Cytochemical “normal” and “abnormal” eosinophils in acute leukemias

Abstract

Eosinophilic leukocytes may accompany a great variety of disorders and different types of acute leukemias. The most striking morphologic feature of eosinophils is their specific granules, but morphology alone often is insufficient to differentiate normal from abnormal eosinophils. Cytochemically, the eosinophils were considered "normal" when they did not contain alkaline phosphatase, chloroacetate esterase, toluidine blue metachromasia, Astra blue positivity, and specific PAS-positive granules, but did have peroxidase and cyanide-resistant peroxidase activities, Sudan black positivity and moderate naphthol-AS esterase or alpha-naphthyl esterase and acid phosphatase positivities. In seven cases of acute leukemias (two acute myeloblastic and five myelomonocytic), in contrast with their normal behaviour, the eosinophils show "abnormal" cytochemical positivities consisting of chloroesterase activity, PAS and Astra blue positivities of the specific granules, toluidine blue metachromasia, and cyanide-resistant peroxidase of a few specific granules. Cytochemical investigations may provide additional criteria for evaluating the abnormality of the eosinophilic cell in leukemias.

Myelodysplastic Syndrome Preceding Acute Myelomonocytic Leukemia with Dysplastic Marrow Eosinophilia and Inv(16)

“…Contrary to the findings in acute lymphoblastic leukemia [18], eosinophils in eo sinophilic leukemia proved to be leukemic because those cells had an abnormal karyotype [19,20]. As was shown by cytochemical reactions [21], abnormal eosinophils in M4Eo are involved in the leukemic process.…”

Eosinophil activation markers in clonal and non-clonal eosinophilia

“…Within patients with eosinophilia, the clonal eosinophilia group showed significantly higher ECP levels (median, IQR) compared to those of the non-clonal eosinophilia groups (30. 15 However, in clonal eosinophilia vs. nonclonal eosinophilia groups there were no significant differences in the median levels of IL-5 ( Figure 2). Our results are not consistent with a previous study (9), in which IL-5 levels were much higher in clonal compared to non-clonal eosinophilia.…”

“…In AML-Eo cases eosinophils major atypia consists in positivity for naphthol-AS-chloroacetate esterase (NACE). This cytochemical feature is missing in eosinophils from normal or reactive conditions and most myeloid malignancies with eosinophilia (15). We investigated 6 patients with AML -3 patients with AML-M4 (FAB) and inv(16)/ t(16;16) and 3 patients with AML-M2 (FAB) and t(8;21).…”

A Case of Acute Myelogenous Leukaemia Associated with Eosinophilia: Cytogenetic Study of Eosinophilic Colonies Showing the Origin of the Normal Clone

“…In their morphological and cytochemical studies on eosinophils in acute leukaemia, several authors have suggested the involvement of eosinophils in ma lignant clones [5,6]. The presence of Auer bodies in eosinophils [3,14] and the observation of a marker chromosome overlapping the eosinophilic granules [8] also suggest its involvement.…”

“…Though several morphological and cytochemical studies [5][6][7] as well as cytogenetic analyses [8,9] sug gested the involvement of eosinophils in leukaemic clones, the origin of eosinophils is still controversial [5]. In this paper, we present a case of AML associated with a remarkable eosinophilia in relapse.…”