Three cases of pneumatosis intestinalis presenting in autoimmune diseases.

Pneumatosis intestinalis (PI) is a comparatively rare disease characterized by the presence of intramural gas in the gastrointestinal tract. PI is known to be associated with several clinical conditions, such as pulmonary diseases, gastrointestinal diseases, and traumatic injury, as well as autoimmune disorders. In particular, PI is commonly seen in systemic sclerosis (SSc) but rarely in systemic lupus erythematosus and dermatomyositis (DM). In this report, we present three cases of PI presenting in autoimmune diseases, including DM, Sjögren's syndrome, and limited SSc, and further discuss its background characteristics.