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Gran parte de la actividad en el laboratorio clínico debe quedar documentada para facilitar el mantenimiento de la calidad del servicio, lo que deriva en la generación de una gran cantidad de documentación, formularios e informes. Con tal objeto, es necesario especificar el tiempo de retención requerido para cada tipo de documento y muestra. Además de la obligación de conservar los informes del laboratorio clínico como parte de la historia clínica de los pacientes, el laboratorio también está obligado por ley, o según las directrices de las organizaciones profesionales, si las hubiera, a retener un gran volumen de documentación y muestras. En caso contrario, la dirección del laboratorio deberá establecer un calendario de retención, en el que se especifiquen las condiciones y el periodo de conservación, de acuerdo con los requisitos de la norma ISO 15189:2022 sobre retención de documentación y registros de gestión de la calidad.

Many aspects of the activity of a medical laboratory have to be documented so as to facilitate the maintenance of the ongoing quality of service. As a consequence, many documents, forms and reports are generated. The retention time for each of these has to be specified. In addition to medical laboratory reports as part of the patient’s medical record, the medical laboratory has to retain many documents and specimens according to national legislation or guidance from professional organizations, if these exist. If not, the laboratory management needs to define a retention schedule, which shall define the storage conditions and period of storage, according to ISO 15189:2022 requirements for retention of general quality management documents and records. The EFLM Working Group on Accreditation and ISO/CEN standards provides here a proposal on retention periods of documentation and specimens based on a failure-mode-effects-analysis (FMEA) risk-based approach, a concept of risk reduction that has become an integral part of modern standards.

Timely identification of excessive alcohol use and its potential complications is a prerequisite for successful treatment. Several routine tests have been used in laboratories that may help in diagnosing alcoholism, such as determination of MCV, AST, ALT, GGT, but it has been shown that they lack specificity and sensitivity. Contemporary biomarkers are increasingly being used today that may due to their unique characteristics help in discovering the onset of chronic alcohol abuse, as well as in abstinence and relapse monitoring. The term carbohydrate-deficient transferrin (CDT) stands for a small group of human transferrin isoforms (asialo, monosialo, and disialotran sferrin) with a lower degree of glycosylation in comparison to the dominant transferrin isoform (tetrasialotransferrin). Persons consuming large quantities of alcohol (≥50-80 g daily) over a period of at least two weeks have increased concentrations of transferrin isoforms lacking one (disialo transferrin) or both (asialotran - sferrin) carbohydrate chains. In this paper the traditional markers of chronic alcohol abuse (GGT, AST, ALT, and MCV) were determined, as well as the new biomarker CDT, after which diagnostic evaluation was performed and their usability and clinical value in routine laboratory practice were estimated. These markers were also determined in heavy alcoholics on admission into hospital and after two weeks of therapy, with the aim of estimating their diagnostic value for abstinence and relapse monitoring.

It has long been known that a hypercoagulability state develops after surgery. The aim of the study was to evaluate the influence of chronic cholecystitis on haemostasis. Surgical operation at this diagnosis imply classic open cholecistectomy (so called OC method) and laparoscopic method (LC method). That was the criteria for category in two groups patients. The patients with acute cholecystitis were excluded. Prothrombin time, aPTT fibrinogen, antithrombin III (AT III), protein C, plasminogen and D-dimer levels were measured at baseline and at 1, 2, 3, 5 and 7 days after the operation. Plasma levels of haemostatic parameters were measured by spectrofotometric assay with chromogenic substrat, on BCS (Behring Coagulation System, Dade Behring). Preoperative parameters of hemostasis were normal in all the patients. Plasma levels of fibrinogen and D-dimer increased significantly in group OC. Plasma levels of AT III, protein C and plasminogen decreased in both groups. Patients received low-molecular heparin -Fraxarin. The investigation of hemostasis parameters on days 1, 2, 3, 5 and 7 after the operation showed that after laparoscopic cholecystectomy restores the balance in the hemostasis system by the 3rd day, and by the 7th day after open cholecystectomy. Recently laparoscopic cholecystectomy (LC) has advantages over the open procedure seem related to the reduced surgical trauma. LC is associated with a diminished acute-phase response and reduce the risk of thromboembolic complications one has to take into account the changes of hemostasis balance.

