The purpose of our study was to identify high-resolution CT (HRCT) findings in patients with systemic lupus erythematosus (SLE) and to determine their significance by correlation with clinical findings, plain chest radiography, and pulmonary function testing.
Thirty-four patients with documented SLE were prospectively studied. All patients had plain chest radiography (posteroanterior and lateral) thoracic spiral CT, HRCT, and pulmonary function testing performed.
HRCT abnormalities were identified in 24 patients (70%), pulmonary function abnormalities were present in only 14 patients (41%), and the plain chest radiograph was abnormal in only 8 patients (24%). The most common CT findings were: interstitial lung disease (n = 11), bronchiectasis (n = 7), mediastinal or axillary lymphadenopathy (n =6), and pleuropericardial abnormalities (n =5). No correlation was found between disease activity, duration of disease, chest symptoms, drug therapy, smoking history, and the presence of abnormal HRCT findings. More importantly, no correlation was found between pulmonary function abnormalities and the presence or grade of interstitial lung disease or bronchiectasis as determined by HRCT.
The results of this study, the first to describe the HRCT findings in SLE, suggest that airways disease, lymphadenopathy, and interstitial lung disease are common thoracic manifestations of SLE, whereas pleural abnormalities are less common than previously suggested. HRCT evidence of airways disease and interstitial lung disease was frequently present despite an absence of symptoms, a normal chest radiograph, and normal pulmonary function testing. HRCT provides a sensitive and noninvasive technique for detecting pulmonary involvement in SLE, with the added advantage that it can be performed in all patients, including those too compromised to undergo a surgical procedure. In patients with advanced disease, HRCT permits procedures such as bronchoalveolar lavage and lung biopsy to be directed toward areas of particular interest.