No acute varicella-zoster virus replication in peripheral blood mononuclear cells during postherpetic neuralgia

Patients suffering from postherpetic neuralgia (PHN) were investigated whether varicella-zoster virus (VZV) DNA or RNA could be detected in their peripheral blood mononuclear cells (PBMCs). Altogether 16 samples were tested by standard polymerase chain reaction (PCR) for open reading frame (ORF) 14 and ORF 29, standard and nested PCR for ORF 63, and isothermal transcription-based nucleic acid amplification (NASBA) for ORF 63 and ORF 68. By these methods neither VZV DNA nor VZV RNA could be detected. The obtained results are in contrast to those of other authors (Vafai et al., 1988; Mahalingam et al., 1995) but support the hypothesis of Bennett (1994) and Kost and Straus (1996) proposing that PHN is not caused by acute VZV replication but a consequence of neuronal damage accompanying replication of VZV in ganglia during zoster episodes.