40,630 research outputs found
The EFLM strategy for harmonization of the preanalytical phase
No full textThe Working Group for the Preanalytical Phase (WG-PRE) was officially established by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) in 2013, with the aim of improving harmonization in the preanalytical phase across European member societies. Since its early birth, the WG-PRE has already completed a number of projects, including harmonizing the definition of fasting status, patient and blood tubes identification, color coding of blood collection tubes, sequence of tubes during blood drawing and participation in the development of suitable preanalytical quality indicators. The WG-PRE has also provided guidance on local validation of blood collection tubes, has performed two European surveys on blood sampling procedures and has organized four European meetings to promote the importance of quality in the preanalytical phase. The future activities entail development and validation of an external quality assessment scheme focused on preanalytical variables, development and dissemination of a survey about the local management of unsuitable samples in clinical laboratories, as well as release of EFLM phlebotomy guidelines. This article summarizes all recent achievements of the WG-PRE and illustrates future projects to promote harmonization in the preanalytical phase
The preanalytical phase in the era of high-throughput genetic testing. What the future holds
No full textThe preanalytical phase in the era of high-throughput genetic testing. What the future hold
Potential preanalytical and analytical vulnerabilities in the laboratory diagnosis of coronavirus disease 2019 (COVID-19)
No full textA novel zoonotic coronavirus outbreak is spreading all over the world. This pandemic disease has now been defined as novel coronavirus disease 2019 (COVID-19), and is sustained by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As the current gold standard for the etiological diagnosis of SARS-CoV-2 infection is (real time) reverse transcription polymerase chain reaction (rRT-PCR) on respiratory tract specimens, the diagnostic accuracy of this technique shall be considered a foremost prerequisite. Overall, potential RT-PCR vulnerabilities include general preanalytical issues such as identification problems, inadequate procedures for collection, handling, transport and storage of the swabs, collection of inappropriate or inadequate material (for quality or volume), presence of interfering substances, manual errors, as well as specific aspects such as sample contamination and testing patients receiving antiretroviral therapy. Some analytical problems may also contribute to jeopardize the diagnostic accuracy, including testing outside the diagnostic window, active viral recombination, use of inadequately validated assays, insufficient harmonization, instrument malfunctioning, along with other specific technical issues. Some practical indications can hence be identified for minimizing the risk of diagnostic errors, encompassing the improvement of diagnostic accuracy by combining clinical evidence with results of chest computed tomography (CT) and RT-PCR, interpretation of RT-PCR results according to epidemiologic, clinical and radiological factors, recollection and testing of upper (or lower) respiratory specimens in patients with negative RT-PCR test results and high suspicion or probability of infection, dissemination of clear instructions for specimen (especially swab) collection, management and storage, together with refinement of molecular target(s) and thorough compliance with analytical procedures, including quality assurance
Innovative software for recording preanalytical errors in accord with the IFCC quality indicators
No full textInnovative software for recording preanalytical errors in accord with the IFCC quality indicators
Call for more transparency in manufacturers declarations on serum indices: On behalf of the Working Group for Preanalytical Phase (WG-PRE), European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)
No full textThe presence of interfering substances like free hemoglobin, bilirubin or lipids compromises sample quality and potentially affects laboratory analysis and test results. Recently, the use of serum indices for objectively assessing sample quality has become commonplace and many preanalytical platforms, as well as clinical chemistry and coagulation analyzers, are now equipped with this analytical feature. Nevertheless, some important drawbacks remain in this practice, mainly pertaining the measurement procedure, the approach for reporting interference data, the definition of objective thresholds of interference after which test results may be biased, and the lack of harmonized practices for describing how interference cut-offs have been identified. Therefore, this document aims to discuss these important caveats and propose some reliable solutions that may be adopted by manufacturers for increasing worldwide harmonization of serum indices
Blood sample quality
No full textSeveral lines of evidence now confirm that the vast majority of errors in laboratory medicine occur in the extra-analytical phases of the total testing processing, especially in the preanalytical phase. Most importantly, the collection of unsuitable specimens for testing (either due to inappropriate volume or quality) is by far the most frequent source of all laboratory errors, thus calling for urgent strategies for improving blood sample quality and managing data potentially generated measuring unsuitable specimens. A comprehensive overview of scientific literature leads us to conclude that hemolyzed samples are the most frequent cause of specimen non-conformity in clinical laboratories (40-70%), followed by insufficient or inappropriate sample volume (10-20%), biological samples collected in the wrong container (5-15%) and undue clotting (5-10%). Less frequent causes of impaired sample quality include contamination by infusion fluids (i.e. most often saline or glucose solutions), cross-contamination of blood tubes additives, inappropriate sample storage conditions or repeated freezing-thawing cycles. Therefore, this article is aimed to summarize the current evidence about the most frequent types of unsuitable blood samples, along with tentative recommendations on how to prevent or manage these preanalytical non-conformities
