Human herpesvirus-6 genomes in histiocytic necrotizing lymphadenitis (Kikuchi's disease) and other forms of lymphadenitis.

The cervical lymph nodes of 27 patients with histiocytic necrotizing lymphadenitis (HNL) were examined, as were those of 9 patients with tuberculous lymphadenitis (Tb), 10 with reactive paracortical hyperplasia (RPH), and 10 with nonspecific lymphadenitis (NSL). Southern blot analysis, the polymerase chain reaction (PCR), and in situ hybridization were use to locate the human herpesvirus-6 (HHV-6) genome. Southern blot analysis showed that all cases were negative for HHV-6 genomes, although all but one HNL case expressed HHV-6 genome using PCR. On in situ hybridization all 10 HNL cases, 6 of the 10 RPH cases, 6 of the 10 NSL cases, and 2 of the 9 Tb cases showed HHV-6 DNA. These results indicate that the presence of HHV-6 genome is not specifically related to HNL, and that this virus could hibernate in a latent form in the cervical lymph nodes. In addition, we examined three different primers (A, B, and C) for PCR amplification of HHV-6 genomes.