Abnormal nucleotide pattern in the eosinophils of a patient with acute lymphoblastic leukemia associated with...

In this article we present a patient with acute lymphoblastic leukemia (ALL) associated with eosinophilia, in which the eosinophilia preceded a meningeal and bone-marrow relapse of ALL. We analysed the purine and pyrimidine nucleotide content of the eosinophils (92% pure) and compared the nucleotide pattern with that of eosinophils from healthy donors and from patients with eosinophilia not associated with leukemia. The ratios of purine:pyrimidine and of uracil:cytosine nucleotides were decreased compared with those in eosinophils from healthy donors and from patients with eosinophilia with other aetiologies. The total nucleotide concentration was increased, especially the concentration of UDP-sugars and pyrimidine nucleotides. The decrease in these ratios and the increase in concentration of the nucleotides and the UDP-sugars were also detected in leukemic cells of patients with ALL (de Korte et al., Leukemia Res. 10, 389-396 (1986) compared to normal lymphocytes. We suggest a malignant character of the eosinophils in our patient with ALL associated with eosinophilia, in contrast with the non-malignant state suggested previously for these cells.