[Comparative evaluation of effectiveness of traditional serologic and modified methods of herpes zoster laboratory diagnostics].

Aim: Comparative evaluation of effectiveness of traditional serologic and modified diagnostic methods of disease arising due to varicella and herpes zoster virus (VZV) reactivation.

Materials And Methods: 2 groups of patients were examined. The main group consisted of 39 patients with manifest form of herpes zoster (HZ), control--20 healthy donors. Sex composition of the groups did not differ. Traditional method of serologic diagnostics included determination of anti-gE VZV IgG and anti-VZV IgG and anti-IgM in patient and donor blood sera by using EIA. Modified methods consisted of isolation in density gradient and cultivation for 48 hours of peripheral blood mononuclears (PBMC) in RPMI-1640 complete culture medium containing 10% of fetal bovine serum, 4 mM L-glutamin and gentamycin. Concentrations ofanti-VZV IgG and IgM were then determined in culture medium by using EIA.

Results: In all the examined HZ patients and healthy donors anti-VZV IgG were detected in blood. Only in 26 (67%) of 39 HZ patients anti-gE VZV IgG and anti-VZV IgM were determined in blood sera. Among donors false positive results for these markers were detected in 10% and 5% of cases, respectively. During simultaneous determination of anti-gE VZV IgG and anti-VZV IgM the specificity of the method increased to 100%, sensitivity of the diagnostic method based on simultaneous determination of anti-gE VZV IgG and anti-VZV IgM was 59%. During analysis of spontaneous production of anti-VZV antibodies by PBMC in 38 (97.4%) of 39 patients anti-VZV IgG were determined in PBMC culture, anti-VZV IgM production was observed only in 4 patients. In control group false positive results of anti-VZV IgG and IgM production by PBMC was not detected by the modified method (100% specificity). At equal specificity level sensitivity of the modified method based on determination of spontaneous anti-VZV IgG production by PBMC culture was significantly higher than effectiveness of the traditional serologic diagnostics (97.4% and 59%, p < 0.0001).

Conclusion: The data obtained allow to recommend during diagnostics of manifest and atypical VZV infection forms arising due to endogenous virus reactivation the new modified method of laboratory diagnostics of the disease as having higher sensitivity compared with traditional serologic method.