Pathophysiology Review - part 10 potx

e142 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review If I were your teacher, I would test you on . . . ț Most common cause of fungal meningitis. ț Clients at risk (immunocompromised clients, such as those with cancer (Hodgkin’s disease) or HIV/AIDS and those receiving long- term steroid therapy (remember long-term steroid therapy leads to immunosuppression). ✚ Aspergillosis What is it? Aspergillus is a mold found in organic decaying matter or decomposing plant matter, soil, household dust, building materials, ornamental plants, food, and water. Essentially, this mold is everywhere! It is the causative agent of aspergillosis. Causes and signs and symptoms Table 20-33 shows the cause of infection and the associated signs and symptoms. Ǡ Figure 20-10. Aspergillus: an opportunistic fungus. (Photo generously provided by the CDC.) Table 20-33 Causes Signs and symptoms Inhalation of Aspergillus can cause Shortness of breath related symptoms of asthma to bronchospasm Aspergillus can grow in the lung to Cough the extent of forming a ball (aspergilloma), Fever requiring surgical removal Sinus trouble Severely immunocompromised clients (such as those with very advanced (see Fig. 20-10) AIDS) are at risk for pneumonia and systemic illness Source: Created by author from References #1 and #2. Quickie tests and treatments Tests include: ț Chest x-ray to show aspergilloma (fungal ball). CHAPTER 20 ✚ Infectious Diseases e143 ț Computed tomography (CT) scan of the chest. ț Biopsy, the diagnostic test of choice. Sputum cultures are not reliable. Treatment includes: ț Voriconazole (antifungal). ț Amphotericin B (antifungal). What can harm my client? ț During construction projects, this mold has been known to be released, causing the death of immunocompromised clients. ț Bone marrow transplant clients have almost zero immunity. If con- struction occurs near their unit, they can breathe in the released mold, which ultimately causes death. ț Opening a client’s window can harm the client, especially if there is a construction project going on outside of the hospital. ț Fresh flowers or plants brought in by family and friends can be a source of infection. ț Permanent lung damage can occur in those with chronic disease. According to the CDC, 10% mortality rates occur in clients with HIV who have disseminated disease. If I were your teacher, I would test you on . . . ț Significance of this mold as it relates to hospitalized clients and construction projects. ț Complications. ✚ Pneumocystis jiroveci What is it? Once known as Pneumocystis carinii, this fungus is found in the lungs of rats. P. jiroveci is the species responsible for infecting humans. The fungus lives in the environment and generally does not cause an infec- tion in those who have a healthy immune system (Fig. 20-11). Infection-control professionals are involved in construction projects to make sure barriers are put up to protect our clients from Aspergillus. ǡ Figure 20-11. Pneumocystis carinii, now called Pneumocystis jiroveci, is present in this lung impression smear. (Photo generously provided by the CDC.) e144 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Causes and signs and symptoms Table 20-34 shows the cause of infection and the associated signs and symptoms. Table 20-34 Causes Signs and symptoms Transmission of P. jiroveci is believed to be by the airborne route P. jiroveci causes pneumonia in 80% of AIDS clients and is a major cause of death among them P. jiroveci also causes pneumonia in immunocompromised clients, such as chemotherapy recipients Source: Created by author from Reference #5. Abrupt onset of fever Tachypnea (increased respirations) Shortness of breath Nonproductive cough Pneumothorax (collapsed lung), in some clients Symptoms may be minimal even in severe illness. Rapid deterioration and death occur without treatment Quickie tests and treatments Tests include: ț Chest x-ray. ț Computed tomography (CT) scan of the chest. ț Sputum specimen sent to lab for specific stains. Cannot be cultured. ț Transbronchial lung biopsy (via the bronchus), may be performed, if results of the sputum test are negative. Blood tests are not helpful. Treatment may include: ț Bactrim given orally or IV, depending on the severity of disease. ț Clindamycin/primaquine, dapsone/trimethoprim, pentamidine, and atovaquone. ț Steroids. Prophylactic treatment is given to AIDS clients to prevent this infection. These clients are given antibiotics such as Bactrim or pentamidine inhalations for the rest of their lives to prevent them from developing the disease. What can harm my client? ț Rapid deterioration and death, if the infection is not diagnosed and treated quickly. If I were your teacher, I would test you on . . . ț What is it? ț Where does it come from? ț Which clients have the highest risk of infection? ț What are the complications? ț What prophylactic treatment is given to AIDS clients? CHAPTER 20 ✚ Infectious