Pulmonary Involvement in Systemic Lupus Erythematosus: A Hospital-Based Study from Western Rajasthan

Introduction: Systemic lupus erythematosus (SLE) can involve every compartment of the respiratory system, from pleura and parenchyma to pulmonary vessels, airways and respiratory muscles. Lung disease is often subclinical, and chest radiography and pulmonary function tests (PFT) may miss it. This study determined the prevalence and pattern of pulmonary involvement in SLE and compared the yield of chest X-ray, high-resolution computed tomography (HRCT) and PFT. Methodology: This prospective hospital-based study enrolled 50 patients with SLE (revised ACR criteria, age 18 to 60 years, disease duration of at least 5 years) at the Department of Medicine, Dr. S. N. Medical College, Jodhpur, from February to July 2023. Chronic smokers and patients with pre-existing lung disease, known cardiac disease or pregnancy were excluded. All patients underwent chest X-ray, HRCT chest and PFT, with laboratory and immunological work-up as needed. Results: Forty-six patients (92%) were women, and 35 (70%) were aged 20 to 40 years. Twenty-two patients (44%) had respiratory symptoms, most often pleuritic chest pain (24%) and dyspnoea (16%). HRCT was abnormal in 34 patients (68%), compared with 13 (26%) by chest X-ray and 7 (14%) by PFT, all of which showed a restrictive pattern. Pleural effusion (28%) and interstitial lung disease (ILD, 26%) were the commonest findings, followed by pneumonitis (6%), consolidation with effusion (4%) and mediastinal lymphadenopathy (4%). Half of the 28 asymptomatic patients had HRCT abnormalities. ILD was present in 10 of the 11 patients with disease duration of 21 years or more. Conclusion: Pulmonary involvement is common in SLE, and HRCT detects it in a large share of patients with normal chest X-ray and PFT, including patients without respiratory symptoms. HRCT chest should be considered even for subtle respiratory symptoms so that treatment starts before changes become irreversible.