Thoracic Imaging Findings in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease with frequent thoracic involvement, contributing significantly to morbidity and mortality. Computed tomography (CT) plays a vital role in detecting and characterising thoracic manifestations of SLE. The aim of this study was to evaluate the spectrum of thoracic manifestations of systemic lupus erythematosus using CT.

This prospective cross-sectional observational study was conducted in the Department of Radiodiagnosis at Nizam's Institute of Medical Sciences, Hyderabad, over a period of 18 months (November 2022 to April 2024). Sixty adult patients diagnosed with SLE and referred for chest CT were included. High-resolution CT, contrast-enhanced CT, or CT pulmonary angiography was performed based on clinical indication. The primary outcome measured was the spectrum and frequency of thoracic manifestations of SLE identified on CT imaging, along with associated extra-thoracic findings. Descriptive statistical analysis was performed, and results were expressed as frequencies, percentages, and means with standard deviations.

The study population had a mean age of 31.8 ± 9.9 years, with a marked female predominance (n=50, 83.3%). Infection was the most common thoracic diagnosis, identified in 32 patients (53.3%), predominantly bacterial in origin (n=27, 45%). Pulmonary arterial hypertension was observed in 30 patients (50%), followed by pulmonary oedema in 11 patients (18.3%). Interstitial lung disease (ILD) and serositis were each noted in 6 patients (10%), with nonspecific interstitial pneumonia being the most frequent ILD pattern (n=4, 6.6%). Less frequent findings included pulmonary thromboembolism (n=3, 5%), lupus pneumonitis (n=2, 3.3%), and diffuse alveolar haemorrhage (n=2, 3.3%). Splenomegaly was the most common additional finding (n=31, 51.7%).

Thoracic involvement in SLE is diverse, with infections and vascular manifestations being the most frequent. CT imaging plays a crucial role in identifying overlapping thoracic patterns, facilitating accurate diagnosis and guiding appropriate clinical management.