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Intussusception
Intussusception is the most common cause of bowel obstruction in toddlers; ultrasound makes the diagnosis (a "target"), and an air or liquid enema under imaging guidance reduces it in most cases — surgery only for failure, perforation or peritonitis.
Why it matters in the exam
The classic case is a toddler aged six months to three years with bouts of colicky abdominal pain — crying, drawing the legs up to the abdomen and then settling — vomiting, and later lethargy and apathy between bouts. Sometimes a sausage-shaped mass is felt in the right upper quadrant, and "redcurrant jelly" stool (blood and mucus) is a late sign. Most cases are ileocolic and have no "lead point"; the exam checks that you recognise the picture even without the classic triad, which appears in only a minority of children.
The second part is treatment: after fluid resuscitation, and in the absence of perforation, shock or peritonitis — an air (pneumatic) or liquid enema under fluoroscopic or ultrasound guidance, which succeeds in most cases. With failure, perforation or peritonitis — surgery, sometimes with bowel resection. Intussusception recurs in about one child in ten. In an older child (above age 3–5) or an adult, a "lead point" is sought — Meckel's, a polyp, lymphoma or HSP — and in adults it is usually a tumour, so treatment is resection rather than an enema.
Key points
- Toddler aged six months to 3, colicky pain, legs drawn up, lethargy between bouts.
- Ultrasound — "target"; "redcurrant jelly" stool is late.
- Air or liquid enema under imaging guidance — succeeds in most cases.
- Surgery: perforation, peritonitis, shock or failed enema.
- Older child or adult — lead point; in adults usually a tumour.
Summary table
| Topic | Finding | Exam note |
|---|---|---|
| Who | Aged six months to 3 years; usually ileocolic without a lead point | Older child or adult — look for a lead point |
| Clinical picture | Colicky pain with legs drawn up, vomiting, lethargy between bouts, "sausage" mass | "Redcurrant jelly" stool — a late sign |
| Diagnosis | Ultrasound: "target" or "doughnut" sign | The test of choice |
| Treatment | Air or liquid enema under imaging guidance | Succeeds in most cases; recurrence in about one in ten |
| Indication for surgery | Perforation, peritonitis, shock or failed enema | Sometimes bowel resection |
| Adult | Lead point, usually a tumour | Resection, not an enema |
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Sources
- Holcomb and Ashcraft's Pediatric Surgery, 7th edition (2020) — Intussusception
- Sabiston Textbook of Surgery, 21st edition (2022) — Pediatric Surgery
- ESPR/ESPU guidance on imaging and enema reduction of intussusception in children, 2017 — Ultrasound diagnosis and image-guided reduction
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.