Ileal pouch surgery and pouchitis

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

Restorative proctocolectomy removes the colon and rectum and constructs an ileal reservoir, usually a J pouch, connected to the anal canal. The operation can be performed in stages. A prior subtotal colectomy may allow recovery from acute severe colitis, malnutrition and high-dose corticosteroids before pelvic dissection. A covering loop ileostomy may reduce the clinical consequence of a pouch anastomotic leak but creates its own dehydration, obstruction and closure risks. The choice is therefore individual and should be made with an experienced pouch team.

Expected pouch function is not identical to pre-disease bowel function. Patients need realistic discussion of daytime and night-time frequency, urgency, seepage, dietary adaptation, antidiarrhoeal strategies, fertility and sexual or urinary consequences. A permanent end ileostomy is a valid comparator. The surgeon should also review sphincter function, Crohn phenotype, prior pelvic radiotherapy, dysplasia or cancer anatomy and comorbidity because these influence whether a pouch is feasible and whether mucosectomy, cuff length or staging changes risk.

Pouchitis is an inflammatory syndrome of the ileal reservoir supported by symptoms, endoscopic inflammation and histology. Increased frequency, urgency, cramps, nocturnal seepage and malaise are typical, but the symptom pattern is not specific. Cuffitis affects retained rectal mucosa; pre-pouch ileitis or fistulation raises Crohn-like disease; an anastomotic stricture causes difficult evacuation; and an occult pelvic collection may cause pain, fever or failure to thrive. BSG therefore recommends structured assessment rather than diagnosing from symptoms alone.

For a confirmed acute episode, BSG recommends two weeks of ciprofloxacin or metronidazole. The 2001 randomised trial used ciprofloxacin 1000 mg/day or metronidazole 20 mg/kg/day for 14 days, and ciprofloxacin was better tolerated in that small study. UK prescribing must also follow the 2024 MHRA restriction: fluoroquinolones are reserved for situations in which other commonly recommended antibiotics are inappropriate because disabling and potentially irreversible adverse effects can occur. Recurrent or antibiotic-refractory inflammation requires pouch-expert review and a phenotype-specific plan rather than indefinite unexamined antibiotic exposure.

Key points

An ileal pouch–anal anastomosis uses ileum as a reservoir after the colon and rectum are removed; it avoids a permanent stoma but does not restore normal colonic storage.
Pouch choice belongs in a high-volume specialist discussion covering stool frequency, urgency, seepage, fertility, sexual and urinary function, pouch failure and the alternative of a permanent ileostomy.
Fever, tachycardia, escalating pelvic or abdominal pain, ileus or purulent drain output soon after pouch surgery suggests anastomotic leak or pelvic sepsis and needs urgent CT-led source-control assessment.
New frequency and urgency alone do not prove pouchitis: check stool culture and Clostridioides difficile, examine the pouch, pre-pouch ileum and anal transition zone, and use pelvic MRI when structural sepsis or fistula is possible.
BSG recommends a 2-week course of ciprofloxacin or metronidazole for acute pouchitis, but current MHRA restrictions mean a systemic fluoroquinolone is used only when other commonly recommended antibiotics are inappropriate.
Symptoms returning soon after antibiotics suggest chronic antibiotic-dependent pouchitis; non-response should prompt reassessment for cuffitis, Crohn-like disease, stricture, ischaemia, infection or a leak rather than serial blind prescriptions.
Pouch inflammation, the retained rectal cuff and pre-pouch ileum are different anatomical targets and their distribution changes treatment.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Microbial and immune dysregulation

Exposure of ileal mucosa to prolonged faecal stasis changes the microbial environment and mucosal immune response, contributing to idiopathic pouch inflammation.

Secondary infectious inflammation

Clostridioides difficile and other enteric pathogens can produce an acute pouch syndrome and must be sought before labelling it idiopathic pouchitis.

Mechanical or septic drivers

Anastomotic leak, chronic sinus, stricture, pouch twist or incomplete emptying can cause stasis, pain and secondary inflammation.

