Systemic lupus erythematosus (SLE) may affect all the components of the respiratory system, including upper airways, lung parenchyma, pulmonary vasculature, pleura, and respiratory muscles. The shrinking lung syndrome (SLS) is a rare complication of SLE. This study describes the presenting features, investigation findings, treatment measures, and outcome of 7 patients with SLE and SLS.
Five patients with SLE/SLE were chosen retrospectively by examination of patient records, and 2 patients were chosen prospectively. All patients attended St. Thomas' Hospital or the Royal London Hospital between 1984 and 2001, with a total population of 2650 patients with SLE.
Clinical features included dyspnea and pleuritic chest pain. Chest x-ray films showed small but clear lung fields, or basal atelectasis, with diaphragmatic elevation. No evidence of major parenchymal lung or pleural disease was found on the computerized tomography scan. Lung volumes were reduced on pulmonary function testing (PFT) in a restrictive pattern. Treatment of SLS included theophylline, increase in corticosteroid dosage, and intensification of immunosuppressive medication to include methotrexate or cyclophosphamide. During follow-up, 5 of 7 patients showed objective evidence on PFT of stabilization or improvement.
SLS represents a rare complication of SLE, and it is important to be aware of its presenting features and prognosis.
The long-term prognosis of our SLS patients was reasonable, highlighting the importance of establishing a correct diagnosis and in particular differentiating it from fibrosing lung disease. Immunosuppressive therapy was helpful in stabilizing SLS and improving respiratory symptoms and PFT in some cases.