Image of the month: Ormond's disease: A diagnostic challenge.

Idiopathic retroperitoneal fibrosis is a rare disease. Symptoms include constitutional symptoms and abdominal/flank pain. Causes of retroperitoneal fibrosis include non-infectious and infectious etiologies. Of the infectious etiologies, tuberculous aortitis is an important differential as it is associated with a high mortality rate. We present a case of a 59-year-old man with a retroperitoneal periaortic mass initially diagnosed as tuberculous aortitis. However following biopsy, the diagnosis was later amended to idiopathic retroperitoneal fibrosis with latent tuberculosis. He was successfully treated with prednisone and methotrexate. © Royal College of Physicians 2020. All rights reserved.