title: Characteristics of pleural effusions in systemic lupus erythematosus: differential diagnosis of lupus pleuritis.
abstract: We investigated the clinical characteristics of pleural effusion in systemic lupus erythematosus (SLE). A prospective analysis of 17 SLE patients with pleural effusion (seven lupus pleuritis, eight transudative effusions and two parapneumonic effusions) was performed. Thirty non-SLE patients with pleural effusion were recruited as controls. A pleural fluid ANA titer ≥1:160 was found in 8/17 (47.1%) SLE patients and none of the 30 non-SLE patients (p = 0.0001). Pleural fluid to serum C3 ratios were significantly lower in SLE than in non-SLE (median (minimum-maximum) 0.29 (0.03-0.43) versus 0.52 (0.26-0.73), p = 0.0002). Among SLE patients, pleural fluid ANA titers ≥1:160 were more frequently found in patients with lupus pleuritis than in those with pleural effusion from causes other than lupus itself (85.7% versus 20.0%, p = 0.0152). Serum CRP levels were significantly increased in patients with lupus pleuritis compared with SLE patients with transudative pleural effusion (2.30 (0.30-5.66) versus 0.7 (0.12-1.47) mg/dl, p = 0.0062). In conclusion, pleural fluid ANA titer and serum CRP levels are significantly increased in lupus pleuritis.
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: B Y
authors.initials: BY
authors.lastname: Choi
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: M J
authors.initials: MJ
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Seoul National University Borame Medical Center, Seoul, Korea.
authors.forename: K
authors.initials: K
authors.lastname: Shin
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam-si, Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea Department of Molecular Medicine and Biopharmaceutical Sciences, Medical Research Center, Seoul National University College of Medicine, Seoul, Korea ysong@snu.ac.kr.
authors.forename: Y W
authors.initials: YW
authors.lastname: Song
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000150:complications* / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D010998:Pleurisy / Q000175:diagnosis / Q000209:etiology*; D011446:Prospective Studies; D055815:Young Adult
keywords: C-reactive protein; Systemic lupus erythematosus; anti-nuclear antibody; complement; lupus pleuritis; pleural effusion