Underlying Crohn phenotype

Pre-pouch ileitis, deep ulceration, non-anastomotic stenosis or later fistulation may reveal Crohn-like disease in a person whose original colectomy diagnosis was ulcerative or indeterminate colitis.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Loss of colonic reservoir
The ileal pouch supplies storage after proctocolectomy but has lower capacity and different absorption than colon, so increased frequency and water loss are expected even when healthy.
2
Pouch mucosal inflammation
Neutrophilic mucosal injury causes erythema, friability and ulceration, reducing reservoir compliance and producing urgency, frequency, cramps and seepage.
3
Pelvic sepsis and fibrosis
An anastomotic leak seeds a presacral collection; persistent inflammation can form a sinus or fistula and scar the pelvis, compromising function and later closure.
4
Cuff inflammation
A short retained rectal mucosal cuff can remain susceptible to ulcerative inflammation, producing bleeding and tenesmus despite a relatively normal ileal pouch.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Acute pouchitis pattern

Frequency, urgency, cramping, nocturnal leakage, malaise and sometimes low-grade fever developing over days support acute pouch inflammation, but need endoscopic and microbiological correlation.

Early pelvic sepsis pattern

In the first postoperative days or weeks, tachycardia, fever, escalating pelvic pain, ileus, purulent drainage or organ dysfunction should be treated as a possible pouch-anastomotic leak or infected collection.

Cuff-localised symptoms

Tenesmus, bleeding and anal discomfort with an otherwise normal pouch suggest inflammation in retained rectal cuff mucosa; the cuff must be viewed and biopsied rather than assumed to share pouch pathology.

Crohn-like pouch disease

Pre-pouch ileitis, a non-anastomotic stricture, deep ulceration or a new fistula after the expected postoperative period raises a Crohn phenotype and changes long-term medical and surgical choices.

Mechanical evacuation problem

Straining, incomplete emptying, clustering and obstructive pain may reflect anastomotic stenosis, pouch twist, prolapse or pelvic-floor dysfunction; antibiotics do not correct these causes.

Red flags requiring action

After pouch construction, a rising pulse with fever, pelvic pain, ileus or abnormal drain fluid is a leak pattern until imaging and surgical assessment show otherwise; shock or organ dysfunction demands immediate source control.
High pouch output with oliguria, postural symptoms or rising creatinine indicates clinically important dehydration and requires same-day assessment.
A new fistula, deep ulcer, pre-pouch ileitis, obstructive pattern or failure of a correctly delivered acute course requires specialist re-phenotyping.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
Stool culture and Clostridioides difficile assayFirst step
Why
Exclude enteric infection before attributing increased pouch output to idiopathic inflammation.
Interpretation and limitations
A detected pathogen redirects treatment and infection control; a negative result does not itself prove pouchitis.
02
Pouchoscopy with segmental biopsies
Why
Inspect the pouch body, afferent pre-pouch ileum and anal transition zone or cuff and obtain histology from the affected and comparison areas.
Interpretation and limitations
Diffuse pouch-body erythema, friability and ulceration with compatible histology supports pouchitis; cuff-only disease, pre-pouch ileitis or focal deep ulcers indicates another phenotype.
03
Pelvic MRI
Why
Assess pelvic sepsis, sinus, fistula and structural complications in ongoing or atypical symptoms after pouch surgery.
Interpretation and limitations
A collection or tract requires colorectal source-control planning; a normal MRI does not exclude mucosal pouchitis, which needs pouchoscopy.
04
Contrast CT abdomen and pelvis in acute postoperative deterioration
Why
Rapidly identify leak, abscess, ileus, obstruction or free perforation when the patient is acutely unwell.
Interpretation and limitations
Extraluminal gas or contrast and a rim-enhancing collection near the anastomosis require urgent surgical and radiological review rather than outpatient pouchitis treatment.
05
Full blood count, CRP, renal profile, magnesium and albumin
Why
Measure inflammation, anaemia, dehydration, electrolyte loss and nutritional consequence.
Interpretation and limitations
AKI or marked inflammatory response increases urgency and affects antimicrobial and fluid choices; normal bloods do not exclude localised pouch inflammation.
06
Examination including digital rectal examination when safe
Why
Assess hydration, peritonism, perianal disease, anastomotic narrowing, tenderness and retained stool.
Interpretation and limitations
Peritonism or severe systemic illness overrides routine endoscopy; a tight anastomosis or evacuation disorder directs mechanical assessment.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Cuffitis

Bleeding, tenesmus and inflammation restricted to retained rectal mucosa on direct segmental examination distinguish cuffitis from diffuse pouch-body disease.

