Part 2 book “Symptom to diagnosis” has contents: Wheezing and stridor, sore throat, weight loss, unintentional, kidney injury, acute, jaundice and abnormal liver enzymes, hematuria, hypertension, hypercalcemia, GI bleeding, fatigue, edema,… and other contents.
15 I have a patient with dyspnea How I determine the cause? CHIEF COMPLAINT PATIENT Mr C is a 64-year-old man who comes to see you complaining of shortness of breath What is the differential diagnosis of dyspnea? How would you frame the differential? CONSTRUCTING A DIFFERENTIAL DIAGNOSIS Heart disease, lung disease, and anemia are the most common causes of dyspnea Neuromuscular disease and anxiety are less common causes The simplest approach to the differential diagnosis is to consider the anatomical components of each of these systems This allows us to develop a fairly comprehensive differential diagnosis of dyspnea Differential Diagnosis of Dyspnea A Heart Endocardium: Valvular heart disease (ie, aortic stenosis, aortic regurgitation, mitral regurgitation, and mitral stenosis) Conduction system a Bradycardia (sick sinus syndrome, atrioventricular block) b Tachycardia (1) Atrial fibrillation and other supraventricular tachycardias (2) Ventricular tachycardia Myocardium: Heart failure (HF) a Systolic failure (coronary artery disease [CAD], hypertension, alcohol abuse) b Diastolic failure (hypertension, aortic stenosis, hypertrophic cardiomyopathy) Coronary arteries (ischemia) Pericardium (tamponade, constrictive pericarditis) B Lung Alveoli a Pulmonary edema (HF or acute respiratory distress syndrome) b Pneumonia Airways a Suprathoracic airways (ie, laryngeal edema) b Intrathoracic airways (1) Asthma (2) Chronic obstructive pulmonary disease (COPD) (see Chapter 33, Wheezing & Stridor) Blood vessels a Pulmonary emboli b Primary pulmonary hypertension Pleural a Pneumothorax b Pleural effusions (1) Transudative (a) HF (b) Cirrhosis (c) Nephrotic syndrome (d) Pulmonary embolism (PE) (2) Exudative (a) Tuberculosis (b) Cancer (c) Parapneumonic effusions (d) Connective tissue diseases (e) PE Interstitium a Edema b Inflammatory (1) Organic exposures (eg, hay, cotton, grain) (2) Mineral exposures (eg, asbestos, silicon, coal) (3) Idiopathic diseases (eg, sarcoidosis, scleroderma, systemic lupus erythematosus, granulomatosis with polyangiitis [formerly Wegener granulomatosis]) c Infectious C Anemia The extensive differential diagnosis for dyspnea necessitates a careful and detailed history, physical exam and review of basic laboratory examinations including chest film, ECG, and hematocrit The history should detail the time course of the complaint, its severity, associated symptoms, and the patient’s past medical history The physical exam should include vital signs, a detailed cardiac and pulmonary exam, and a search for signs suggestive of anemia (conjunctival pallor or palmar crease pallor) This process often suggests the diagnosis However, when the diagnosis is not straightforward, certain pivotal findings can narrow the differential diagnosis and focus the diagnostic search (Figure 15-1) One such pivotal clue is fever Fever is typically seen in pneumonia but could also be seen in asthma or COPD with concomitant infection Less common causes of fever and dyspnea include valvular heart disease due to endocarditis, pulmonary