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Introduction: Cardiovascular mortality is significantly increased in kidney failure with replacement therapy (KFRT) patients, which is partly mediated by enhanced vascular calcification. Magnesium appears to have anticalcifying capabilities, and hypomagnesemia has been associated with increased mortality in KFRT patients. Ionized magnesium represents the biologically and physiologically active form. As serum ionized magnesium (Mgion) is difficult to assess in clinical routine estimating equations derived from routinely assessed laboratory parameters could facilitate medical treatment. Methods: We developed equations to estimate serum Mgion using linear regression analysis in 191 hemodialysis (HD) patients. Reference test was measured ionized magnesium (Mgion). As index tests, we chose estimated Mgion using total magnesium (Mgtot) and other laboratory and demographic variable candidates. Equations were internally validated, using 749 subsequent Mgion measurements. Findings The median patient age was 65 years, 67.5% of the patients were male. Median (interquartile range [IQR]) measured Mgion was 0.64 [0.57, 0.72] mmol/L, 11 (6%) patients were hypo‐ (i.e., <0.45 mmol/L) and 127 (66%) were hypermagnesemic (>0.60 mmol/L). The final equation at the end of the development process included Mgtot, serum ionized, and total calcium concentrations. In the validation dataset, bias (i.e., median difference between measured and estimated Mgion, −0.017 [−0.020, −0.014] mmol/L) and precision (i.e., IQR of bias 0.043 [0.039, 0.047] mmol/L) were small, 90% [88, 93] of estimated values were ±10% of measured values. The equation detected normomagnesemia with overall good diagnostic accuracy (area under the receiver‐operating curve 0.91 [0.89, 0.93]). Discussion Mgion can be estimated from equations containing routinely assessed laboratory variables with high accuracy and good overall performance. These equations might simplify the assessment of ionized magnesium levels in the individual hemodialysis patients and help the treating physician to guide the overall treatment. [ABSTRACT FROM AUTHOR]

Legal regulations and guidelines such as the Guidelines of the German Medical Association for the Quality Assurance of Laboratory Medical Examinations (Rili-BAEK) and ISO 15189 apply to electronic laboratory reports. However, many laboratories struggle with practical implementation of these regulations and guidelines. Laboratory and legal experts analyse the relevant guidelines and provide checklists and practical recommendations for implementation. Laboratories have less control over the display of electronic laboratory reports than over paper documents. However, an electronic report alone is legally sufficient and need not be accompanied by a paper copy. Rili-BAEK and ISO 15189 stipulate a set of minimum information in every report. The laboratory must verify that reports are transmitted and displayed correctly. To help laboratories do so, agreements between laboratories and the report recipients can clarify responsibilities. Electronic laboratory reports can improve patient care, but laboratories need to verify their quality. Towards this end, Rili-BAEK and ISO 15189 set out helpful provisions. [ABSTRACT FROM AUTHOR]

In recent years, there has been renewed interest in the "old" average of normals concept, now generally referred to as moving average quality control (MA QC) or patient-based real-time quality control (PBRTQC). However, there are some controversies regarding PBRTQC which this review aims to address while also indicating the current status of PBRTQC. This review gives the background of certain newly described optimization and validation methods. It also indicates how QC plans incorporating PBRTQC can be designed for greater effectiveness and/or (cost) efficiency. Furthermore, it discusses controversies regarding the complexity of obtaining PBRTQC settings, the replacement of iQC, and software functionality requirements. Finally, it presents evidence of the added value and practicability of PBRTQC. Recent developments in, and availability of, simulation methods to optimize and validate laboratory-specific PBRTQC procedures have enabled medical laboratories to implement PBRTQC in their daily practice. Furthermore, these methods have made it possible to demonstrate the practicability and added value of PBRTQC by means of two prospective "clinical" studies and other investigations. Although internal QC will remain an essential part of any QC plan, applying PBRTQC can now significantly improve its performance and (cost) efficiency. [ABSTRACT FROM AUTHOR]

