Objective: In some herpes zoster (HZ) patients, one symptom is problematic; postherpetic neuralgia (PHN), a persistence of pain such as spontaneous pain and stimulus-evoked pain, allodynia or hyperpathia, for more than 6 months after healing of the vesicular eruptions. In our previous study, we reported the association between HLA alleles, HLA-A*33 and B*44, and PHN patients. In this study, we aim to refine the association of these alleles with PHN or HZ using higher-resolution HLA typing technique with an increased sample size.
Methods: HLA allele frequencies were compared in 70 PHN patients, 80 HZ patients, 52 HZ(-) patients, and 140 Japanese controls using HLA typing kits of SSOP protocols.
Result and conclusion: The allele frequencies of HLA-A*3303, B*4403, and DRB1*1302 in PHN(+) patients were significantly higher than those in Japanese controls (P=0.00007, P=0.000002, and P=0.0003, respectively). The frequencies of above alleles in PHN(+) patients were also significantly higher than those in PHN(-) patients (P=0.03, P=0.006 and P=0.03, respectively). However, no association was found in comparison of HZ(+) patients and HZ(-). And the frequency of HLA-B*5101 in HZ(-) patients was significantly higher than those in HZ(+) and PHN(+) patients (P=0.003 and P=0.009, respectively) indicating that HLA-B*5101 functions as a protective allele to HZ.