Rapid diagnosis of primary varicella infection by the detection of Varicella-Zoster Virus (VZV)-specific T-cells before seroconversion

BAIKER, A.; HAASE, R.; VIZOSO PINTO, M. G.; PFREPPER, K-I.; PETRICH, A.; DEML, L.; NITSCHKO, H.; JAEGER, G.

Cernobbio, Como lake, Italy

Congreso; Fourth European Congress of Virology; 2010

Background: Rapid Vricella-Zoster Virus (VZV) identification techniques are indicated for caseswith severe or unusual varicella to initiate specific antiviral therapy. Methods: Analysis of VZV-specific T-cells wasperformed by a novel in house test assayed by flow cytometry after intracellular INF gamma , staining of isolatedand ex vivo stimulated peripheral blood mononuclear cells. Results: We report the case of a 54-year-old Germanman who presented with skin rash and fever (day 0 ). Serological analysis of blood taken at the day of rash onsetexhibited no Varicella-Zoster Virus (VZV)- specific antibody titers indicative for a past (VZV-IgGnegative) or primary(VZV-IgMnegative) VZV infection. In order to confirm the suspicion of primary varicella, a second blood sample wastaken at day 2 post rash onset. But again, subsequent serological testings for VZV-specific IgG and IgM antibodytiters exhibited negative results. However, abundant numbers of VZV-specific CD4+ T-cells could be detected withinthis second sample. Detected VZV-specific CD4+ cell titers yielded 1 % when VZV lysate was used for stimulation,and 0,73 % when utilizing recombinant glycoprotein E (gE). A third blood sample was taken at day 6 post rashonset. The respective VZV serology demonstrated seroconversion (VZV-IgG and VZV-IgM positive). VZV-specificCD4+ T-cells titers decreased to 0,19 % when stimulating with VZV lysate, and 0,17 % when stimulating withrecombinant gE. Conclusions: Here we show that the diagnosis of early varicella infection is possible before theonset of seroconversion by detection of VZV-specific T-cells.