This paper reflects the opinion of the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group Accreditation and ISO/CEN standards (WG-A/ISO). It aims to provide guidance for drawing up local/national documents about validation and verification of laboratory methods. We demonstrate how risk evaluation can be used to optimize laboratory policies to meet intended use requirements as well as requirements of standards. This is translated in a number of recommendations on how to introduce risk evaluation in various stages of the implementation of new methods ultimately covering the whole process cycle.

ISO15189:2012 requires medical laboratories to document metrological traceability of their results. While the ISO17511:2003 standard on metrological traceability in laboratory medicine requires the use of the highest available level in the traceability chain, it recognizes that for many measurands there is no reference above the manufacturer's selected measurement procedure and the manufacturer's working calibrator. Some immunoassays, although they intend to measure the same quantity and may even refer to the same reference material, unfortunately produce different results because of differences in analytical selectivity as manufacturers select different epitopes and antibodies for the same analyte. In other cases, the cause is the use of reference materials, which are not commutable. The uncertainty associated with the result is another important aspect in metrological traceability implementation. As the measurement uncertainty on the clinical samples is influenced by the uncertainty of all steps higher in the traceability chain, laboratories should be provided with adequate and appropriate information on the uncertainty of the value assignment to the commercial calibrators that they use. Although the between-lot variation in value assignment will manifest itself as part of the long-term imprecision as estimated by the end-user, information on worst-case to be expected lot-lot variation has to be communicated to the end-user by the IVD provider. When laboratories use ancillary equipment that potentially could have a critical contribution to the reported results, such equipment needs verification of its proper calibration and criticality to the result uncertainty could be assessed by an approach based on risk analysis, which is a key element of ISO15189:2012 anyway. This paper discusses how the requirement for metrological traceability as stated in ISO15189 should be met by the medical laboratory and how this should be assessed by accreditation bodies.

This document is based on the original recommendation of the Expert Panel on the Theory of Reference Values of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC), updated guidelines were recently published under the auspices of the IFCC and the Clinical and Laboratory Standards Institute (CLSI). This document summarizes proposals for recommendations on: (i) The terminology, which is often confusing, noticeably concerning the terms of reference limits and decision limits. (ii) The method for the determination of reference limits according to the original procedure and the conditions, which should be used. (iii) A simple procedure allowing the medical laboratories to fulfill the requirements of the regulation and standards. The updated document proposes to verify that published reference limits are applicable to the laboratory involved. Finally, the strengths and limits of the revised recommendations (especially the selection of the reference population, the maintenance of the analytical quality, the choice of the statistical method used…) will be briefly discussed.

Background: Accreditation is a valuable resource for medical laboratories. The development of quality systems based on ISO 15189 has taken place in many laboratories in the European countries but data about accreditation remain scarce. The EFLM Working Group "Accreditation and ISO/CEN standards" conducted a survey that reviews the current state of the accreditation process in European countries., Methods: An on-line questionnaire was addressed to delegates of 39 EFLM scientific societies in March 2014. One answer by country was taken into account. The survey was dealing with mandatory status, number of accredited medical laboratories in each country, possibility of flexible scope and concerned medical fields. The status of point-of-care testing (POCT) in each country was also studied., Results: Twenty-nine responses (74%) were registered. All the assessed countries (100%) have begun an accreditation process in various ways. All the national accreditation bodies (NAB) offer or are working to offer an ISO 15189 accreditation. The accreditation process most often concerns all phases of the examination and various medical fields. Medical laboratories are responsible for POCT in 20 (69%) countries. The accreditation process for POCT, according to ISO 15189 and ISO 22870, is also developing., Conclusions: While there are several variations in the approaches to accreditation of medical laboratories in the European countries, the ISO 15189 accreditation project has been widely accepted. The use of a unique standard and the cooperation among countries due to scientific societies, EFLM, accreditation bodies and EA enable laboratory professionals to move toward uniform implementation of the accreditation concept.