emboli, acute respiratory distress syndrome, or interstitial lung disease Chest pain (covered extensively in Chapter 9) is another pivotal clue in patients with dyspnea Chest pain may be pleuritic or nonpleuritic and acute or chronic/recurrent Each of these features can help focus the differential diagnosis (see Figure 15-1, Table 15-1) In brief, common causes of dyspnea and pleuritic chest pain are pneumonia, PE, pneumothorax, asthma, and COPD On the other hand, many diseases may cause nonpleuritic chest pain (including those diseases already mentioned that may cause pleuritic chest pain) In these patients, the acuity of the chest pain can help narrow the differential diagnosis Common causes of dyspnea associated with acute chest pain include myocardial infarction (MI), aortic dissection, PE, pneumothorax, arrhythmias (causing angina), and pneumonia Common causes of dyspnea associated with chronic/recurrent chest pain include angina (caused by CAD, severe anemia, or aortic stenosis), asthma or COPD (which are often associated with chest tightness), and recurrent intermittent arrhythmias Figure 15-1 A diagnostic approach to dyspnea Table 15-1 Differential diagnosis of dyspnea and chest pain In patients with any of any of the aforementioned pivotal clues (fever, chest pain), a search for risk factors, associated symptoms and signs of those diseases can help rank the differential diagnosis Table 15-2 lists the highly suggestive risk factors as well as associated symptoms and signs of common diseases causing dyspnea Table 15-2 Common causes of dyspnea: highly suggestive risk factors, associated symptoms, signs, and tests When these pivotal clues are absent, it is appropriate to evaluate the most common causes of dyspnea, namely HF, pneumonia, asthma, COPD, and pulmonary emboli Once again, looking for their respective risk factors, associated symptoms and specific signs can help determine their likelihood Features that suggest HF include a history of MI, CAD risk factors, long-standing uncontrolled hypertension, or alcohol abuse Furthermore, an S3 gallop or jugular venous distention (JVD) are fingerprints for HF Fever and cough raise the possibility of pneumonia and a significant smoking history (≥ 20 pack years) raises the possibility of COPD Wheezing—defined as a multi-pitched sound on exhalation—suggests COPD or asthma Finally, PE can be obvious or subtle and should be considered in patients with risk factors such as recent immobilization, surgery, a history of cancer, or use of estrogen, or suggestive signs (eg, unilateral leg swelling) Some patients remain difficult to diagnose For such patients a more comprehensive review of risk factors, associated symptoms and signs (Table 15-2) as well as a careful review of their chest film findings may be helpful (Table 15-3) A normal chest radiograph makes pneumonia, interstitial lung disease, and acute respiratory distress syndrome unlikely and rules out pneumothorax Focal infiltrate(s) suggest pneumonia and can also be seen with COPD or asthma due to atelectasis or superimposed infection Diffuse infiltrates or edema may be seen in a variety of settings including any cause of HF, acute respiratory distress syndrome, and certain pneumonias The presence of a pleural effusion is a critical clue that should be evaluated Table 15-3 