Abstract
Collagenous colitis (CC) is characterized by chronic secretory diarrhea with the apparently
normal gross appearance of the colonic mucosa. A biopsy is usually diagnostic. The
symptoms of CC appear most commonly in the elderly. In CC, the major microscopic characteristic
is a thickened collagen layer beneath the colonic mucosa. The reported case represents
unexplained nonbloody diarrhea of a systemic lupus erythematosus patient, on extensive
evaluation found to have CC. This case highlights the importance of considering a
rare possibility of CC as a differential in a patient of unexplained nonbloody diarrhea.
Key words
Collagen colitis - microscopic colitis - nonbloody diarrhea
