Arthritis and collagenous colitis. Report of a case with concomitant chronic polyarthritis and collagenous colitis.

A 26-year-old woman simultaneously developed chronic seronegative non-destructive polyarthritis and chronic watery diarrhoea. Biopsies from the colorectal mucosa showed a thickened subepithelial collagen layer consistent with collagenous colitis. The combination of these conditions has not, to our knowledge, been described previously. On the basis of only one patient it is too early to determine whether or not this case represents a new type of enteropathic arthritis.