To assess the prognosis of patients with sicca symptoms and to identify the clinical and immunological factors that most sensitively predict the later development of primary Sjögren's syndrome (SS) or other connective tissue diseases.
Eighty seven patients (72 female, 15 male) with sicca symptoms were re-evaluated after a median follow up time of 11 years (range 8-17). The clinical examination included ophthalmological examination (Schirmer's test, break up time and Rose-Bengal staining). Labial salivary gland biopsy was performed and histological findings graded according to the Chisholm-Mason scale. The immunoserological tests included determination of rheumatoid factor (RF), antinuclear antibodies (ANA), anti-extractable nuclear antigen-antibodies (ENA), serum immunoglobulins IgA, IgG, and IgM, and serum beta2-microglobulin (beta2m).
At follow up 31 patients (36%) fulfilled modified Californian criteria (salivary flow measurements were not performed and Chisholm-Mason grades 3-4 were regarded as diagnostic histological findings) for possible or definite SS. Likewise, a significant progression of the histological findings was observed. Labial salivary gland re-biopsy was performed in 42 patients with grade 0-2 findings at baseline, progression to grades 3-4 being observed in 21 (50%) at follow up. The patients who later developed SS were at baseline significantly older (mean (SD) 52 (9) v 44 (14) years, p</=0.005) compared with those not fulfilling the SS criteria at follow up; they also had significantly higher serum beta2m (p</=0.0005) and IgG concentrations (p</=0.005), and they had positive ANA more frequently (p</=0.01).
These results suggest that high age, increased values of serum beta2m, ANA positivity and increased concentrations of serum IgG, might be useful indicators for the subsequent development of SS in patients with sicca symptoms. The prognosis of patients with these symptoms was favourable, and the clinical course was benign even in the 36% of patients who developed SS. No cases of lymphoma were observed.