BENIGN TRANSIENT HYPERPHOSPHATASEMIA IN CHILDREN WITH LEUKEMIA AND LYMPHOMA

A temporary elevation of serum alkaline phosphatase has been described in young children who have no evidence of liver or bone disease. This phenomenon has been termed benign hyperphosphatasemia of infancy. Its occurrence is described in three children undergoing chemotherapy for acute lymphoblastic leukemia and lymphoma. All three children were in remission and in the consolidation or maintenance phase of their ther apy when the hyperphosphatasemia occurred, All children were also rece iving methotrexate (IM and TV), oral 6-mercaptopurine, and oral sulfam ethoxazole/trimethoprim. Although these agents are associated with hep atotoxicity other liver transaminases (ALT, AST) remained at normal co ncentrations, and there was an elevation only in the bone isoenzyme of alkaline phosphatase, thus making hepatic toxicity an unlikely etiolo gy for the hyperphosphatasemia. No alteration in chemotherapy was nece ssary for resolution of the elevated alkaline phosphatase in these chi ldren.