Pulmonary function and high‐resolution CT findings five years after disease onset in patients with Wegener's granulomatosis

Abstract

Objective: Although pulmonary involvement is common in Wegener's granulomatosis (WG), little is known about the pulmonary outcome. We evaluated the relationship between clinical disease characteristics and pulmonary function and high‐resolution computed tomography (HRCT) findings after disease duration of 5 years.Methods: A pulmonary function test (PFT) and pulmonary HRCT were performed in 41 patients from a population‐based register of WG. Clinical predictors for abnormal PFT and HRCT were tested by logistic regression.Results: Previous WG‐related lung involvement (PLI) had occurred in 80% of patients, but only 24% of patients still reported pulmonary symptoms at the research visit. One‐third of patients had abnormal PFT findings, with reduced alveolar diffusion by KCO (transfer coefficient) being most common (24%). The number of PLI episodes was associated with reduced KCO and reduced FEV1% (forced expiratory volume in 1 s as a percentage of forced vital capacity) (overall presence 10%). Reduced KCO was also associated with disease duration. Reduced total lung capacity (TLC) (overall presence 8%) was only related to prior WG‐related lung nodules. Pulmonary HRCT was abnormal in 80%, but with more severe abnormalities in only 30%. Pleural thickening and parenchymal bands were associated with PLI. None of the treatment variables was associated with the PFT or HRCT findings.Conclusion: Five years after disease onset a quarter of the WG patients reported pulmonary symptoms, had severe abnormalities on HRCT, and abnormal PFT. The correlation between these abnormalities was poor, but the number of pulmonary involvements was a risk factor for reduced gas diffusion, obstructive lung disease, parenchymal bands, and pleural thickening. Treatment variables had no discernible negative pulmonary effects.