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Asnières-sur-Seine, France

Perrin J.,Nancy University Hospital Center | Perrin J.,French Institute of Health and Medical Research | Depasse F.,Diagnostica Stago | Lecompte T.,Hopitaux Universitaires Of Geneva Hug
Thrombosis Research | Year: 2015

Background Calibrated Automated Thrombography (CAT) has been widely used to assess in vitro thrombin generation as an informative intermediary phenotype of coagulation. Interlaboratory exercises have documented a worrisome poor reproducibility. There are some data on the normalisation with an appropriate external reference plasma (RP). This multicentre study of the French-speaking CAT Club aimed at providing further evidence for the usefulness of such a normalisation. Materials and Methods Lyophilised aliquots of a RP along with 3 plasmas (P1 = normal; P2 = hypo-; P3 = hypercoagulable) were sent to 34 laboratories (corresponding to 38 instruments). CAT was studied using 1 and 5 pM tissue factor and other dedicated reagents. Normalisation with the local RP in use in the laboratory could also be performed. Interlaboratory CVs were calculated for each plasma before and after normalisation. Results Regarding endogenous thrombin potential, a good discrimination between the 3 plasmas was achieved in all laboratories but there was no overlap after normalisation only. CVs were generally not reduced with the use of local RP but were generally improved with normalisation using the external RP, often becoming lower than 10%. Regarding P2 however, the benefit of normalisation was poor, and there were analytical difficulties as well, some laboratories being unable to get a useable signal. Conclusions We confirm that normalisation of CAT results with a suitable external RP is useful in "real life" practice as it often permits an acceptable level of interlaboratory variability. In case of frank hypocoagulability, further improvements are required to get reliable, potentially clinically relevant results. © 2015 Elsevier Ltd.

Walsh J.P.,Sir Charles Gairdner Hospital | Walsh J.P.,University of Western Australia | Bremner A.P.,University of Western Australia | Feddema P.,Diagnostica Stago | And 5 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2010

Context: Longitudinal studies of risk factors for hypothyroidism are required to inform debate regarding the TSH reference range. There are limited longitudinal data on the predictive value of thyroid antibodies measured by automated immunoassay (as opposed to semiquantitative methods). Methods: We measured TSH, free T4, thyroid peroxidase antibodies (TPOAbs), and thyroglobulin antibodies (TgAbs) using the Immulite platformonserafrom1184participants in the1981and1994 Busselton Health Surveys. Outcome measures at follow-up were hypothyroidism, defined as TSH greater than 4.0 mU/liter or on thyroxine treatment; and overt hypothyroidism, defined as TSH above 10.0 mU/liter or on thyroxine treatment. Receiver-operator characteristic analysis was used to determine optimal cutoffs for baseline TSH, TPOAbs, and TgAbs as predictors of hypothyroidism. Results: At 13 yr follow-up, 110 subjects (84 women) had hypothyroidism, of whom 42 (38 women) had overt hypothyroidism. Optimal cutoffs for predicting hypothyroidism were baseline TSH above 2.5 mU/liter, TPOAbs above 29 kIU/liter, and TgAbs above 22 kIU/liter, compared with reference range upper limits of 4.0 mU/liter, 35 kIU/liter, and 55 kIU/liter, respectively. Inwomenwith positive thyroid antibodies (TPOAbs or TgAbs), the prevalence of hypothyroidism at follow-up (with 95% confidence intervals) was 12.0% (3.0-21.0%) when baseline TSH was 2.5 mU/liter or less, 55.2% (37.1-73.3%) for TSH between 2.5 and 4.0 mU/liter, and 85.7% (74.1-97.3%) for TSH above 4.0 mU/liter. Conclusions: The use of TSH cutoffs of 2.5 and 4.0 mU/liter, combined with thyroid antibodies, provides a clinically useful estimate of the long-term risk of hypothyroidism. Copyright © 2010 by The Endocrine Society.

Bremner A.P.,University of Western Australia | Feddema P.,Diagnostica Stago | Leedman P.J.,University of Western Australia | Brown S.J.,Sir Charles Gairdner Hospital | And 9 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2012

Context: In cross-sectional studies, serum TSH concentrations increase with age. This has not been examined longitudinally, and it is uncertain whether the TSH increase reflects healthy aging or occult thyroid failure. Methods: We measured serum TSH, free T4, thyroid peroxidase, and thyroglobulin antibodies in 1100 participants in the 1981 and 1994 Busselton Health Surveys and derived a reference group of 908 individuals without thyroid disease or thyroid antibodies. We examined changes in thyroid function longitudinally and, in 781 participants, explored associations with the CAPZB polymorphism rs10917469. Results: At 13 yr follow-up, mean serum TSH increased from 1.49 to 1.81 mU/liter, a change in mean TSH (ATSH) of 0.32 mU/liter [95% confidence interval (CI) 0.27, 0.38, P < 0.001], whereas mean free T4 concentration was unchanged (16.6 vs. 16.6 pmol/liter, P = 0.7). The TSH increase was most marked in the elderly, such that gender-adjusted ATSH increased by 0.08 mU/liter (95% CI 0.04, 0.11) for each decade of baseline age. People with higher baseline TSH values had proportionally smaller increases in TSH, with each additional 1.0 mU/liter of baseline TSH associated with a 0.13 mU/liter decrease (age and gender adjusted) in ATSH (95% CI 0.09, 0.16). The ATSH did not differ significantly by CAPZB genotype. Conclusions: Aging is associated with increased serum TSH concentrations, with no change in free T4 concentrations. The largest TSH increase is in people with the lowest TSH at baseline. This suggests that the TSH increase arises from age-related alteration in the TSH set point or reduced TSH bioactivity rather than occult thyroid disease. Copyright © 2012 by The Endocrine Society.


Diagnostica Stago | Date: 2015-07-28

Reagents of chemical or biological origin to be used for analyses, reactions, assays and tests in laboratories for human and veterinary medicine.

Diagnostica Stago | Date: 2015-09-01

Apparatus used for automatic biological sampling in the field of medical analysis.

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