Typical radiographic patterns found in dyspneic patients Other diagnostic testing that is often necessary includes echocardiography, pulmonary function tests, B-type natriuretic peptide (BNP), and CT angiography (CTA) Echocardiography can reveal unsuspected HF or valvular heart disease Pulmonary function tests can help determine whether the patient has obstructive, restrictive, or vascular lung disease (Table 15-4) Figure 15-1 summarizes a diagnostic approach to patients with dyspnea Table 15-4 Pulmonary function test (PFT) abnormalities in lung disease Over the last years, Mr C has noticed worsening dyspnea on exertion He complains of primary cough headache, 336–337 primary exertional headache, 336–337 primary vs secondary, 325 subarachnoid hemorrhage, 335–336 subdural hematoma, 340 as symptoms of other diseases, morning, 333–334 temporal arteritis, 339–340, 339t tension headaches, 329–330 due to unruptured CNS aneurysm, 331 Headache (in HIV-positive patients), 77–84 cryptococcal meningoencephalitis, 80–81 differential diagnosis, 77–80, 78f, 79f, 80t HIV encephalopathy, 84–85 neurosyphilis in HIV-positive patients, 85–86 primary CNS lymphoma, 83–84 progressive multifocal leukoencephalopathy, 83 toxoplasmosis encephalitis, 81–82, 82f Healthcare-associated pneumonia (HCAP), 183–184 Heart failure (HF): dyspnea, 257–262, 259t, 260f, 260t and hyponatremia, 385–386 Hematuria, 345–353 bladder cancer, 346–349 differential diagnosis, 345–346, 346t, 347f, 348f, 349t, 351t IgA nephropathy, 351–352 infection-related glomerulonephritis, 352–353 renal cell carcinoma, 349–350 synpharyngitic, 351 thin basement membrane nephropathy, 352 Hemolysis, 99, 109–110 Hemorrhoidal bleeding, 321–322 Heparin-induced thrombocytopenia (HIT), 136–137, 136t Hepatitis, autoimmune, 431, 431t Hepatitis A, 423–424, 423f Hepatitis B, 424–426, 424f, 425f Hepatitis C, 426–427, 426f, 427t Hereditary hemochromatosis, 430–431 Herniated disk, 120–122, 121t HF (see Heart failure) HIT (see Heparin-induced thrombocytopenia) HIV encephalopathy (HIV-associated dementia), 84–85 HIV infection: diagnosis, 73–74 headache with (see Headache (in HIV-positive patients)) stages of, 72–73 treatment of, 74–76 Hospital-acquired pneumonia (HAP), 183–184 Humoral hypercalcemia of malignancy, 360–361 Hyperbilirubinemia (see Jaundice) Hypercalcemia, 355–363 differential diagnosis, 355, 356f, 357t, 360t familial hypocalciuric hypercalcemia, 358 humoral hypercalcemia of malignancy, 360–361 local osteolytic hypercalcemia of malignancy, 361–362 milk-alkali syndrome, 362 primary hyperparathyroidism, 356–358 secondary & tertiary hyperparathyroidism, 362–363 thiazide-induced hypercalcemia, 359 Hypercholesterolemia, 213 Hyperglycemia, 209–213, 210f, 210t Hyperlipidemia, screening for, 15–16 Hypernatremia, 396–399 differential diagnosis, 396–398, 397f, 398t secondary to inadequate water intake, 398–399 Hyperosmolar hyperglycemic state, 214–216, 215f, 215t Hyperparathyroidism: primary, 356–358 secondary & tertiary, 362–363 Hypersplenism, 292–293 Hypertension, 213, 365–377 atherosclerotic renal artery stenosis, 371–373 differential diagnosis, 365–366, 366t, 367t, 371t, 374t essential hypertension, 366–370, 367t, 369f, 370t hypertensive emergencies, 375–376 hypertensive urgency, 374–375 lifestyle changes in, 367t nonpharmacologic approaches to