Chapter 08: Infections

Chapter 08: Infections

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

MULTIPLE CHOICE

1. Which of the following is the most common form of herpesvirus-induced eye infection?
2. Blepharitis
3. Conjunctivitis
4. Iridocyclitis
5. Keratitis
6. Retinitis

ANS: D, Herpesvirus most often causes keratitis, which can be classified as epithelial or interstitial.

2. Mycobacterium tuberculosis phagocytosed by macrophages in granulomas can be killed by endogenous nitric oxide (NO) after these macrophages become activated by T-helper cells. Which biologically active substance stimulates the formation of NO in macrophages?
3. Platelet-activating factor
4. Interferon-g
5. Interleukin-1
6. Tumor necrosis factor
7. Prostaglandin E2

ANS: B, CD4+ T-helper cells secrete interferon-g, which stimulates the macrophages to produce nitric oxide (NO), NO₂, and HNO₃. These bactericidal substances kill the tubercle bacilli in the cytoplasmic vacuoles of the macrophages.

3. Mycobacterium avium intracellulare infection in AIDS patients typically begins in the
4. nasal cavity
5. lungs
6. esophagus
7. small intestine
8. liver

ANS: D, Mycobacterium avium intracellulare infections usually begin in the small intestine, and may disseminate from there to the lymph nodes, spleen, and liver.

4. During a mini-epidemic of Shigella, a 5-year-old child from India became infected and died 3 days after the onset of diarrhea. The most prominent changes seen at autopsy were
5. dilatation of the entire small intestine
6. ulceration of the proximal small intestine
7. ulcerations of the distal ileum
8. multiple ulcerations partially covered with pseudomembranes
9. perforation of the rectum

ANS: D, Ulcerations of the colonic mucosa caused by Shigella are usually covered with pseudomembranes. These findings are not specific but correlate well with the clinical findings, which invariably include massive bloody, pus-containing diarrhea.