Collagenous colitis (CC) is an inflammatory bowel condition of unknown etiology. Systemic sclerosis (SSc) has been associated with CC in a few cases, but it is not clear whether CC could be considered an unusual manifestation of SSc or an independent condition. Here we present a case of SSc-associated CC and compare routine histology and immunofluorescence studies for allograft inflammatory factor 1 and caveolin 1 expression with other cases of CC and healthy controls. All CC biopsies showed characteristic sublaminal collagen accumulation and a decrease of caveolin 1 expression, this latter finding consistent with and common in any fibrotic reaction. In contrast, the expression of allograft inflammatory factor 1 was increased only in the SSc-CC specimen, suggesting a distinct pathogenesis. A literature review revealed 6 previously reported cases of SSc-CC with common clinical features. These observations suggest that CC should be suspected as a rare gastrointestinal complication of SSc and that clinicians should be aware of the possibility in SSc patients developing watery diarrhea.
From the *Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds; and †NIHR Leeds Musculoskeletal Biomedical Research Unit and ‡Department of Histopathology, St James’s University Hospital, Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom; and §Department of Rheumatology, University of Lund, Lund, Sweden.
Sources of support: GA is funded by NIHR Leeds Musculoskeletal Biomedical Research Unit.
The authors declare no conflict of interest.
Correspondence: Giuseppina Abignano, MD, PhD, Chapel Allerton Hospital, 2nd Floor, Chapeltown Rd, Leeds, United Kingdom LS7 4SA. E-mail: email@example.com.