managing, 367t, 368t pheochromocytoma, 376–377, 376t, 377t portal, 290–293 primary hyperaldosteronism, 373 Hypertensive emergencies, 375–376 Hypertensive urgency, 374–375 Hyperthyroidism, 531–534, 532t, 533f Hypertrophic cardiomyopathy, 504–506 Hyponatremia, 379–396 adrenal insufficiency, 389–393, 391f approach to treatment, 385t cirrhosis, 383–385, 384t differential diagnosis, 379–383, 380f–383f, 384t, 388t diuretic-induced, 393 Ecstasy intoxication, 395 exercise-associated, 394 heart failure and hyponatremia, 385–386 hypothyroidism, 393–394 hypovolemic hyponatremic syndromes, 394 nephrotic syndrome, 386–387 pseudohyponatremia, 395–396 psychogenic polydipsia, 394–395 symptoms, 383 syndrome of inappropriate antidiuretic hormone, 388–389, 389t vaptan treatment, 386t Hypopnea, 308 Hypotension, 401–412 anaphylactic shock, 411–412 cardiac tamponade, 409–410 cardiogenic shock, 408–409, 408t differential diagnosis, 401, 404t, 411t hypovolemic shock, 406–407, 407t septic shock, 402–406, 403f, 405f, 405t Hypothyroidism, 310–311, 393–394 Hypovolemia, 69f Hypovolemic hyponatremic syndromes, 394 Hypovolemic shock, 64, 64t, 406–407, 407t I IBS (see Irritable bowel syndrome) Idiopathic intracranial hypertension, 341 Idiopathic thrombocytopenic purpura (ITP), 134 IgA nephropathy, 351–352 Infectious mononucleosis, 494–495, 494t Influenza, 179–183, 180f, 181t INR (international normalized ratio), 138 Insomnia, 306–307, 307t International normalized ratio (INR), 138 Interstitial nephritis, 465–466, 466t Intracerebral hemorrhage, 337–338 Intracranial neoplasms, 240, 332–333 Iron deficiency anemia, peptic ulcer disease in, 102–104 Irritable bowel syndrome (IBS), 545–548 Crohn disease, 543f, 545–547 ulcerative colitis, 547–548 unintentional weight loss, 545–548 Ischemic bowel, 36f, 44–46, 45t abdominal pain, 36f, 44–46, 45t acute mesenteric ischemia, 44–45, 45t chronic mesenteric ischemia, 51–52 ischemic colitis, 45–46, 45t Ischemic colitis, 45–46, 45t ITP (idiopathic thrombocytopenic purpura), 134 J Jaundice (hyperbilirubinemia), 415–432 acute hepatitis B, 424–425, 424f alcoholic liver disease, 419–420 autoimmune hepatitis, 431, 431t chronic hepatitis B, 425–426 differential diagnosis, 415–416, 416t, 417f, 418t, 422t, 429t elevated alkaline phosphatase, 432f elevated serum bilirubin, 417f hepatitis A, 423–424, 423f hepatitis B, 424, 425f hepatitis C, 426–427, 426f, 427t hereditary hemochromatosis, 430–431 nonalcoholic fatty liver disease, 429–430 pancreatic cancer, 420–422, 420t, 421f Joint pain, 435–453 calcium pyrophosphate dihydrate deposition disease, 439 differential diagnosis, 435, 436f, 437t, 442t, 447t, 451t disseminated gonorrhea, 440–441, 441t femoral stress fractures, 452–453 gout, 436–439, 438t Lyme disease, 441 osteoarthritis, 450–452, 451f, 452t parvovirus, 447–448 periarticular syndromes, 453, 453t psoriatic arthritis, 444–445 reactive arthritis, 448–449, 449t rheumatic fever, 449–450, 450t rheumatoid arthritis, 442–444, 443f, 444t septic arthritis, 440 systemic lupus erythematosus, 445–446, 445t, 446t viral causes of arthritis, 448t K Kaposi sarcoma, 95–96, 96f Ketoacidosis: alcoholic, 62 diabetic, 59–62 Kidney function, measuring, 456, 458 Kidney injury, acute (see Acute kidney injury) L Lactic acidosis: acid-base abnormality, 56t, 64–65, 64t secondary to sepsis, 65t Lactose