Gastroenterology
Vomiting, constipation and the acute abdomen in children.
Use as a study guide only. These notes are part of a free open-access medical education (FOAMed) project and may contain errors or outdated information. Always verify against current guidelines (e.g. eTG, RACGP, local health district policies) and reputable sources before applying anything to patient care. See the full disclaimer.
Clinical pearls & learnings
Tips and tricks collected over the years — a living list that grows with every rotation. Use as a study guide only and check current guidelines before acting on anything.
Abdominal emergencies
Vomiting and constipation — congenital causes to remember
Congenital causes — the presenting clue and why it matters
| Condition | Presenting clue | Why it matters |
|---|---|---|
| Meckel's diverticulum | Painless rectal bleeding; may present as intussusception, volvulus or obstruction | The most common congenital GI anomaly |
| Hirschsprung disease | Delayed passage of meconium (>48h), chronic constipation, abdominal distension in an infant | Aganglionic segment of colon — needs biopsy and surgical management |
| Biliary atresia | Prolonged neonatal jaundice with pale stools and dark urine (conjugated hyperbilirubinaemia) | Time-critical — outcomes depend on early Kasai portoenterostomy |
Always actively consider torsion (testicular or ovarian) in a child with abdominal pain — it's easily missed when the pain is diffuse or the history is vague, and time to detorsion determines organ salvage.
Rat lungworm disease — a slug/snail exposure
Angiostrongylus cantonensis infection from ingesting an infected slug or snail (including accidentally, e.g. on unwashed produce, or a child eating one directly) can cause eosinophilic meningitis. Management is supportive, with early infectious diseases input — there's no single definitive antiparasitic protocol, and treatment decisions (including whether to use anthelmintics, which can theoretically worsen inflammation as larvae die) are best made with specialist guidance.
Intussusception (ISS)
Peak incidence 6–18 months, typically secondary to inflamed Peyer's patches following a viral gastroenteritis (the hypertrophied lymphoid tissue acts as a lead point).
- Classic triad: colicky abdominal pain, vomiting, and redcurrant-jelly (bloody, mucoid) stools — but the full triad is often absent, so keep it on the differential with any two of these.