Primary Sjögren's syndrome in dizygotic adolescent twins: one case with lymphocytic interstitial pneumonia.

Primary Sjögren's syndrome (pSS) is uncommonly recognized in childhood, and familial cases are rare. Pulmonary involvement in pediatric pSS is infrequently reported. In adults, asymptomatic pulmonary involvement is increasingly recognized, manifest by pulmonary function test abnormalities and changes on high resolution computerized tomographic scan. We describe a case of pSS in a 14-year-old Vietnamese-Canadian girl who presented with pulmonary symptoms, radiologic changes, and biopsy confirmation of lymphocytic interstitial pneumonia. Her dizygotic twin sister has primary SS without extraglandular manifestations. To our knowledge this is the first report of pediatric pSS with lymphocytic interstitial pneumonia and multiple pulmonary nodules on chest radiograph. We review the literature on pulmonary involvement and familial cases of pSS in childhood.