SHORT COMMUNICATIONS AND BRIEF CASE NOTES Collagenous Colitis in a Patient With Common Variable Immunodefi ciency

Collagenous colitis is a poorly understood condition associated with autoimmunity that results in watery, nonbloody diarrhea [1]. Common variable immunodefi ciency (CVID) is a heterogeneous group of antibody defi ciency disorders resulting in recurrent infection, autoimmunity, malignancy, and inflammatory complications [2]. CVID is diagnosed when there is a marked reduction in both immunoglobulin G and at least 1 other immunoglobulin isotype and a failure to respond to vaccination after exclusion of other causes of hypogammaglobulinemia [3]. Gastrointestinal manifestations are common although there has been just 1 report of an atypical presentation of collagenous colitis in CVID [4]. We describe a second case of a patient with CVID and typical features of collagenous colitis in whom fecal calprotectin was used as an infl ammatory marker. The condition was treated successfully with budesonide. A 25-year-old woman was diagnosed with CVID in 2000 and commenced on intravenous immunoglobulin therapy after presenting with recurrent sinopulmonary infections since childhood. She had a history of intermittent nonbloody diarrhea from the 1990s, with a weight loss of 5 to 10 kg in 1996. Several nondiagnostic colonoscopies were performed during that time, but it was not until 2001 that collagenous colitis was found. The patient declined steroid treatment and received cholestyramine instead. The diarrhea improved but in late 2004, the patient developed a fl are-up, with motions occurring 8 to 12 times a day. This was associated with a weight loss of 5 kg over 3 months. Stool samples were negative for common pathogens, including Giardia. The patient was treated empirically with metronidazole, which made no difference. Inflammatory markers (C-reactive protein and erythrocyte sedimentation Figure. Collagenous colitis. A thickened subepithelial eosinophilic plate consistent with collagen deposition confi rmed by Verhoeff-van Gieson staining for collagen. rate) were normal but fecal calprotectin was elevated at 395 μg/g (normal, < 60 μg/g). Colonic biopsies showed lymphoid hyperplasia without active infl ammation, and this was thought to be consistent with the patient’s CVID. Fecal calprotectin had fallen spontaneously to 108 μg/g by this stage and as there was no evidence of infl ammation, the patient was tried empirically on pancreatin (a mixture of lipase, protease and amylase) and various antibiotics, all of which were unhelpful. Her symptoms improved spontaneously in early 2006 but recurred towards the end of that year with diarrhea occurring more than 10 times a day. Fecal calprotectin levels rose to 252 μg/g and a repeat colonoscopy showed collagenous colitis (Figure).