Objective.To assess the possible association between the PTPN22 gene 1858C3 T polymorphism and the predisposition and clinical expression of 2 systemic autoimmune diseases, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE).Methods. Our study population consisted of 826 RA patients, 338 SLE patients, and 1,036 healthy subjects. All subjects were of Spanish Caucasian origin. Genotyping of the PTPN22 gene 1858C3 T polymorphism was performed by real-time polymerase chain reaction technology, using the TaqMan 5-allele discrimination assay.Results. The overall distribution of genotypes in the RA patients was significantly different from that in the controls (P ‫؍‬ 0.005, by chi-square test with 2 ؋ 3 contingency tables). We observed a statistically significant difference in the distribution of the PTPN22 1858T allele between healthy subjects (7.4%), and RA patients Conclusion. These results suggest that the PTPN22 1858T allele may confer differential susceptibility to RA and SLE in the Spanish population.

We conducted the current study to characterize the clinical presentation of primary Sjögren syndrome (SS) in a large cohort of Spanish patients and to determine whether epidemiologic, clinical, and analytical features modulate disease expression. Patients were from the GEMESS Study group, which was formed in 2005 and included 12 Spanish reference centers. By March 2007, the database included 1010 consecutive patients, recruited since 1994, both incident and prevalent cases. The cohort included 937 women and 73 men (ratio, 13:1), with a mean age of 53 years at diagnosis and 59 years at inclusion in the registry. Multivariate analysis showed that male patients had a lower frequency of thyroiditis, Raynaud phenomenon, and antinuclear antibodies. Young-onset patients had a low degree of sicca involvement (xerostomia and parotid enlargement) and a high frequency of immunologic markers (anti-Ro/SS-A and low C4 levels). Patients with disease duration of more than 10 years had a higher prevalence of xerophthalmia, parotid enlargement, lung involvement, and peripheral neuropathy in comparison with incident cases. The subset of patients with anti-Ro/La antibodies had the highest prevalence of most systemic, hematologic, and immunologic alterations (higher frequency of Raynaud phenomenon, altered parotid scintigraphy, positive salivary gland biopsy, peripheral neuropathy, thrombocytopenia, and rheumatoid factor). Hypocomplementemia was associated with a higher frequency of vasculitis and lymphoma, and cryoglobulins with a higher frequency of parotid enlargement, vasculitis, and leukopenia.Epidemiologic, clinical, and analytical features have a significant impact on the clinical presentation of primary SS, influencing the results of the main diagnostic tests, the prevalence and diversity of extraglandular involvement, and the frequency of the main immunologic markers. Primary SS should be considered as a systemic autoimmune disease that can express in many guises beyond sicca involvement.