Biomedical subjects

T Lecompte

Publications and source records attributed to T Lecompte.

154 records · Page 9Linked to original sources

PubMedDate not supplied

[Use of ecarin clotting time in whole blood for monitoring recombinant hirudine treatment during cardiopulmonary bypass in patients with heparin-induced thrombocytopenia].

Lepirudin (Refludan is a recombinant hirudin, approved for anticoagulation treatment of heparin-induced thrombocytopenia patients with thrombosis. We report here our method for laboratory monitoring with ecarin clotting time (ECT) of hirudin therapy as anticoagulation for cardiac surgery. Ecarin is extracted from the Echis carinatus snake venom and directly converts prothrombin to its intermediate, meizothrombin. This one binds in a stoechiometric way to hirudin to be proportioned in whole blood. The activation of coagulation starts up only when the totality of the hirudin is bound to the meizothrombin. To minimize the effect of dilution related to the CEC on the prothrombin and fibrinogen levels, thus lengthening the ECT, the specimen to be tested is diluted with normal whole blood. In 1997, when we have performed our first surgery with cardiopulmonary bypass, only one team (Pötzsch et al., 1997) had described the use of the ECT in whole blood. We describe in this work our assay to dose hirudin with ECT after dilution in whole blood. This assay was used during 8 CEC among 7 patients affected with HIT (n = 6) or potentially sensitized with heparin (n = 1). Experimental conditions and interpretation of the assay are reported here. This test is fast enough to provide useful information for adjusting the dose during cardiopulmonary bypass.

Aged↗

PubMedDate not supplied

[Reproductibility of the morphological identification of schisocytes and evaluation of non observer-dependent methods].

Schistocytes are red blood cell fragments observed on a blood smear. They are a mark of mechanical haemolytic anaemias whose group of the thrombotic micro-angiopathies requires an urgent treatment. The detection of the schistocytes and sometimes their quantification are thus of primary importance. To evaluate this search for schistocytes, several surveys of practice were carried out (1999-2003) including pictures of blood fields (identification of schistocytes among abnormal red blood cells) near biologists of variable level of specialization. The aim was to try to lead to a consensus, in particular for the morphological criterias of identification. Our results indicated that: 1) the biologists are badly sensitized with the importance of this research and the consequences of their response for the diagnosis; 2) the morphological identification of the schistocytes is difficult with an important variability of the criteria according to the observers. An investigation overviewed by the French Group of Cellular Hematology (Delphi method) allowed the development of a morphological consensus (fragments of triangular/crescent/helmet forms with rectilinear zone testifying to the zone of break). In order to cancel the observer-dependent identification of the schistocytes, a software of morphometric analysis (Q-WIN, Leica) was developed for sorting, starting from digitalized microscopic fields, the fragmented - among the normal - red blood cells. The results appeared encouraging, but not yet optimized. An automated analyzer (Bayer ADVIA 120) was also evaluated for the measurement of the schizocytes ("fragmented red blood cells" parameter). The moderate over-estimation of the real schizocytes (+ 0,4%) encouraged to observe the clinical value of the fragmented red blood cells detection in a group of patients that undergone a bone-marrow transplantation. The predictive value of the test (98%) was satisfactory.

Erythrocyte Count↗

PubMedDate not supplied

[Thrombocytopenia: clinicobiologic validation and classification].

Thrombocytopenia occurs frequently. We will illustrate, through the presentation of a clinical case, the difficulties encountered to identify and characterize thrombocytopenia. The clinicobiological validation of a low platelet count implies, at the same time, the biologist, who must assume the validation of numeration while mentioning the morphological characteristics of the platelets and other blood cells, as well as the clinician who must interpret these data according to the clinical context. Firstly, we will detail the basic rules to correctly ensure this validation. Secondly, we will see which are the arguments which that make it possible to direct the diagnosis towards an acquired or inherited thrombocytopenia. Lastly, we will approach the classification of inherited thrombocytopenias.

Female↗

PubMedDate not supplied

[Screening for iron deficiency in menstruating women: an audit in general medical practice].

To evaluate their own performance in the screening for iron deficiency in menstruating woman, 58 general practitioners have searched in their case-histories the results of serum ferritin or serum iron associated to transferrin saturation dating from less than five years. That observation has been repeated two years later by 25 of them. The progression of the screening among the general practitioners who accepted to realize this audit was clear: from 45.1% to 59.1% women screened on the total of menstruating women aged over 18 and regularly consulting in consultations. The GP's participation in Lorraine remained low (2.7%), in spite of the choice of a frequent medical disorder, a simple procedure and a large diffusion.

Adolescent↗

PubMedDate not supplied

[A case of de novo acute basophilic leukaemia: diagnostic criteria and review of the literature].

We report a case of a de novo acute basophilic leukaemia, revealed by an infectious pneumopathy in a 73 year old man. The full blood count revealed an hyperleucocytosis associated with an unregenerative normocytic normochrom anaemia and a thrombocytopenia. The blood and bone marrow smears showed a mixture of undifferentiated blast cells and basophiloblasts (high nucleo-cytoplasmic ratio, coarse basophilic cytoplasmic granules), along with basophilic precursors and basophilic polymorphonuclears. All the blasts were MPO negative but positive for the toluidine blue metachromatic coloration, which is considered as consistent with basophilic lineage. Immunophenotypic studies showed myeloid blasts, without maturity marker, CD 117 negative and CD203 cytoplasmic positive, the latter known to be highly representative of the basophilic lineage. This very clear-cut phenotype, associated with the morphology of cells, were arguments to ascertain the basophilic lineage of the blasts without the need of electron microscopic study. Cytogenetic and RNA analysis revealed the presence of a Philadelphia chromosome and of a BCR-ABL transcript with the unusual junction e6a2. Thus, imatinib was added to the conventional chimiotherapy and the patient is currently in complete remission. This clinical prompted allows us to review the literature on acute basophilic leukaemia and to state on the different diagnostic criteria of this rare disorder.