Diseases e145 VIRUSES ✚ Let’s get the normal stuff straight first Viruses are simple living things that consist of either DNA or RNA. They require a live host to reproduce. When introduced into living host cells, they modify cell metabolism to produce new nucleic acid and proteins that are released from the cell to invade other cells of the host. The release process can cause tissue damage, leading to signs and symptoms of infection. Viruses can live in the host for months to years. ✚ Hepatitis A What is it? Hepatitis A virus (HAV) is a virus that causes liver disease. Incubation is about 30 days, and the virus is excreted in the stool for about 2 weeks before the illness and about a week after it. The mortality rate is low. Children are typically asymptomatic. Adults generally have a more severe illness. The disease is not chronic and is not “carried”: ț An HAV infected person working in a restaurant uses the restroom (bowel movement) without washing his hands before going back to work. He prepares food and contaminates it with the HAV from his contaminated hands. You eat the food and now you have been infected with HAV. ț Another example may occur when you eat raw oysters that have been in water that is contaminated with HAV. ț You eat contaminated food imported from another country (e.g., green onions). Signs and symptoms and why Table 20-35 covers the signs and symptoms and rationales associated with HAV infections. Table 20-35 Signs and symptoms Why Jaundice Impaired excretion of conjugated bilirubin Clay stools causes staining of skin known as jaundice, and the bile pigment in feces is reduced causing it to be clay colored Dark urine Impaired excretion of conjugated bilirubin into the kidneys Pruritus (meaning the client is Accumulation of bile salts in the skin itching in the absence of rash) Right upper quadrant abdominal Swelling of the inflamed liver pain (Continued) HAV is the only viral hepatitis causing spiking fevers. Outbreaks can occur in day care centers. The reason is that babies are asymptomatic, and during dia- per changes, the day care workers contaminate their hands. If they do not wash them during diaper changes, they can transmit the virus to other babies through direct contact. Other babies put their hands in their mouths, and get HAV. Yuk!! e146 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Quickie tests and treatments ț A blood test detects the presence of the antibody IgM. ț No specific treatment is effective after clinical signs appear. Prevention includes: ț Hand hygiene after using the bathroom and before preparing food. ț Properly cleaning eating utensils. ț Exclusion of food handlers from work. ț Providing vaccination. If there has been exposure to HAV, immune globulin (preparation of antibodies) must be given within 2 weeks of exposure. Immune globulin may be given before exposure for short-term protection only, i.e., those planning to travel to ↑ risk areas. HAV vaccine is available to persons 12 months of age and older. INFECTION CONTROL ț Hand hygiene to prevent the spread of HAV. ț Vaccine before traveling to places where HAV is endemic. ț Standard precautions, when caring for this client. ț Contact precautions, for incontinent clients (cannot control bladder/bowel). What can harm my client? ț Dehydration from nausea/vomiting. ț Since the bleeding/clotting factors can be altered with HAV, the client can experience a GI bleed or even a cranial bleed, causing a massive hemorrhage but this would be very rare with type A. The mortality rate of hep A is very low. Children are usually asympto- matic. It is the only viral hepatitis that causes high fevers. Table 20-35 (Continued) Signs and symptoms Why Fever Immune response to invading pathogen Fatigue Exact cause unknown Loss of appetite, nausea, GI symptoms are common with liver and vomiting infections Bleeding tendencies Decreased prothrombin synthesis; decreased vitamin K absorption because of decreased bile in intestines Anemia Because the liver enzymes are altered, the life of red blood cells is decreased; in severe cases, hemorrhage and bleeding may occur Source: Created by author from Reference #2 and #3. CHAPTER 20 ✚ Infectious Diseases e147 The risk of HBV infection through hemodialysis has been reduced significantly. Erythropoietin is now used to stimulate RBC production in those with renal failure, leading to a decreased need for blood transfusions! Dialysis clients now receive the HBV vaccine! If I were your teacher, I would test you on . . . ț Signs and symptoms. ț The spread of HAV and the best way to prevent its spread, including infection control. ✚ Hepatitis B What is it? Hepatitis B (HBV) is one of the five hepatitis viruses that infect the liver. This virus has a complex structure capable of attacking and destroying liver cells, resulting in illness or disease. Cellular destruction results in architectural changes of the normal structure, of the liver which leads to a disruption in the flow of