Internal Medicine

0521779407-10 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 18:40

Infectious Diarrheas 827

specific therapy

■empiric antimicrobial therapy without additional evaluation:

➣moderate-to-severe travelers’ diarrhea

➣8 stools/d, with blood or pus, fever

➣if bacterial diarrhea suspected by clinical features and/or pos-

itive fecal occult blood or fecal leukocytes; not for Shiga toxin-

producing E. coli or C. difficile

➣if Giardia suspected and≥2 wk duration (metronidazole)

■nonspecific (not for patients with febrile dysentery or Shiga toxin-

producing E. coli):

➣opiates and derivatives (decrease intestinal motility)

loperamide (Imodium) – reduces number of stools

diphenoxylate-atropine (Lomotil) – less expensive, but has

central opiate and adverse cholinergic effects

➣bismuth subsalicylate for vomiting and mild to moderate acute

diarrhea

➣specific antimicrobial therapy (treatment of choice listed):

Campylobacter jejuni(most common pathogen in immuno-

competent patients with bacterial diarrhea)

fluoroquinolones

Campylobacter fetus(immunocompromised patients)

ampicillin+gentamicin IV

Shigella(treat all moderate and severe dysentery)

fluoroquinolones

Salmonellagastroenteritis, uncomplicated

no antibiotics

Salmonellagastroenteritis, severe, or in immunocompro-

mised or elderly

trimethoprim-sulfamethoxazole (if susceptible) or cipro-

floxacin

enteric (typhoid) fever

fluoroquinolones

if shock or deteriorating mental status – dexamethasone

(before antibiotic)

Shiga toxin-producing E. coli (including O157:H7)

antimotility agents and antibiotics should be avoided

enterotoxigenicE. coli(traveler’s diarrhea)

consider empiric therapy with fluoroquinolones, or rifax-

imin

enteropathogenic E. coli

fluoroquinolones

Clostridium difficile