Recurrent central nervous system acute lymphoblastic leukemia associated with cerebrospinal fluid eosinophilia and basophilia: a proposed cytokine-mediated mechanism.

The authors describe a case of acute lymphoblastic leukemia with two subsequent isolated central nervous system (CNS) relapses, each accompanied by cerebrospinal fluid (CSF) eosinophilia and basophilia. Despite marked peripheral blood and bone marrow eosinophilia at initial diagnosis, the patient had no blood or bone marrow eosinophilia, basophilia, or leukemic blasts at the time of either CNS relapse. The literature is reviewed and a possible cytokine-based mechanism is proposed for the unusual finding of simultaneous CSF eosinophilia, basophilia, and leukemic blasts.