Extremely low dose of 6-mercaptopurine in a Chinese child with acute lymphoblastic leukaemia and multiple pharmacogenetic mutations.

WHAT IS KNOWN AND

OBJECTIVES

Thiopurines are cornerstone drugs in the treatment of acute lymphoblastic leukaemia (ALL), but their use can be complicated by the incidence of life-threatening leucopenia.

CASE DESCRIPTION: We describe a case of a 6-year-old Chinese boy with B-ALL receiving extremely low dose of 6-mercaptopurine (only 4% of recommended dose) during the ALL maintenance therapy phase.

WHAT IS NEW AND

CONCLUSION

Complex pharmacogenetic tests and TDM should be recommended in children with complicated ALL to highlight the large individual variability in the responses to 6-MP exposure and the associated adverse effects.