Clinical and Analytical Impact of Moving from Jaffe to Enzymatic Serum Creatinine Methodology

2020 ◽  
Vol 5 (4) ◽  
pp. 631-642
Author(s):  
Neil R Syme ◽  
Kathryn Stevens ◽  
Catherine Stirling ◽  
Donald C McMillan ◽  
Dinesh Talwar

Abstract Background Identification and monitoring of chronic kidney disease (CKD) requires accurate quantification of serum creatinine. The poor specificity of Jaffe creatinine methods is well documented, and guidelines recommend enzymatic methodology. We describe our experience of moving from Jaffe to enzymatic creatinine methodology. We present comparison of >5000 paired Jaffe and enzymatic creatinine results, examine interferences, and attempt to assess clinical consequences of changing methodology. Methods Overall, 5303 serum samples received for routine creatinine measurement were analyzed using Jaffe and enzymatic methods with an Abbott Architect autoanalyzer. Associated results for glucose, total bilirubin, triglycerides, total protein, and hemolytic, icteric, and lipemic indexes were extracted from the laboratory database. CKD staging was estimated for each sample to assess potential clinical effects. Results The methods correlated well (r = 0.996) and showed good agreement (Passing-Bablok fit, y = 0.935x + 0.074). Paired analysis, however, showed significant differences (P < 0.001), and approximately 20% of results differed by more than ±10%. Multivariate analysis demonstrated independent associations between difference in creatinine results, glucose (P < 0.0001), and hemolytic index (P = 0.009). Glucose demonstrated positive interference in the Jaffe method, and hemolysis produced negative interference in the enzymatic method. Little or no association was observed with other analytes. CKD staging differed in 4% of samples. Conclusions Differences between Jaffe and enzymatic serum creatinine results exceed the recommended 5% target for a significant proportion of samples, particularly at concentrations <1.13 mg/dL (100 µmol/L). Both glucose and hemolysis contribute to the variance in results. Although the clinical impact of these differences seems small, laboratories should continue moving toward enzymatic creatinine estimation to ensure the best estimate of renal function.

2020 ◽  
Vol 45 (5) ◽  
pp. 491-498
Author(s):  
Fatih Yesildal ◽  
Ferruh Kemal Isman

AbstractObjectiveCOVID-19 pandemia still continues to threaten the whole world. High dose ascorbic acid (AA) infusion is a choice of treatment and its efficiency is still being investigated. AA interferes with many clinical chemistry tests. However, data about the interference of high concentrations of AA is not sufficient. In this study, we aimed to investigate the interference of AA at high concentrations on commonly used chemistry assays.Materials and MethodsSerum samples at AA concentrations of 200, 150, 100, 75, 50, 25, 10, 5, 2 and 0 mg/dL were prepared by using the stock solution of 15000 mg/dL AA. Each sample was analyzed by using the most common 30 chemistry tests (Abbott Architect C8000, Illinois, USA) and a POCT glucometer (STANDARD GlucoNavii, Gyeonggi-do, Republic of Korea).ResultsCreatinine, sodium and glucose (POCT) tests were found to be positively interfered by increasing AA concentrations; while direct bilirubin, lipase, UIBC, triglyceride, total cholesterol, HDL/LDL cholesterol tests were negatively interfered. Absolute interference (%) increased as the AA concentration increased.ConclusionThis is the largest and first study to investigate the interference of high dose AA, which is used in severe COVID-19 patients nowadays. Manufacturers and clinicians should be aware of the possibility of aberrant results due to high dose AA infusion. Clinicians should not forget to consult a laboratory specialist, since he is the only person to monitor the reactions in all assays, and know the technical subjects like interferences, assay method specifications. This issue is very important for correct decision-making and interpretation of the data-mining studies accurately and efficiently.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Yael D. Lewis ◽  
Lucy Gallop ◽  
Iain C. Campbell ◽  
Ulrike Schmidt

