Pediatric Gastroenterology, Hepatology and Nutrition
Domain focus
Pediatric Gastroenterology, Hepatology and Nutrition tests vomiting, diarrhoea and dehydration, growth faltering, jaundice, liver disease and common nutrition deficiencies.
Core rules
- Bilious vomiting is malrotation until proven otherwise; obtain urgent surgical review and imaging.
- Pyloric stenosis presents at 3–6 weeks with projectile non-bilious vomiting, hunger and hypochloraemic metabolic alkalosis.
- Gastro-oesophageal reflux is usually physiological in infancy; avoid routine acid suppression without red flags.
- Celiac disease: check IgA tissue transglutaminase with total IgA while the child is still on gluten; confirm with biopsy when appropriate.
- For dehydration, use oral rehydration solution when tolerated; give IV isotonic fluid for shock or failed oral therapy.
- Neonatal jaundice needs measurement and age-specific interpretation, not visual estimation.
Worked example
A 4-week-old boy has projectile vomiting after feeds but is hungry and alert. Biochemistry shows hypochloraemia, hypokalaemia and metabolic alkalosis. This is pyloric stenosis. Give IV 0.9% saline with potassium replacement, confirm by ultrasound and arrange pyloromyotomy after correcting fluids and electrolytes. Do not feed orally until the diagnosis is managed.
Traps
Missing bilious vomiting as a surgical emergency; treating pyloric stenosis before correcting alkalosis; overdiagnosing reflux; ordering celiac serology after gluten exclusion; underestimating dehydration in a lethargic child.