Rigler Sign in a Child With Posttransplant Lymphoproliferative Disease: A Sign That Should Not Be Missed.

Rigler sign is a double wall sign suggesting pneumoperitoneum and intestinal perforation, and it needs emergency surgical treatment. Early diagnosis of intestinal perforation by clinical symptoms, presence of Rigler sign in abdominal radiography, and then early surgical treatment can reduce mortality. Here, we report a patient with Crigler-Najjar syndrome who underwent liver transplant and then developed posttransplant lymphoproliferative disease and received chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab. She was referred to the emergency department due to abdominal distension with positive Rigler sign in abdominal radiography; intraoperative findings revealed intestinal perforation. Pediatricians and surgeons should be aware of Rigler sign so that it is diagnosed early and emergency surgical treatment can be performed.