blood and bile. Illness can range from mild signs and symptoms to chronic disease, such as fatal cirrhosis or liver cancer. What causes it and why Table 20-36 shows the causes of HBV infection and why these causes occur. Table 20-36 Causes Why Exposure to infected blood and Sharing of needles among IV drug abusers body fluids Sharps exposure Accidental blood spray Contact with blood by ungloved hands Unprotected sex A mother passing it to her unborn child Transfusion of blood and blood Exposure to infected blood and body fluids! products Screening techniques have drastically reduced the possibility of transmission, but there are no guarantees Hemodialysis Cross-contamination via contaminated needles and instruments Exposure through open wound sites Exposure through blood transfusions Source: Created by author from References #3 and #5. Signs and symptoms and why Table 20-37 shows signs and symptoms and rationales associated with HBV infection. e148 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Table 20-37 Signs and symptoms Why Fatigue Most common symptom and worse after activity The exact cause is unclear but seems to be related to the disease process and other factors, such as stress, anxiety, and sleep disturbance Fever Immune response to infectious disease Nausea and vomiting Usually associated with changes of smell and taste Decreased bile delivered to the intestine can result in nausea because bile acids are needed to digest fat Loss of appetite (anorexia) Related to the nausea and vomiting Steatorrhea (fatty stool) Decreased bile delivered to the intestine Jaundice (icterus) The liver has decreased capacity to absorb bilirubin from the blood, resulting in hyperbilirubinemia (too much bilirubin in the blood). Bilirubin then begins to be deposited in the tissues, causing a yellowish discoloration Itching Accumulation of bile components in skin tissue Dark urine Excess bilirubin in the blood is excreted by the kidneys Clay-colored stool The liver has decreased capacity to absorb bilirubin from the blood; therefore less bilirubin enters the intestines to help form the color of the stool Abdominal pain Tender liver Abdominal swelling Accumulation of fluid in the abdominal cavity. (ascites) Usually occurs in chronic hepatitis (Fig. 20-12) Source: Created by author from References #1 and #5. Ǡ Figure 20-12. A patient who has presented with a distended abdomen due to ascites and ↑ vascularity. (Photo generously provided by the CDC.) CHAPTER 20 ✚ Infectious Diseases e149 CASE IN POINT An EMT (emergency medical technician) working an MVA (motor vehicle accident) scene chooses not to wear gloves because the victim is a decent-looking young lady appearing to be free from infec- tious disease. He starts the IV line and receives a needle stick because the victim is hypoxic and combative (think head injury). He later discovers the victim is infected with HBV and after testing, so is he. Unfortunately, his pregnant wife tested positive (due to exposure to body fluids, semen from her husband during intercourse), and their newborn baby girl was positive as well (transmission from the mother while in utero). Quickie tests and treatments Tests include: ț Hepatitis panel to determine the type of hepatitis, the degree of immunity and communicability (degree to which the client’s blood and/or body fluids can infect others). In other words, am I immune or am I still in active disease and contagious to others? ț Liver profile to determine the amount of liver damage and liver func- tion. The profile includes these measurements: aspartate transaminase (AST, SGOT), alanine transaminase (ALT, SGPT), alkaline phosphatase (alk phos), gamma-glutamyltransferase (GGT), and bilirubin. Treatment includes: ț Antivirals. ț Interferon to enhance the immune system and inhibit viral replication (reproduction). ț Supportive care and symptom relief. ț HBV immune globulin for infants of HBV-positive mothers. ț Liver transplantation. ț Rest is extremely important. Pregnant women cannot take antivirals or interferon, and many clients may not complete treatment due to undesirable side effects of both classes. Prevention includes giving the HBV vaccine to all health care workers, all dialysis clients, and all infants. Also, clients should: ț Avoid razors, nail clippers, and toothbrushes used by others. ț Avoid tattoo parlors (equipment may not be sterile and/or free from infectious diseases such as HBV). ț Practice abstinence (no sex) or use condoms. What can harm my client? ț Alcohol (hard on the liver) ț Acetaminophen or acetaminophen-containing products (hard on the liver) ț Sedatives. (impaired liver function may lead to ↓ metabolism of certain medications) ț Any hepatotoxic (toxic to the liver) drug. ț Strenuous activities. Gloves do not guarantee protection from HBV, but if worn, can sub- stantially reduce the risk of infec- tion from HBV if the health care worker receives a stick. During a stick, the infected blood on the needle is