Acute Diarrhoea in Children
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Direct answer
Acute diarrhoea kills children through dehydration, so assessment revolves around fluid status rather than the stool organism: WHO classifies dehydration as none, some or severe, and assigns Plans A, B and C — home fluids with continued feeding, oral rehydration with 75 mL/kg over four hours, or rapid intravenous rehydration. Every episode receives ORS plus zinc for 14 days, and feeding is never stopped. Dysentery — bloody, mucoid stool — is treated as bacterial (shigellosis above all) with an antibiotic, while antidiarrhoeal agents have no place in children.
What you must remember
- Dehydration assessment: general condition, eyes, thirst and skin pinch classify dehydration as none (Plan A), some (Plan B) or severe (Plan C); lethargy, inability to drink and a very slow pinch mean severe dehydration.
- Reduced-osmolarity ORS: the WHO formulation of 245 mOsm/L — sodium 75, chloride 65, glucose 75, potassium 20 and citrate 10 mmol/L; glucose-linked sodium absorption survives toxin-induced secretion, the basis of ORS.
- Plan B: ORS 75 mL/kg over four hours, reassessed and repeated. Plan C: intravenous Ringer's lactate 100 mL/kg — infants get 30 mL/kg in the first hour, then 70 mL/kg over five hours; older children 30 mL/kg in 30 minutes, then 70 mL/kg over two-and-a-half hours — switching to oral fluids early.
- Zinc: 20 mg elemental zinc daily for 14 days (10 mg under six months) — it shortens the episode and protects for months afterwards.
- Feeding: continue breastfeeding and age-appropriate feeding; avoid fruit juices and sugary drinks; extra meals after recovery aid catch-up growth.
- Dysentery: blood and mucus in stool, most often shigellosis, treated with azithromycin or ciprofloxacin per current national guidance; metronidazole for demonstrated amoebiasis.
- What to avoid: loperamide and other antimotility agents (ileus, CNS depression), unnecessary antibiotics in watery diarrhoea, and stopping feeds.
Common confusion
The commonest confusion is between ORS as treatment of dehydration versus of diarrhoea: ORS does not reduce stool volume (rice-based ORS modestly does in cholera); it keeps the child alive while illness runs its course. The second is persistent diarrhoea — beyond 14 days — which shifts the differential toward lactose intolerance, malnutrition, giardiasis and immunodeficiency. Third, vomiting need not block oral therapy: small frequent sips usually succeed, and intractable vomiting means intravenous or nasogastric rehydration — never "dry and starve".
Exam-focused takeaway
NEET-PG draws from a fixed pool: ORS composition and its glucose-sodium coupling, the zinc dose and duration, the plan-by-plan volumes, and the classification signs that assign plans. Vignettes give a child's condition, eyes, thirst and pinch and expect the plan; numbers questions expect 75 mL/kg over four hours and the Plan C rate split by age. Dysentery stems pair blood in stool with shigella and an antibiotic, and one-liners probe rotavirus as the commonest cause of severe dehydrating diarrhoea in young children.
Frequently asked questions
What is the composition of WHO reduced-osmolarity ORS?
Sodium 75, chloride 65, glucose 75, potassium 20 and citrate 10 mmol/L — a total osmolarity of 245 mOsm/L.
Why does ORS work despite secretory diarrhoea?
Glucose-coupled sodium absorption remains intact even in toxin-mediated secretion, so ORS drives water absorption regardless of stool losses.
What is the dose of zinc?
20 mg of elemental zinc daily for 14 days, halved to 10 mg in infants under six months.
How is severe dehydration treated?
Intravenous Ringer's lactate 100 mL/kg: infants get 30 mL/kg in the first hour and 70 mL/kg over five hours; older children get 30 mL/kg in 30 minutes and 70 mL/kg over two-and-a-half hours.
Which children need an antibiotic?
Those with dysentery (usually shigella), suspected cholera, proven protozoal infection or associated sepsis — watery non-dysenteric diarrhoea does not.