[Bone marrow culture, cytochemistry and electron microscopy in agar in patients with preleukemic syndrome and aplastic anemia].

Thirty-seven patients with chronic cytopenia were studied using a CFU-c assay in agar. On the basis of the growth pattern three types of preleukaemic syndrome (PL) and two types of aplastic anaemia were distinguished. Further evaluation of the bone marrow dysfunction was attempted with a combined application of cytochemistry and electron microscopy for the morphologic study of cells proliferating in vitro. Well-defined maturation defects in the growing cells from the bone marrow of patients with PL were demonstrated with cytochemical stainings performed in agar. These results were supported by electron microscopic findings of Auer-body-like inclusions in "statu nascendi" in the vacuoles of preleukaemic cells. On the basis of our results a high risk group of PL for development of overt leukaemia and a group of patients with a grave prognosis in aplastic anaemia were distinguished. The data obtained are relevant for the clinical diagnosis and prognosis of patients with cytopenias.