Therapeutic drug monitoring (TDM) plays a crucial role in personalized medicine. It helps clinicians to tailor drug dosage for optimized therapy through understanding the underlying complex pharmacokinetics and pharmacodynamics. Conventional, non-continuous TDM fails to provide real-time information, which is particularly important for the initial phase of immunosuppressant therapy, e.g., with cyclosporine (CsA) and mycophenolic acid (MPA). We analyzed the time course over 8 h of total and free of immunosuppressive drug (CsA and MPA) concentrations measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in 16 kidney transplant patients. Besides repeated blood sampling, intravenous microdialysis was used for continuous sampling. Free drug concentrations were determined from ultracentrifuged EDTA-plasma (UC) and compared with the drug concentrations in the respective microdialysate (µD). µDs were additionally analyzed for free CsA using a novel immunosensor chip integrated into a fluorescence detection platform. The potential of microdialysis coupled with an optical immunosensor for the TDM of immunosuppressants was assessed. Using LC-MS/MS, the free concentrations of CsA (fCsA) and MPA (fMPA) were detectable and the time courses of total and free CsA comparable. fCsA and fMPA and area-under-the-curves (AUCs) in µDs correlated well with those determined in UCs (r≥0.79 and r≥0.88, respectively). Moreover, fCsA in µDs measured with the immunosensor correlated clearly with those determined by LC-MS/MS (r=0.82). The new microdialysis-supported immunosensor allows real-time analysis of immunosuppressants and tailor-made dosing according to the AUC concept. It readily lends itself to future applications as minimally invasive and continuous near-patient TDM. [ABSTRACT FROM AUTHOR]

The quest to use patient results as quality control for routine clinical chemistry testing has long been driven by issues of the unavailability and cost of suitable quality control material and the matrix effects of synthetic material. Hematology laboratories were early adopters of average of normals techniques, primarily because of the difficulty in acquiring appropriate, stable quality control material, while in the chemistry laboratories, the perceived advantages and availability of synthetic material outweighed the disadvantages. However, the increasing volume of testing in clinical chemistry plus the capability of computer systems to deal with large and complex calculations has now made the use of patient-based quality control algorithms feasible. The desire to use patient-based quality control is also driven by increasing awareness that common quality control rules and frequency of analysis may fail to detect clinically significant assay biases. The non-commutability of quality control material has also become a problem as laboratories seek to harmonize results across regions and indeed globally. This review describes the history of patient-based quality control in clinical chemistry, summarizes the various approaches that can be implemented by laboratory professionals, and discusses how patient-based quality control can be integrated with traditional quality control techniques. [ABSTRACT FROM AUTHOR]

Patient-based real-time quality control (PBRTQC) is a laboratory tool for monitoring the performance of the testing process. It includes well-established procedures like Bull's algorithm, average of nomals, moving median, moving average (MA) and exponentially (weighted) MAs. Following the setup and optimization processes, a key step prior to the routine implementation of PBRTQC is the verification and documentation of the performance of the PBRTQC as part of the laboratory quality system. This verification process should provide a realistic representation of the performance of the PBRTQC in the environment it is being implemented in, to allow proper risk assessment by laboratory practitioners. This document focuses on the recommendation on performance verification of PBRTQC prior to implementation. [ABSTRACT FROM AUTHOR]

The article offers information on The point-of-care testing (POCT) working group POCT of the German Society for Clinical Chemistry and Laboratory Medicine (DGKL) organized the 4th Munich POCT Symposium on the subject of "POCT at the Interface of Emerging Technologies and New Clinical Applications".

