Zur Ultrastruktur und Cytochemie von eosinophil-myelomonocyt�ren Leuk�mien

Abstract

In the bone marrow of two patients with acute leukemia 46% and 55% of atypical eosinophilic cells were found, respectively. Blood eosinophilia was absent. The N-AS-D-Cl-Esterase reaction of the granules was positive in the first case in 58%, and in the second case in 3% of the eosinophils, as well as the PAS-reaction in all cells of this series. The ultrastructure of the eosinophils reveals nuclear maturation up to hypersegmentation. The maturation of the granules, in part of abnormal size, is arrested at the primary stage. Typical secondary granules with cristalloid cores are lacking. Only in the first case a few, small, semicircular or circular profiles of lamellar substructure are seen in the granules. The cytoplasm of hypersegmentated eosinophils shows an abnormally high glycogen content. Besides the eosinophils, monocytic cells and their precursors proliferate in the bone marrow of the first patient. In the second patient myeloblasts, promyelocytes with Auer rods, and monocytic cells characterize further neoplastic cell population. The elements of the monocytic series can be identified by their ultrastructural features, such as irregular configuration of the nuclei, bundles of cytoplasmatic microfilaments, and numerous small electron-dense lysosomal granules. In both cases the Alpha-Naphthyl-Acetase-Esterase reaction is weakly positive. The findings presented are summarized under the terms "eosinophil-monocytic leukemia" and "eosinophil-myelomonocytic leukemia" (collective term).

Eosinophilic leukaemia: morphological, cytochemical, and electron microscopic studies.

“…Our finding of abnormally high glycogen content in the cells is in agreement with similar findings by Gross (1962), Weinger et al (1975), Wulfhekel et al (1975), Ackerman (1964), and Schaefer et al (1973). According to Ackerman (1964), the high content of glycogen might be due to hyperactivity of phosphorylase, but there is as yet no evidence in support of this suggestion, and other explanations are equally valid; for instance, the high glycogen content could stem from an increased activity of glycogen synthetase or, alternatively, from a decrease or inhibition of glycogen phosphorylase, which degrades glycogen.…”

“…It is our opinion that eosinophilic leukaemia as such is not merely a type of chronic myelogenous leukaemia, as suggested by Benvenisti and Ultmann (1969) and Wulfhekel et al (1975), but rather a separate, discrete disease entity. The present case offers further evidence that the eosinophils form a distinct cell line in the bone marrow.…”