Leprosy rash precipitated by immunotherapy for suspected inflammatory neuropathy.

Leprosy is a chronic granulomatous infection caused by Mycobacterium leprae complex, causing skin and nerve lesions with potential for permanent disability. Leprosy can be overlooked in Western settings, as it is more prevalent in low-income and middle-income countries. We describe a 38-year-old woman with a 4-year history of progressive numbness of the left hand incorrectly diagnosed as multifocal acquired demyelinating sensory and motor neuropathy on the basis of clinical and neurophysiological findings. Treatment with empirical weekly corticosteroid followed by intravenous immunoglobulin resulted in the sudden development of a widespread rash; we then diagnosed borderline lepromatous leprosy on skin biopsy. We postulate that the immune treatments induced a temporary state of immune tolerance followed by a rebound of a T cell-mediated immune response resulting in a type 1 immunological response.

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.