Collagenous colitis and sacroiliitis: a case report and literature review.

The seronegative spondyloarthropathies commonly occur in association with such enteropathic disorders as inflammatory bowel disease, enteric infections, and Whipple's disease. Only 3 cases of collagenous colitis have been reported in association with spondyloarthropathy. We describe a 51-year-old patient with bilateral sacroiliitis and collagenous colitis, who presented with chronic, recurrent low back pain, morning stiffness, and diarrhea. As with two of the three reported cases, we describe musculoskeletal complaints preceding the onset of diarrhea. The late occurrence of suggestive diagnostic features such as diarrhea may lead to a delay in the diagnosis of a potential enteropathic arthropathy, as in our patient. All patients with chronic diarrhea should undergo appropriate evaluation with an eye for any attendant musculoskeletal features known to be potentially attributed to the resulting diagnosis. A variety of other rheumatologic and autoimmune illnesses have been described with collagenous colitis. Whether the association between collagenous colitis and seronegative spondyloarthritis is causal or casual remains to be determined. We encourage clinicians to report cases of collagenous colitis associated with spondyloarthropathy in hopes that this issue will be resolved.