Evaluation of an Immunoturbidimetric Assay for Haemoglobin A1c on a Cobas® Mira S Analyser

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Rogers v. Robson: Increased Malpractice Liability for Insurance Defense Counsel, 14 J. Marshall L. Rev. 589 (1981)

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Prediction of impending type 1 diabetes through automated dual-label measurement of proinsulin:C-peptide ratio

Background : The hyperglycemic clamp test, the gold standard of beta cell function, predicts impending type 1 diabetes in islet autoantibody-positive individuals, but the latter may benefit from less invasive function tests such as the proinsulin: C-peptide ratio (PI:C). The present study aims to optimize precision of PI:C measurements by automating a dual-label trefoil-type time-resolved fluorescence immunoassay (TT-TRFIA), and to compare its diagnostic performance for predicting type 1 diabetes with that of clamp-derived C-peptide release. Methods : Between-day imprecision (n = 20) and split-sample analysis (n = 95) were used to compare TT-TRFIA (Auto Delfia, Perkin-Elmer) with separate methods for proinsulin (in-house TRFIA) and C-peptide (Elecsys, Roche). High-risk multiple autoantibody-positive firstdegree relatives (n = 49; age 5-39) were tested for fasting PI:C, HOMA2-IR and hyperglycemic clamp and followed for 20-57 months (interquartile range). Results : TT-TRFIA values for proinsulin, C-peptide and PI:C correlated significantly (r(2) = 0.96-0.99; P<0.001) with results obtained with separate methods. TT-TRFIA achieved better between-day % CV for PI:C at three different levels (4.5-7.1 vs 6.7-9.5 for separate methods). In high-risk relatives fasting PI:C was significantly and inversely correlated ( r(s) = -0.596; P<0.001) with first-phase C-peptide release during clamp ( also with second phase release, only available for age 12-39 years; n = 31), but only after normalization for HOMA2-IR. In ROC- and Cox regression analysis, HOMA2-IR-corrected PI:C predicted 2-year progression to diabetes equally well as clamp-derived C-peptide release. Conclusions : The reproducibility of PI:C benefits from the automated simultaneous determination of both hormones. HOMA2-IR-corrected PI:C may serve as a minimally invasive alternative to the more tedious hyperglycemic clamp test

A novel LIPS assay for insulin autoantibodies

Insulin autoantibodies (IAA) are often the first marker of autoimmunity detected in children in the preclinical phase of type 1 diabetes (T1D). Currently, the vast majority of laboratories adopt the radiobinding micro-assay (RBA) for measuring IAA. Our aim was to replace RBA with a novel non-radioactive IAA Luciferase Immuno Precipitation System (LIPS) assay with improved performance. We developed (pro)insulin antigens with alternative placements of a NanoLuc (TM) luciferase reporter (NLuc). Performance in LIPS was evaluated by testing sera from new onset T1D (n = 80), blood donors (n = 123), schoolchildren (n = 186), first-degree relatives (FDRs) from the Bart&#39;s Oxford family study (n = 53) and from the Belgian Diabetes Registry (n = 136), coded sera from the Islet Autoantibody Standardization Program (IASP) (T1D n = 50, blood donors n = 90). IAA LIPS based on B chain-NLuc proinsulin or B chain-NLuc insulin, in which NLuc was fused at the C-terminus of the insulin B chain, required only 2 mu L of serum and a short incubation time, showed high concordance with RBA (Spearman r = 0.866 and 0.833, respectively), high assay performance (B chain-NLuc proinsulin ROC-AUC = 0.894 and B chain-NLuc insulin ROC-AUC = 0.916), and an adjusted sensitivity at 95% specificity ranking on par with the best assays submitted to the two most recent IASP workshops. In FDRs, the IAA LIPS showed improved discrimination of progressors to T1D compared to RBA. We established a novel high-performance non-radioactive IAA LIPS that might replace the current gold standard RBA and find wide application in the study of the IAA response in T1D

