Serum beta-2-microglobulin in Sjögren's syndrome.

The serum concentration of beta-2-microglobulin was determined with a radioimmunoassay in 52 patients with keratoconjunctivitis sicca, 29 of whom had Sjögren's syndrone. Eleven (38%) of the patients with Sjögren's syndrome had high serum values. These cases had a higher mean age and a higher frequency of the complete triad of Sjögren's and of antinuclear antibodies than had the lower value cases. The sicca components per se did not seem to influence the serum concentration of beta-2-microglobulin. Most of the few complications occurred in patients with high values.