A study on pulmonary complications of systemic sclerosis in eastern India.

AIM: This study was undertaken to find out the characteristics of clinical, radiological and functional changes affecting the respiratory system in patients with systemic sclerosis (SSc) from eastern India, and the association of these characteristics with pulmonary hypertension.

METHODS: This was a cross-sectional, observational study involving 46 patients. Other than the routine tests, anti-nuclear antibody (ANA), spirometry, diffusing capacity of lung for carbon monoxide (DLCO) measurement, chest radiograph, high-resolution computed tomography (HRCT) of thorax, 6-minute walk test and echocardiography were done.

RESULTS: Out of a total of 46 patients, 27 patients had diffuse cutaneous SSc (dcSSc) and 19 had limited cuteaneous SSc (lcSSc). Eleven patients had pulmonary hypertension. The HRCT revealed diffuse parenchymal lung disease (DPLD) in 32 (65%) cases. The ANA was positive in 83% cases. Anti-Scl70 was found in 41% of patients with dcSSc and anti-centromere antibody was found in 47% of patients with lcSSc. Spirometry revealed restrictive pattern in 30 patients; 9 had obstruction; and the rest were normal. The DLCO was abnormal in 38 patients. A strong correlation was found between reduction in DLCO and pulmonary artery systolic pressure (PASP). Also, a strong association was observed between a drop of > 4% in oxygen saturation on 6-minute walk test and presence of pulmonary arterial hypertension (PAH).

CONCLUSIONS: Majority of the patients with SSc had restrictive lung disease with abnormal DLCO and features resembling non-specific interstitial pneumonia. Nucleolar ANA was predominantly found in patients having PAH. Presence of DPLD had a negative association with presence of anti-centromere antibody. Reduction in DLCO and a fall of > 4% in oxygen saturation on 6-minute walk test may be used as predictors of PAH in asymptomatic individuals.