Point-of-care testing (POCT) has been an essential service in hospitals for many years with a main focus on reliability, classical laboratory quality criteria and easy handling. Hospital information technology (IT) security regulations, however, have not yet been adapted to the specificities of POCT. Following the POCT Symposium in Munich, the "1st Round Table POCT-IT-Security Meeting" held in October 2019 in Cologne addressed these issues and managed to establish first consensus results in the essential fields of user, data and update management, as well as network connections and user-friendliness. First practical steps include optimizing the user management by connection to a directory service and definition of access control (including emergency authorization). Patient data economy on analyzers in combination with data and data transmission encryption as well as technically secure communication protocols are relevant steps in the fields of data management and network connections. An update management needs to be contractually defined for remote services and generally includes testing in a protocol-based scenario. Providing an organizational structure for POCT-IT security is a necessary prerequisite, as are continuous training and awareness for this topic with a strong focus on usability. [ABSTRACT FROM AUTHOR]

Background: Point-of-care tests (POCT) measure analytes close to the patients and are a complementary supplement to the test menu of medical laboratories. However, the involvement of many different stakeholders makes it challenging to ensure reliable results. Methods: In a survey, we asked experienced POCT users how they control their total POCT process and what factors they consider essential for success. Results were verified in four in-depth interviews. Results: Overall, 73 German participants from various medical disciplines completed the survey. All but one participant regarded operator training as important but only half of the participants' institutions conducted operator training on a regular basis. Participants often requested e-learning, but face-to-face teaching is still preferred. Twenty-one percent of participants already used e-learning and reported mixed satisfaction. Fifty-five percent of the participants never refer to the quality management manual. Instead, 94% stated that if a POCT error arises a contact person for POCT is always available at their workplace. The majority of participants think that external and, in particular, internal quality controls are important for POCT. Only a few difficulties for performing quality control such as "temporal expenditure" and "lack of information about the importance of internal quality control" were commonly mentioned. For future developments, participants expect evolution and improvements especially with regard to "measurement quality and reliability". The answers of the experts in the in-depth interviews largely corresponded with the participants of the survey. Conclusions: The importance of operator training is well established and confirmed in this work. How to conduct this training is less certain, but the answers in this survey suggest some form of blended learning with e-learning and practical elements. The discrepancy between the high importance that guidelines and other normative documents place on written information and their low practical usage was striking. [ABSTRACT FROM AUTHOR]

Background: Persistent antiphospholipid antibodies (aPL) constitute the serological hallmark of the antiphospholipid syndrome (APS). Recently, various new assay technologies for the detection of aPL better suited to multiplex reaction environments than ELISAs emerged. We evaluated the diagnostic performance of such a novel line immunoassay (LIA) for the simultaneous detection of 10 different aPL. Methods: Fifty-three APS patients and 34 healthy controls were investigated for criteria (antibodies against cardiolipin [aCL], β2-glycoprotein I [aβ2-GPI]) and non-criteria aPL (antibodies against phosphatidic acid [aPA], phosphatidyl-choline [aPC], -ethanolamine [aPE], -glycerol [aPG], -inositol [aPI], -serine [aPS], annexin V [aAnnV], prothrombin [aPT]) IgG and IgM by LIA. Criteria aPL were additionally determined with the established Alegria (ALE), AcuStar (ACU), UniCap (UNI), and AESKULISA (AES) systems and non-criteria aPL with the AES system. Diagnostic performance was evaluated with a gold standard for criteria aPL derived from the results of the four established assays via latent class analysis and with the clinical diagnosis as gold standard for non-criteria aPL. Results: Assay performance of the LIA for criteria aPL was comparable to that of ALE, ACU, UNI, and AES. For non-criteria aPL, sensitivities of the LIA for aPA-, aPI-, aPS-IgG and aPA-IgM were significantly higher and for aPC-, aPE-, aAnnV-IgG and aPC- and aPE-IgM significantly lower than AES. Specificities did not differ significantly. Conclusions: The LIA constitutes a valuable diagnostic tool for aPL profiling. It offers increased sensitivity for the detection of aPL against anionic phospholipids. In contrast, ELISAs exhibit strengths for the sensitive detection of aPL against neutral phospholipids. [ABSTRACT FROM AUTHOR]

