Nouvelle revue francaise d'hematologie最新文献

Leucopenia patient follow-up remains, in terms of laboratory turnaround, a heavy workload due to the leucoconcentrations necessary for evaluating leucocytic formulas. We tested the CD 3500 with the objective of defining its' analytical performances and routine practice. 101 leucopenia samples (< 2.10(9)/l) procured from the onco-hematology department (adults and children) were studied during a 1 month period. The leucocytic formula obtained after leuconcentrations was our reference. The alarm sensitivity, as a whole, was of 97% for a 15.5% specificity. The correlation coefficients (Cell-Dyn/microscope) for polynuclears, lymphocytes and monocytes were respectively 0.889, 0.925 and 0.926. The correlation coefficients observed in both following subgroups: < or = 0.5.10(9)/l and > 0.5.10(9)/l were superposable. In 95% of the cases, the numeric value difference between the two methods attained a maximum of 21% for all neutrophils and lymphocytes and 13% for the monocytes. There was an excellent concordance between both methods for eosinophilia and basophils with confidence intervals of +/-8.8% and +/-2.2%. In practice, we feel that the use of a CD 3500 in post chemotherapy leucopenia, is perfectly adaptable and appreciated for leucocytic formulas, as well as a good exit for aplasia.

The quality tests made during the preparation of labile blood products permit to validate the product and to make sure the making procedures are applied properly. The labile blood products have to correspond to a number of standards set by a ministerial order. It is thus necessary to check the manufacturing unit of some products. On account of the original technology of Cell-Dyn 3500 which associates methods of impedance variation measure analysis and flow cytometric technique analysis on non-marked cells, and of its veterinary modulus permitting counting in extreme values, it seemed to be worth being evaluated in a blood bank quality control laboratory. Linearity was studied from a range of dilutions obtained from high value samples prepared by the centrifugation of blood bags and collection of the buffy coat by Optipress system. The study was performed on 22 samples. The linearity in the counting of red cells, white cells, platelets and haematocrit was measured. Intersample contamination was measured. It focused on the values of platelets and white cells. A sample of high cell concentration prepared in the condition mentioned above and a white cell-reduced blood concentrate were used. The study of repeatability was done by treating 20 times three samples covering a wide range of values of the different parameters of cell numeration. The linearity concerning parameters and the range of the values studied are good (example: from 10 to 3000 10(9)/l for platelets). Contamination is low for white cells and non appreciable for platelets. Repeatability shows excellent variation coefficients.

We present the clinical and immunological features of a rare case of chronic lymphoid leukaemia with lymphoplasmacytoid morphology. The patient was first admitted suffering from weakness, pallor, dyspnoea, marked splenomegaly, hepatomegaly and systemic lymphadenopathy and panhypogammaglobulinaemia. White blood cell count revealed important leukocytosis (220 x 10(9) WBC/l) with 2% neutrophils and 98% lymphoid cells showing lymphoplasmacytoid features, while lymphoid cells of identical morphology severely infiltrated the bone marrow and lymph nodes. The disease, initially controlled by non aggressive chemotherapy over a period of 30 months, later evolved to a clinical and haematological picture suggestive of Richter's syndrome. Immunophenotyping of the leukaemic cells demonstrated a monoclonal expansion of B-cells bearing surface markers of typical CLL (CD5, CD19, CD20, CD21, CD22, CD23, CD24, CD40 and low density IgM+IgD/kappa) and also the CD11c and CD38 antigens. A proportion of these cells expressed activation markers (CD25, CD69 and CD71). Following in vitro activation with TPA or PWM, the cells responded by weak incorporation of 3H-TdR but failed to secrete immunoglobulins. These findings confirm the broad morphological, phenotypical and clinical spectrum of chronic lymphoid leukaemias.