Belgian rare diseases plan in clinical pathology : identification of key biochemical diagnostic tests and establishment of reference laboratories and financing conditions

BackgroundOne objective of the Belgian Rare Diseases plan is to improve patients' management using phenotypic tests and, more specifically, the access to those tests by identifying the biochemical analyses used for rare diseases, developing new financing conditions and establishing reference laboratories.MethodsA feasibility study was performed from May 2015 until August 2016 in order to select the financeable biochemical analyses, and, among them, those that should be performed by reference laboratories. This selection was based on an inventory of analyses used for rare diseases and a survey addressed to the Belgian laboratories of clinical pathology (investigating the annual analytical costs, volumes, turnaround times and the tests unavailable in Belgium and outsourced abroad). A proposal of financeable analyses, financing modalities, reference laboratories' scope and budget estimation was developed and submitted to the Belgian healthcare authorities. After its approval in December 2016, the implementation phase took place from January 2017 until December 2019.ResultsIn 2019, new reimbursement conditions have been published for 46 analyses and eighteen reference laboratories have been recognized. Collaborations have also been developed with 5 foreign laboratories in order to organize the outsourcing and financing of 9 analyses unavailable in Belgium.ConclusionsIn the context of clinical pathology and rare diseases, this initiative enabled to identify unreimbursed analyses and to meet the most crucial financial needs. It also contributed to improve patients' management by establishing Belgian reference laboratories and foreign referral laboratories for highly-specific analyses and a permanent surveillance, quality and financing framework for those tests

Personality and self-esteem in emerging adults with Type 1 diabetes

Objective. The present study examined (1) mean-level differences in self-esteem and Big Five personality traits between individuals with and without diabetes; and (2) demographic, clinical, and psychological correlates of patients’ self-esteem and Big Five. Research design and methods. A total of 478 emerging adults with type 1 diabetes (18-35 years old) were selected from the Belgian Diabetes Registry and completed questionnaires on personality, self-esteem, and diabetes-related distress. The control group consisted of 341 healthy participants who were matched (1:1) on sex and age with the patient group. Results. First, mean-level differences between patients and controls differed according to patients’ sex and illness duration. Women with diabetes reported lower self-esteem and were less extraverted and emotionally stable as compared to female controls. In contrast, men with diabetes reported higher self-esteem and were more agreeable but less emotionally stable as compared to male controls. Furthermore, whereas both patients with shorter and longer illness duration were less extraverted and emotionally stable as compared to controls, only patients with longer illness duration reported heightened agreeableness. Second, self-esteem and Big Five were found to relate to patients’ sex and (to a lesser extent) age and illness duration. Finally, patients reporting elevated diabetes-related distress reported lower self-esteem, and were less agreeable and emotionally stable as compared to patients not reporting such distress. Conclusions. Patients’ personality and self-esteem might be important targets for future prevention and intervention efforts. The present findings can assist healthcare professionals in identifying those patients who might benefit the most from such programs.publisher: Elsevier articletitle: Personality and self-esteem in emerging adults with Type 1 diabetes journaltitle: Journal of Psychosomatic Research articlelink: http://dx.doi.org/10.1016/j.jpsychores.2013.11.015 content_type: article copyright: Copyright © 2013 Elsevier Inc. All rights reserved.status: publishe

Self-esteem and illness self-concept in emerging adults with Type 1 diabetes: Long-term associations with problem areas in diabetes

This long-term prospective study examined whether illness self-concept (or the degree to which chronic illness becomes integrated in the self) mediated the pathway from self-esteem to problem areas in diabetes in emerging adults with Type 1 diabetes. Having a central illness self-concept (i.e. feeling overwhelmed by diabetes) was found to relate to lower self-esteem, and more treatment, food, emotional, and social support problems. Furthermore, path analyses indicated that self-esteem was negatively related to both levels and relative changes in these problem areas in diabetes over a period of 5 years. Illness self-concept fully mediated these associations