Exam 11: Travelers Diarrhea: Identifying the Causative Agent

What is the mechanism of action of the aminoglycosides?

When IgG is cleaved by papain, which of the following fragments appear?

A new class of pathogen appears, causing pneumonia. It appears to be some sort of budding yeastlike organism with chitin in the cell wall, but the nucleus is not membrane bound and the protein synthetic equipment appears to be procaryotic. Which of the following antimicrobial agents is most likely to be effective?

In which one of the following fungal scalp infections is hair loss most likely to be permanent?

A burn patient has an infected area with odiferous, blue-green pus. What is the most likely causative agent?

A 37-year-old woman who is on chemotherapy is admitted in respiratory distress. She had signs of focal central nervous system (CNS) lesions early in the day and is now in a comatose state. Both the CNS and pulmonary biopsies show dichotomously-branching (at an acute angle), septate hyphae. What is the most likely underlying condition?

$beta-lactam$ drugs bind to penicillin-binding proteins to halt the synthesis of peptidoglycan. Where are these proteins located?

A 22-year-old woman presents with vaginal itching and erythema as well as a discharge which is thick and white. External erythema is also present with discrete pinpoint lesions off the edge. The discharge pH is 4.7 (normal). Amine test is negative as is the genetic probe test for Neisseria. What is the most likely cause?

A patient presents with an inflamed itchy groin area. What antifungal would work as long as it is a dermatophyte but might make it worse if it is a yeast infection?

Corynebacterium diphtheriae is isolated from a patient with pharyngitis. What is the best predictor that the strain is pathogenic?

A 19-year-old pregnant student presents at her health service allergy clinic with rhinorrhea, sneezing, itching, and conjunctivitis. A RAST test finds IgE antibodies to ragweed antigens. A characteristic of this condition is

An otherwise healthy 23-year-old woman presents with urinary urgency and frequency along with pain on micturition. What is the most likely causative agent?

The parents of an 18-month-old girl appear at the emergency department of a hospital with their daughter, who had an abrupt onset of vomiting and incidences of watery diarrhea. The symptoms began 2 days previously at her day care center. She refuses to eat or drink and is very lethargic. What property of the infectious agent causing these symptoms allowed the preparation of a vaccine that could have prevented them?

Viral proteins that disrupt calcium homeostasis within infected cells are

An outbreak of respiratory disease that leads to pneumonia occurs in a nursing home. It is characterized by an interstitial x-ray pattern and both amantadine and zanamivir are effective treatments. What is the causative agent?

A patient who is diabetic and has been in the hospital twice in the last year presents with a boil on his neck. You drain it, but because of his hospitalizations you realize that there is a good chance that it could be a drug-resistant strain and order direct Gram stain cultures, as well as susceptibility testing and anaerobic culture. The preliminary report comes back with Gram-negative cocci in clusters. This puzzles you, so you call the lab supervisor who realizes the stain was done by a new lab person. It turns out to be Staphylococcus aureus. What mistake in the Gram stain did the new person most likely make to produce pink cocci with no hint of purple?

A 48-year-old woman who presents with muscle weakness and a thymoma is suspected of having myasthenia gravis. If correct, lab tests should show autoantibody against

Which immunoglobulin has the highest level in a normal 1-day-old infant?

A 23-year-old who just returned from a 2-week missionary trip to rural Haiti presents with a 2-day history of watery diarrhea. What is most likely causing his problem?

A 24-year-old Peace Corps worker is sent back to the United States from East Africa because he has had a very high fever. African sleeping sickness is diagnosed. How is it transmitted?