HYPEREOSINOPHILIC VARIANT OF PH'-POSITIVE CHRONIC MYELOID-LEUKEMIA

Aim. To confirm clonal nature of idiopathic hypereosinophilic syndrome (IHES), its relevance to Ph-'positive chronic myeloid leukemia. Mater ials and methods. 3 cases of isiopathic hypereosinophilic syndrome are reported with morphologic analysis of bone marrow cells and cytogenet ic examinations. In one patient the presence of Ph'-chromosome was con firmed at fluorescent in situ hybridization (FISH) and molecular-genet ic analysis (bcr/abl). Samples of bone marrow, spleen and liver were e xamined pathohistologically. Results. The presence of chromosome anoma ly t(9;22), i.e. Ph'-chromosome, associated with chronic myeloid leuke mia (CML) was identified in all the 3 cases. There was also myeloid hy perplasia in the bone marrow (with primarily mature, eosinophilic gran ulocytes), spleen and liver, depression of megakaryocyto- and erythrop oiesis. 2 patients had similar clinical symptoms which was not typical for CML in chronic phase: fever elevated ESR, clear-cut anemia and th rombocytopenia. In the absence of hyperleukocytosis, blood and bone ma rrow eosinophils remained high (42.5, 21.5, 42.5% and 21.4 7.1, 6.5%, respectively) due to 'mature'' forms. The number of blasts in the bone marrow was maximum 2.4%. Conclusion. The literature and the obtained data suggest closeness of idiopathic hypereosinophilic syndrome and Ph '-positive CML within myeloproliferative diseases.