Abstract Background Most psychiatric disorders have their onset in childhood or adolescence, and if not fully treated have the potential for causing life-long psycho-social and physical sequelae. Effective psychotherapeutic and medication treatments exist, but a significant proportion of children and young people do not make a full recovery. Thus, novel, safe, brain-based alternatives or adjuncts to conventional treatments are needed. Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are non-invasive brain stimulation (NIBS) techniques which have shown clinical benefits in adult psychiatric conditions. However, in children and young people their efficacy is not well established. The objective of this study will be to systematically evaluate the evidence on clinical effects of NIBS in children and young people with psychiatric disorders, assessing disorder-specific symptoms, mood and neurocognitive functions. Methods We designed and registered a study protocol for a systematic review. We will include randomised and non-randomised controlled trials and observational studies (e.g. cohort, case-control, case series) assessing the effects of NIBS in children and young people (aged ≤ 24 years old) for psychiatric disorders. The primary outcome will be reduction of disorder-specific symptoms. Secondary outcomes will include effects on mood and cognition. A comprehensive search from database inception onwards will be conducted in MEDLINE, EMBASE and PsycINFO. Grey literature will be identified through searching multiple clinical trial registries. Two reviewers will independently screen all citations, full-text articles and abstract data. The methodological quality of the studies will be appraised using appropriate tools. We will provide a narrative synthesis of the evidence and according to heterogeneity will conduct an appropriate meta-analysis. Additional analyses will be conducted to explore the potential sources of heterogeneity. Discussion This systematic review will provide a broad and comprehensive evaluation of the evidence on clinical effects of NIBS in children and young people with psychiatric disorders. Our findings will be reported according to the PRISMA guidelines and will be of interest to multiple audiences (including patients, researchers, healthcare professionals and policy-makers). Results will be published in a peer-reviewed journal. Systematic review registration PROSPERO CRD42019158957


2021 ◽  
Vol 05 (01) ◽  
pp. 007-011
Author(s):  
Shaheen Afsal ◽  
K. Sujani ◽  
Shashank Viswanathan ◽  
Akshay Bhati ◽  
Harish BR ◽  
...  

AbstractCardiovascular disease (CVD) is a major cause for a significant proportion of all deaths and disability worldwide. Postoperative renal dysfunction following cardiac surgery is not an uncommon complication of cardiac surgery, which has serious implications with regard to morbidity, mortality, financial expenditure, and resource utilization. This study was performed to compare outcomes of patients with preoperative renal dysfunction with those having normal renal function undergoing off-pump coronary artery bypass grafting (OPCABG). Patients were divided into two categories, depending on their preoperative serum creatinine and glomerular filtration rate (GFR). The preoperative renal dysfunction was defined as serum creatinine >1.3 mg/dL and/or estimated GFR (eGFR) of <60 mL/min/1.73 m2. The category A patients had normal renal function defined as serum creatinine ≤1.3 mg/dL and/or eGFR of ≥60 mL/min/1.73 m2 while the category B patients had preoperative renal dysfunction that did not necessitate renal dialysis. Blood samples were collected from both category patients for serum creatinine prior to surgery, following surgery, on postoperative days 1, 2, 3, 4, 5, and on the day of discharge. The occurrence of acute kidney injury (AKI) was defined as an increase in the serum creatinine levels of ≥0.3 mg/dL within 48 hours or an increase of ≥1.5 above baseline known or presumed to have occurred within the previous 7 days based on Kidney Disease Improving Global Outcomes criteria. This study demonstrated that there was worsening of renal function in 7.4% of patients with normal renal function and 10.74% of patients with renal dysfunction that was not statistically different. Based on the results, we conclude that preoperative renal dysfunction may be a contributing predictor of AKI following OPCABG, and we recommend that the patients with more severe renal dysfunction with eGFR of 45–60 mL/min should be studied to demonstrate this hypothesis.


Author(s):  
Mary Kathryn Bohn ◽  
Siobhan Wilson ◽  
Alexandra Hall ◽  
Khosrow Adeli

Abstract Objectives The Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) has developed an extensive database of reference intervals (RIs) for several biomarkers on various analytical systems. In this study, pediatric RIs were verified for key immunoassays on the Abbott Alinity system based on the analysis of healthy children samples and comparison to comprehensive RIs previously established for Abbott ARCHITECT assays. Methods Analytical performance of Alinity immunoassays was first assessed. Subsequently, 100 serum samples from healthy children recruited with informed consent were analyzed for 16 Alinity immunoassays. The percentage of test results falling within published CALIPER ARCHITECT reference and confidence limits was determined. If ≥ 90% of test results fell within the confidence limits, they were considered verified based on CLSI guidelines. If <90% of test results fell within the confidence limits, additional samples were analyzed and new Alinity RIs were established. Results Of the 16 immunoassays assessed, 13 met the criteria for verification with test results from ≥ 90% of healthy serum samples falling within the published ARCHITECT confidence limits. New CALIPER RIs were established for free thyroxine and prolactin on the Alinity system. Estradiol required special considerations in early life. Conclusions Our data demonstrate excellent concordance between ARCHITECT and Alinity immunoassays, as well as the robustness of previously established CALIPER RIs for most immunoassays, eliminating the need for de novo RI studies for most parameters. Availability of pediatric RIs for immunoassays on the Alinity system will assist clinical laboratories using this new platform and contribute to improved clinical decision-making.


