Cystic Lung Disease Among Patients With Sjögren Syndrome: Frequency, Natural History, and Associated Risk Factors.

BACKGROUND: Cystic lung disease (CLD) in Sjögren syndrome (SS) is a condition with unclear prognostic implications. Our objectives in this study are to determine its frequency, progression over time, and associated risk factors and complications.

METHODS: Eighty-four patients with primary or secondary SS and chest imaging, chest radiograph, or CT scan were retrospectively evaluated for CLD. Thirteen patients with cysts were found. Baseline characteristics of all patients were collected. A multivariate logistic regression model was used to look for predictors of CLD in patients with CT scan. Additional imaging, SS activity, and complications from CLD and SS were collected for the patients with cysts.

RESULTS: CLD had a frequency of 15.4% for all patients with chest imaging. Not all cysts were evident on radiography, and CLD frequency was 30.9% for the patients with chest CT scan. Six patients had cysts without other radiographic findings. CLD was associated with older age (OR, 1.1; 95% CI, 1.0-1.16), a diagnosis of secondary SS (OR, 12.1; 95% CI, 1.12-130.4), and seropositivity for anti-SS-related antigen A/Ro autoantibodies (OR, 26.9; 95% CI, 1.44-93.61). There was no radiologic progression of CLD for 12 patients after a 4-year median follow-up. Lung function did not exhibit temporal worsening. CLD did not correlate with a specific pattern in pulmonary function testing. Two patients had secondary infectious complications of the cysts.

CONCLUSIONS: CLD is a relatively common condition in SS that does not progress on serial radiologic and lung function follow-up. CLD, without other radiographic findings, may represent a direct manifestation of SS.