intolerance, 222–223 Lacunar infarction of the pons or cerebellum, 245–246, 246f Large bowel obstruction (LBO), 42–43, 42t Latent tuberculosis (TB) infection, 174 LBO (see Large bowel obstruction) Lemierre syndrome, 497–498 Lightheadedness, 229, 230f, 231f Likelihood ratio (LR), 6–7, 7f negative, positive, 6–7 Lipid panel, 15–16 Liver disease: alcoholic, 419–420 induced coagulopathy, 139–140 nonalcoholic fatty liver disease, 429–430 Local osteolytic hypercalcemia of malignancy, 361–362 Low back pain, 115–130 differential diagnosis, 115–119, 116f–118f, 117t, 119t, 123t, 124t herniated disk, 120–122, 121t mechanical low back pain, 119–120 due to metastatic cancer, 123–124, 123t osteoporotic compression fracture, 124–125 peripheral arterial disease, 128–129, 128t spinal epidural abscess, 129 spinal stenosis, 125–127, 127t vertebral osteomyelitis, 129–130 LR (see Likelihood ratio) Lung cancer, screening for, 17, 18t Lyme disease, 441 M MAC (see Mycobacterium avium complex) Major cognitive disorder, 187 Malabsorption with folate deficiency, 106 Mallory-Weiss tear, 320–321 Mammograms, 20–22 MCI (mild cognitive impairment), 197–198 MDMA (Ecstasy) intoxication, 395 Mechanical low back pain, 119–120 Melanoma, 487–488, 487f Meniere disease, 237 Meningitis, 341–342, 342t Mesenteric ischemia, acute, 44–45, 45t Metabolic alkalosis, 68–69, 69f Metastatic cancer, low back pain due to, 123–124, 123t MI (see Acute myocardial infarction) Migraine: headache, 327–329, 327t, 328t, 329t vestibular, 247–248 Mild cognitive impairment (MCI), 197–198 Milk-alkali syndrome, 362 Mitral regurgitation (MR), 262–263 Mixed disorders (acid-base abnormality), 70 Morning headaches as symptoms of other diseases, 333–334 MR (see Mitral regurgitation) MS (multiple sclerosis), 239–240 Multi-infarct dementia (vascular dementia, VaD), 196–197 Multiple sclerosis (MS), 239–240 Multiple sensory deficits, 250 Musculoskeletal disorders, back pain due to, 115 Mycobacterium avium complex (MAC), cough and fever and, 95 Myocardial infarction (MI), 150–153, 151t N NAFLD (nonalcoholic fatty liver disease), 429–430 National Guideline Clearinghouse (NGC) guidelines, 10 National Osteoporosis Foundation (NOF) guidelines, for osteoporosis, 24 Near syncope, 229, 230f, 230t (See also Dizziness) Negative LR, Nephrolithiasis, 48–49 Nephropathy, 206 IgA, 351–352 thin basement membrane, 352 Nephrotic syndrome: edema, 293–294 hyponatremia, 386–387 Neurocardiogenic (vasovagal) syncope, 502–503, 503f, 504f Neuropathy, 203–205, 205t Neurosyphilis in HIV-positive patients, 85–86 NGC (National Guideline Clearinghouse) guidelines, 10 NOF (National Osteoporosis Foundation) guidelines, for osteoporosis, 24 Nonalcoholic fatty liver disease (NAFLD), 429–430 Nonspecific dizziness, 229, 230t, 241–242 Norovirus, 219–220 NSAID-induced renal hypoperfusion, 465 Nummular dermatitis, 483, 483f O OA (see Osteoarthritis) Obscure GI bleeding, 323 Obstructive sleep apnea (OSA), 307–309 Occult GI bleeding, 322–323 Organ/system frameworks for diagnosis, Orthostatic hypotension, 242–243, 518–519, 519t OSA (obstructive sleep apnea), 307–309 Osteoarthritis (OA), 450–452, 451f, 452t Osteoporosis, screening for, 22, 24 Osteoporotic compression fracture, 124–125 P PAD (see Peripheral arterial disease) Pancreatic cancer, 420–422, 420t, 421f Pancreatitis: acute, 36t, 