Relationshipp of HLA-Dw3 and HLA-B8 to Sjögren's syndrome.

Nineteen patients with Sjögren's syndrome were evaluated for the presence of HLA-B8 and HLA-Dw3. HLA-B8 was found in 57.8% of patients and 20.1% of 96 controls (P less than 0.001). HLA-Dw3 was detected in 73.7% of the patients and 24.0% of controls (P less than 0.0001). Statistical evaluation of the association of both antigens with Sjögren's syndrome revealed that the primary association was with HLA-Dw3 (P less than 0.005). Patients with HLA-Dw3 had a lower mean parotid salivary flow rate (0.8 +/- 0.3 ml/10 minutes/gland versus 5.6 +/- 1.2 ml/10 minutes/gland, P less than 0.0004) and a more intense lymphocytic infiltration into labial salivary glands (focus score 7.2 +/- 0.9 versus 3.4 +/- 0.9, P less than 0.04) than did patients without HLA-Dw3. The difference in the intensity of the lymphocytic infiltration was even more significant when patients with both HLA-Dw3 and HLA-B8 were compared with patients with neither antigen (focus score 7.5 +/- 1.0 versus 2.8 +/- 0.8, P less than 0.02). In addition, all patients with severe keratoconjunctivitis sicca had both antigens. Our observations suggest that a number of genes may interact to determine susceptibility and severity in Sjögren's syndrome.