Definition and significance of high positivity aCL ELISA.

We conducted a prospective study of anticardiolipin antibody (aCL) testing, performed in our university hospital. Among 6321 consecutive patients tested for both IgG and IgM aCL, 91 patients with medium or high positivity (>99th percentile) had a subsequent confirmatory test. Among them, 53 had a persistent positivity at 12 weeks. In this real world setting, patients with transient positivity had lower values than patients with persistent positivity.

[Anticoagulants drugs direct trombin inhibitors]. / Les anticoagulants inhibiteurs directs de la thrombine.

The aim of this review is to explain the central role of thrombin in haemostasis and the main pharmacological features of the anticoagulants that are direct inhibitors of thrombin, with emphasis on orally active small molecules. Owing to the complexity of the clotting system only well designed and conducted studies can tell us which drug is the most useful, safe and convenient to limit each type of thrombosis and what are the appropriate dosage and management. Parenterally administered direct thrombin inhibitors require laboratory monitoring, whereas dabigatran, orally active, does not.

[A case of cutaneous and mucous haemorrhage secondary to vitamin K deficiency in hyperemesis gravidarum]. / Un cas d'hémorragie cutanéomuqueuse secondaire à un déficit d'apport en vitamine K dans le syndrome d'hyperemesis gravidarum.

The frequency of the syndrome of hyperemesis gravidarum (HG) varies from 0.1 to 2% according to the literature. The complications are generally benign. Some of them can compromise the life outcome. Only two cases of HG with bleeding disorder (major epitasis) related to a vitamin K deficiency were previous reported. Here is described a third case related to a vitamin deficiency K. It is characterized by a skin and mucosa haemorrhage (gingivorrhagias; bleeding in urine; bruises at the points of puncture) and by the necessity to treat her in emergency with fresh frozen plasma before intravenous vitamin K as soon as the diagnosis of vitamin K deficiency was done. The indication of the use of frozen fresh plasma is discussed.

[Multiple osteonecroses and venous thrombosis: one case of patient with a novel mutation of protein C (N102S) and heterozygous for FV Leiden]. / Ostéonécroses et thromboses veineuses multiples : un cas de patient porteur d'une nouvelle mutation de la protéine C (N102S) et hétérozygote pour le facteur V Leiden.

The association of a thrombo-embolic venous disease and multiple osteonecroses occurring in the presence of biological risk factors for thrombosis is rarely described in the literature. We report here the case of a 35-year old patient with such clinical manifestations. This patient is heterozygous for a novel mutation of the protein C gene (N102S) and for FV Leiden polymorphism. The clinical history is characterized by numerous thrombo-embolic venous episodes associated with several episodes of epiphysis osteonecrosis requiring two hip total prostheses and two knee total prostheses. The particular clinical features here are the multiple osteonecroses and the unusual localisation of brain and genital thromboses. The absence of both venous thromboembolic and osteonecrosis events in the relatives presenting the same genetic pattern suggests broad phenotype variations in the clinical expression of these genetic abnormalities. In osteonecrosis associated with thrombophilia, some authors have proposed treatment with stanazolol, which increase circulating protein C concentration. The effectiveness of this drug among such patients should be evaluated by clinical studies.

[Discrepancy between two methods of D-dimers measurement: one case of human anti-mouse antibody interference]. / Incohérence entre deux méthodes de dosage des D-dimères: un cas d'interférence d'anticorps humain anti-souris.

Quantification of D-dimers is the major biometry step in the diagnostic of an episode of the venous thromboembolic disease. The measurement of D-dimers can be performed with ELISA or immunoturbidimetric methods suited to emergency, using a mouse monoclonal antibody as capture and/or revelation antibody. Therefore, the presence in patient's plasma of human antibody mouse (HAMA) that binds the mouse antiglobulin used in immunoassays can lead to false negative or false positive results. In a young woman presenting repetitive thoracic pain suggestive of a pulmonary embolism, a major discrepancy was found between one result of D-dimers above the cut-off with an immunoturbidimetric method (STA Liatest D-DI; Diagnostica Stago) and one result below the cut-off with a sandwich method (Vidas D-Dimer Exclusion; bioMérieux). HAMA, which is known to be responsible for this type of discrepancy, was detected in the patient serum. The false positive result probably impaired with the management of patient. Taking in charge the patient should take into account the possible presence of this antibody. Interference by heterophilic antibodies is not easily detected by the laboratory. Even if their frequency is low, it remains a difficult problem for the biologist. Suspicion generally arises from inconsistency between the clinical data and immunoassay results. A good communication between physician and biologist should avoid to providing false negative or positive results.