38–41 chronic, 542–544 evaluation of, 40f Pap smear, 19–20 Paradoxical vocal cord movement (PVCM), 559 Parvovirus, 447–448 Pathophysiologic frameworks for diagnosis, Patient-specific differential diagnosis, PCP (Pneumocystis jiroveci pneumonia), 172–173 PE (see Pulmonary embolism) Peptic ulcer disease (PUD): GI bleeding, 319–320, 320t unintentional weight loss, 535–539, 535f, 536t, 537f Periarticular syndromes, 453, 453t Pericarditis, acute, 159–160 Periodic limb movement disorder (PLMD), 310 Peripheral arterial disease (PAD), 128–129, 128t Peritonsillar abscess, 496–497 Pertussis, 184 Petechiae, 484–485 Pheochromocytoma, 376–377, 376t, 377t Pityriasis rosea, 482, 482f Pivotal points, Pleural effusion, 156–159, 157t PLMD (periodic limb movement disorder), 310 Pneumocystis jiroveci pneumonia (PCP), 172–173 Pons, lacunar infarction of, 245–246, 246f Positive LR, 6–7 Possibilistic approach to diagnosis, Posttest probability, 5, 8t Potential harms of missed diagnosis/treatments, Pragmatic approach to diagnosis, Prediabetes, 200, 201 Pretest probability, 3, 4–5 validated CDR for, Primary CNS lymphoma, 83–84 Primary cough headache, 336–337 Primary exertional headache, 336–337 Primary hyperaldosteronism, 373 Primary hyperparathyroidism, 356–358 Probabilistic approach to diagnosis, 3, 5f, 6f Professional societies’ screening guidelines, 10 Prognostic approach to diagnosis, Progressive multifocal leukoencephalopathy, 83 Prostate cancer, screening for, 11–12 Prostate specific antigen (PSA), 11 Prostatitis, acute, 282–283 Prothrombin time (PT), 138 PSA (prostate specific antigen), 11 Pseudohyponatremia, 395–396 Psoriatic arthritis, 444–445 Psychogenic polydipsia, 394–395 PT (prothrombin time), 138 PUD (see Peptic ulcer disease) Pulmonary embolism (PE): dyspnea, 269–274, 270t, 271f, 272f syncope, 513–514 Pulmonary hypertension, 295–296, 295t Pulmonary TB in AIDS patients, 91–94, 92t, 93f Purpura, 484–485, 485f PVCM (paradoxical vocal cord movement), 559 Pyelonephritis, 281 R RA (see Rheumatoid arthritis) Ranking a diagnosis, 3, 3t Rash, 471–489 acne vulgaris, 474–475 basal cell carcinoma, 485–486 bullous arthropod bites, 478–479, 478f bullous impetigo, 477–478, 478f bullous pemphigoid, 479, 479f differential diagnosis, 471–473, 473t, 476t, 481t, 489t guttate psoriasis, 481–482 melanoma, 487–488 nummular dermatitis, 483, 483f petechiae, 484–485 pityriasis rosea, 482, 482f purpura, 484–485, 485f rosacea, 475–476, 476f secondary syphilis, 483–484 skin cancer, 485–488, 486f–487f squamous cell carcinoma, 486–487 Stevens-Johnson syndrome, 479–480, 479f, 480t tinea corporis, 482–483, 483f urticaria, 484, 484f varicella zoster virus, 476–477 Reactivation tuberculosis (TB), 174 Reactive arthritis, 448–449, 449t Red blood cells, underproduction/destruction of, 99 Renal artery thrombosis, 468–469 Renal cell carcinoma, 349–350 Renal tubular acidosis (RTA), 68 RERA (respiratory effort-related arousal), 308 Respiratory acidosis, 67–68 Respiratory alkalosis, 70 Respiratory complaints, acute (see Acute respiratory complaints) Respiratory effort-related arousal (RERA), 308 Reticulocyte production index (RPI), 99 Retinopathy, as diabetic complication, 202–203 Retropharyngeal abscess, 562–563 Rhabdomyolysis, 466–468 Rheumatic fever, 449–450, 450t Rheumatoid arthritis (RA), 442–444, 443f, 444t Rosacea, 