[Prevalence of antibodies against hepatitis C virus in rheumatoid arthritis. Study using second-generation tests]. / Prevalenza degli anticorpi anti-virus C dell'epatite nell'artrite reumatoide. Studio mediante i test di seconda generazione.

In order to evaluate the seroprevalence of anti-hepatitis C virus (HCV) antibody in rheumatoid arthritis (RA), where a high prevalence of false-positive anti-HCV reactions is reported, we studied 79 patients affected with RA. In these subjects we recorded some clinical and anamnestic data (history of blood transfusion, risk factors of liver disease, therapy) and determined, besides a few routine laboratory parameters including rheumatoid factor (RF), AST and ALT, the anti-HCV serology using the 1st (EIA, Ortho and Abbott; Neutralization test, Abbott; RIBA, Chiron-Ortho) and the 2nd generation tests (EIA, Ortho; RIBA, Chiron-Ortho). Four patients (of whom three were RF seronegative) were anti-HCV reactive by the 1st generation EIA tests (5.1%). According to the results of the confirmatory tests, and particularly of the 2nd generation, two patients resulted infected by HCV. These results do not confirm the previously reported high prevalence of false-positive anti-HCV reactions in RA, and demonstrated the usefulness of the 2nd generation tests in diagnosing the HCV infection.

Serum IgA and gold toxicity in rheumatoid arthritis: lack of predicting value.

The previously reported predictive value of serum IgA for gold toxicity was investigated by measuring such immunoglobulins in 114 patients affected with rheumatoid arthritis and treated with gold salts over a period of 36 months. Side effects were observed in 41 cases (35.9%) (toxic group), mostly within the first year of treatment. Basal levels of IgA were normal in all but 2 patients who maintained low levels throughout the follow-up but did not show any toxic effects. Before therapy and during gold salt administration no difference in serum IgA was noted between the toxic and the non-toxic group. After 6 months of therapy a significant decrease (p less than 0.05) in serum IgA (although never below normal limits) was detected in the toxic group as compared to both the basal values of the same group and the values of the non-toxic group at the same control. Moreover, we did not find any difference in serum IgA between toxic patients with and without mucocutaneous reactions. In our experience the monitoring of serum IgA is not useful in predicting gold toxicity.

[Assay of rheumatoid factors by the indirect immunofluorescence method]. / Determinazione dei fattori reumatoidi con il metodo della immunofluorescenza indiretta.

Sera from 69 patients affected with rheumatoid arthritis were examined for IgM, IgG and IgA rheumatoid factors (RF) by a indirect immunofluorescence method. The results were compared with those obtained from the classical rheumatoid factor latex test. By this technique we have demonstrated antigammaglobulin activity in a high proportion (23%) of sera from latex test seronegative rheumatoid patients. Moreover, by fractionated antisera it was possible to detect also IgG and IgA factors. Indirect immunofluorescence results to be a simple and available technique for detection of RF, also in many "seronegative" patients.

[Effect of D-penicillamine on serum immunoglobulins in rheumatoid arthritis]. / Effetto della D-penicillamina sulle immunoglobuline sieriche nell'artrite reumatoide.

Immunoglobulins (IgG, IgA, IgM) have been measured by radial immunodiffusion method in 43 patients affected with rheumatoid arthritis and treated with d-penicillamine (Pen). Erythrocyte sedimentation rate (ESR), serum alpha 2 and gamma globulins have alos been determined. Serum samples were collected before therapy and after 3 months (43 cases), 6 months (30 cases), 9 months (20 cases), and 12 months (15 cases, respectively). Pen was administered starting from 150 mg/day up to 600-750 mg/day. IgG did not show any significant change, whereas IgA significantly decreased only at 6 month and IgM at every follow-up. During therapy, a decrease in ESR was observed in all determinations, while alpha 2 and gamma globulins showed a reduction at 9 and 12 month follow-up. In rheumatoid arthritis Pen seems to reduce IgM and partially IgA, along with some inflammatory indices. Thus, an inhibitory effect of Pen on immunological reactions is suggested, although a direct breakdown activity on immunoglobulins cannot be excluded.