Incidence of primary Sjogren's syndrome in Slovenia.

OBJECTIVE: To determine the annual incidence of primary Sjögren's syndrome (pSS) in Slovenia. METHODS: All patients admitted to our department of rheumatology or referred to our outpatient clinic between 1 January 2000 and 31 December 2002 owing to sicca symptoms or because of a suspicion of SS were examined. Our rheumatological department is the only tertiary referral centre for the Ljubljana region, which has a population of 599 895 Caucasian people. All patients were evaluated by the validated European criteria for SS. The exact 95% confidence interval (CI) based on binomial distribution was created for the incidence estimate. RESULTS: 248 patients were examined; 71 of them (28.6%; 65 women, 6 men) were diagnosed as having pSS. Their mean (SD) age was 51.3 (14.5) years (range 19-78). The average annual incidence for pSS in our study population was calculated as 3.9 cases per 100 000 inhabitants (95% CI 1.1 to 10.2). CONCLUSION: The estimated annual incidence of pSS in Slovenia is 3.9/100 000.

Immunoserological aspects of idiopathic inflammatory muscle disease.

In the present study, the autoantibody profile of 31 Slovenian patients with idiopathic inflammatory muscle disease was estimated: 11 with polymyositis, 11 with dermatomyositis--both groups diagnosed according to the criteria of Bohan and Peter--and 9 with myositis-overlap syndromes. Autoantibodies against most relevant muscle specific (Jo-1, Mi-2) and non-specific antigens (PM-Scl, U1RNP, native Ro, Ro60, Ro52, and La) were detected with one or more detection techniques: counter-immunoelectrophoresis, enzyme-linked immunoassay, immunoblot and immunoprecipitation, each using different antigen preparations (native, recombinant). With counter-immunoelectrophoresis using a native antigen substrate (rabbit thymus extract), we were able to detect anti-PM-Scl antibodies more readily than with other techniques, probably due to conformational epitopes of native PM-Scl. Patients with this serological profile constituted a distinct group, sharing features of polymyositis and systemic sclerosis. Compared to previously reported data, the greater frequency of anti-Jo-1 found in all groups of patients (64-87% for PM, 18-20% for dermatomyositis and 33-44% for overlap syndromes) was probably due to the various methods used and the different clinical characteristics of patients. The greater prevalence of anti-Mi-2 antibodies in dermatomyositis patients (67%) and in particular in polymyositis patients (33%) and myositis-overlap syndromes (33%) seemed to be mainly due to methodological differences. A strikingly high prevalence of anti-Ro52 positive patients with polymyositis (55%), dermatomyositis (22%), and myositis-overlap syndromes (33%) was demonstrated, but was detected by only one technique. Moreover, concurrence with anti-Jo-1 antibodies was noted (69%).