Anti-centromere antibody-positive primary Sjögren's disease with exudative pleural effusion: A case report and literature review.

Sjögren's disease (SjD) is a systemic autoimmune disorder with glandular and extra-glandular manifestations. Pleural effusion is a rare complication of SjD among different types of pulmonary involvement. Herein, we report a case of primary anti-centromere antibody (ACA)-positive primary SjD with pleural effusion. A 79-year-old woman was admitted to our hospital with a 3-month history of leg oedema. She was diagnosed with primary SjD based on positive Schirmer and Saxon tests, and her anti-Sjögren syndrome-related antigen/Ro antibody test was negative, but ACA and anti-Sjögren syndrome-related antigen B/La tests were positive. The patient's symptoms promptly improved following prednisolone treatment. This is the first reported case of ACA-positive primary SjD complicated with pleural effusion, and the possible presence of pleural effusion should be considered in SjD, even in patients with ACA-positive primary SjD.