essentially wiped off as the needle travels through the glove, drastically reducing the amount of infected blood on the needle. This substantially reduces the viral count of the infected blood. Therefore, the health care worker is inoculated with a viral count that may be too low to cause illness (e.g., saliva has a low viral count, rendering it noninfec- tious). Remember, the HBV vaccine helps to protect against HBV! AST and SGOT are the same thing. ALT and SGPT are the same thing. e150 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review If I were your teacher, I would test you on . . . ț What is it? ț Signs and symptoms and why. ț Causes and why. ț Those who are at high risk of becoming infected with the virus or spreading it. ț Prevention with examples of primary, secondary, and tertiary prevention. See Hurst Hint. ț Treatments. ț Complications. ț What can harm my client? ✚ Hepatitis C What is it? Hepatitis C (HCV) is one of the five hepatitis viruses that infect the liver. The symptoms and illness are usually much milder than those of HBV. According to the CDC, 80% of those with HCV have no signs or symptoms. This virus can cause chronic infection and/or liver disease, which may lead to the need for a liver transplant or death. What causes it and why Table 20-38 shows the causes of HBV disease and why these causes occur. Table 20-38 Causes Why Exposure to infected blood Needle sharing among IV drug abusers is the and body fluids most common mode of transmission Occupational exposure to blood Transmission through sexual contact is uncommon, with an estimated chance of 5%, but not impossible! Transmission from mother to unborn baby is also uncommon, with an estimated chance of 5%, also not impossible! Transfusion of blood and Exposure to infected blood and body fluids! blood products Screening techniques have drastically reduced the possibility of transmission, but there are no guarantees Hemodialysis Cross-contamination via contaminated needles and instruments Exposure through open wound sites (don’t forget those access sites) Exposure through blood transfusions Organ transplantation Exposure to blood and body fluids! Source: Created by author from References #2 and #3. At-risk populations include the sex- ually promiscuous, IV drug abusers, prisoners (they give each other homemade tattoos with nonsterile equipment), those who require repeated transfusions (e.g., hemo- philiacs), staff and residents of institutions (e.g., developmentally handicapped or mentally ill). Family members of chronically infected clients have a smaller but appreciable risk. Examples of primary prevention for hepatitis B include universal pre- cautions and all aspects of preven- tion, including the HBV vaccine. An example of secondary prevention is screening for infection, using blood tests. Tertiary prevention includes treatments and avoidance of what will harm my client. Regarding Hepatitis C: Many people are asymptomatic and unaware of the infection until it’s diagnosed incidentally or complications arise from chronic infection. CHAPTER 20 ✚ Infectious Diseases e151 Signs and symptoms and why Table 20-39 shows signs and symptoms and rationales associated with HCV infection. Table 20-39 Signs and symptoms Why Fatigue Most common symptom and worse after activity The exact cause is unclear but seems to be related to the disease process and other factors such as stress, anxiety, and sleep disturbance Myalgia (muscle pain) Immune response to infectious disease commonly results in muscle pain and fatigue Jaundice The liver has decreased capacity to absorb bilirubin from the blood, resulting in hyperbilirubinemia (too much bilirubin in the blood). Bilirubin then begins to be deposited in the tissues, causing a yellowish discoloration. This is a late sign in chronic infections Dark urine Excess bilirubin in the blood is excreted by the kidney Later on in chronic infections Abdominal pain Tender liver Loss of appetite (anorexia) Related to the nausea and vomiting Nausea and vomiting Usually associated with alterations of smell and taste Decreased bile delivered to the intestine can result in nausea because bile acids are needed for fat digestion Pruritus Accumulation of bile components in skin tissue Source: Created by author from Reference #5. Quickie tests and treatments Tests include: ț Hepatitis panel to determine the type of hepatitis. (The whole panel is usually ordered, because symptoms of HBV and HCV are similar.) ț Liver profile to determine the amount of liver damage and liver func- tion. The profile includes these measurements: aspartate transaminase (AST, SGOT), alanine transaminase (ALT, SGPT), alkaline phosphatase (alk phos), gamma-glutamyltransferase (GGT), and bilirubin. Treatments include: ț Interferon to decrease the chance of chronic infection; however, chronic infection does result in most clients. ț Symptomatic treatment for myalgia, nausea, vomiting, and pruritus. Unlike HBV, HCV does not have a vaccine. Prevention includes: ț Not sharing personal items, such as toothbrushes, razors, or nail clippers. ț Avoiding tattoos. ț Practicing abstinence or using a condom. (HCV is less likely to spread through sexual contact.) [...]