Aged↗

PubMedDate not supplied

[Incubated osmotic fragility test does not exclude red blood cell membrane disorders! About a case of hereditary elliptocytosis].

We report a case of hereditary elliptocytosis in an infant diagnosed a few months after the birth, in a context of regenerative normocytic normochromic anaemia. The investigations, including incubated osmotic fragility, erythrocytic enzymes study and haemoglobin electrophoresis, were not contributive. Only the persistence of elongated (or cigar-shaped) erythrocytes on blood smears was noted. Hereditary elliptocytosis was confirmed by specialized investigations (rheological study and erythrocytic membrane proteins electrophoresis). Investigations in the mother were realized and led to the discovery of a similar biological pattern. Hereditary elliptocytosis is a red blood cell membrane disorder due to the defect in cytoskeleton proteins (spectrin or 4.1), leading to the loss of deformability properties of erythrocytes. This disorder is considered as rare; however, its incidence is probably underestimated because most cases are pauci- or asymptomatic and the discovery is often fortuitous. The absence of detection of this defect by incubated osmotic fragility should not discard the hypothesis of erythrocytes membrane disorders. The persistent observation of elongated erythrocytes on blood smear must encourage the biologist to evocate a hereditary elliptocytosis.

Blood Protein Electrophoresis↗

PubMedDate not supplied

[Prostanoids and hemostasis].

Thromboxane A2 (TXA2) and prostacyclin (two prostanoids) are produced from arachidonic acid through the cycloxygenase pathway. The enzyme cyclooxygenase is inhibited by aspirin. Prostanoids are short-lived and thus exert their effects locally. Activated platelets synthetize TXA2 which reinforces activation of those platelets and platelets in the vicinity of the former. Complete activation however can occur in the absence of TXA2 synthesis. Prostacyclin is able to block all the platelet responses, but this would be achieved in vivo together with intense vasodilation. Primary adhesion remains unaffected, since it does not require platelet activation. There are other molecules endowed with inhibitory effects on platelets: PGD2, PGE1, adenosine, and EDRF (nitric oxide). These molecules, and prostacyclin, also have effects on other cells than platelets and smooth muscle cells: leukocytes, endothelial cells. Clinical investigations on the prostanoid system in physiology and pathology of the cardiovascular system have been hampered by analytical problems. Taking into account all these restrictions, a rational pharmacological approach is difficult, but newer molecules with dual and selective activity against TXA2 (both inhibitor of TX-synthetase and antagonist at the TXA2-receptor level) seem promising as anti-thrombotic agents.

Epoprostenol↗

PubMedDate not supplied

[Radiologic aspects of noncalculous inflammation of the biliary tract in AIDS].

Six cases of non-lithiasic cholecystitis and 7 cases of inflammatory cholangitis caused by cryptosporidium and/or cytomegalovirus infections have been studied in HIV-1 + patients. All patients were examined with ultrasound and 5 with computed tomography (CT). The appearance is the same as that described for non-lithiasic cholecystitis (pain when the ultrasound probe is applied, thickened gallbladder wall) and sclerosing cholangitis (dilatation and/or stenosis of the bile duct, thickened gallbladder wall). The ultrasound or CT examination of HIV + patients with gallbladder involvement is sufficient to guide treatment when a thickened gallbladder wall is demonstrated. On the other hand, bile duct opacification is the only method allowing the accurate assessment of the extent of lesions in cholangitis, on which the indication for eventual sphincterotomy is based.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

[A survey on the practice of drug prescription in hospitals. Concepts and methodology].

A clinical practice survey, if patient focused, identifies and analyses complexity of drug use. It is not a clinical audit whose aim is to compare observed practice with predetermined criteria. A clinical practice survey is useful when a problem exists in a low evidence based clinical area or to elaborate clinical guidelines. Implementation is based on epidemiological methodology and project management and needs a framework determined by a facilitator (trained in quality improvement methods and expert in the clinical area concerned), planning (the more higher the number of wards, the higher the complexity) and the project guidelines must be respected. Since lack of physician involvement is a drawback, support provided by the quality centre (if it exists) must be limited to technical aspects. It is important to appreciate the level of quality culture of the organization and the project must be approved by the hospital manager.

Data Interpretation, Statistical↗

PubMedDate not supplied

[Thrombocytopenia due to heparin therapy. Use of danaparoid (Orgaran), 13 monocentric cases under authorization of temporary prescription (ATU)].

Since September 1994, danaparoid (Orgaran), a heparinoid, has been used in our centre to treat patients with thrombocytopenia occurring during heparin therapy and who need continuing antithrombotic therapy. We carried out a retrospective study using clinical and biological data on the first 13 consecutive patients treated with danaparoid (for 1 to 18 consecutive days). The platelet count returned to normal for ten patients, but one patient died having contracted a severe sepsis and bleeding occurred in one patient with acute renal failure. In the three other cases, the diagnosis of heparin induced thrombocytopenia (HIT) was in retrospect unlikely and the death of these patients was related to severe underlying diseases which were held responsible for thrombocytopenia. We confirm that danaparoid appears to be an effective, well-tolerated substitute for heparin in HIT patients. The French regulation Temporary Authorization for Prescribing Medicines allowed the prompt use of this as yet unmarketed drug and collection of reliable and pertinent data.

Adult↗