Question 1

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?

Accepted Answer

A)   Platelet-activating factor
B)   Interferon-γ
C)   Interleukin-1
D)   Tumor necrosis factor
E)   Prostaglandin E2 B

Question 2

Which of the following is the most common form of herpesvirus-induced eye infection?

Accepted Answer

A)   Blepharitis
B)   Conjunctivitis
C)   Iridocyclitis
D)   Keratitis
E)   Retinitis D

Question 3

Which of the following is a preventable cause of blindness in Africa?

Accepted Answer

A)   Giardiasis
B)   Onchocerciasis
C)   Filariasis
D)   Cryptosporidiosis
E)   Schistosomiasis B

Question 4

Schistosoma mansoni infection causes liver changes that present histologically as

Accepted Answer

A)   granulomas that also contain eosinophils
B)   abscesses
C)   suppurative cholangitis
D)   centrolobular necrosis of liver cells
E)   centrolobular fibrosis

Question 5

Mycobacterium avium intracellulare infection in AIDS patients typically begins in the

Accepted Answer

A)   nasal cavity
B)   lungs
C)   esophagus
D)   small intestine
E)   liver

Question 6

Which African disease is complicated by elephantiasis of the legs?

Accepted Answer

A)   Giardiasis
B)   Onchocerciasis
C)   Filariasis
D)   Cryptosporidiosis
E)   Schistosomiasis

Question 7

The diagnosis of malaria is best made by examining a

Accepted Answer

A)   biopsy specimen of the liver
B)   biopsy specimen of the spleen
C)   bone marrow biopsy
D)   blood smear
E)   serum sample for antibodies to plasmodia

Question 8

A 60-year-old man known to have diabetes mellitus was admitted to the hospital in ketoacidosis. He had a massive, invasive infection of the nasal sinuses. Biopsy disclosed fungal infection, which was most likely caused by

Accepted Answer

A)   Candida albicans
B)   Aspergillus fumigatus
C)   Mucor
D)   Histoplasma capsulatum
E)   Pneumocystis carinii

Question 9

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

Accepted Answer

A)   dilatation of the entire small intestine
B)   ulceration of the proximal small intestine
C)   ulcerations of the distal ileum
D)   multiple ulcerations partially covered with pseudomembranes
E)   perforation of the rectum

Question 10

Reiter syndrome, including the triad of conjunctivitis, polyarthritis, and genital lesions, occurs in men infected with which pathogen?

Accepted Answer

A)   Neisseria gonorrhoeae
B)   Treponema pallidum
C)   Chlamydia trachomatis
D)   Trichomonas vaginalis
E)   Haemophilus ducreyi

Question 11

Diarrhea caused by cholera toxin results from the action of this toxin on cells of the

Accepted Answer

A)   stomach
B)   small intestine
C)   cecum
D)   transverse colon
E)   rectum

Question 12

Lepromatous leprosy represents a form of disease that develops due to

Accepted Answer

A)   accelerated T-helper lymphocyte response
B)   accelerated cytotoxic T-cell response
C)   inadequate B-cell response
D)   hyperimmunity
E)   immunologic anergy

Question 13

Infection of the uterus following a "criminal abortion" performed in a "back alley" is most likely caused by

Accepted Answer

A)   anaerobic non-spore-forming bacteria
B)   spore-forming anaerobes
C)   pyogenic cocci
D)   coliform bacteria
E)   Neisseria gonorrhoeae

Question 14

Suppurative nail infection (paronychia) and abscesses of fingertips ("felons") are most likely caused by

Accepted Answer

A)   Escherichia coli
B)   Pseudomonas aeruginosa
C)   Haemophilus influenzae
D)   Neisseria gonorrhoeae
E)   Staphylococcus aureus

Exam 8: General Pathology of Infectious Diseases