiodinase

3- Inhibition of the iodination of tyrosine 4- Inhibition of thyroglobulin proteolysis 5- Conversion to methimazole, which blocks the TSH receptor

Answer & Comments

Answer: 3- Inhibition of the iodination of

tyrosine Carbimazole is converted to its active metabolite, methimazole, in the body It reduces the synthesis of new thyroid hormones

by inhibiting the iodination of tyrosine and coupling of precursors to form thyroxine It also has an immunosuppressive action leading to a reduction in serum thyrotrophin (TSH)-receptor antibody (TRAb) concentrations It does not destroy functioning thyroid cells Propylthiouracil inhibits 5'-deiodinase and prevents the release of free T3 and T4 from the

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