Postinfective irritable bowel syndrome with diarrhoea and idiopathic b
ile acid malabsorption remains an enigma. We examined the records of 8
4 patients whose (75)SeHCAT scans were indicative of bile acid malabso
rption (<15% one week retention). Identifiable causes of bile acid mal
absorption were: previous ileal surgery (7), Crohn's disease (22), rad
iation enteritis (13), vagotomy, gastrectomy or cholecystectomy (10) a
nd miscellaneous (3). Sixteen of 29 patients with apparently idiopathi
c bile acid malabsorption gave a clear history of acute gastroenteriti
s before the onset of chronic diarrhoea lasting from 0.25-18 years unt
il their positive (75)SeHCAT scan. Only four cases of campylobacter, a
nd one each of shigella and salmonella were documented. Extensive inve
stigation failed to detect other possible pathologies. In response to
bile acid sequestrants, mean stool frequency fell from 7.2 per day to
2.1 per day (p < 0.001). We have observed that postinfective chronic d
iarrhoea is associated with chronic bile acid malabsorption, which can
be successfully treated with bile acid sequestrants such as cholestyr
amine.