2016 ◽  
Vol 15 (5) ◽  
pp. 1077 ◽  
Author(s):  
Zhen-Hong Pan ◽  
Yan-Xuan Zhang ◽  
Jun Fang ◽  
Qing-Shan Qu ◽  
Xin Jiang ◽  
...  

2019 ◽  
Vol 3 (6) ◽  
pp. 936-942 ◽  
Author(s):  
Jayson V Pagaduan ◽  
Estella Tam ◽  
Sridevi Devaraj

Abstract Background Procalcitonin (PCT) is an emerging biomarker for detecting sepsis. Recently, the US Food and Drug Administration cleared the expanded use of this biomarker for guiding clinicians regarding antibiotic treatment. To our knowledge, there are no published method validations for the Abbott Architect PCT assay. This article will discuss the process of method validation of the B·R·A·H·M·S PCT assay on the Abbott Architect platform. Methods We studied the precision, accuracy, and linearity of the Architect method following the guidance of the Clinical and Laboratory Standards Institute EP5-A2 document. Furthermore, we also tested the impact of major sources of interference from hemolysate, lipoproteins, and bilirubin. To validate the Architect method, we compared patients' serum PCT measurements with our previously established Mini VIDAS (bioMerieux) PCT assay. Results Statistical analysis showed that the 2 assays have good correlation (r &gt; 0.99), slope of 1.023, and intercept of −0.760. The calculated bias is −7.435%. The Architect method showed good precision with %CV &lt; 3.5% for both interassay and intraassay compared with %CV &lt; 6.5% for Mini VIDAS, which was previously determined at our institution. No bias &gt;10% was observed with the Architect method when pooled serum samples were spiked with interferants. The turnaround time for both platforms was the same (20 min); however, in contrast with Mini VIDAS, the Architect system has automated pipetting of samples and can perform multiple assays simultaneously. Conclusion These results showed that the Architect B·R·A·H·M·S PCT assay has analytical characteristics conducive for diagnostic use in clinical laboratories. Our method validation report will be beneficial for other institutions to adapt this assay on existing Abbott Architect i1000 immunoassay analyzers.


2022 ◽  
Vol 23 (2) ◽  
pp. 673
Author(s):  
Vittoria Favero ◽  
Arianna Cremaschi ◽  
Chiara Parazzoli ◽  
Alberto Falchetti ◽  
Agostino Gaudio ◽  
...  

Mild hypercortisolism is defined as biochemical evidence of abnormal cortisol secretion without the classical detectable manifestations of overt Cushing’s syndrome and, above all, lacking catabolic characteristics such as central muscle weakness, adipose tissue redistribution, skin fragility and unusual infections. Mild hypercortisolism is frequently discovered in patients with adrenal incidentalomas, with a prevalence ranging between 5 and 50%. This high variability is mainly due to the different criteria used for defining this condition. This subtle cortisol excess has also been described in patients with incidentally discovered pituitary tumors with an estimated prevalence of 5%. To date, the mechanisms responsible for the pathogenesis of mild hypercortisolism of pituitary origin are still not well clarified. At variance, recent advances have been made in understanding the genetic background of bilateral and unilateral adrenal adenomas causing mild hypercortisolism. Some recent data suggest that the clinical effects of glucocorticoid (GC) exposure on peripheral tissues are determined not only by the amount of the adrenal GC production but also by the peripheral GC metabolism and by the GC sensitivity. Indeed, in subjects with normal cortisol secretion, the combined estimate of cortisol secretion, cortisone-to-cortisol peripheral activation by the 11 beta-hydroxysteroid dehydrogenase enzyme and GC receptor sensitizing variants have been suggested to be associated with the presence of hypertension, diabetes and bone fragility, which are three well-known consequences of hypercortisolism. This review focuses on the pathophysiologic mechanism underlying both the different sources of mild hypercortisolism and their clinical consequences (bone fragility, arterial hypertension, subclinical atherosclerosis, cardiovascular remodeling, dyslipidemia, glucose metabolism impairment, visceral adiposity, infections, muscle damage, mood disorders and coagulation).


