Chemical analysis of parotid saliva and lacrimal fluid in psoriatics.

A total of 28 psoriatics and the same number of healthy individuals as controls were subjected to chemical analyses of their lacrimal fluid and parotid saliva to assess whether any functional disturbances attributable to psoriasis were detectable, i.e. if they have sicca syndrome (SS) or not. The stimulated parotid flow rate and Schirmer test I proved to be normal in both series. A significant elevation of salivary IgA, alpha-amylase, and Na+ was found in psoriatics when compared with the controls. On the other hand, salivary lysozyme values in psoriatics were markedly lowered. There was a distinct interrelationship between salivary IgA, beta 2-microglobulin, and lysozyme detectable in both series. The findings are discussed in terms of the increased immunological activity in psoriasis, and the possible role of cAMP and neural regulation in the causation of elevated amylase and Na+ levels in psoriatics is hypothesized. These alterations in salivary constituents might provide a protective system for oral mucous membranes against this skin disease.