Pleuropulmonary abnormalities in patients with systemic lupus erythematosus: assessment with high resolution computed tomography, chest radiography and pulmonary function tests.

OBJECTIVE: To assess the nature of pleuropulmonary abnormalities, with particular reference to interstitial lung disease (ILD), in patients with systemic lupus erythematosus (SLE).

METHODS: 29 patients were prospectively evaluated using high resolution computed tomography (HRCT), plain chest radiography (CXR) and pulmonary function tests (PFTs). Clinical assessments, drug therapy, disease activity, smoking status and serologic markers were also noted.

RESULTS: The HRCT was abnormal in 72% (20/29) of patients, while 34% (10/29) had an abnormal CXR. The most frequently detected primary HRCT abnormality was suggestive of ILD and was noted in 11 patients (38%) In 9 of these, ILD was clinically unsuspected, including one patient who had an HRCT suggestive of active alveolitis. Pleuropericardial abnormalities were seen on HRCT in 5 patients (17%). Of 15 patients who were asymptomatic, and had a normal examination, normal CXR and normal PFTs, four (26%) had HRCT features of ILD. There was no correlation between the HRCT appearances and symptoms, disease duration, ds-DNA titres, smoking history or non-pulmonary involvement. Although no statistical significance was noted between abnormal pulmonary function tests and ILD on HRCT (0.10 < p < 0.20), a trend towards significance was noted between disease activity and ILD (0.05 < p < 0.01).

CONCLUSION: HRCT is more sensitive than PFTs or CXR in the evaluation of pleuropulmonary disease in SLE. We report an unusually high prevalence of HRCT appearances suggestive of ILD in patients with SLE. Subclinical lung disease is common in patients with SLE.