Crohn-like disease of the pouch

Pre-pouch ileitis, deep ulcers, fistula or a non-anastomotic stricture suggests transmural Crohn biology and often requires advanced therapy or surgery.

Clostridioides difficile or enteric infection

Acute watery output after antibiotics, healthcare exposure or sick contacts requires stool testing because treatment and infection control differ.

Anastomotic stricture or evacuation disorder

Difficult emptying, straining and clustering with a narrowed outlet or abnormal pelvic-floor mechanics will not resolve with antibiotics.

Pelvic collection or chronic sinus

Pain, fever, discharge, failure to thrive or persistent inflammation after surgery needs cross-sectional pelvic imaging and source-control review.

Additional chapter-specific clues

Expected function versus inflammatory change

Establish the patient’s own stable pouch baseline. A rise from five formed or porridge-like stools to twelve watery stools with new urgency and nocturnal seepage is more meaningful than applying a single universal frequency threshold.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01Worked case: a first confirmed acute pouchitis episodeConfirm distribution and infection status before a finite antibiotic courseFirst stepA 39-year-old weighing 60 kg is three years after ileal pouch–anal anastomosis for ulcerative colitis. Their stable baseline is five stools by day and none at night; over six days this rises to twelve watery stools, two nocturnal episodes, urgency and cramps. Temperature is 37.2°C, pulse 84/min and there is no guarding.

1Assess hydration, abdominal and perianal findings and medication exposure. Full blood count and creatinine are normal, CRP is 19 mg/L, and there is no postoperative sepsis pattern requiring emergency CT.
2Send stool culture and Clostridioides difficile testing; both are negative. Arrange pouchoscopy because symptoms alone cannot distinguish pouchitis from cuffitis, pre-pouch ileitis or mechanical disease.
3Pouchoscopy shows diffuse pouch-body erythema, friability and shallow ulcers. The pre-pouch ileum and 1.5 cm rectal cuff look normal; biopsies show active pouch mucosal inflammation without cytomegalovirus inclusions.
4After specialist and antimicrobial review, prescribe metronidazole 400 mg orally three times daily with or after food for 14 days: 1200 mg/day is exactly 20 mg/kg/day for this 60 kg patient. Explain that the trial verified total daily dose, not division frequency; this tablet schedule implements it with the current 400 mg product. Counsel about alcohol avoidance for 48 hours after the last tablet and arrange leucocyte and neurological review because treatment exceeds 10 days.
5At day 14 the patient reports six daytime stools, no nocturnal stools or urgency, CRP is 4 mg/L and treatment stops. Document the new baseline; recurrence, bleeding, fever or non-response triggers repeat phenotype assessment rather than an automatic repeat prescription.

02Early postoperative leak and pelvic collectionTreat pelvic sepsis as a source-control emergencyOn day 8 after pouch construction with a defunctioning loop ileostomy, a 31-year-old develops pulse 126/min, temperature 39.0°C, lower abdominal pain, ileus and purulent pelvic-drain output.

