Carbamazepine and phenytoin induced Stevens-Johnson syndrome is associated with HLA-B*1502 allele in Thai population.
OBJECTIVE
Previous studies found a strong association between HLA-B*1502 and carbamazepine (CBZ)-induced Stevens-Johnson syndrome (SJS) in Han Chinese, but not in Caucasian populations. Even in Han Chinese, the HLA-B*1502 was not associated with CBZ-induced maculopapular eruptions (MPE). This study seeks to identify whether HLA-B*1502 is associated with CBZ- or phenytoin (PHT)-induced SJS or MPE in a Thai population.


METHODS
Eighty-one Thai epileptic patients between 1994 and 2007 from the Chulalongkorn Comprehensive Epilepsy Program were recruited. Thirty-one subjects had antiepileptic drug (AED)-induced SJS or MPE (6 CBZ-SJS, 4 PHT-SJS, 9 CBZ-MPE, 12 PHT-MPE), and 50 were AED-tolerant controls.


RESULTS
For the first time, a strong association between HLA-B*1502 and PHT-induced SJS was found (p = 0.005). A strong association was also found between the HLA-B*1502 and CBZ-induced SJS (p = 0.0005), making Thai the first non-Chinese population demonstrating such an association. Some patients, who were HLA-B*1502 and suffered from CBZ-induced SJS, could be tolerant to PHT and vice versa. This suggests that HLA-B*1502 may be a common attribute required for a Thai patient to develop SJS from these two AEDs; other different elements, however, are also needed for each AED. In addition, no association between HLA-B alleles and CBZ- or PHT-induced MPE was found.


CONCLUSIONS
CBZ- and PHT-induced SJS, but not MPE, is associated with HLA-B*1502 allele in Thai population.
Locharernkul
Chaichon
C
Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Loplumlert
Jakrin
J
Limotai
Chusak
C
Korkij
Wiwat
W
Desudchit
Tayard
T
Tongkobpetch
Siraprapa
S
Kangwanshiratada
Oratai
O
Hirankarn
Nattiya
N
Suphapeetiporn
Kanya
K
Shotelersuk
Vorasuk
V
D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000009:adverse effects*; D002220:Carbamazepine / Q000009:adverse effects*; D002648:Child; D004827:Epilepsy / Q000188:drug therapy / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease / Q000208:ethnology; D015235:HLA-B Antigens / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010597:Pharmacogenetics; D010672:Phenytoin / Q000009:adverse effects*; D012189:Retrospective Studies; D013262:Stevens-Johnson Syndrome / Q000139:chemically induced* / Q000235:genetics*; D013785:Thailand / Q000208:ethnology; D055815:Young Adult
D000927:Anticonvulsants; D015235:HLA-B Antigens; D002220:Carbamazepine; D010672:Phenytoin