2020 ◽  
Author(s):  
Beatriz Araujo Oliveira ◽  
Lea Campos de Oliveira ◽  
Franciane Mendes de Oliveira ◽  
Geovana Maria Pereira ◽  
Regina Maia de Souza ◽  
...  

AbstractBackgroundCOVID-19 disease (Coronavirus disease 2019) caused by SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) is widespread worldwide, affecting more than 11 million people globally (July 6th, 2020). Diagnostic techniques have been studied in order to contain the pandemic. Immunochromatographic (IC) assays are feasible and low cost alternative for monitoring the spread of COVID-19 in the population.MethodsHere we evaluate the sensitivity and specificity of eleven different immunochromatographic tests in 98 serum samples from confirmed cases of COVID-19 through RT-PCR and 100 negative serum samples from blood donors collected in February 2019. Considering the endemic situation of Dengue in Brazil, we also evaluated the cross-reactivity with Dengue using 20 serum samples from patients with confirmed diagnosis for Dengue collected in early 2019 through four different tests.ResultsOur results demonstrated agreement between immunochromatographic assays and RT-PCR, especially after 10 days since the onset of symptoms. The evaluation of IgG and IgM antibodies combined demonstrated a strong level of agreement (0.85) of IC assays and RT-PCR. It was observed cross-reactivity between Dengue and COVID-19 using four different IC assays for COVID-19 diagnosis. The specificity of IC assays to detected COVID-19 IgM antibodies using Dengue serum samples varied from 80% to 85%; the specificity of IgG detection was 100% and total antibody was 95%.ConclusionsWe found high sensitivity, specificity and good agreement of IC assays, especially after 10 days onset of symptoms. However, we detected cross-reactivity between Dengue and COVID-19 mainly with IgM antibodies demonstrating the need for better studies about diagnostic techniques for these diseases.HighlightsImmunochromatographic assays demonstrated high sensitivity and specificity and good agreement with the gold-standard RT-PCR;Increase in sensitivity and specificity of assays using samples collected after the 10th day of symptoms;Cross-reaction with Dengue serology in evaluation of IgM.


Author(s):  
Joanne Adaway ◽  
Brian Keevil ◽  
Annmarie Miller ◽  
Phillip J Monaghan ◽  
Nicola Merrett ◽  
...  

Objective Sex hormone-binding globulin (SHBG) is a glycoprotein which binds hormones such as testosterone. Around 97% of circulating testosterone is bound to SHBG or albumin and is therefore biologically unavailable; 2–3% of testosterone is free. Free testosterone is very technically challenging to quantify; in order to circumvent this problem, equations using testosterone and SHBG are used to estimate free testosterone. We decided to determine the effect of using different SHBG immunoassays on calculated free testosterone results. Design Anonymized surplus serum samples were analysed for SHBG on four different immunoassay platforms (Abbott Architect, Roche, Beckman and Siemens). The SHBG results were used to generate a Vermeulen calculated free testosterone. Results Beckman Access and Siemens Centaur both gave results close to the overall mean. Roche gave the highest SHBG concentrations with Abbott Architect producing the lowest results. Abbott Architect gave the highest calculated free testosterone results, followed by Beckman. Roche gave the lowest results. Sixty-five per cent of male samples had low calculated free testosterone and 27.5% of the females had high calculated free testosterone using the SHBG from the Abbott assay compared with 69% low male calculated free testosterone and 20% high female calculated free testosterone with the Roche assay. Conclusion Our results have shown significant differences in SHBG results produced by different analysers and subsequently the calculated free testosterone, which may affect result interpretation if method-specific reference ranges for calculated free testosterone are not used. Care should be taken to ensure reference ranges are appropriate for the analyser used to avoid misdiagnosis of hypo or hyperandrogenism, and ensure patients get the most appropriate treatment.


Sign in / Sign up

Export Citation Format

Share Document