Detection of varicella-zoster virus (VZV) DNA in throat swabs and peripheral blood mononuclear cells of immunocompromised patients with herpes zoster by polymerase chain reaction

Abstract

Background: Varicella-zoster virus (VZV) is rarely isolated from throat swabs and peripheral blood leukocytes from patients with herpes zoster by conventional virus isolation methods. The polymerase chain reaction (PCR) is a highly sensitive method to detect VZV genomes. It has been reported that VZV DNA was detected in the cerebrospinal fluid (Puchhammerstöckl et al., 1991) and peripheral blood mononuclear cells (PBMC) of patients with VZV-associated neurological symptoms (Gilden et al., 1992) by PCR. Objectives: We used the nested double PCR to detect VZV DNA in patients with herpes zoster. Study design: Sixteen patients with herpes zoster, ten immunocompromised and six immunocompetent patients, were studied. Throat swabs and PBMC were collected weekly and examined for VZV DNA by the nested double PCR. Results: VZV DNA was detected in 60% ( 6 10 ) of throat swabs and in 60% ( 6 10 ) of PBMC of immunocompromised patients, and in 16.7% ( 1 6 ) of throat swabs and in 33% ( 2 6 ) of PBMC of immunocompetent patients within two weeks after the onset of skin rash. VZV DNA was detected in throat swabs or PBMC of two patients 5 and 7 days after cessation of acyclovir. Conclusion: VZV DNA was detected in throat swabs and PBMC-associated viremia exist in patients with herpes zoster. It is suggested that VZV spread from sensory ganglia to the skin or pharyngeal area along the nerve fiber or hematogenously and local cutaneous replication of VZV can lead to viremia with subsequent hematogenous dissemination in patients with herpes zoster.