A 74-year-old woman with rapidly progressing renal failure after an upper respiratory tract infection

A 74-year-old woman was admitted to the hospital with an upper respiratory tract infection and progressive kidney failure and was diagnosed with microscopic polyarteritis. Polyarteritis is a form of systemic vasculitis characterized by the inflammation and cell death of blood vessels and associated organs. The woman had suffered a heart attack 14 months prior to admission and had a history of congestive heart failure and valvular diseases. X-rays revealed that her heart was enlarged but that her kidneys were normal in size. The normal size of her kidneys and the reduction in her urine volume suggested that her kidney failure was an acute form, not chronic. The multi-system involvement further suggested that her rapidly progressive kidney failure was due to either a bacterial infection or systemic vasculitis. She tested positive for antibodies to the enzyme myeloperoxidase, which confirmed the diagnosis of systemic vasculitis. At autopsy, vasculitis was also detected in her kidneys.