475–476, 476f RPI (reticulocyte production index), 99 RTA (renal tubular acidosis), 68 S SAH (subarachnoid hemorrhage), 335–336 SBO (small bowel obstruction), 43–44 Screening tests, 9–24 for abdominal aortic aneurysm, 18–19 for breast cancer, 20–22, 21t, 23t for carotid artery stenosis, 18–19 for cervical cancer, 19–20 for colon cancer, 13–15, 15t guidelines for, 9–11, 9t, 10f, 24t for hyperlipidemia, 15–16 for lung cancer, 17, 18t numbers needed to screen, 24t for osteoporosis, 22, 24 for prostate cancer, 11–12 reasoning behind, Secondary & tertiary hyperparathyroidism, 362–363 Secondary syphilis, 483–484 Seizures, 515–516, 515t, 516t Sensitivity, Septic arthritis, 440 Septic shock, 64, 64t, 402–406, 403f, 405f, 405t Serum bilirubin, 417f Sexual activity, headache associated with, 336–337 Shigella infection, 226–227 Shock: anaphylactic, 411–412 cardiogenic, 408–409, 408t differential diagnosis, 401–402 hemodynamic features of, 64t hypovolemic, 406–407, 407t septic, 402–406, 403f, 405f, 405t types of, 64 Sick sinus syndrome (SSS), bradycardia from, 512 Sickle cell anemia, 110–113, 111f, 112t Situational syncope, 521–522 Skin cancer: basal cell carcinoma, 485–486, 486f melanoma, 487–488, 487f rash, 485–488, 486f–487f squamous cell carcinoma, 486–487, 486f SLE (see Systemic lupus erythematosus) Small bowel obstruction (SBO), 43–44 Society of Vascular Surgery guidelines: for abdominal aortic aneurysm, 18 for carotid artery stenosis, 19 Sore throat, 491–498, 492t ARS, 495 differential diagnosis, 491–492, 492t, 496t GABHS pharyngitis, 492–494, 493t infectious mononucleosis, 494–495, 494t Lemierre syndrome, 497–498 peritonsillar abscess, 496–497 Specialty societies’ guidelines, 10 Specificity, Spinal epidural abscess, 129 Spinal stenosis, 125–127, 127t Squamous cell carcinoma, 486–487, 486f SSS (sick sinus syndrome), bradycardia from, 512 Stable angina, 145–148, 146t, 147t Starvation ketosis, 62 Stevens-Johnson syndrome, 479–480, 479f, 480t Stridor, 551 (See also Wheezing or stridor) Subarachnoid hemorrhage (SAH), 335–336 Subdural hematoma, 340 Substances or their withdrawal, headache associated with, 334 Syncope, 499–523 acute coronary syndrome, 511 aortic stenosis, 520–521, 520f bradycardia due to atrioventricular heart block, 512–513, 513f, 513t bradycardia from sick sinus syndrome, 512 cardiac syncope, 501f, 507–509, 508t carotid sinus syndrome, 522 cerebrovascular disease and, 516 differential diagnosis, 499–502, 500f, 502t, 507t, 514t, 517t hypertrophic cardiomyopathy, 504–506 neurocardiogenic syncope, 502–503, 503f, 504f orthostatic hypotension, 518–519, 519t pulmonary embolism, 513–514 seizures, 515–516, 515t, 516t situational syncope, 521–522 ventricular tachycardia, 509–511, 510f, 511f Wolff-Parkinson-White syndrome, 522–523, 522f, 523f Syndrome of inappropriate antidiuretic hormone, hyponatremia and, 388–389, 389t Synpharyngitic hematuria, 351 Systemic diseases, back pain due to, 115 Systemic lupus erythematosus (SLE), 445–446, 445t, 446t T TB (see Tuberculosis) Temporal arteritis, 339–340, 339t Tension headaches, 329–330 Test characteristics, 6, 6f Test threshold, Tests (see Screening tests) Thiazide-induced hypercalcemia, 359 Thin basement membrane nephropathy, 352 Threshold model, 5, 5f, 6f Thromboembolism of the renal arteries, 468–469 Thrombotic thrombocytopenic