... intestines e170 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Ǡ Figure 2 0-1 5 Hookworm in intestinal mucosa (Photo generously provided by the CDC.) What causes it and why Table 2 0-5 9 shows the causes of this infection and why these causes occur Table 2 0-5 9 Causes Why A common species, Ancylostoma duodenale is found in southern Europe, northern Asia, northern Africa, and parts of South America Either... through the stool and exit the body (Fig 2 0-1 6) ǡ Figure 2 0-1 6 Adult tapeworm (Photo generously provided by the CDC.) e172 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review People at risk for tapeworm infection are those who prefer to eat raw or undercooked meat What causes it and why Table 2 0-6 1 shows the causes of this infection and why these causes occur Table 2 0-6 1 Causes Why Eating raw or undercooked... adults >60 years of age (Continued) e173 e174 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Table 2 0-6 3 (Continued ) Types Why West Nile virus First recognized in the United States in 1999 Found in Africa, Middle East, Russia, Indonesia, and India Birds are the main host Spread from person-to-person by blood transfusions, breast-feeding, and organ transplants Symptoms appear in 5–15 days Western... causes it and why Table 2 0-5 1 shows the causes of this infection and why these causes occur Table 2 0-5 1 Causes Why Drinking contaminated water Waterborne transmission Eating something that has been contaminated by the feces of someone infected with Giardia lamblia Transmitted through the fecal–oral route (Continued) e164 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Table 2 0-5 1 (Continued ) Causes... the rash is allergic or the mono/penicillin-related rash e160 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review ✚ Rotavirus What is it? This virus causes acute infectious diarrhea in young children and in adults who are exposed to infected children What causes it and why Table 2 0-4 7 shows the cause of this infection and why this cause occurs Table 2 0-4 7 Cause Why Exposure to individual infected... the body (usually the back or side) that seem to be following a path (dermatome), think shingles e162 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Signs and symptoms and why Table 2 0-5 0 shows the signs and symptoms and rationales associated with this infection Table 2 0-5 0 Signs and symptoms Why Tingling, burning, itching, and pain (can be severe) Virus has been dormant along the dorsal root... Use of a large-bore needle or a large knife blade increases the risk of spreading HIV ț Because most clients do not know they are infected with HIV/AIDS, standard precautions should be used when caring for all clients ț Clients do not die from HIV but from the opportunistic infections related to the impaired immune system e154 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Table 2 0-4 2 (Continued... by author from Reference #3 e165 e166 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Quickie tests and treatments ț Stool cultures are used to detect Cryptosporidium More than one sample may be needed because the organism can be difficult to detect ț Disease can be self-limited, but may require treatment with oral nitazoxanide Hand-washing is the key to prevention ț Cryptosporidium can lead... 2 0-4 3 Causes Why Exposure to someone who has the flu The flu is transmitted via respiratory droplets and direct contact, such as touching or kissing Source: Created by author from Reference #1 e155 Hematopoiesis means to make blood cells The tissues that make the blood cells are called hematopoietic cells e156 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Signs and symptoms and why Table 2 0-4 4... attacks part of the nerves, resulting in muscle weakness and even paralysis If the muscles that control breathing become paralyzed, the client will require a ventilator The syndrome usually occurs after a mild infection, surgery, or immunization Please don’t immunize a client who has had GBS in the past! e158 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review What causes it and why Table 2 0-4 5 shows . symptoms and why Table 2 0-3 7 shows signs and symptoms and rationales associated with HBV infection. e148 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Table 2 0-3 7 Signs and symptoms Why. these organisms can take over and cause disease (Fig. 2 0-1 3). Ǡ Figure 2 0-1 3. This image reveals the presence of both the human T- cell leukemia type-1 virus (HTLV-1) and the human immunodeficiency virus (HIV). (Photo. #1. e156 MARLENE HURST ✚ Hurst Reviews: Pathophysiology Review Signs and symptoms and why Table 2 0-4 4 shows the signs and symptoms and rationales associated with flu. Table 2 0-4 4 Signs and symptoms Why