Nelson - Ch. 201 Vibrio

Question 1

V. cholerae is a G- comma shaped bacillus subdivided into serogroups by

Answer 1

O antigen

Question 2

The only V cholerae serogroups associated with epidemics

Answer 2

O1 and O139

Question 3

V cholerae serogroup that caused the most extensive pandemic

Answer 3

V. cholera O1 El tor

Question 4

Main modes of transmission of V. cholerae

Answer 4

Consumption of contaminated water and undercooked shellfish

Question 5

Risk factors for severe V cholera infection

Answer 5

1) Blood type O 2) Decreased gastric acidity 3) Malnutrition 4) Immunocompromised state 5) Absence of local intestinal immunity

Question 6

Cholera toxin consists of 1 active A subunit and 5 binding B subunits. ___ subunit stimulates adenylate cyclase.

Answer 6

A

Question 7

Cholera toxin consists of 1 active A subunit and 5 binding B subunits. ___ subunit binds to the GM1 ganglioside receptors in the intestine.

Answer 7

B

Question 8

Hallmark of cholera

Answer 8

Painless rice-watery diarrhea with a fishy smell

Question 9

Most severe form of cholera, cholera graves, results when purging rates of ___ occur

Answer 9

500-1000mL/hr

Question 10

Gold standard for diagnosis of cholera

Answer 10

Microbiologic isolation

Question 11

Selective medium for cholera

Answer 11

TCBS

Question 12

Typical motility of V. cholerae and mode of microscopy for demonstration

Answer 12

Darting, dark-field in wet mount of rice-watery stool

Question 13

Mainstay of therapy for cholera

Answer 13

Rehydration

Question 14

Preferred hydration in patients with cholera

Answer 14

Rice-based ORS; shown to be superior to standard ORS in children and adults

Question 15

T/F Antibiotics for cholera shorten duration of illness, decrease fecal excretion of vibrios and volume of diarrhea, and reduce fluid requirement during hydration

Answer 15

T

Question 16

Pharmacologic treatment for cholera that increases compliance

Answer 16

Doxycycline