purpura (TTP), 135 Tinea corporis, 482–483, 483f Toxin-mediated gastroenteritis, 220, 221t Toxoplasmosis encephalitis, 81–82, 82f Travelers’ diarrhea, 228 TTP (thrombotic thrombocytopenic purpura), 135 Tuberculosis (TB), 173–179, 175t, 176t, 177t, 178f pulmonary TB in AIDS patients, 91–94, 92t, 93f Type diabetes mellitus, 199 Type diabetes mellitus, 200–202, 200t, 201t, 209, 212f U UEDVT (see Upper extremity DVT) Ulcerative colitis, 547–548 Ultrasonography, for abdominal aortic aneurysm, 18 for carotid artery stenosis, 18–19 Unconjugated bilirubin, 415 Unintentional weight loss, 525–549 alcoholism, 539–542, 541t bacterial overgrowth, 545 cancer cachexia, 528–529 celiac disease, 548–549, 549f chronic pancreatitis, 542–544 depression, 529–531 differential diagnosis, 525–527, 526t, 528t, 535t, 540t hyperthyroidism, 531–534, 532t, 533f irritable bowel syndrome, 545–548 peptic ulcer disease, 535–539, 535f, 536t, 537f Unstable angina, 153–154, 154t Upper extremity DVT (UEDVT), 301–302, 301t Uremic acidosis, 62 Urethritis, 283–284 Urinary tract obstruction, 462–463 Urobilinogen, 415 Urosepsis, 284 Urticaria, 484, 484f US Preventive Services Task Force (USPSTF) screening guidelines, 10–11, 24t for abdominal aortic aneurysm, 18 for carotid artery stenosis, 19 for colon cancer, 14, 15 for hyperlipidemia, 16 for lung cancer, 17 for mammography, 21 for osteoporosis, 22, 24 for Pap smears, 20 for prostate cancer, 12 V VaD (vascular dementia), 196–197 VAD (vertebral artery dissection), 249–250 Vaginitis, 279–281, 280t VAP (ventilator-associated pneumonia), 183–184 Varicella zoster virus (herpes zoster/shingles), 476–477 Vascular dementia (VaD), 196–197 VBI (vertebrobasilar insufficiency), 244–245 Venous insufficiency, 296–298, 297f Ventilator-associated pneumonia (VAP), 183–184 Ventricular tachycardia (VT), 509–511, 510f, 511f Vertebral artery dissection (VAD), 249–250 Vertebral osteomyelitis, 129–130 Vertebrobasilar insufficiency (VBI), 244–245 Vertigo, 229, 230f, 230t, 232t, 236t (See also Dizziness) Vestibular migraine, 247–248 Vestibular neuritis, 238–239 Visceral disease, back pain due to, 115 Vitamin K deficiency, 140–141 VT (see Ventricular tachycardia) W Water intake, inadequate, hypernatremia secondary to, 398–399 Weight loss, unintentional (see Unintentional weight loss) Wheezing or stridor, 551–567 angioedema, 559–561, 560f asthma, 553–558, 554t, 555f, 556t, 557f bronchiectasis, 566–567 chronic obstructive pulmonary disease, 563–566, 565t, 566t differential diagnosis, 551, 553t, 559t, 561t, 563t epiglottitis, 561–562 evaluation of, 552f paradoxical vocal cord movement, 559 retropharyngeal abscess, 562–563 Wolff-Parkinson-White (WPW) syndrome, 522–523, 522f, 523f ... Death a Symptomatic mild to moderate HF: 20 –30% per year b Symptomatic severe HF: up to 50% per year c Mechanism of death (1) Sudden in 50% (secondary to ventricular tachycardia or asystole) (2) Progressive... DIFFERENTIAL DIAGNOSIS Although the differential diagnosis of dyspnea is broad, the patient’s risk factors, symptoms and signs point to a cardiac etiology and immediately focus the differential diagnosis. .. decreased ejection fraction) without signs or symptoms of HF c Stage C: Structural heart disease and prior or current symptoms d Stage D: Refractory HF symptoms despite therapy E Complications of HF