Synopsis
Translate obstructive and penetrating Crohn symptoms into defined anatomy, control abscess and sepsis before immune escalation, distinguish inflammatory from fixed stenosis, and select drainage, endoscopic dilatation, strictureplasty or resection while preserving bowel length.
- Use CT in an acute obstructive or septic presentation; use MRE or intestinal ultrasound for planned small-bowel mapping and reduced cumulative radiation.
- Describe each stricture by site, length, upstream dilatation, inflammatory features, accessibility, angulation, penetrating disease and cancer concern rather than calling it simply active Crohn.
- Drain an accessible Crohn abscess radiologically where possible and, if the patient improves, avoid definitive surgery for at least two weeks while nutrition and medicines are optimised.
Key red flags
Colicky pain becoming constant with guarding, rebound, fever or lactate rise suggests strangulation, perforation or abscess and requires immediate surgical reassessment.
Bilious vomiting, marked distension, absolute constipation and worsening renal function indicate high-grade obstruction and dangerous fluid sequestration.
A tender abdominal or perianal mass with rigors and immunosuppression suggests a collection that needs imaging and drainage rather than a higher immunosuppressive dose.
High-output enterocutaneous fistula with dehydration, electrolyte loss, skin injury or falling weight requires fluid, nutrition and sepsis control before reconstruction.
Investigation priorities
define an acute transition point, bowel compromise, abscess, fistula, perforation and another surgical cause.
Management branches
A 28-year-old weighing 72 kg with terminal ileal Crohn disease has fever 38.5°C, pulse 112/min, right iliac fossa tenderness, CRP 198 mg/L and 8 kg weight loss. CT shows a 6 cm ileal stricture, proximal dilatation and a separate safely accessible 4 cm abscess, without free perforation.
- Treat intra-abdominal sepsis with intravenous fluid and blood cultures. Confirm no penicillin hypersensitivity, no previous severe immediate reaction to another beta-lactam, no previous co-amoxiclav-associated jaundice/hepatic injury and creatinine clearance above 30 mL/min. Start co-amoxiclav 1 g/200 mg IV every 8 hours over 30–40 minutes, review at 48 hours against cultures and local resistance data, withhold the next biologic dose and involve interventional radiology, gastroenterology and colorectal surgery.
- Drain the 4 cm collection percutaneously, sending 45 mL of pus for culture; adjust antibiotics to the isolated E coli and monitor drain output, observations, renal function and CRP.