Reply to Dr. Chouchana's letter

摘要

Dear Sir,We would like to thank Dr. Chouchana for the comments on our manuscript and thereby giving us the opportunity to discuss this important topic again.The thiopurine metabolism is complex and several enzymes, besides TPMT, are probably of clinical importance. Clinicians thus need to be aware of the limitations of a TPMT test and use it in a correct clinical context.Our aim was to investigate whether TPMT genotype or phenotype was the best pre-treatment evaluation of TPMT status, since neither method is perfect. It needs to be stressed that these tests, even if used in combination, cannot replace the need for continued monitoring of full blood counts during treatment with thiopurines. Furthermore, the majority of hematological adverse events cannot be explained by the TPMT status.