Evaluation of respiratory manifestations in systemic lupus erythematosus with special reference to pulmonary interstitial involvement.

Different respiratory manifestations in systemic lupus erythematosus (SLE) are not uncommon. We lack sufficient Indian data in this regard. Forty diagnosed cases of SLE were evaluated, to find out the prevalence of respiratory manifestations in SLE, as also to correlate the findings as observed by different diagnostic methods. It was a single centre cross-sectional observational study conducted at rheumatology clinic, IPGME&R, Kolkata. Patients suffering from chronic airways obstruction, upper airway diseases, left ventricular failure and lung cancer were all excluded from the study. After clinical evaluation and routine testing of organ specific parameters, patients underwent spirometry and chest x-ray in all cases and pleural fluid study, pleural biopsy and high resolution CT scan of thorax selectively as required. Mean age at presentation was 26.8 years and female to male ratio was 39:1. Commonest respiratory symptom was dyspnoea and commonest respiratory manifestation was pleural effusion. Pleural effusion was bilateral in 80% of cases. Interstitial lung disease (ILD) was found in 10% of cases presented either subacutely or chronically. High resonance CT was found to be more sensitive to diagnose ILD, as in 50% of ILDs diagnosed by scan, chest x-rays were normal. Pleuropulmonary infections (7.5%) were next most common manifestation and tuberculosis was found to be the commonest cause. Lupus pneumonitis was found in one only (2.5%). Screening lung function test as done by spirometry, could pick up some abnormality in 50% cases and restrictive change was the major abnormality (47%). None showed evidence of bronchial hyper-responsiveness. No case was detected to have neuromuscular disease, acute respiratory distress syndrome or pulmonary thrombo-embolism. All the respiratory manifestations as noted appeared in variable period after the onset of SLE.