Adult primary IgA nephropathy and common viral infections

Serum samples obtained from 69 histopathologically proven IgA nephropathy (IgAN) patients and 563 healthy controls were examined to evaluate the association between IgAN and common viral infections. Antibody titres to cytomegalovirus (CMV), herpes simplex virus (HSV), Varicella-Zoster virus (VZV), Influenza A (Inf. A) and Influenza B (Inf. B) viruses were determined, using a complement fixation test. The viral antibody titres were considered to be positive with dilutions of 1:8 or greater except for Epstein-Barr virus (EBV), studied using immunofluorescence, which was considered to be positive with dilutions of 1:10 or greater. The positive rate of Inf. B antibody in IgAN patients was significantly lower than that in controls. The frequency of positive CMV antibody titres was higher than for controls, but with only borderline statistical significance (P = 0.050). The frequency of positive CMV and Inf. B titres was compared by age in IgAN patients and controls, but showed no statistically significant difference. Comparisons of percentage distributions at each antibody dilution level to the common virus of IgAN patients and controls were made; however, none showed a statistically significant difference. In conclusion, no absolutely higher frequency of positive antibody titres for common viruses was demonstrated in IgAN patients in this study.