Impact of bile acid malabsorption on steatorrhoea and symptoms in patientswith chronic diarrhoea

Objective Bile acids are important for fat absorption. The relationship bet ween bile acid malabsorption and steatorrhoea and gastrointestinal symptoms in patients with chronic diarrhoea has only been studied on a limited scal e. Design Ninety-four patients referred for chronic diarrhoea were prospective ly investigated with the (75)SeHCAT test, a faecal fat excretion test and r egistration of symptoms in addition to the standard clinical work-up. Methods The correlation between the (75)SeHCAT value and the faecal fat exc retion was calculated for different groups of patients. Symptoms were regis tered in a questionnaire over a period of seven consecutive days. Results Forty-two patients had a (75)SeHCAT value <10%. Mild steatorrhoea w as common in patients with nonorganic bile acid malabsorption (50%) and in patients with functional diarrhoea (38%). There was no correlation between low (75)SeHCAT values and steatorrhoea, although some patients with severe organic disease had a concomitant malabsorption of fat and of bile acids. I n coeliac disease, severe steatorrhoea was common even in patients with hig h (75)SeHCAT values. Patients with bile acid malabsorption had more frequen t (P < 0.008) and looser (P = 0.0021) stools compared with patients with fu nctional diarrhoea. There was no difference in abdominal pain, distension o r flatulence. Conclusion Mild steatorrhoea is common in both nonorganic bile acid malabso rption and functional diarrhoea. The (75)SeHCAT value cannot predict the ri sk of steatorrhoea. The high prevalence of bile acid malabsorption in patie nts with chronic diarrhoea and the absence of specific symptoms, except fre quent and more liquid stools, indicates that the (75)SeHCAT test should be performed early in the investigation of these patients. (C) 2000 Lippincott Williams & Wilkins.