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Nicole Schlegel

Publications and source records attributed to Nicole Schlegel.

6 recordsLinked to original sources
PubMed2004

Thrombophilia and pregnancy complications.

The implications of currently available data on the association of gestational vascular complications with thrombophilia are presented in this consensus report. Screening is recommended for women with the following previous complications: fetal loss including three or more first trimester loss, two or more second trimester loss, or any stillbirth; early, severe or recurrent preeclampsia and severe intrauterine growth restriction. Maternal antithrombotic therapy is currently evaluated in women with thrombophilia and previous complications.

Abortion, Habitual↗
PubMed2003

Neonatal thromboembolism.

In neonates and infants numerous clinical and environmental conditions such as the use of central lines, cardiac diseases and polycythemia, renal diseases such as congenital nephrotic syndrome and neonatal hemolytic uremic syndrome, peripartal asphyxia, infants of diabetic mothers, dehydration, septicemia, necrotizing enterocolitis, acute respiratory distress syndrome, and extracorporeal membrane oxygenation lead to elevated thrombin generation and subsequent thrombus formation. Genetic prothrombotic defects [protein C, protein S and antithrombin deficiency, mutations of coagulation factor V and factor II, elevated lipoprotein (a)] have been established as risk factors for thromboembolic events. The interpretation of laboratory results relies on age-dependent normal reference values. Because appropriate clinical trials are missing in these age groups, treatment recommendations are adapted from small-scale studies in neonates and infants and from guidelines relating to adult patient protocols. Secondary long-term anticoagulation should be administered on an individual basis.

Blood Proteins↗
PubMed2003

Unexpected persistence of platelet hyporeactivity beyond the neonatal period: a flow cytometric study in neonates, infants and older children.

Previous studies, using flow cytometry, have reported a lower platelet reactivity in neonates compared to adults. Only few studies were carried out in older children, and results were controversial in terms of age to reach adult platelet function. We studied a total of 125 healthy neonates, infants and older children, and 15 adults. alphaIIbbeta3 expression on resting and activated platelets was lower in all children, with an impaired capability of alphaIIbbeta3 activation (PAC1 and bound fibrinogen). This defect was observed until the age of fifteen with a gradual recovery with age. In neonates, we observed a defect of GPIalpha internalization, and demonstrated that this defect persisted in older children as well. In contrast with alphaIIbbeta3 integrin activation, we did not observe a gradual age-dependent recovery. These unexpected results point out the need for reference values in childhood.

Adolescent↗
PubMed2002

Thromboembolism in children.

Acquired and inherited prothrombotic risk factors increase the risk of thrombosis in children. This review is based on "milestone" pediatric reports and new literature data (January 2001-February 2002) on the presence of acquired and inherited prothrombotic risk factors, imaging methods, and treatment modalities in pediatric thromboembolism. After confirming clinically suspected thromboembolism with suitable imaging methods, pediatric patients should be screened for common gene mutations (factor V G1691A, prothrombin G20210A and MTHFR C677T genotypes), rare genetic deficiencies (protein C, protein S, antithrombin, and plasminogen), and new candidates for genetic thrombophilia causing elevated levels of lipoprotein(a), and homocysteine, and probable genetic risk factors (elevations in fibrinogen, factor IX, and factor VIIIC, and decreases in factor XII). Data interpretation is based on age-dependent reference ranges or the identification of causative gene mutations/polymorphisms with respect to individual ethnic backgrounds. Pediatric treatment protocols for acute thromboembolism, including thrombolytic and anticoagulant therapy, are mainly adapted from adult patient protocols.

Child↗
PubMed2002

[Evaluation of the STA-R analyzer for the study of neonatal and pediatric hemostasis].

To evaluate the capacities of adaptation of the STA-R analyzer (Diagnostica Stago, Asnieres, France) to the study of pediatric hemostasis, classical studies were undertaken and they have included: (1) Within-run assays (n = 21, 2 control levels) and day-to-day precision studies (n = 20, 2 control levels) for the following tests: prothrombin time (PT), activated partial thromboplastin time (APTT), factor II (FII), factor VII + X (FVII + X), factor V (FV), fibrinogen (fg) and antithrombin (AT); (2) Comparison of the results of APTT, FII, FVII + X, FV and fg assays (in 50 plasmas) obtained with STA-R and STA (analyzer currently used, in our pediatric laboratory). Specific pediatric evaluation has included: (1) Evaluation of the STA-R results for low concentrations of the coagulation factors; (2) Determination of the lowest dead volume; (3) Introduction of peculiar samples among "routine" series. The results showed that within-run assays and day-to-day precision studies have confirmed the good performances of the STA-R. The comparison of the STA-R and STA results from 50 plasmas shows a correlation coefficient of 0.990, 0.995, 0.996, 0.997 and 0.996 for APTT, fg, FII, FVII + V and FV respectively. Such results are confirmed for low concentrations of coagulation factors. The acceptable dead volume could be lowered down to 50 microliters. Very small samples, selected assays and emergencies could be easily introduced among routine series. It is concluded that the STA-R showed very good technical performances. The STA-R is adapted to the routine tests as well as to the very specific samples of neonates and children.

Adolescent↗