BACKGROUND: Recent study demonstrated that HLA-B*1502 was a common risk allele 
in aromatic antiepileptic drugs (AEDs) induced Stevens-Johnson syndrome and 
toxic epidermal necrolysis in Han Chinese. However, the association of 
AEDs-induced mild maculopapular eruption (MPE) with HLA-B*1502 remains unclear 
until recently. In the present study, we conducted a pilot study to detect a 
possible association of oxcarbazepine (OXC)-induced MPE with HLA-B*1502 allele 
in Chinese Han population.
METHODS: We enrolled 90 subjects involving 9 patients with OXC-induced MPE and 
two groups of controls, 9 OXC-tolerant and 72 normal controls. High-resolution 
HLA genotyping was performed by specific kit. The results of HLA genotyping are 
expressed as positive or negative for HLA-B*1502 allele. Differences in genotype 
frequencies between groups were assessed by the Fisher's exact test.
RESULTS: Four cases were detected as positive for HLA-B*1502 amongst 9 patients. 
However, only 1 subject was positive amongst 9 tolerant controls, and 6 subjects 
were positive amongst 72 normal controls. The difference in HLA-B*1502 allele 
frequencies between the MPE group and normal controls was statistically 
significant (OR: 8.8; 95% CI: 1.853-41.790; P=0.011). In addition, we also 
observed an increased frequency of HLA-B*1502 allele in patients (44.44%) 
compared with tolerant controls (11.11%), although it failed to reach 
statistical significance (P=0.294).
CONCLUSIONS: Our findings indicate that HLA-B*1502 allele may contribute to the 
genetic susceptibility to OXC-induced MPE in Chinese Han population. In order to 
safer AEDs use, we recommend that HLA-B*1502 allele should be tested for 
patients with OXC-induced MPE before changing to other AEDs, and AEDs with 
similar chemical structure should be avoided in individuals who test positive 
for HLA-B*1502 allele. It should be pointed out that, however, our results may 
well be just by chance owing to the small sample size and should be further 
confirmed in future studies.