SLS

Q: Shrinking lung syndrome (SLS) is a phenomenon occurs in? (select one)

A) Interstitial lung disease (ILD)

B) Systemic Lupus Erythematosus (SLE)

Answer: B

Reflexly, it may occur to answer SLS as an integral part of ILD. However, it occurs in SLE with the provision that there is no evidence of underlying ILD on a CT scan. Some of the other features as expected are dyspnea, episodic pleuritic pain, and progressive decrease in: 

• lung volumes
• diffusing capacity for carbon monoxide (DLCO)
• forced vital capacity (FVC) but normal ratio of forced expiratory volume in one second [FEV1]/FVC) - restrictive pattern
• pulmonary function tests (PFTs).

If it occurs in SLE patients, the average time is about four years from the time of diagnosis.

No established cause has been found yet, but the presumed mechanism is myositis/myopathy causing elevation of the diaphragms. Another plausible hypothesis is that chronic pleural inflammation impairs the deep inspiration and leads to atelectasis, parenchymal reorganization, and decreased lung compliance.

Glucocorticoids, immunosuppressive therapy, Theophylline, and beta-adrenergic agonists may help.

#rheumatology

#pulmonary

References:

1. Karim MY, Miranda LC, Tench CM, et al. Presentation and prognosis of the shrinking lung syndrome in systemic lupus erythematosus. Semin Arthritis Rheum 2002; 31:289.

2. Warrington KJ, Moder KG, Brutinel WM. The shrinking lungs syndrome in systemic lupus erythematosus. Mayo Clin Proc 2000; 75:467.

3. Munoz ML, Gelber AC, Houston BA. Into thin air: shrinking lung syndrome. Am J Med 2014; 127:711.