Background: Terminologies facilitate data exchange and enable laboratories to assist in patient care even if complex treatment pathways involve multiple stakeholders. This paper examines the three common terminologies Nomenclature for Properties and Units (NPU), Logical Observation Identifiers Names and Codes (LOINC), and SNOMED Clinical Terms (SNOMED CT). Methods: The potential of each terminology to encode five exemplary laboratory results is assessed. The terminologies are evaluated according to scope, correctness, formal representations, and ease of use. Results: NPU is based on metrological concepts with strict rules regarding the coding of the measurand and the result value. Clinically equivalent results are regularly mapped to the same code but there is little support to differentiate results from non-standardized measurements. LOINC encodes analyses as offered by the laboratory. Its large number of entries allows different mappings for the same analysis. SNOMED CT contains few analyses natively, but its formal composition mechanism allows representing measurements by post-coordinated expressions that are equivalent to LOINC codes. SNOMED CT's strength lies in its support of many non-numerical result values. Implicit code hierarchies exist in NPU and LOINC. SNOMED CT has explicit, elaborate axioms that elucidate the meaning of its content. Its complexity and its license conditions, however, impede a more widespread use. Interpretive comments, a crucial part of laboratory results, are still difficult to encode with any of the terminologies. Conclusions: All three terminologies have distinct potentials and limitations, but the approximation of SNOMED CT and LOINC suggests using them together. Terminologies need to be expanded to also cover interpretive comments. [ABSTRACT FROM AUTHOR]

Health systems worldwide struggle to provide the optimal treatment amid the rapid pace of scientific progress and frequent structural changes. Learning health systems (LHS) that continuously analyze their data to generate evidence and to enable informed decisions have been proposed as a possible solution. This paper investigates the involvement of laboratory medicine in LHS and evaluates relevant systems according to their scope, enabling technologies, architecture for evidence generation, data-action latency, and social aspects. While laboratory medicine provides a central source of information in many large-scale LHS, there are also systems with a particular focus on laboratories. For example, external quality assessments are performed by sending samples with known quantities to laboratories worldwide to verify their analytical methods. This data are also analyzed for other purposes, such as post-market surveillance of devices. These schemes have operated successfully over several decades. Newer, innovative tools harvest the possibilities of wearable devices and increased connectivity. LHS in laboratory medicine need to be recognized and incorporated into systems of systems to generate better evidence. Further research on the roles of other stakeholders will identify opportunities and obstacles for building and maintaining successful LHS. [ABSTRACT FROM AUTHOR]

Background: Determination of blood glucose concentration is one of the most important measurements in clinical chemistry worldwide. Analyzers in central laboratories (CL) and point-of-care tests (POCT) are both frequently used. In Germany, regular participation in external quality assessment (EQA) schemes is mandatory for laboratories performing glucose testing. Methods: Glucose testing data from the two German EQAs "Reference Institute for Bioanalytics" (RfB) and "INSTAND -- Gesellschaft zur Förderung der Qualitätssicherung in medizinischen Laboratorien" (Instand) were analyzed from 2012 to 2016. Multivariable odds ratios (OR) for the probability to reach a "good" result were calculated. Imprecision and bias were determined and clinical risk of measurement errors estimated. Results: The device employed was the most important variable required for a "good" performance in all EQAs. Additional participation in an EQA for CL automated analyzers improved performance in POCT EQAs. The reciprocal effect was less pronounced. New participants performed worse than experienced participants especially in CL EQAs. Imprecision was generally smaller for CL, but some POCT devices reached a comparable performance. Large lot-to-lot differences occurred in over 10% of analyzed cases. We propose the "bias budget" as a new metric to express the maximum allowable bias that still carries acceptable medical risk. Bias budgets were smallest and clinical risks of errors greatest in the low range of measurement 60-115 mg/dL (3.3-6.4 mmol/L) for most devices. Conclusions: EQAs help to maintain high analytical performances. They generate important data that serve as the foundation for learning and improvement in the laboratory healthcare system. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Laboratory Medicine / Laboratoriums Medizin is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Laboratory Medicine / Laboratoriums Medizin is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Method evaluation of new assays for the detection of antiphospholipid antibodies (aPL) such as anti-cardiolipin (aCL) or anti-β2-glycoprotein I (aβ2-GPI) is challenging, as no internationally accepted reference material is available yet. Besides a lack of standardization, unacceptable inter-laboratory comparability of established tests is regularly observed. Owing to the absence of a commonly accepted reference standard, the evaluation of two research surface plasmon resonance (SPR) biosensor assays was performed using statistical methods from latent class analysis (LCA). Methods: aCL and aβ2-GPI IgG and IgM were measured in sera from 63 antiphospholipid syndrome patients, fulfilling the Sydney criteria, and in 34 healthy controls with four commercial assays. LCA was performed on the results and sera were assigned to the antibody-positive or antibody- negative group. Sera were subsequently evaluated in the SPR assays for aCL and aβ2-GPI. Optimal cutoffs and diagnostic performances of the research systems were established employing the LCA-derived gold standard. Results: With area under the curve results of 0.96 and 0.89 for the detection of aCL and aβ2-GPI, the research SPR assays discriminated well between antibody-positive and antibody-negative sera. Their sensitivities and specificities were comparable to the investigated commercial immunoassays. Conclusions: SPR assays are a suitable tool for the detection of aCL and aβ2-GPI with diagnostic performances not different from currently available commercial tests. LCA enabled the calculation of sensitivities and specificities for aPL assays in absence of a reference standard. [ABSTRACT FROM AUTHOR]