1Start ABCDE assessment, obtain large-bore intravenous access, blood tests including lactate and renal function, blood and drain cultures, intravenous fluid resuscitation and locally approved broad-spectrum intravenous antibiotics.
2Call the pouch surgeon and anaesthetist immediately. Contrast CT shows a 7 cm presacral collection and extraluminal contrast at the pouch anastomosis; this is not uncomplicated pouchitis.
3The colorectal and interventional-radiology teams place a CT-guided drain because the patient responds to resuscitation and the collection is accessible. The covering ileostomy remains in place and drain fluid is cultured to narrow antibiotics.
4By 48 hours pulse is 88/min, lactate has fallen from 3.1 to 1.2 mmol/L and drain output is decreasing. Repeat imaging at day 6 shows the cavity reduced to 2.4 cm.
5Delay ileostomy closure. Six weeks later MRI and examination under anaesthesia show a closed sinus and no residual collection; the specialist MDT records whether later closure is safe and discusses long-term pouch-function risk.

03Symptoms recur after each antibiotic courseRe-phenotype chronic or antibiotic-dependent diseaseA 46-year-old has four endoscopically confirmed episodes in nine months. Symptoms settle during antibiotics but recur within two weeks of stopping, and the latest course gives only partial benefit.

1Review every prior culture, antibiotic, adverse effect and response, and repeat stool culture and Clostridioides difficile testing rather than assuming identical disease.
2Repeat pouchoscopy with pouch, cuff and pre-pouch biopsies and obtain pelvic MRI. Findings show chronic pouch-body inflammation, normal cuff, no stricture, no fistula and no collection.
3Classify chronic antibiotic-dependent pouchitis and, after infection screening, start vedolizumab 300 mg IV over 30 minutes at weeks 0, 2 and 6 then every 8 weeks. The specialist also gives a four-week standard-of-care antibiotic alongside induction; in this patient ciprofloxacin is inappropriate after prior tendon pain, so metronidazole 400 mg orally three times daily is selected with leucocyte and neurological monitoring beyond day 10.
4Set measurable outcomes: daytime and nocturnal frequency, urgency, bleeding, weight, haemoglobin, CRP and repeat endoscopic activity. A new fistula, stenosis or pre-pouch ileitis prompts reassessment for Crohn-like disease.
5EscalationAt week 14 after vedolizumab escalation, frequency has fallen from fourteen to seven daily, weight has risen 2 kg and pouchoscopy shows healed ulcers. Continue only after documenting objective benefit; absence of benefit by week 14 would trigger discontinuation consideration and medical-surgical pouch-failure review.

Key medicines and prescribing safety3 treatments · regimens, roles and cautions

One BSG-listed two-week acute-pouchitis antibiotic, selected here after microbiological and anatomical confirmation.

Metronidazole 400 mg tablets for confirmed acute pouchitis

For the 60 kg worked patient, give 400 mg orally three times daily with or after food for 14 days: 1200 mg/day equals the trial’s 20 mg/kg/day. This division uses the active 400 mg tablet; the trial abstract verified total daily dose and duration, not exact frequency, and pouchitis use is specialist-selected rather than a licensed product indication.

Avoid in nitroimidazole hypersensitivity. Do not drink alcohol during treatment or for 48 hours afterwards. Because the course exceeds 10 days, arrange clinical and laboratory review including leucocyte count and monitor paraesthesia, ataxia, dizziness or seizures. Review severe hepatic disease, warfarin/INR, lithium, disulfiram and ciclosporin interactions.

A BSG-listed two-week alternative whose selection is restricted by current MHRA fluoroquinolone safety advice.

Ciprofloxacin 500 mg tablets for acute pouchitis when other antibiotics are inappropriate

When a specialist documents that other commonly recommended antibiotics are inappropriate, give 500 mg orally twice daily for 14 days. With CrCl 30–60 mL/min the selected product permits 250–500 mg every 12 hours; at 30 mL/min or below use 250–500 mg every 24 hours, including after haemodialysis.

Do not combine with tizanidine and avoid concurrent corticosteroids because tendon rupture risk increases. Stop at tendon pain, neuropathy, muscle weakness or neuropsychiatric effects. Give oral ciprofloxacin 1–2 hours before or at least 4 hours after iron, calcium, magnesium, aluminium, sucralfate or phosphate binders; do not take it with dairy or mineral-fortified drink alone, and review QT, warfarin and theophylline risks.

Provides a licensed advanced anti-inflammatory option for objectively confirmed chronic pouchitis after antibiotic failure.

