Elevation of cerebrospinal fluid sialic acid concentration in children with central nervous system leukemia.

We studied sialic acid in the cerebrospinal fluid (CSF) of 52 children with leukemia and 51 children with non-leukemic diseases. The CSF sialic acid concentration in the children with central nervous system (CNS) leukemia was significantly higher than that in the children with acute lymphoblastic leukemia without CNS involvement, acute non-lymphocytic leukemia without CNS involvement, non-hemopoietic diseases, non-suppurative meningitis, epilepsy, and other neurologic diseases. Serial determinations revealed a rapid decline in the CSF sialic acid concentrations in the patients with CNS leukemia who responded well to the therapy and who were free from relapse of CNS leukemia. The simultaneously determined CSF beta 2 microglobulin concentration did not show any significant changes. These results suggest that the CSF sialic acid may be a good indicator of CNS leukemia.