The human histocompatibility leukocyte antigen (HLA) haplotype is associated with the onset of postherpetic neuralgia after herpes zoster.

In some herpes zoster patients, pain persists for more than 3 months or more after healing of vesicular eruptions; this condition is termed postherpetic neuralgia (PHN). We have recently reported the association of the human histocompatibility leukocyte antigens (HLA) haplotype, HLA-A*3303-B*4403-DRB1*1302 with PHN patients; however, it has not been determined whether the haplotype is also associated with herpes zoster that did not develop subsequent PHN. To distinguish whether the haplotype is associated with herpes zoster or the development of PHN, we examined if herpes zoster patients without subsequently PHN are also associated with the HLA haplotype or not. Herpes zoster patients were followed up for more than 6 months, and HLA alleles and haplotypes were compared among the PHN patients (n = 52) the herpes zoster patients who did not develop PHN (n = 42) and healthy controls (n = 125). The frequencies of the risk haplotype in the PHN patients, in the healthy controls and in the herpes zoster patients without subsequent PHN were 16.3, 5.2 and 4.8%, respectively. While the frequency of the risk haplotype was significantly higher in the PHN patients than in the healthy controls (P = 0.0006) no difference was observed between the herpes zoster patients without subsequent PHN and the healthy controls. No significant association was found between the duration of symptoms or the site of herpes zoster and the HLA alleles and the haplotype. These results suggest that the HLA-A*3303-B*4403-DRB1*1302 haplotype plays an important role in the development of PHN after herpes zoster, but not in the onset of herpes zoster.