Is there a myoelectrical abnormality in the irritable colon syndrome?

Although recent work has suggested that an abnormality of the 0.05 Hz (3 c/m) slow wave electrical activity exists in the distal colon of patients with the irritable colon syndrome, it is not established whether this is related to altered bowel habit alone, or whether it is specific to the irritable colon syndrome. We have therefore studied 10 patients referred with this disorder and compared their colonic myoelectrical pattern with 10 patients suffering from assorted disorders with similar symptoms--for example, chronic pancreatitis, diverticular disease, ulcerative colitis, etc. Transit time, stool weights, percentage motility, and slow wave electrical activity were measured in each patient. The two groups were well matched for age and patients with similar symptoms in the two groups had similar values for transit time and percentage motility. There was a statistically significant increase in the 3 c/m electrical activity in patients with the irritable colon syndrome unrelated to the degree of diarrhoea or constipation. It would appear, therefore, that the abnormally high incidence of 3 c/m electrical activity in the colon is specific to the irritable colon syndrome and not merely a feature of altered bowel habit.