Entyvio vedolizumab for chronic pouchitis after antibiotic failure

For an adult with moderately-to-severely active chronic pouchitis after inadequate or lost antibiotic response, give 300 mg by IV infusion over 30 minutes at weeks 0, 2 and 6, then every 8 weeks. Start in parallel with a specialist-selected four-week standard-of-care antibiotic and consider discontinuation if there is no benefit by week 14.

Do not start with active severe infection. Observe continuously during every infusion, for about 2 hours after each of the first two infusions and about 1 hour after later infusions, with anaphylaxis treatment available. Stop a severe infusion reaction, record product name/batch, and note that no renal or hepatic dose recommendation is available because these groups were not studied.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Dehydration and acute kidney injury

High liquid output and reduced colonic water absorption can cause thirst, oliguria, sodium or magnesium loss and rising creatinine.

Chronic antibiotic-dependent pouchitis

Symptoms recur soon after stopping antibiotics, creating repeated exposure and a need for phenotype-directed maintenance planning.

Chronic antibiotic-refractory pouchitis

Persistent clinical and endoscopic inflammation despite adequate antibiotic treatment requires exclusion of secondary causes and advanced medical-surgical review.

Pouch fistula, sinus or stricture

Sepsis and fibrosis can create tracts or narrowing that impair evacuation and may require drainage, dilation, revision or diversion.

Pouch failure

Uncontrolled inflammation, sepsis, poor function or Crohn-like complications may ultimately require permanent diversion or pouch excision after specialist review.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

Record an individual pouch baseline: daytime and nocturnal stool frequency, urgency, seepage, pain, bleeding, diet, antidiarrhoeal use and quality-of-life goals.
For an acute episode, check response during and at completion of the 14-day course. If metronidazole exceeds 10 days, include clinical and leucocyte monitoring; persistent fever, pain, dehydration, neurological symptoms or worsening output needs earlier reassessment.
Track renal function and electrolytes when output is high and full blood count, CRP, albumin, iron and weight in recurrent or chronic inflammation.
For repeated episodes, document cumulative antibiotic exposure, cultures, resistance and adverse effects. Avoid corticosteroids with ciprofloxacin, record renal interval and cation spacing, and monitor metronidazole neurological toxicity and leucocyte count when use exceeds 10 days.
Use repeat pouchoscopy and pelvic imaging when objective confirmation will change escalation, and maintain separate surveillance of pouch, cuff or retained rectum according to dysplasia history and current IBD surveillance guidance.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

An anatomical diagnosis prevents wrong treatment

Pouch body, pre-pouch ileum, rectal cuff and anastomosis can each produce urgency or bleeding but require different treatment.

The stoma may protect consequences, not prevent a leak

A covering loop ileostomy can reduce faecal load across a new pouch anastomosis yet a leak and pelvic collection can still occur.

Pouch choice includes a permanent-ileostomy comparison

Informed consent should compare real function, reoperation and failure risks rather than presenting restoration of continuity as the only successful outcome.

Antibiotic response is not a final diagnosis

Short improvement can occur despite an occult structural or inflammatory driver; recurrence should prompt localisation and reclassification.

High-volume experience matters

BSG advises that pouch discussions and surgery occur with an experienced team in a high-volume centre because selection, technique and rescue of complications are specialised.

11Common pitfallsFrequent interpretation and management errors.

01
Calling every rise in frequency pouchitis misses infection, cuffitis, Crohn-like disease, stricture and pelvic sepsis.
02
Giving repeated antibiotics without pouchoscopy, stool testing or a stop-and-review plan promotes toxicity and resistance while delaying the real diagnosis.
03
Using ciprofloxacin as an automatic default ignores the current MHRA restriction and the patient-specific risks of disabling adverse effects.
04
Closing a defunctioning ileostomy before a leak cavity or sinus has healed can convert contained sepsis into a major clinical failure.
05
Promising normal bowel function after a pouch prevents meaningful consent about night-time frequency, seepage, fertility, sexual function and possible pouch failure.

Find your next topic