Bronchiolitis obliterans with organizing pneumonia in rheumatoid arthritis--a fatal case and short review of literature.

Bronchiolitis obliterans with organizing pneumonia (BOOP) is characterized by excessive proliferation of granulation tissue within small airways (proliferative bronchiolitis) and alveolar ducts associated with chronic inflammation in the surrounding alveoli. It is generally idiopathic but may occur during the resolution of viral or mycoplasmic pneumonia. It is also associated with a variety of systemic illnesses and clinical settings. Complete resolution occurs in 65-85% of patients treated with corticosteroid therapy, and recurrence is not uncommon. Although rapidly fatal BOOP is rare, respiratory failure leading to death may occur in up to 5% of patients. We describe a fatal case of BOOP suspicious for pneumonia in a patient with rheumatoid arthritis.