Object: Gastrointestinal involvement in adult dermatomyositis (DM) and polymyositis (PM) is usually mild, resulting from myoenteric dismotility. Severe inflammation of the alimentary tract in cases of adult DM and PM is rare. The purpose of this study was to examine the prevalence and clinical characteristics of inflammatory gastrointestinal involvement in patients with DM.
Methods: The charts of all cases with polymyositis or dermatomyositis, registered in our rheumatology clinic between 1984 and 2004, were reviewed retrospectively for documentation of severe gastrointestinal involvement. The clinical course and the histopathologic findings in all the patients were noted, and the prevalence of this disorder was computed.
Results: Among 48 patients with DM or PM, 3 patients with DM and severe gastrointestinal tract manifestations were identified (6% of the study population). Edematous hyperemic bowel wall, with multiple erosions and ulcerous lesions were the prominent endoscopic findings, whereas diffuse mucosal inflammation and multiple vascular ectasias without vasculitis dominated the histologic picture. The resulting clinical course was notable for recurrent abdominal pain and bloody diarrhea, ending catastrophically in two patients with fatal gastrointestinal perforations, despite aggressive immunosuppressive therapy.
Conclusions: Severe inflammatory gastrointestinal tract disease should be recognized as a grave, albeit rare, manifestation of adult DM that portends a poor prognosis and carries a high rate of fatal complications. The role of vasculopathy in the pathogenesis of this syndrome remains to be determined.