an approach to evaluation and management of acute diarrhoea

1. Acute infectious diarrhea
Food poisoning
&
Acute gastroenteritis

2. Causes
 Food-poisoning- preformed exotoxin
 S.aureus, B,cereus, C.perfringens
 Non-inflammatory- viral/enterotoxin- proximal
small intestine
 Viral- rotavirus, norwalk-like virus
 Bacteria- ETEC, V.cholerae
 Parasite- Giardia
 Inflammatory- cytotoxin/invasive-
distal small intestine or colon
 Parasite- E.histolytica
 Bacteria- Shigella, Salmonella, EHEC/EIEC,
Campylobacter, Yersinia, V.parahemolyticus

3. Evaluation
 History-
 Duration- >2 weeks is chronic
 Fever- suggests invasive disease
 Stool- dysentery-inflammatory, rice water-Cholera
 Abdominal pain- inflammatory>non-inflammatory
 Tenesmus- proctitis- Shigellosis/Amoebiasis
 Vomitting- s/o food poisoning
 Prior antibiotic use- C.difficile-pseudomembranous colitis
 Examination-
 Fever, e/o dehydration- tachycardia, hypotension, weight loss
 Stool examination-
 For WBC- presence s/o inflammatory cause

4. Management
 Dx-
 Clinical & stool examination
 Assess hydration status
 Treatment-
 No specific dietary restrictions or recommendations
 Continue breast-feeding
 ORS- nimbu-paani, rice water, commercial preparations
 IV fluids- Ringer’s lactate- vomiting, ileus, altered sensorium
 Antiemetics- metoclopramide, domperidone
 Antibiotics- dysentery, pseudomembranous colitis, immunosuppressed
 Antimotility agents- Loperamide, not in children
 Prevention-
 Sanitation & hygiene
 Vaccine- rotavirus, typhoid, cholera

5. ORS constituents- per liter water
NaCl- 3.5 gm
NaHCO3- 2.5 gm
KCl- 1.5 gm
Glucose-20 gm

6. Food poisoning
 Due to preformed enterotoxin
 Abrupt onset
 S.aureus-
 1-6 hours, intense vomiting with diarrhea
 C.perfringens-
 6-12 hours, profuse diarrhea with cramps & nausea
 B.cereus-
 Reheated rice- 1-6 hours, severe vomiting with diarrhea
 Meat/gravy- 6-12 hours, severe diarrhea with nausea/vomiting
 Rx- supportive- antiemetics & ORS

7. Escherichia coli
 Gram –ve bacillus
 Normal commensal in human gut
 Virulent types-
 Enterotoxigenic- leading cause of watery diarrhea,
most common cause of travellers’ diarrhea
 Enteropathogenic- diarrhea with mucus
 Enteroinvasive- profuse diarrhea with fever
 Enterohemorrhagic- dysentery, can cause HUS
 Enteroaggregative- watery diarrhea
 Rx- supportive,
fluoroquinolones shorten duration

8. Cholera
 Caused by bacteria V.cholerae
 Primarily affects small-intestine
 People with O blood group more affected,
carriers of cystic fibrosis are protected
 Toxin leads to cAMP activation causing
secretion of water, Na, K, Cl & HCO3
 Causes profuse diarrhea (rice water),
with abdominal pain, ± vomiting

9. Management
 Dx-
 Clinical
 Stool enrichment/culture
 Rx-
 ORS, ± IV fluids
 Antibiotics shorten duration- Doxycycline, cotrimoxazole
 Prevention-
 Whole cell inactivated oral vaccine
 Sanitation
 Proper sewage disposal
 Water treatment/purification

10. Salmonella typhi
 A gram –ve bacillus
 Causes diarrhea with mild fever or TYPHOID-
enteric fever
 Stages- each lasting ~1 week
 1- mild fever, relative bradycardia, malaise, leucopenia,
blood culture +ve, Widal test -ve
 2- high fever, Rose spots on trunk, delirium, bradycardia,
diarrhea (occasionally constipation), HSmegaly,
blood culture/Widal test +ve
 3- high fever, delirium, complications- hemorrhage, perforation,
peritonitis, cholecystitis, metastatic abscess
 4- resolution/defervescence

11. Management
 Dx-
 Clues- relative bradycardia, coated tongue, lymphopenia, splenomegaly
 Blood/marrow/stool culture
 Widal test- Ab against O/H Ag- preferably 4-fold rising titres
(high false +ve rate due to cross-reactivity with
other Salmonella species & malaria)
 Rx-
 Antibiotics- 3rd
/4th
generation cephalosporin- oral/IV x 10 days
 Supportive- rehydration
 Surgery, as required for complication- hemorrhage, perforation
 Prevention-
 Sanitation & hygiene
 Vaccine- live oral/injectable polysaccharide, booster every 5/2 years