CT Findings of Pulmonary Involvement in Antiphospholipid Syndrome

Aims: Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by vascular thrombosis. Pulmonary changes regarding interstitium and airways have not been described in APS. Our aim was to determine the prevalence of nonthrombotic pulmonary CT manifestations in patients with APS.
Study Design: Prospective study.
Place and Duration of Study: Department of Pneumonology, First Department of Internal Medicine, Department of Cardiology, Department of Radiology Medicine, between June 2009 and May 2011.
Methodology: Ten patients who met criteria for APS (5 primary and 5 secondary to systemic lupus erythematosus) were prospectively identified. All patients underwent chest high-resolution computed tomography (HRCT) and functional assessment including spirometry and 6-minute walking distance. Patients were free of respiratory symptoms. HRCT scans were evaluated for presence of air-trapping, subpleural reticular pattern, centrilobular nodules of ground-glass opacity, cysts, emphysema, atelectasis, consolidation and pleural effusion. Extent of air-trapping was estimated based on a HRCT scoring system.
Results: All patients exhibited radiological and functional pattern compatible with small-airway disease, irrespective of smoking status. HRCT findings were negatively correlated with reduced levels of maximum midexepiratory flow (MMEF) 25/75%pred (r=-0.936, p<0.0001). Subpleural basal reticular pattern consistent with fibrosis was seen in 3 patients. Thin-walled cysts and upper-lobe hazy micronodular pattern were detected in 4 patients.
Conclusion: CT findings of patients with APS may include air-trapping, subpleural reticular pattern, centrilobular nodules of ground-glass opacity and lung cysts irrespective of smoking history and SLE coexistence. HRCT and functional assessment may be valuable tools in evaluating APS patients.