Quiz diarrhea
�
Entamoeba histolytica
• Trophozoite and cystic form• Invasive produce colonic ulceration• <1% spread outside the intestine :liver ,brain
infection, pleural or pericardial effusion• Complication: GI bleeding, toxic megacolon,
intussusception, stricture,perforation• Stools: blood-streaked mucus• Ab-based enzyme immunoessay sens and spec
95%
• Rx : paromomycin, iodoquinol, diloxanide furoate
• Severe symptoms:metronidazole750 mg tid x10 day
Enterobius vermicularis
• Pinworm or seatworm• Natural host: human• Noninvasive• Perianal tingling or itching at night• Cellophane tape test• Rx empirically all other familial member• Albendazole 400 mg once,2nd dose at 2 wk
later
Giardia
• Backpacker’s diarrhea• Pt with decreased gastric acid: susceptible to
Giardia infection• Proximal bowel,superficial invasion of the
mucosa• Symptoms:from malabsorption• Abdominal distension, colicky pain, flatulence,
frequency explosive diarrhea
Giardia
• Acute infection: stool exam sens>95%• Chronic infection: ELISA, DFA• Rx:metronidazole 250 mg tid x7 day
Ascaris lumbricoides• eggs are swallowed invade intestine
mucosalungsthe bronchial tree swallowing to the small intestine
• adult worms in the small intestine: no symptoms• nonproductive cough ,substernal
discomfort,dyspnea,fever,eosinophilia • Rx:Albendazole (400 mg once), mebendazole
(500 mg once), or ivermectin (150–200 g/kg once)
5 micron
20 micron
Coccidial infection
Cryptosporidium• most common cause of chronic diarrhea in
AIDSIsospora belli• OI in AIDS
Coccidial infection
• Non invasive• Mild to profuse watery diarrhea• Dx:oocysts in stool, acid fast stain ,EISA• Cryptosporidium 5 micron, Isospora 20 micron• Cryptosporidium Rx:Self-limited in
immunocompetent, AIDS:HAART• Isosporisis: TMP-SMX
Cyclospora
Cyclospora cayetamemsis
• Acute explosive watery diarrhea and abdominal cramps ,subside in 1-3 day
• Followed by intermittent mild diarrhea and marked anorexia and fatigue
• Dx: modified acid fast stain 8-10 micron,DDx cryptosporidium
• Rx:TMP-SMX
Strongyloides stercoralis• uncomplicated strongyloidiasis: asymptomatic• Immunocompromise host: Colitis, enteritis, or
malabsorption • In disseminated strongyloidiasis:GI,lungs,CNS , peritoneum,
liver, and kidneys• Gram-negative sepsis, pneumonia, or meningitis may
complicate• Dx: larvae in stool• Rx:Ivermectin 200 g/kg daily for 2 days, albendazole 400
mg daily for 3 days• For disseminated strongyloidiasis rx at least 5–7 days or
until the parasites are eradicated.
Tenia
• Intestinal infections with T. solium may be asymptomatic
• In cysticercosis: cysticerci can be found anywhere in the body but are most commonly detected in the brain
• Dx: proglottid in stool• Rx:A single dose of praziquantel (10 mg/kg) is
highly effective