Inflammatory bowel disease flares
Acute severe ulcerative colitis needs IV steroids, clot prevention and the surgeons involved from day one. Exclude infection, including amoebic colitis and TB.
A 28-year-old man with ulcerative colitis diagnosed 2 years ago stopped his mesalazine 3 months ago because of cost. For a week he has had 9 bloody stools a day, cramping and urgency. Pulse 104, temperature 37.9 °C, BP 112/70. Hb 10.2 g/dL, CRP 70 mg/L, albumin 2.9 g/dL, potassium 3.1 mmol/L. Abdomen tender but soft. Stool cultures not yet sent.
Is this acute severe colitis, what do you start today, and what do you decide on day 3?
- Truelove and Witts6 or more bloody stools a day plus one systemic feature is acute severe colitis.
- Admit and start IV steroidsHydrocortisone or methylprednisolone.
- Exclude infectionStool culture, C. difficile, amoebae (common in Pakistan). CMV on biopsy if not responding.
- Abdominal X-rayTransverse colon over 5.5 cm is toxic megacolon.
- Fluids, potassium, magnesiumLow potassium raises megacolon risk.
- EnoxaparinClot prevention even with rectal bleeding.
- Stop the dangerous drugsOpioids, loperamide, hyoscine, NSAIDs.
- Day-3 reviewNot responding: rescue therapy or colectomy. Gastroenterology and surgery together.
- Toxic megacolon
- Perforation or peritonism
- Massive bleeding
- Not improving by day 3
- Crohn's with fever and a tender mass (abscess)
- Fewer stools but a distended, quiet abdomen
- Toxic megacolon
- Perforation hidden by steroids
- Amoebic colitis
- C. difficile or CMV colitis
- Intestinal TB mimicking Crohn's
- Venous thromboembolism
| Acute severe UC | 6 or more bloody stools a day plus pulse above 90, temperature above 37.8 °C, Hb below 10.5 g/dL, or ESR above 30 (CRP above 30) |
| Hydrocortisone | 100 mg IV 6-hourly (or methylprednisolone 60 mg IV daily) |
| Enoxaparin | 40 mg subcutaneously daily, even with bloody diarrhoea |
| Toxic megacolon | Transverse colon above 5.5 cm with systemic toxicity |
| Day 3 | More than 8 stools, or 3–8 with CRP above 45, predicts steroid failure |
| Potassium target | Above 4.0 mmol/L |
Check every dose against a current drug reference and your hospital protocol.
On this page
UC and Crohn's in brief
| Feature | Ulcerative colitis | Crohn's disease |
|---|---|---|
| Site | Rectum upwards, continuous | Anywhere mouth to anus, skip lesions, often terminal ileum |
| Depth | Mucosal | Transmural |
| Main symptoms | Bloody diarrhoea, urgency | Pain, diarrhoea, weight loss, perianal disease |
| Complications | Toxic megacolon, cancer | Strictures, fistulas, abscesses, malabsorption |
| Smoking | Seems protective | Makes it worse |
| Histology | Crypt abscesses, no granulomas | Granulomas, transmural inflammation |
IBD is increasingly diagnosed in Pakistan, but infections that mimic IBD are common: amoebic colitis, intestinal TB, bacterial dysentery and C. difficile. Exclude them before or alongside steroids, and before biologics.
History
- Stool frequency (day and night), blood, urgency, incontinence, pain.
- How long? Previous flares and what worked? Current medicines and adherence (cost is a common reason for stopping).
- Recent antibiotics, hospital stay, travel, sick contacts.
- Weight loss, night sweats, TB contacts or past TB.
- Extra-intestinal features: mouth ulcers, joint pain, red eyes, skin lesions (erythema nodosum, pyoderma).
- Crohn's: perianal pain or discharge, abdominal mass, obstructive symptoms.
Examination
- Pulse, temperature, BP, hydration, weight.
- Abdominal tenderness, distension, bowel sounds, peritonism.
- Perianal examination (Crohn's).
- Mouth, joints, eyes, skin.
