diarrhea

• Acute < 2 wk• Invasive vs noninvasive• Invasive: fever,dysentery,severe abdominal

pain, wbc-rbc in stool• Stool c/s in :suspected invasive,

immunocompromise host, protracted diarrhea > 3 day

• Stool for parasite : duration > 7 day

• Empirical antibiotic : 3-5 day– Ciprofloxacin 1000 mg /day– Norfloxacin 800 mg/day– Levofloxacin 500 mg/day– Azithromycin 500 mg/day

(ped,pregnancy,campylobacter in thai)

• Persistent diarrhea– Metronidazole 250 mg tid :7-10 day(rx:giardia)

Invasive

• Campylobacter• Samonella• shigella• Vibrio parahaemolyticus• Enterohemorrhagic Escherichia coli

Campylobacter

• chicken• Resist to ciprofloxacin in Thailand 80%• Guillain-Barre syndrome• Rieter syndrome

Samonella

• Sepsis in immunocompromised host• ABO: in age< 3 mo,> 50yr AIDS, malignancy• ABO may prolong carrier stage• Reiter syndrome

shigella

• S.dysenteriae : ABO to all +ve culture,prevent outbreak

• Reiter syndrome• Seizure in children

Vibrio parahaemolyticus

• Raw fish• Self limited

E.Coli O 157:H 7

• Dysentery ,no or low grade fever• ABO:risk HUS• meat

Toxin-induced bacterial gastroenteritis

• Non invasive (bacterial and viral)• Clinical: watery,minimal fever,little or no

abdominal pain,no wbc-rbc in stool

Non invasive

Vibrio species

• Except: V.parahaemolyticus• V.gravis (cholera) :rice water, > 1 Liter/hr• V.vulnificus: contact sea water with open

wounds:hemorrhagic bleb+septic shock,MR 50%

Scomboid fish

• Tuna,Mackerel• Heat stable• Produce histamine ,improper refrigeration• Metallic, bitter or peppery taste

Ciguatera fish poisoining

• Ciguatoxin neurotoxin• Odorless,taseless• GI symptoms and constellation of neurological

symptoms• Tingling around mouth, painful teeth, burning

feet,CNS chage;ataxia,weakness,vertigo,confusion

• Misdiagnosis :AGE with hyperventilation syndrome

Enterotoxigenic Escherichia coli(ETEC)

• Most common cause of traveler’s diarrhea

Clostridium difficile • Normal gut flora• Board spectrum ABOovergrowthproduced

toxin,develops during ABO administration or within 2 wk of discontinue

• Toxin Aattract neutrophil and monocyte• Toxin Bdisrupt colonic epithelial cell• Clinical : same as invasive group• 25% better when stop ABO 48-72 hr• Rx: first line oral or iv metronidazole,if severe

oral vancomycin

Viral gastroenteritis

• Adult: norovirus• Children: rotavirus• Dx in adult: one of exclusion

Diarrhea in AIDS• 20-25% multiple pathogens• Cryptosporidium and isospora belli persist in CD4

< 200 cell/mm3

• MAC and CMV in CD4 <100 cell/mm3

• samonella esp. S.typhimurium high risk bacteremia

• Consider strongyloids in any immunocompromised pt whosudden clinical deterioration,eosinophillia,polymicrobial sepsis, meningitis, adynamic ileus

Diarrhea in AIDS

Diagnosis• H/C : in MAC, samonella, CMV• CBC: eosinophillia in stronyloides, Isospora• Rectal biopsy: CMV inclusion body with clear

halo

Diarrhea in AIDS

• SE HAART: PInelfinavir, lopinavir/rotinavir• Rx– CMV:ganciclovir,foscarnet– MAC:clarithromycin,azithromycin;poorly response

to rx,death within 6-8 mo after dx– Strongyloid:ivermectin 200 mcg/day 1-2

day,thiabendazole 50 mg/kg/day 2 day, if disseminated rx for at least 5 day

Traveler’s diarrhea

• ETEC most common• Mild,non dysentery,single dose of

ciprofloxacin 750 mg PO combination with loperamide

• High fever,bloody stools,typical invasive picture, norfloxacin 400 mg bid or ciprofloxacin 500 mg for 3 day