Pneumatosis intestinalis in juvenile dermatomyositis

Pneumatosis intestinalis (PI) is a rare condition of unknown etiology characterized by multiple gas-distended cysts in the submucosa of the colon and small intestine. PI has been reported in patients with collagen disorders, particularly scleroderma and juvenile rheumatoid arthritis. However, PI in association with juvenile dermatomyositis (JDMS) is very rare and only 5 cases are reported in the literature. A 7-year old African-American female with JDMS on oral prednisolone (45 mg/day) and low-dose intramuscular methotrexate (12.5 mg once a week) presented with a 2-day history of abdominal pain and decreased appetite. On admission she was ill-looking with a temperature of 100.7° F, a heart rate of 148 beats/min, a respiratory rate of 24 breaths/min, and a blood pressure of 135/86 mm Hg. Physical examination revealed Gottron's papules, vasculitic ulcers in the axillae, and minimal proximal muscle weakness in the upper and lower limbs. Mild distension of the abdomen with tenderness on palpation in the right lower quadrant was noted. Laboratory data included an elevated ESR of 47 mm/hr, serum aldolase of 4.4 U/L (normal, 1.0-10.0 U/L), LDH elevated at 1050 U/L (normal, 370-840 U/L), and CPK of less than 20 U/L (normal, 30-135 U/L). No occult blood in the stool was noted. A plain radiograph of the abdomen revealed intramural air in the ascending and transverse colon. Conservative management with antibiotics and parenteral nutrition resulted in radiological resolution of the PI after 3 days, and clinical improvement evident after a week. The pathogenesis of PI in JDMS is not clear, although vasculitis of the gastrointestinal tract is a possibility. PI should be included in the differential diagnosis of a child with JDMS presenting with abdominal complaints.