A new model for classification of disease manifestations in primary Sjogren's syndrome: Evaluation in a retrospective long-term study

Objectives. The clinical features of 80 patients with primary Sjogren's syndrome (PSS) were revised in order to evaluate the descriptive and analytical facilities of a newly proposed model for classification of the exocrine and nonexocrine disease manifestations in PSS. Design. Retrospective, long-term (median 7.5 years follow-up) observational, clinical study. Setting. Patients were recruited from our Department, which is a tertiary referral centre for PSS patients. Subjects, Eighty patients fulfilling the Copenhagen criteria for keratoconjunctivitis sicca and/or xerostomia and followed between 1972 and 1991 were studied. Results. All patients had 'surface exocrine disease' and in 31% this was the only disease manifestation, 'Internal organ exocrine disease' was found in 25% of the patients, whilst 2.5% developed 'monoclonal B lymphocyte disease' (non-Hodgkin's lymphoma), 28% displayed 'inflammatory vascular disease', 25% noninflammatory vascular disease', 41% 'mediator-induced disease' and 2.5% 'autoimmune endocrine disease' (thyroiditis). In patients with 'internal organ exocrine disease' the frequencies of 'mediator-induced disease' (70%; P < 0.01) and 'inflammatory vascular disease' (50%; P < 0.03) were significantly higher than expected by chance. The level of immunoinflammatory activity (assessed by plasma IgG, serum ANA and focus scoring of minor labial salivary gland biopsies) correlated with the extent of clinical disease as assessed by the model. Conclusions. We conclude that this theoretically based model for classification of disease manifestations in PSS contains descriptive and analytic powers which may assist the clinical handling of these patients.