The relevance of HLA-B*5801 pharmacogenotyping in personalising allopurinol therapy / Norleen Mohamed Ali

Allopurinol is one of the drug reported to cause cutaneous ADR. From previous studies, Allopurinol causing SCAR was strongly associated with HLA-B*58:01 in Han Chinese population. The allele was present in all patients with allopurinol induced SCAR (51 out 51) but only 15% (20 of 135) in allopurinol tolerant patient and 20% (19 out 93) in the general population. The odds ratio (OR) to a patient with allopurinol induced SCAR was significantly high, 580.0 with a p value of 4.7x10'24 (Hung et al, 2005). This association was also observed in Thai population (Tassaneeyakul et al, 2009) and Korean population ( Kang et al, 2011). This study to determine the association between HLA-B*58:01 and clinical association of Allopurinol induced cutaneous adverse drug reaction in Malaysian population. As a conclusion, AS-PCR for the simultaneous detection of HLAB* 5 8:01 allele was successfully developed. This method provided a more rapid and convenient way in detection of single nucleotide polymorphism. We also have successfully genotyped our patients. The interesting finding in this study would be able to provide a preliminary data of HLA-B*58:01 allele and genotype in patients who experienced SCAR after allopurinol initiation. Based on the results, HLAB*58:01 allele is significantly associated with the increased risk of SCAR in patients using allopurinol. Therefore, this study recommended the pharmacogenetic test of HLA-B*58:01 may provide personalized medicine in clinical application and a valid marker to prevent allopurinol induced serious cutaneous reactions.