Acute lymphoblastic leukemia with eosinophilia and basophilia.

A boy with acute lymphoblastic leukemia showed cerebrospinal fluid and blood eosinophilia and basophilia. No cause for the eosinophilia or basophilia was identified, but they preceded the appearance of leukemic lymphoblasts in both CSF and blood. The first appearance of basophils and eosinophils in the CSF was associated with acute symptomatology and responded completely to antileukemic therapy. Though treatment with intrathecal drugs reversed major neurological signs, there was evidence of generalized cerebral cortical atrophy. The possible mechanisms responsible for this unusual cellular reaction include: 1) reaction to antileukemic therapy; 2) immunological reaction to the lymphoblasts; 3) ectopic hormone production; 4) common stem cell origin of lymphoblasts, basophils, and eosinophils. The last explanation seems the most likely.