Pouchitis is inflammation of the ileal pouch, which is created in the management of patients with ulcerative colitis, indeterminate colitis, FAP, or, rarely, other colitides. A variety of pathophysiological mechanisms have been proposed for pouchitis, but the precise pathogenesis remains unknown. A pilot study on the effect of reducing dietary FODMAP intake on bowel function in patients without a colon ran by Croagh C, Shepherd SJ, Berryman M, Muir JG, Gibson PR indicates there might be a relation between Pouchitis and FODMAP content of diets. The incidence of a first episode of pouchitis at 1, 5 and 10 years post-operatively is 15%, 33% and 45% respectively. Patients with pouchitis typically present with bloody diarrhea, urgency in passing stools, or discomfort while passing stools. The loss of blood and/or dehydration resulting from the frequent stools will frequently result in nausea. Extreme cramping and pain can occur with pouchitis. Endoscopy in patients with pouchitis usually reveals erythematous pouch mucosa, loss of pseudocolonic vasculature or other architecture, and friability of the mucosa. Biopsies show evidence of inflammatory cells or red blood cells in the lamina propria.
Classification
Once a diagnosis of pouchitis is made, the condition is further classified. The activity of pouchitis is stratified as:
remission.
mild to moderately active.
severely active.
The duration of pouchitis is defined as acute or chronic and the pattern classified as infrequent, relapsing or continuous. Finally, the response to medical treatment as labelled as treatment responsive or treatment refractory, with the medication for either case being specified.
Signs and symptoms
Symptoms of pouchitis include Increased stool frequency, urgency, incontinence, nocturnal seepage, abdominal cramping, pelvic discomfort, and arthralgia. Symptom severity does not always correlate with severity of endoscopically- or histologically-evaluated pouch inflammation. Additionally, these symptoms are not necessarily specific for pouchitis, as they may arise from other inflammatory or functional pouch disorders such as Crohn's disease of the pouch, cuffitis, pouch sinus, or irritable pouch syndrome. The most reliable tool for diagnosis is endoscopy combined with histologic features.
Diagnosis
Treatment
There is no clinically approved treatment for pouchitis. First line treatment is usually with antibiotics, specifically with ciprofloxacin and metronidazole. Ampicillin or piperacillin can also be considered as alternatives to empiric ciprofloxacin and metronidazole. Administration of metronidazole at a high daily dose of 20 mg/kg can cause symptomatic peripheral neuropathology in up to 85% of patients. This can be a limiting factor in the use of maintenance metronidazole to suppress chronic pouchitis. Other therapies which have been shown to be effective in randomised clinical trials include probiotic therapy, the application of which usually begins as soon as any antibiotic course is completed so as to re-populate the pouch with beneficial bacteria. Biologics, such as anti-TNF antibodies, may also be useful but the evidence for their use is largely anecdotal. In addition, discussion by patients using related internet forums appears to give evidence of benefits from certain diets, such as the Specific Carbohydrate Diet, Paleolithic Diet, and low-FODMAP diet. In particular, attention has been drawn to the exclusion of complex carbohydrates, as well as other foods with high starch content and certain dairy products including milk and soft cheese.
