Morphometric study of salivary glands in primary Sjögren's syndrome.

The relationship between structural changes of the minor salivary glands with age was evaluated by morphometric analysis in twenty patients with primary Sjögren's syndrome (prim. SS) (Group I) and in twenty sex and age-matched normal subjects (Group II). No statistically significant differences were found in the acinar tissue, intralobular ducts (ILD) and fibrous tissue between the two Groups. In contrast, there was a 5-fold increase in the volume fraction of inflammatory cells in Group 1. In both Groups the percentage of fibrous tissue and ILD increases and the percentage of acinar tissue decreases linearly with age. In Group I the increase in the volume percentage of fibrous tissue and the decrease in the volume fraction of the acinar tissue were not related to the volume percentage of inflammatory cells. These results demonstrate that in prim. SS the acinar atrophy is not related to the inflammatory process but is an age-dependent phenomenon.