Pneumatosis intestinalis in association with connective tissue disease.

Pneumatosis intestinalis in association with connective tissue diseases is an unusual combination whose pathogenesis is not yet understood. Furthermore, steroid medication, often used to treat these diseases, may itself cause pneumatosis. Three cases of scleroderma, systemic lupus erythematosus, and amyloidosis in association with pneumatosis and without prior steroid therapy are presented. The small vessel occlusive pathologic processes in these diseases may cause focal areas of mucosal ischemia resulting in small, perhaps transient ulcerations that allow gas to enter the gut wall from the lumen.