4-Aminoimidazole-5-carboxamide excretion in acute leukemia

The urinary excretion of 4-aminimidazole-5-carboxamide (AIC) as been reported to be increased in children with acute leukemia and has been correlated with disease status. Using a modification of the method of Skibba et al [5], determinations were made on urine from 26 children with acute leukemia. The urine from ten normal children served as controls. The effect of chemotherapy on urinary AIC was studied comparing patients on vincristine and prednisone (V+P) with those on 6-mercaptopurine, methotrexate, and cyclophosphamide (Triple Rx). Patients in remission on Triple Rx had lower levels of urinary AIC than did patients on Triple Rx in relapse or patients on V+P in either remission or relapse. Twenty patients had sequential measurements. Values for individual patients were not predictive of disease status. One such patient is described. This study demonstrates that chemotherapy, as well as disease status, affects the urinary excretion of AIC in children with acute leukemia.