Sj?ren's syndrome with infiltrative lung disease showing upper lung field predominance]

We report two cases of Sj?ren's syndrome (SjS) with infiltrative lung disease showing upper lung field predominance. Case 1 was seen in a 68-year-old woman, who was admitted with dyspnea on exercise. Chest CT scanning demonstrated a central predominance of irregularly shaped consolidation with tractionectasis, distributed along the broncho-vascular bundles in both upper lobes. Case 2 occurred in a 70-year-old woman, who was admitted with cough. Chest CT scan showed a central predominance of irregularly shaped opacities with multiple small cystic structures in both upper lobes. Both cases were shown to be nonspecific interstitial pneumonia (NSIP) by video-assisted thoracoscopic lung biopsy, in which lung involvements were distributed around the bronchovascular sheath with relative sparing of the subpleural region. Although neither case complained of sicca symptoms, decreased saliva production was detected using the Saxon test, and further examinations revealed the presence of primary SjS. Pulmonary involvement in SjS is variable, and distribution along the broncho-bronchioles in the majority of the upper central lung field is a characteristic appearance of SjS lung disease. In patients with such patterns in chest radiography, further diagnostic differentiation should be conducted to confirm or rule out SjS.