Etiologies and outcomes of pleural effusions in patients with systemic lupus erythematosus.

BACKGROUND

Pleuritis is the most common pulmonary manifestation in systemic lupus erythematosus (SLE). In Thailand, the incidence of tuberculosis (TB) is high; moreover, treatment with immunosuppressive agents increases the risk for TB infection.

OBJECTIVE

The objective of this study was to examine the clinical manifestations, etiology, management, and outcomes of patients with SLE and pleural effusion in an area for TB.

METHODS

We studied adults satisfying the American College of Rheumatology classification criteria for SLE who presented with pleuritis between 2002 and 2010. Pleuritis was defined as having 1 of 3 of the following criteria: typical pleuritic chest pain, pleural rub, and clinical or radiological evidence of pleural effusion.

RESULTS

A total of 119 patients with 127 episodes of pleuritis/pleural effusion were included. Pleuritis was the first presentation in 47 episodes (37%) and was found accompanied with pericarditis for 16%. Most patients (81%) had active SLE in other systems. The causes of pleural effusion included lupus pleuritis (52%), tuberculous pleuritis (9%), parapneumonic effusion (7%), and transudate (15%). The diagnosis was inconclusive in 17%. The diagnosis of lupus pleuritis was made by a clinical diagnosis (47%) and by excluding other causes from pleural fluid analysis or biopsy (53%). Most patients with lupus pleuritic responded well to corticosteroid therapy.

CONCLUSIONS

Lupus pleuritis is still the most common cause of pleural effusion in SLE and often reflects its disease activity. The diagnosis of lupus pleuritis is a clinical diagnosis or is performed by excluding other conditions. The treatment outcomes of lupus pleuritis are generally good.