hello! first i would like to advice you to stick to the treatment your child is getting for leukemia
and u should have faith in your doctor. leukemia is treated in different phases u might me knowing by now. every chemotherapy
drug has got its side effects, and every the investigations are planned on protocol basis to know of any side effects at the earliest. the doses of the drugs need to be modified as per the investigations and even may be stopped for awhile or withdrawn is need arises. i can understand the agony u must be going through seeing all this but these things are done only for the safety of your child. and as far as the levels of AST and ALT
are considered the does are modified generally when they reach twice the normal value. so please be patient and co-operate with your doctor.