Erythrocyte sedimentation rate (ESR) is mainly used in clinical practice as a screening test for inflammatory diseases and sometimes in the follow-up of patients. However, ESR is highly dependent on erythrocyte aggregation. In this study, using a Sediscan (Becton) automatic device measuring the kinetics of ESR, these results are compared with the measurement of erythrocyte aggregation as determined by laser light backscattering (Erythroaggregometer Affibio). A series of 188 samples from in-patients were tested. Statistical analysis of 13 parameters indicates that 82% of ESR variance may be explained by fibrinogen level, haematocrit and a parameter characterizing erythrocyte aggregation: the aggregation index at 10 s. This correlation was then validated prospectively in 128 other patients and seems to be independent of the underlying disease. Thus ESR in combination with fibrinogen assay and haematocrit may be considered as a simple and economic method to assess erythrocyte aggregation.

Modern therapy of Hodgkin's disease (HD) has contributed to improve long term survival for most patients. However, the problem of HD therapy cannot be considered as solved, since in large scale studies the proportion of individuals who after a period of complete remission die from intercurrent causes yields evidence of an increased mortality rate. In 1989, the establishment of an international data base on HD comprising more than 14,000 cases allowed analysis of survival and causes of death in these patients. Overall, the 10-year, 15-year and 20-year survival rates were 68%, 60% and 51% respectively. Compared with the general population, the increase in mortality was 31% at 15 years, giving a standardized mortality ratio of 7.68 (p < 0.001). Death was related to disease progression in 67.1% of subjects. Among patients who died from causes unrelated to HD or its treatment, second cancer deaths represented the first cause with 38%, followed by infections with 21% and acute myocardial infarction with 13%. This picture justifies the current increasing concern to refine the treatment of HD in order to minimize complications without reducing the overall chance of survival. Treatment choice should take into account the short and long term consequences of each available strategy and Hodgkin's disease patients should be submitted to routine follow-up for the rest of their lives.

Prevention of stroke is a crucial health care issue, as stroke is the third cause of death and the first cause of major disability in developed countries. The established role of platelet aggregation in TIA or minor and major ischaemic stroke has provided the rationale for many randomized trials of antiplatelet agents (aspirin, sulfinpyrazone, dipyridamole alone or in combination with aspirin, suloctidil, ticlopidine). The recent Antiplatelet Trialists' Collaboration (APT) meta-analysis (1994) based on 142 trials involving 100,000 vascular patients confirmed the data of the previous overview (1988). Aspirin, the only drug evaluated for primary prevention of ischaemic events, is not indicated for safety reasons in subjects at low risk of occlusive disease. Compared to control, antiplatelet therapy, notably aspirin which is by far the most widely used agent in trials, provides a 27% risk reduction of stroke, myocardial infarction or vascular death in patients suffering from ischaemic vascular events and a 22% risk reduction of these outcomes in patients having experienced a prior TIA/stroke. Aspirin (around 325 mg/day) and ticlopidine (500 mg/day) are currently the reference drugs for secondary prevention in cerebrovascular patients. The long term efficacy of ticlopidine, a specific antiaggregating agent, has been evaluated in two North American trials involving more than 4,000 patients. TASS showed ticlopidine to be significantly more effective in reducing the incidence of fatal or nonfatal stroke and death than aspirin in patients with TIA or minor stroke. The relative risk reductions over aspirin, the first year of greatest risk, were 41% for stroke and death and 46% for fatal or nonfatal stroke. CATS showed that ticlopidine compared with placebo induces a significant 30% relative risk reduction of stroke, myocardial infarction and vascular death over three years in patients who had suffered a recent thromboembolic stroke. The above results elicit two important issues: the optimal dose of aspirin and its tolerability compared to ticlopidine. The three controlled trials (UK-TIA, SALT, Dutch TIA) which have compared high (> or = 1 g/day) and low dose aspirin (< or = 300 mg/day) or various low doses of aspirin did not give a definite answer on the efficacy of low or very low (30 or 75 mg/day) doses of aspirin for reducing the risk of vascular outcomes in patients with stroke precursors. Even with low doses of aspirin there was still a risk of severe gastrointestinal bleeding, although minor side effects were less frequent.(ABSTRACT TRUNCATED AT 400 WORDS)

