First Reported Successful Use of Infliximab Maintenance Therapy for Dual Treatment of Crohn Disease and Idiopathic Retroperitoneal Fibrosis.

This case report describes the novel use of infliximab as maintenance therapy for both Crohn disease and idiopathic retroperitoneal fibrosis in a patient with concurrent disease. A 34-year-old man with Crohn disease developed a pelvic mass and hydroureteronephrosis, leading to an idiopathic retroperitoneal fibrosis diagnosis. Given shared inflammatory pathways, he was treated with prednisone followed by infliximab. Post-treatment imaging showed mass reduction and hydronephrosis improvement. After 1 year, he remains stable. This case highlights infliximab's potential in managing both conditions, presenting a unique therapeutic approach. Further studies are needed to evaluate its broader application in dual pathology.