[Persistent thrombocytopenia in a child: morphological examination of blood platelets established the diagnosis of Wiskott-Aldrich syndrome]. / Thrombopénie persistante chez un enfant: l'examen morphologique des plaquettes a conduit au diagnostic de syndrome de Wiskott-Aldrich.

Thrombocytopenia frequently occurs in laboratory practice. The present work illustrates, through the presentation of a case report of Wiskott-Aldrich syndrome, the difficulties encountered to identify and characterize thrombocytopenia. The clinicobiological validation of a low platelet count involves both 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 physician who has to interpret these data according to the clinical context.

[Willebrand factor deficiency and septorhinoplasty]. / Déficit en facteur Willebrand et septorhinoplastie.

INTRODUCTION: Willebrand disease can be diagnosed late, sometimes only when hemorrhage complicates surgery. French guidelines do not recommend investigation before surgery when no personal or familial hemorrhagic diathesis is reported. OBJECTIVE: To consider the advantages of Willebrand factor dosage before septorhinoplasty. METHOD: Three cases of septorhinoplasty and Willebrand factor deficiency complicated with hemorrhage compromising the functional result are reported. The routine tests (platelet count, bleeding time, and activated partial thromboplastin time) and Willebrand factor dosage were done before or after surgery. RESULTS: In the three cases, no personal or familiar hemorrhagic diathesis was found. For two cases, a hemorrhage occurred during surgery. One of them had prolonged and repeated nose bleedings after surgery. In this case, iterative packings damaged the result of surgery and a new rhinoplasty had to be done. In one case, a prolonged activated partial thromboplastin time before surgery revealed a Willebrand factor deficiency, leading to prophylactic treatment (desmopressin) of bleeding. CONCLUSION: The cases described suggest that systematic dosage of Willebrand factor before septorhinoplasty could be advantageous and that functional prognosis can be impaired by uncontrolled epistaxis.

[Use of ecarin clotting time in whole blood for monitoring recombinant hirudine treatment during cardiopulmonary bypass in patients with heparin-induced thrombocytopenia]. / Utilisation du temps de coagulation par l'écarine en sang total pour la surveillance d'un traitement anticoagulant par lépirudine (Refludan au cours de circulation extracorporelle dans un contexte de thrombopénie induite par l'héparine.

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.

[A case of celiac disease with late diagnosis by very long prothrombin and activated partial prothrombin times]. / Un cas de maladie coeliaque révélée tardivement par un temps de Quick et un temps de céphaline avec activateur très allongés.

Coeliac disease is usually revealed by intestinal symptoms, but less frequently by deficiency symptoms. Early screening is very important to avoid with appropriate diet an intestinal lymphoma or epidermoid cancer. We report here the case of a 68-year old woman where coeliac disease was pointed out by very long Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT). Clinical examination was strictly normal except for leanness, a small height, and several diarrhoea episodes 3 or 4 times a year. Other blood tests showed a macrocytic anemia, a fibrinogen level slightly above the upper limit, a decreased proteinaemia and albuminaemia, and a sideraemia at the lower normal limit. Liver tests pointed to a cytolysis. Vitamin K-dependent factors were decreased. A perfusion of vitamin-K allowed getting a normal PT. Duodenofiberscopy with biopsy allowed the diagnosis of coeliac disease. Neither lymphoma nor epidermoid cancer were detected. A gluten-free diet allowed the disappearing of digestive symptoms, weight rising and return to a normal PT. Searching for a coeliac disease is therefore relevant in aged patients even when very faint clinical or biological symptoms of malabsorption appear, particularly when PT is longer than the control with decreased vitamin-K dependant factors.

[The direct antiglobulin and elution tests: evaluation of quality control in Blood Transfusion Centers]. / Test direct à l'antiglobuline et élution directe: bilan d'un contrôle de qualité d'établissements de transfusion sanguine. Groupe Immunohématologie de la Société Française de Transfusion Sanguine.

The Société Française de Transfusion Sanguine and the Centre National de Référence pour les Groupes Sanguins performed a quality control to evaluate the performances of two serological tests: the Direct Antiglobulin Test (DAT) and the Elution test. Among the 110 Blood Transfusion Centers participating in this control, 80 (73%) returned a result. Of these, 68 results were correct for the DAT (85%; positive for type IgG) and 31 results were correct for the elution (39%; anti-FY1). This control gave the opportunity to confirm the main procedures used in routine testing on a national scale. The analysis of the results underlines the importance of the choice of a standardized technique for these tests. Such controls are useful to appreciate the quality of the routine tests and to find the means to improve them.