The purpose of this work was to study the viscoelastic behaviour of the red blood cell membrane (RBCM) in cells from patients with beta-thalassaemia and to investigate whether the precipitated haemoglobin, which is one of the main features of thalassaemic syndromes, influences the membrane viscosity. RBCM viscosities were determined using the micropipet aspiration method. A negative pressure of about 50 Pa was applied in steps at the membrane surface so as to cause partial aspiration of the cell and the entry process was analyzed automatically by a TV-line analyzer. This analysis enabled estimation of the characteristic times (tau 1, tau 2) and corresponding values of the viscosity (eta 1, eta 2). Results were as follows: eta 1 = (1.87 +/- 0.55) microNs/m and eta 2 = (51.42 +/- 20) microNs/m for erythrocytes from normal donors; eta 1 = (3.97 +/- 0.98) microNs/m and eta 2 = (110.40 +/- 35) microNs/m for erythrocytes from patients. Inclusions (Heinz Bodies) were produced artificially in normal cells and the characteristic times (tau 1, tau 2) and corresponding viscosities (eta 1, eta 2) derived in the same manner. For three types of RBC containing increasing numbers of inclusions, the values were: eta 1 = (3.26 +/- 1.70) microNs/m and eta 2 = (77.33 +/- 46.96) microNs/m; eta 1 = (4.21 +/- 1.49) microNs/m and eta 2 = (129.60 +/- 47.90) microNs/m; eta 1 = (7.93 +/- 2.62) microNs/m and eta 2 = (206.60 +/- 93.19) microNs/m. It is concluded that the association of inclusion bodies with the membrane, either in disease or through artificial production, increases the membrane viscosity.

Arterial and venous thrombotic complications have being increasingly recognized as a major cause of mortality and morbidity in polycythemia vera. The risk can be increased with the treatment. Actually, we can not precisely evaluate the risk of previous venous and arterial lesions, however we have non invasive techniques that permit an accurate evaluation of the vascular bed in patients without recent thrombotic events. The ratio cost-efficacy of the vascular explorations has to be discussed according to the risk factors. In patients with a recent arterial thrombotic event, extensive vascular investigations are mandatory.

The treatment of polycythemia vera with 32phosphorus (32P) raises two problems: 1) what is its therapeutic efficacity? 2) Does the use of 32P increase the risk of acute leukemia? The large series of treated patients have shown the remarkable efficacy of 32P. This is particularly evident when comparing the recent series of patients treated with 32P with those of Videbaek whose patients were treated by phlebotomies only. Patients are treated one time with 3.7 x 10(6) mBq (0.1 mCi) of 33P per kg of body weight. Granulocytes and platelets are rapidly affected, whereas red cells show a response 3 months later due to their longer survival. Remission lasts from a few months to three years. If the result is not satisfactory, another dose can be given 3 months after the first one. Resistance to 32P may arise but may be reversible after a course of chemotherapy. The clear therapeutic effect of 32P renders it especially valuable for patients with a high vascular risk. Some authors have claimed that polycythemia vera evolves towards acute leukemia, but Modan's study has demonstrated that 32P is indeed responsible for the occurrence of acute leukemia; this has been largely confirmed by others. The dose to the bone marrow is not negligible and the leukemic incidence following the treatment is a factor which limits its indication. Trials were conducted to search for therapies with alkylating agents, such as Chlorambucil or Busulphan, which would be less leukemogenic. The Polycythemia Vera Study Group found that Chlorambucil was at least 2.3 fold more leukemogenic than 32P. The EORTC compared the leukemogenic effect of 32P with that of Busulphan.(ABSTRACT TRUNCATED AT 250 WORDS)