Case Studies
Case 2 1. What should your answer to Heather's question be?2.Heather says that because she had a flu shot last year she's going to skip it this year. Respond with an explanation. 3. What is the difference between "antigenic drift" and "antigenic shift"? 4. What is the difference about the vaccine from year to year? Who decides what form it will take every year? 5. Susan wants to know why you don't have to get other vaccines annually. 6. Another friend, Sam, says that even though she had the flu shot last year, she got terribly sick with the stomach flu over Thanksgiving break and missed most of her vacation. What is your explanation for this?
1. No. The vaccine for influenza consists of killed influenza virions; it will not cause even a mild case of the flu in any of those receiving the vaccine. 2. Best protection comes from getting a new flu vaccination every year. The influenza vaccine becomes less effective over the course of time, as a result of changes in the virus. 3. Antigenic drift- the surface antigen of the influenza viruses in nature are constantly changing in small ways with regard to their chemical composition. Antigenic shift- more abrupt change in antigen composition. 4. strains of virus that are included in the vaccine dose may be different from year to year. The Centers for Disease Control and Prevention (CDC) maintains a worldwide surveillance system that monitors viruses 5. Not all infectious microorganisms change their surface antigens the way influenza does. Changes in surface antigens originate in changes (mistakes) in the genetic material of an organism. 6. influenza virus only causes symptoms in the respiratory tract. Intestinal symptoms are not a feature of influenza.
Case 1 At the Mount Union hospital, a 5-year old white male child in good general health and physical condition was presented at the Saturday walk-in clinic by his mother. He was brought in because he had a fever, was cranky and had complained of a sore throat for about 24 hours. On physical examination by the attending resident, the patient had a fever of 39.3C, and he had considerable swelling and drainage of the pharynx and in the conjunctivae. His tonsils were enlarged and coated with a white patchy exudate. He had a red throat and swollen anterior cervical lymph nodes. His ears were clear. His chest sounded clear and he had no additional remarkable findings on routine examination. 1. What would be your presumptive diagnosis for this child? Why? 2. What diagnostic testing would be indicated to follow this exam? 3. What is the most likely treatment for this illness? Why is it important? What could happen if not treated? 4. What specific factors of this case allowed you to make a presumptive diagnosis?
1. Patient had streptococcal pharyngitis. Classical symptoms, pus on tonsil and pharynx, fever. 2. Tests should include a culture and sensitivity from throat swab on blood agar plate and/or a rapid strep antigen test. 3. Treatment with penicillin or erythromycin for 10 days; treatment is important to prevent scarlet fever and rheumatic fever with their associated heart problems and kidney problems that could occur later in life. 4. Clear lungs, pus on tonsils and pharynx, fever and history.
Case 10 A 68-year old patient with Alzheimer disease was brought to the emergency room by the staff of a local nursing home. He presented as lethargic with a sallow complexion. He had an admission temperature of 102.4F and a respiratory rate of 33/minute. During respiration, the right side of his chest moved better than the left. He showed dense consolidation of the lower lobe of the left lung on physical exam. A sputum sample revealed blood and a greenish color. A chest x-ray showed tight consolidation of the left lung with evidence of formation of cavities in the lung tissue from cytotoxic damage. The patient complained of chills in the exam room, combined with his fever. A smear of his sputum demonstrated no acid-fast bacteria but did show numerous gram-negative bacilli. 1. What is your presumptive diagnosis for this case? 2. What evidence could the sputum give for this case? 3. Is the reduced respiration rate and unequal chest movement indicative of the pathology? 4. Is this a bacterial or viral disease?
1. bacterial pneumonia caused by Klebsiella; cytotoxic damage to lungs 2. sputum would show Gram-negative, heavily encapsulated rods. When grown on MacConkey agar this organism is very mucoid and slimy due the capsule production. 3. Yes, damage to the lungs and the heavily consolidated inflammation would lead to these observable changes. 4. bacterial; warrants use of antibiotics (amino glycosides).
Case 9 A 22-year old male college student was presented at the ESU health clinic. He looked tired and pale. He presented because of high fever and chest pain. He was afraid he was having a heart attack (bad week of exams). He was examined immediately by the PA and an EKG strip was run. He had no evidence of acute heart problems. The attending physician visited the patient. He obtained the following history from the past 36 hours. The patient had a tight cough. He had significant muscle aches and pains. He had a bad headache and had had fevers of 101-103F. The physician ordered a chest x-ray. It did not show any significant consolidated inflammation suggestive of pneumonia. The patient showed significant nasal drainage and a moderately tight, but productive cough on physical exam. He had a fever of 101F and generally inflamed mucous membranes. A rapid Strep test showed no evidence of Streptococcal infection and his tonsils and adenoids had been removed. 1. What is the most likely diagnosis for this patient? On what do you base this diagnosis? 2. What secondary infection problems should be monitored? 3. What is the preferred treatment for this disease?
1. influenza; fever, moderate pain in lungs (chest), headache, no pneumonia, tight productive cough, no evidence of Strep 2. bacterial pneumonia may follow severe influenza 3. fluids, bed rest, fever-reducing medicine