An introduction to articles in the issue is presented on topics including a set of ICT tools that is used in Switzerland to render laboratory data interoperable, the process of implementing the Australian electronic health record, and some of the challenges of new diagnostic tests that produce so much data.

Background: In health care, exchange of data is becoming increasingly important. However, it is still unclear how to interpret measurements of the same parameter from diverse data sources. In clinical chemistry point-of-care testing (POCT), e.g. for blood glucose, complements the analytical spectrum of central laboratories. Available data from "central laboratory", "professional POCT" and "non-professional" blood glucose measurements can be used to realistically simulate errors in different environments. The ability to classify the disease status or to detect a significant change based on these simulated measurements was assessed in several scenarios. Methods: Patients were simulated with realistic "true values" of blood glucose and a "diseased" or "non-diseased" status. To further simulate a change of blood glucose values, a random difference was created and classified as "significant" or "non-significant". Scientific literature was searched for accuracy and precision of blood glucose measurements in different environments. These values were used to calculate "measured values" from the "true values". In scenarios where only measurements from the same environment were combined the area under the ROC curve (AUC) was used to express classifier performance. Balanced accuracy was used for scenarios with a combination of measurements from different environments. Situations with and without prior knowledge of the data source were simulated separately. Results: AUC for the classification of disease status remained around 0.68 in all scenarios. Median AUCs for the detection of a significant change ranged between 0.89 in the central laboratory and 0.76 in the non-professional environment. For the combination of different measurement environments median balanced accuracies reached 0.63 for the classification of the disease status and differed little between scenarios. Median balanced accuracy to detect a significant change ranged from 0.81 to 0.72. When there was no prior knowledge about the additional data source it could not be used to determine an optimal decision boundary. In these cases, median balanced accuracy was approximately 0.02 lower. Conclusion: These simulations highlight issues that are relevant beyond the combination of blood glucose values. Measurements conducted to help clarify one medical issue are often reused in other contexts. However not all data sources are equally suitable for all analyses. Therefore, when data from laboratory medicine is exchanged, accompanying information that helps to estimate reliability is critically important. [ABSTRACT FROM AUTHOR]

