Diagnostic and prognostic value of quantitative immunohistological examination of lip biopsy in Sjögren's syndrome.

Three patients are presented to illustrate the diagnostic and prognostic value of quantitative immunohistological examination of labial salivary gland biopsy in Sjögren's syndrome. In an obvious case of primary Sjögren's syndrome and in a case of rheumatoid arthritis without clinical and serological evidence of secondary Sjögren's syndrome, quantitative immunohistological examination of the labial salivary gland biopsy gave more appropriate information than the widely accepted lymphocytic focus score criterion for Sjögren's syndrome. In the third case quantitative immunohistological examination disclosed monoclonal B-cell expansion in the labial salivary gland biopsy six months before evidence of systemic monoclonal gammopathy appeared.