A Case Report of Diffuse Alveolar Hemorrhage Coexisting With Immunoglobulin A (IgA) Nephropathy.

Immunoglobulin A (IgA) nephropathy is the most common cause of primary glomerulonephritis worldwide. IgA vasculitis (formerly known as Henoch-Schonlein purpura) typically presents with IgA nephropathy on renal biopsy in addition to extrarenal symptoms like purpura, abdominal pain, and arthritis. Diffuse alveolar hemorrhage (DAH) is the most common pulmonary complication, but this is rarely seen. In this case report, we describe a 35-year-old male with chronic untreated hepatitis B infection who presented with pulmonary-renal syndrome. He was found to have clinical findings of DAH and concomitant IgA nephropathy on renal biopsy, without having any other typical manifestations of IgA vasculitis. This shows that IgA nephropathy should be considered in the differential diagnosis of DAH and emphasizes the importance of a renal biopsy in patients presenting with pulmonary-renal syndrome.