How severe? Truelove and Witts
Outpatient: mesalazine oral and rectal
Oral prednisolone 40 mg plus mesalazine
- Admit
- IV steroids
- joint gastro and surgical care
Differential diagnosis
| Condition | Points towards it | Test |
|---|---|---|
| Amoebic colitis | Blood and mucus, less fever, flask-shaped ulcers, liver abscess | Stool microscopy, serology, biopsy |
| Bacterial dysentery | Acute, high fever, contacts | Stool culture |
| C. difficile | Recent antibiotics or hospital stay | Stool toxin or PCR |
| Intestinal TB | Ileocaecal disease, weight loss, chest TB, ascites | Biopsy, histology, GeneXpert, chest X-ray |
| CMV colitis | Steroid-refractory, immunosuppressed | Biopsy |
| Ischaemic colitis | Older, vascular disease, sudden | CT |
| Colon cancer | Older, weight loss, change in bowel habit | Colonoscopy |
Starting high-dose steroids for undiagnosed amoebic colitis or TB can be disastrous. Send stool tests before the first dose, and biopsy early.
Investigations
| Test | Why |
|---|---|
| CBC, CRP, ESR | Severity, response |
| Urea, electrolytes, magnesium | Dehydration, low potassium and magnesium |
| Albumin, LFTs | Severity, nutrition, liver disease (PSC) |
| Stool culture, C. difficile, ova and parasites | Infection |
| Abdominal X-ray (daily if severe) | Toxic megacolon, mucosal islands |
| Flexible sigmoidoscopy with biopsies | Confirm, exclude CMV and amoebiasis |
| CT abdomen | Perforation, abscess, Crohn's complications |
| Hepatitis B, HIV, TB screening (IGRA, chest X-ray) | Before biologics or immunosuppressants |
| TPMT if available | Before azathioprine |
Management of acute severe UC
- Admit, IV steroidsHydrocortisone 100 mg IV 6-hourly or methylprednisolone 60 mg daily.
- SupportiveIV fluids, potassium and magnesium, nutrition, enoxaparin.
- AvoidOpioids, loperamide, codeine, hyoscine, NSAIDs.
- DailyStool chart, observations, abdominal examination, CRP, X-ray if distended.
- Day 3More than 8 stools, or 3–8 with CRP above 45: rescue therapy (infliximab or ciclosporin) or colectomy.
- ImprovingSwitch to oral prednisolone 40 mg with a reducing course, plus maintenance.
Toxic megacolon and perforation
- Colon wider than 5.5 cm with fever, fast pulse, low BP, confusion.
- Triggers: low potassium, opioids, anti-diarrhoeals, delayed steroids, colonoscopy.
- Steroids hide peritonitis. A patient on high-dose steroids can perforate with few signs. Fewer stools with a distended, quiet abdomen is a bad sign, not a good one.
- Surgeon now. Colectomy is often needed.
Crohn's flare
- Moderate to severe: steroids (oral or IV), nutrition, and treatment of complications.
- Abscess (fever, tender mass): antibiotics and drainage before steroids.
- Obstruction from strictures: drip and suck, surgical review.
- Perianal fistula or abscess: surgical drainage, MRI.
- Exclude intestinal TB before immunosuppression, especially with ileocaecal disease.
Treatment doses
Common mistakes
- Starting steroids without sending stool tests.
- Giving codeine or loperamide for diarrhoea in a colitis flare.
- Holding enoxaparin because of rectal bleeding.
- Missing toxic megacolon because the stool count went down.
- Continuing IV steroids beyond day 5–7 without a rescue plan.
- Treating intestinal TB as Crohn's.
- Letting a patient stop maintenance therapy without a cheaper alternative.
Follow-up
- Switch to oral prednisolone with a reducing course once improving.
- Maintenance: mesalazine, azathioprine or biologics under gastroenterology. Discuss costs openly in Pakistan and choose something the patient can keep taking.
- Bone protection (calcium and vitamin D) on steroids.
- Colonoscopy surveillance for cancer in long-standing colitis.
Frequently asked questions
What are the Truelove and Witts criteria?
Six or more bloody stools a day plus at least one of pulse above 90, temperature above 37.8 °C, Hb below 10.5 g/dL, or ESR above 30. This defines acute severe ulcerative colitis.
Why is enoxaparin given despite rectal bleeding?
IBD flares carry a high risk of DVT and PE, and prophylactic doses are safe in colitis.
Which infections mimic IBD in Pakistan?
Amoebic colitis, intestinal TB, bacterial dysentery and C. difficile.
What happens if steroids don't work by day 3?
More than 8 stools a day, or 3–8 with CRP above 45, predicts failure. Rescue therapy with infliximab or ciclosporin, or colectomy, is discussed with gastroenterology and surgery.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A patient with UC has 9 bloody stools a day, pulse 104 and CRP 70. What is the classification?
Answer: Acute severe colitis. Truelove and Witts: 6 or more bloody stools plus a systemic feature.
