We describe the first case, to our knowledge, of usual interstitial pn
eumonia (UIP) as the pulmonary manifestation in primary Sjogren's synd
rome (SjS). A 45-year-old woman was admitted to our hospital because o
f a dry cough and an interstitial shadow on a chest roentgenogram. Lab
ial biopsy and sialogram confirmed a diagnosis of SjS. BAL fluid analy
sis revealed lymphocytosis with a decreased CD4/CD8 ratio compatible w
ith bronchiolitis obliterans organizing pneumonia or lymphoid intersti
tial pneumonia. Open-lung biopsy specimen, however, showed evidence of
UIP. Open-lung biopsy was a useful and necessary examination to deter
mine the nature of the pulmonary complication in primary SjS. Conserva
tive treatment without corticosteroids maintained a stable condition f
or a follow-up period of 3 years.