Practical recommendations for managing hemolyzed samples in clinical chemistry testing
No full textWe suggest here a pragmatic approach for managing results of clinical chemistry testing in hemolyzed samples collected from adults/older children, attempting to balance the need to produce quality laboratory data with clinical urgency of releasing test results. Automatic measurement of the hemolysis index (H-index) in serum or plasma is highly advisable, whilst low-quality assessment of this test remains less good than a visual inspection. Regarding its practical use, when the H-index value does not generate an analytically significant bias, results can be released, whilst when the value is associated with analyte variation in a range between analytically and clinically significant bias (i.e. variation does not exceed the reference change value [RCV]), results of hemolysis-sensitive tests can be released in association with a comment describing the direction in which data are potentially altered, suggesting the need to collect another sample. When the H-index is associated with analyte variation exceeding clinically significant bias (i.e. variation exceeds the RCV), results of hemolysis-sensitive tests should be suppressed and replaced with a comment that biased results cannot be released because the sample is preanalytically compromised and advising the recollection of another sample. If H-index values reach an even higher critical cut-off (i.e. H-index corresponding to a cell-free hemoglobin concentration ≥10 g/L), all laboratory data may be unreliable and should hence be suppressed and replaced with a comment that all data cannot be released because the sample is grossly hemolyzed, also suggesting the recollection of another sample. Due to inaccuracy and imprecision, the use of corrective formulas for adjusting data of hemolysis-sensitive tests is discouraged
Local quality assurance of serum or plasma (HIL) indices
No full textThe presence of hemolysis (H), icterus (I) and lipaemia (L) in serum or plasma samples may be regarded as an important preanalytical drawback, since an abnormal concentration of these substances may derange the global quality and reliability of the total testing process. Although the assessment of sample quality before testing by means of the so-called HIL indices has become an essential part of routine practice in most clinical laboratories worldwide, no clear indications have been provided about the quality assurance of these measures. This article is hence aimed to provide an expert opinion about management of internal quality control (IQC) assessment for HIL indices. In summary, we support the use of in-house prepared IQC materials with at least two different levels for each interfering substances. IQC testing should be performed for validating performance of HIL indices in routine and urgent conditions, at least 2 times per day, and systematically recorded. We also suggest that results may be unacceptable when a single value of IQC material exceeds the mean target value by ±3 standard deviations. When results do not meet their set performance goals, the ensuing procedure mirrors that of conventional laboratory IQC management
Exact time of venous blood sample collection - an unresolved issue, on behalf of the European Federation for Clinical Chemistry and Laboratory Medicine (EFLM) Working Group for Preanalytical Phase (WG-PRE)
No full textObjectives An accurate knowledge of blood collection times is crucial for verifying the stability of laboratory analytes. We therefore aimed to (i) assess if and how this information is collected throughout Europe and (ii) provide a list of potentially available solutions. Methods A survey was issued by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group on Preanalytical Phase (WG-PRE) in 2017, aiming to collect data on preanalytical process management, including sampling time documentation, in European laboratories. A preceding pilot survey was disseminated in Austria in 2016. Additionally, preanalytical experts were surveyed on their local setting on this topic. Finally, the current scientific literature was reviewed on established possibilities of sampling time collection. Results A total number of 85 responses was collected from the pilot survey, whilst 1347 responses from 37 European countries were obtained from the final survey. A minority (i.e. ~13%) of responders to the latter declared they are unaware of the exact sampling time. The corresponding rate in Austria was ~70% in the pilot and ~30% in the final survey, respectively. Answers from 17 preanalytical experts from 16 countries revealed that sampling time collection seems to be better documented for out- than for in-patients. Eight different solutions for sample time documentation are presented. Conclusions The sample collection time seems to be documented very heterogeneously across Europe, or not at all. Here we provide some solutions to this issue and believe that laboratories should urgently aim to implement one of these
PREDICT: a checklist for preventing preanalytical diagnostic errors in clinical trials
No full textAlthough the importance of guaranteeing a high level of preanalytical quality in routine diagnostic testing has already been largely acknowledged over the past decades, minor emphasis is currently being placed on the fact that accurate performance and standardization of many preanalytical activities are also necessary prerogatives of clinical trials. Reliable evidence exists that clear indications on how to manage the different preanalytical steps are currently lacking in many clinical trials protocols, nor have detailed authoritative documents been published or endorsed on this matter to the best of our knowledge. To fill this gap, the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group for Preanalytical Phase (WG-PRE) will provide here a specific checklist for preventing preanalytical diagnostic errors in clinical trials (PREDICT), especially focused on covering the most important preanalytical aspects of blood sample management in clinical studies, and thus encompassing test selection, patient preparation, sample collection, management and storage, sample transportation, as well as specimen retrieval before testing. The WG-PRE members sincerely hope that these recommendations will provide a useful contribution for increasing the success rate in clinical trials
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