- Moderate colitis: Systemic features make it severe.
- Irritable bowel: No.
- Infective diarrhoea only: Exclude infection, but this is a UC flare.
- Mild colitis: Too many stools and systemic features.
2. What is the first-line treatment of acute severe ulcerative colitis?
Answer: IV hydrocortisone. IV steroids with VTE prophylaxis, and review at day 3.
- Morphine: Risk of megacolon.
- Loperamide: Dangerous.
- Antibiotics only: No.
- Oral mesalazine alone: Not enough.
3. In Pakistan, which condition must be excluded before treating suspected Crohn's disease with strong immunosuppression?
Answer: Intestinal TB. Ileocaecal TB mimics Crohn's; immunosuppression can make it worse.
- Coeliac disease: Less relevant.
- Gastric ulcer: No.
- Hepatitis A: No.
- Gallstones: No.
4. Which feature favours Crohn’s disease over ulcerative colitis?
Answer: Perianal fistulae and skip lesions. Crohn’s: any part of the GI tract (terminal ileum commonest), skip lesions, transmural inflammation, non-caseating granulomas, cobblestone mucosa, fistulae, strictures, perianal disease; smoking worsens it. UC: rectum upwards in continuity, mucosal only, crypt abscesses, pseudopolyps, PSC association, smoking protective. Both carry colorectal cancer risk with long colonic disease.
- Continuous disease from rectum: Continuous disease from the rectum is typical of UC.
- Crypt abscesses only: Crypt abscesses occur in both and do not distinguish them.
- Primary sclerosing cholangitis: PSC is more common with UC.
5. A man with long-standing Crohn disease has recurrent small bowel obstruction from multiple short fibrotic ileal strictures; previous resections have been performed. What procedure preserves bowel length?
Answer: Strictureplasty. Crohn surgery principles: surgery is not curative — conserve bowel. Indications: fibrotic stricture with obstruction, fistula, abscess, perforation, bleeding, failed medical therapy, cancer. Strictureplasty (Heineke–Mikulicz for short, Finney for longer strictures) relieves obstruction without resection; limited resection with primary anastomosis for ileocaecal disease. Avoid repeated resections → short bowel syndrome. Stop smoking (reduces recurrence).
- Extensive small bowel resection: Extensive resection risks short bowel syndrome.
- Total colectomy: This is small bowel disease, not colonic.
- Ileostomy alone: An ileostomy does not relieve strictures.
6. After 2 days of obstructed labour, a woman leaks urine constantly from the vagina a week after delivery. What is the most likely cause?
Answer: Vesicovaginal fistula. In prolonged obstructed labour, the fetal head presses the bladder base against the pubis, causing ischaemic necrosis. The dead tissue sloughs after several days, leaving a vesicovaginal fistula with continuous leakage. Prevention is timely delivery; repair is surgical.
- Stress incontinence: Leakage with coughing, not continuous.
- Urge incontinence: Sudden urge; not continuous.
- Overflow incontinence: Possible after delivery but leakage is with a full bladder.
- Ureteric colic: Pain, not leakage.
7. After resection of the terminal ileum for Crohn's disease, which problems are expected?
Answer: Bile acid diarrhoea, low B12. The terminal ileum absorbs vitamin B12 (with intrinsic factor) and reabsorbs bile acids (enterohepatic circulation). Loss causes B12 deficiency, bile acid diarrhoea (bile acids irritate the colon), fat malabsorption, and gallstones (cholesterol-supersaturated bile). Increased oxalate absorption can also cause kidney stones.
- Iron deficiency alone: Iron is absorbed in the duodenum.
- Folate excess: Folate absorption is in the jejunum and not excessive.
- Lactose intolerance alone: Not the main issue.
- Hypercalcaemia: Calcium tends to fall with fat malabsorption.
References and dose sources
- NICE NG129 — Crohn's disease
- NICE NG130 — ulcerative colitis
- BSG — IBD guideline (2019)
- Hydrocortisone dosing: Drugs.com: Hydrocortisone dosage (see also our hydrocortisone dose page)
- Prednisolone dosing: Drugs.com: Prednisolone dosage (see also our prednisolone dose page)
- Enoxaparin dosing: Drugs.com: Enoxaparin dosage (see also our enoxaparin dose page)
- Potassium chloride dosing: Drugs.com: Potassium chloride dosage (see also our potassium chloride dose page)
- Metronidazole dosing: Drugs.com: Metronidazole dosage (see also our metronidazole dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.