Diffuse alveolar hemorrhage in a patient with ankylosing spondylitis

Ankylosing spondylitis (AS) primarily affects the spine and axial skeleton. Various pulmonary manifestations have been reported; however, diffuse alveolar hemorrhage (DAH) has not been previously described in a patient with AS. A 49-year-old man with longstanding AS visited our hospital complaining of progressive dyspnea and hemoptysis. DAH was diagnosed based on the findings of chest computed tomography and bronchoscopy. No positive findings suggested any cause of DAH other than weakly positive results for perinuclear antineutrophil cytoplasmic antibodies on indirect immunofluorescence. Following the administration of steroid and plasmapheresis therapy, the patient's symptoms and chest radiographic findings improved. Further clinical case reports and investigations are needed to clarify whether DAH represents a possible pulmonary manifestation of AS.