Acute fibrinous and organizing pneumonia as initial presentation of primary Sjögren's syndrome: a case report and literature review.

Acute fibrinous and organizing pneumonia (AFOP) is a new histopathological pattern of acute lung injury first described by Beasley et al. in 2002. Hallmarks of pathological findings are characterized by the presence of intra-alveolar fibrin in the form of fibrin "balls" within the alveolar spaces and organizing pneumonia with a patchy distribution. Patients with AFOP may have an acute or subacute clinical presentation. Although the pathogenesis of AFOP is not fully elucidated, it may be associated with autoimmune diseases. Reported herein is a patient diagnosed of acute AFOP associated with primary Sjögren's syndrome. The patient's condition promptly improved after treatment with corticosteroid.