Aim. To characterize clinical symptoms, course, immediate and long-term treatment results in young patients with hair cell leukemia (HCL). Material and methods. The data on 41 HCL patients were analysed. The diagnosis was made by standard diagnostic protocol for HCL detection. Results. The analysis of the age of 160 HCL patients studied demonstrated high (26%) incidence of HCL at young age. Young patients with HCL had special clinical manifestations and specific long-term outcomes of treatment with standard schemes. Conclusion. Differences in occurrence of recurrences after standard therapy make it necessary to consider young HCL patients as a separate group who need adjuvant treatment to prolong remission.

Under the present conditions, the competitive capacity of a health care facility is provided by the high level and timeliness of diagnosis of disease. The diagnosis of the types of acute leukemia (AL) may be accomplished immunologically, by using a 33-marker panel and without consideration of the morphocytochemical parameters of blast cells. But such an approach complicates and prolongs the examination of patients with AL. Moreover, morphocytochemical data more exactly define the stages of blast cell differentiation than does the immunological phenotype. Their preparation methods are simple and cost-effective. Only M0, M6, and M7 forms of leukemia require compulsory blast cell phenotyping, particularly in the differential diagnosis of acute myeloid leukemia and acute lymphoblastic leukemia. Search for new markers of leukemia cells, including lesions at the chromosomal or molecular levels, is under way. Some of them are only of theoretical value while other markers have been already used by hematologists to diagnose leukemia. Standardization in this essence is the self-assessment of a facility and reference comparison, which are based on the principles of its orientation to the patient, the adjusted system for controlling the quality of health care that is up to the world standards rather than the compliance with the state-regulated standard. The present paper discusses the ways of establishing the uniform rates and requirements for the morphocytochemical diagnosis of acute leukemias.

AIM:To find out if the RBC ferritin elevation can serve as an additional criterion of inefficient erythropoiesis during progression of chronic myeloid leukemia (CML) and in various types of refractory anemia.MATERIAL AND METHODS:The study group consisted of 56 MDS patients and 73 patients at various stages of CML. 20 healthy donors and 105 patients with verified inefficient erythropoiesis (20--with B12 deficiency before and after the treatment, 85--with beta-thalassemia) were the controls. A ferritin level was measured by radioimmunoassay in RBC hemolysates.RESULTS:The RBC ferritin level in all types of refractory anemia was elevated throughout the disease course, increasing with the development of transfusion dependency. The CML progression was also accompanied by RBC ferritin level elevation associated with abnormal erythroid cell accumulation and elevation of intracellular PAS-positive substance (p < 0.05).CONCLUSION:RBC ferritin level elevation can be considered as an additional biochemical criterion of inefficient erythropoiesis that may be useful in differentiation of anemias, adequate therapy selection and follow-up of erythropoiesis.

AIM:To evaluate the efficacy of cyclosporin A (CyA) at different stages of immunosuppressive therapy (IST) in patients with aplastic anemia (AA).MATERIALS AND METHODS:The efficacy of CyA was studied in 56 patients with AA. The agent was orally given in an initial dose of 10 mg/kg as solution or capsules. Its daily dose during a treatment course varies with the serum CyA levels and clinical tolerance. CyA was used in 17 patients at the first stage of treatment, in 8 with recurrent AA, and in 31 after ineffective previous therapy (antilymphocytic globulin therapy--ALGT, splenectomy). Erythropoiesis was evaluated by the count of erythrokaryocytes and by relative erythroid hyperplasia of the bone marrow and by using erythrokaryocytic PAS reaction, by calculating the total count of sideroblasts and ringed sideroblasts.RESULTS:A positive response was obtained in 41% of the patients with AA. Its pattern depended on the severity of AA, on CyA use regimens, and treatment duration: when treatment with CyA lasted 6-12 months, its efficacy considerably increased (positive responses in severe AA and mild AA being in 64 and 94%, respectively). It has been found that high (over 6%) baseline bone marrow ringed sideroblasts in patients with AA may be regarded as a poor predictor in the context of the efficacy of this agent.CONCLUSION:CyA is recommended for combined IST in patients with AA at the second stage of treatment (after antilymphocytic globulin administration) in order to perform long-term (12-month) immunosuppression by choosing the optimum dose on an individual basis and by continuously monitoring the quality of a response.

Morphology of peripheral blood erythrocytes was studied in patients with acute leukemia and aplastic anemia by a Russian cytoanalyzer Mekos-C. Twenty-eight patients with acute myeloblastic leukemia, 15 with acute lymphoblastic leukemia, and 11 with aplastic anemia were examined. Erythrocytes (n = 500) were examined in fixed non-stained blood smears. Hemoglobin content and morphometric parameters of each cell were studied and automatic classification of cells was carried out. The data of computer morphodensitometry are compatible with the data of cytochemical studies of the bone marrow erythroid cells (PAS reaction after McManus). The results indicate circulation of erythrocyte subpopulations differing by shape and other signs (hemoglobin content, section area, shape factor) in the blood of patients with acute leukemia and aplastic anemia. The share of pathological erythrocytes in the peripheral blood reflects failure of erythropoiesis.

According to current concepts, pluripotent cells proliferate and differentiate into "committed" precursors. These committed precursors divide, mature, and give rise to red cells, granulocytes, monocytes, and platelets of the blood. The life span of mature circulating cells being short, and their populations in the blood very stable, a constant and strict regulation of hematopoiesis is needed. The regulation of hematopoiesis is believed to be mediated through precursor cell interaction with specific molecules (glycoproteins) in their microenvironment. Soluble forms of these molecules are termed "hematopoietic growth factors" and include erythropoietin, colony-stimulating factors, interleukins, and stem cell factors. Hematopoietic growth factors not only stimulate the proliferation of precursor cells, but activate the differentiation program and maintain the viability of these cells as well. The normal fate of precursor cells devoid of these factors is programmed suicide. The morphology of such cell death is usually that of apoptosis, rather than of necrosis. The concept of apoptosis was proposed 22 years ago. Apoptosis is a widespread and morphologically distinct process of cell death. The significance of apoptosis stems from its active nature and its ability of controlling biological systems. The present review of published and authors' own data describes apoptosis morphology and presents evidence of the participation of cell reactions of this type in hematopoiesis regulation. The major point in the review is the balance of three normal processes: proliferation, differentiation, and apoptosis, which maintains the homeostasis of hematopoiesis, similarly as of any other cell system; it is well illustrated by recent findings in experimental and clinical hematology.

In search for markers of tumor cell resistance to cytostatic drugs, cytologic characteristics were compared of resistant and sensitive to rubomycin variants of mouse P-388 leukemia. Morphocytochemical, morphometrical and cytogenetic investigations were performed as well as measurements of intracellular pH. As shown by the fluorescent test, pH levels in rubomycin-sensitive and resistant subpopulations differed. This fact evidences an important role of intracellular pH in inducing the resistance and revealed some mechanisms of rubomycin-resistant tumor cell selection.