The recent revision of ISO15189 has further strengthened its position as the standard for accreditation for medical laboratories. Both for laboratories and their customers it is important that the scope of such accreditation is clear. Therefore the European co-operation for accreditation (EA) demands that the national bodies responsible for accreditation describe the scope of every laboratory accreditation in a way that leaves no room for doubt about the range of competence of the particular laboratories. According to EA recommendations scopes may be fixed, mentioning every single test that is part of the accreditation, or flexible, mentioning all combinations of medical field, examination type and materials for which the laboratory is competent. Up to now national accreditation bodies perpetuate use of fixed scopes, partly by inertia, partly out of fear that a too flexible scope may lead to over-valuation of the competence of laboratories, most countries only use fixed scopes. The EA however promotes use of flexible scopes, since this allows for more readily innovation, which contributes to quality in laboratory medicine. In this position paper, the Working Group Accreditation and ISO/CEN Standards belonging to the Quality and Regulation Committee of the EFLM recommends using an approach that has led to successful introduction of the flexible scope for ISO15189 accreditation as intended in EA-4/17 in The Netherlands. The approach is risk-based, discipline and competence-based, and focuses on defining a uniform terminology transferable across the borders of scientific disciplines, laboratories and countries.

Background: The aim of the study was to identify the diagnostic significance of presepsin in acute abdominal conditions and also to examine the correlation between presepsin, procalcitonin (PCT) and other parameters., Methods: To detect presepsin we used a new rapid method based on a chemiluminescent enzyme immunoassay. The clinical usefulness of presepsin to differentiate bacterial and non-bacterial infection [including systemic inflammation response syndrome (SIRS)] was studied and compared with PCT, C-reactive protein (CRP) and white blood cells (WBC)., Results: The presepsin values in different conditions were (mean±standard deviation): healthy group (n=70) 258.7±92.53 pg/mL; SIRS (n=30) 430.0±141.33 pg/mL; sepsis (n=30) 1508.3±866.6 pg/mL. The presepsin values were significantly higher in patients with sepsis than the SIRS group (p<0.0001, Mann-Whitney U-test). The area under the receiver operating characteristics (ROC) curve (AUC) for discriminating of the SIRS from the sepsis patients was 0.996 for presepsin and it was greater than the AUC of PCT (0.912), CRP (0.857) or WBC (0.777)., Conclusions: The ROC curve of the SIRS patient without infection and the sepsis patient showed that the presepsin concentration was a significantly sensitive indicator of sepsis and useful marker for the rapid diagnosis of sepsis.

Background and Aims: The present study attempted to identify the diagnostic significance of procalcitonin (PCT) in acute abdominal conditions as well as the range of concentrations relating to diagnosis of abdominal sepsis., Materials and Methods: This was prospective clinical study. The study included 98 consecutive patients with acute abdominal conditions, divided in sepsis and systemic inflammatory response syndrome (SIRS) group., Results: PCT concentrations on admission were significantly higher in the sepsis group than in the SIRS group (median [interquartile range] 2.32 [7.41] vs 0.45 ng/ml [2.62]). A cutoff value of 1.1 ng/ml yielded 72.4% sensitivity and 62.5% specificity. In a group of patients with abdominal symptoms lasting for more than 24 h, a cut-off value of 1.1 ng/ml yielded higher sensitivity (82.9%) and higher specificity (77.3%)., Conclusion: Our results suggest that PCT measurements may be useful for early, preoperative diagnosis of abdominal sepsis.