EBV and CMV viral load in rheumatoid arthritis and their role in associated Sjögren's syndrome.

INTRODUCTION: The role of viral infections in the pathogenesis of autoimmune diseases has long been suggested, but little evidence is available. OBJECTIVE: This study aimed to evaluate an association between EBV and CMV and the presence of rheumatoid arthritis and its association with Sjögren's Syndrome. PATIENTS AND METHOD: A case-control study was performed with 227 patients divided in RA (n = 99), RA/SS (n = 20), and C (n = 128). Resting salivary flow rate and Schirmer's test were performed; minor salivary gland biopsy was indicated in the case of suspected Sjögren's syndrome. CMV and EBV viral loads were quantified in peripheral blood, and their presence in glandular tissue samples was evaluated by in situ hybridization (EBV) and immunohistochemistry (CMV). RESULTS: EBV was more frequent in RA and RA/SS than in C (P < .000007). No correlation with clinical markers (P > .05) or between RA and RA/SS was found (P > .05). A higher number of EBV/DNA copies were found in RA (158.52 copies/µL) and RA/SS (99.24 copies/µL) (P = .739). EBV/DNA was associated with the Schirmer test (P = .0231). CMV was detected in one patient of the RA group. None of the viruses were detected in biopsies of minor salivary glands. CONCLUSIONS: Detection of EBV/DNA in peripheral blood was associated with RA regardless of the presence of SS.

Effect of Xerostomia on the Functional Capacity of Subjects with Rheumatoid Arthritis.

OBJECTIVE: To evaluate the intensity of xerostomia and hyposalivation in subjects with rheumatoid arthritis (RA) as well as the effects of these conditions on functional incapacity and disease activity. METHODS: The study sample comprised 236 individuals of both sexes who had RA. All the individuals were submitted to clinical evaluation and unstimulated sialometry. Functional capacity was determined by using the Health Assessment Questionnaire (HAQ), xerostomia was assessed using the Xerostomia Inventory, and disease activity was evaluated with the 28-joint Disease Activity Score (DAS28). The effect of Sjögren syndrome (SS) was analyzed, and the sample was divided into 2 groups: RA (191 subjects) and RA/SS (45 subjects). RESULTS: The Xerostomia Inventory showed positive and significant correlation with fatigue (r = 0.243; p < 0.0001), number of painful joints (r = 0.218; p = 0.001), HAQ (r = 0.279; p < 0.0001), and DAS28 (r = 0.156; p < 0.0001). On regression analysis, both xerostomia (OR 3.89, 95% CI 1.84-8.23, p < 0.001) and DAS28 (for severe disease activity: OR 13.26, 95% CI 3.15-55.79, p < 0.001) showed influence on functional incapacity. Forty-five individuals (19.1%) presented with secondary SS, and having this diagnosis was not associated with disease activity or functional capacity. CONCLUSION: Xerostomia demonstrated an adverse effect on quality of life of subjects with RA, being associated with a reduction in functional capacity. In this clinical setting, xerostomia can be monitored as a marker of worse clinical evolution.