Introduction:This study presents a web-based method and its interface ensuring alignment of all parts of a curriculum map including competencies, objectives, teaching and assessment methods, workload and patient availability. Needs, acceptance and effectiveness are shown through a nine-year study. Methods:After a comprehensive needs assessment, the curriculum map and a web-based interface “Learning Opportunities, Objectives and Outcome Platform” (LOOOP) were developed according to Harden’s conceptual framework of 10-steps for curriculum mapping. The outcome was measured by surveys and results of interdisciplinary MCQ-assessments. The usage rates and functionalities were analysed. Results:The implementation of LOOOP was significantly associated with improved perception of the curriculum structure by teachers and students, quality of defined objectives and their alignment with teaching and assessment, usage by students to prepare examinations and their scores in interdisciplinary MCQ-assessment. Additionally, LOOOP improved the curriculum coordination by faculty, and assisted departments for identifying patient availability for clinical training. Conclusion:LOOOP is well accepted among students and teachers, has positive effect on curriculum development, facilitates effective utilisation of educational resources and improves student’s outcomes. Currently, LOOOP is used in five undergraduate medical curricula including 85,000 mapped learning opportunities (lectures, seminars), 5000 registered users (students, teachers) and 380,000 yearly page-visits. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Laboratory Medicine / Laboratoriums Medizin is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Access to patients is a crucial factor for student-centred medical education. However, increasing numbers of students, teacher shortage, a patient spectrum consisting of rarer diseases, and quicker discharges limit this necessary access, and therefore pose a challenge for curriculum designers. The herein presented algorithm improves access to patients in four steps by using routinely available electronic patient data already during curriculum development. Step I: Learning objectives are mapped to appropriate ICD-10 (International Statistical Classification of Diseases) codes. Step II: It is determined which learning opportunities need to be considered first for patient allocation in order to maximise overall benefit. Step III: Hospital's departments with the highest expertise on respective learning objectives are assessed and selected for teaching. Step IV: Patients of the chosen department that present the best match for a given learning opportunity are assigned to participation. This integrated analysis of learning objectives and existing clinical data during curriculum development is a well-structured method to maximise access to patients. Furthermore, this algorithm identifies learning objectives of a curriculum that do not correspond well to the spectrum of patients of the respective teaching hospital and which should therefore be taught in learning formats without patient contact. [ABSTRACT FROM AUTHOR]

In an increasingly interconnected health care system, laboratory medicine can facilitate diagnosis and treatment of patients effectively. This article describes necessary changes and points to potential challenges on a technical, content, and organizational level. As a technical precondition, electronic laboratory reports have to become machine-readable and interpretable. Terminologies such as Logical Observation Identifiers Names and Codes (LOINC), Nomenclature for Properties and Units (NPU), Unified Code for Units of Measure (UCUM), and SNOMED-CT can lead to the necessary semantic interoperability. Even if only single "atomized" results of the whole report are extracted, the necessary information for correct interpretation must be available. Therefore, interpretive comments, e.g., concerns about an increased measurement uncertainty must be electronically attached to every affected measurement result. Standardization of laboratory analyses with traceable standards and reference materials will enable knowledge transfer and safe interpretation of laboratory analyses from multiple laboratories. In an interconnected health care system, laboratories should strive to transform themselves into a data hub that not only receives samples but also extensive information about the patient. On that basis, they can return measurement results enriched with high-quality interpretive comments tailored to the individual patient and unlock the full potential of laboratory medicine. [ABSTRACT FROM AUTHOR]

The article discusses guideline of the German Medical Association for quality assurance of medical laboratory examinations in the form of the "Peer Review" in addition to the classic audits. It mentions focus on collegial exchange and ultimately improve quality; and also mentions need for quality assurance in laboratory medicine.

This article presents a systematic literature review that expands and updates a previous review on the application of machine learning to laboratory medicine. We used Scopus and PubMed to collect, select and analyse the papers published from 2017 to the present in order to highlight the main studies that have applied machine learning techniques to haematochemical parameters and to review their diagnostic and prognostic performance. In doing so, we aim to address the question we asked three years ago about the potential of these techniques in laboratory medicine and the need to leverage a tool that was still under-utilised at that time. [ABSTRACT FROM AUTHOR]

The article reports that the 24th annual conference of the IGLD e.V. will take place from March 5-6, 2020 in Germany.