The ultimate goal of harmonization, crucial to quality in laboratory medicine, is to improve patient outcomes by providing accurate, actionable laboratory information. Patients and healthcare professionals assume that clinical laboratory tests performed by different laboratories at different times on the same type of sample are comparable, and that results can be reliably and consistently interpreted. In this context the reporting units for tests can have a considerable influence on the numeric result. The harmonization of measurement units in laboratory report, leads to the provision of interchangeable and comparable results, thus maximizing the validity of laboratory information, and assuring a more accurate diagnosis and better treatment for the patient. However, although considerable efforts have been made in recent years, the criticisms continue. This opinion paper, prepared jointly by EFLM Committee Harmonization (C-H) and Committee Postanalytical phase (C-POST), describes the "general pragmatic approach" proposed in the drafting of guidelines for the harmonization of measurement units in reporting results, in order to ensure they are used as widely as possible.
- Klíčová slova
- harmonization, international system of units (SI), measurement units, reporting results,
- MeSH
- klinické laboratoře * normy MeSH
- klinické laboratorní techniky * normy MeSH
- laboratoře * normy MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Evropa MeSH
Vitamin D is a micronutrient with pleiotropic effects in humans. Due to sedentary lifestyles and increasing time spent indoors, a growing body of research is revealing that vitamin D deficiency is a global problem. Despite the routine measurement of vitamin D in clinical laboratories and many years of efforts, methods of vitamin D analysis have yet to be standardized and are burdened with significant difficulties. This review summarizes several key analytical and clinical challenges that accompany the current methods for measuring vitamin D. According to an external quality assessment, methods and laboratories still produce a high degree of variability. Structurally similar metabolites are a source of significant interference. Furthermore, there is still no consensus on the normal values of vitamin D in a healthy population. These and other problems discussed herein can be a source of inconsistency in the results of research studies.
- Klíčová slova
- LC–MS/MS, VDR, determination, genomic effects, metabolites, non-genomic effects, vitamin D,
- MeSH
- hodnocení stavu výživy * MeSH
- klinické laboratorní techniky metody normy MeSH
- laboratoře normy MeSH
- lidé MeSH
- nedostatek vitaminu D diagnóza MeSH
- referenční hodnoty MeSH
- referenční standardy MeSH
- reprodukovatelnost výsledků MeSH
- vitamin D analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- vitamin D MeSH
Interlaboratory evaluations of Mucorales qPCR assays were developed to assess the reproducibility and performance of methods currently used. The participants comprised 12 laboratories from French university hospitals (nine of them participating in the Modimucor study) and 11 laboratories participating in the Fungal PCR Initiative. For panel 1, three sera were each spiked with DNA from three different species (Rhizomucor pusillus, Lichtheimia corymbifera, Rhizopus oryzae). For panel 2, six sera with three concentrations of R. pusillus and L. corymbifera (1, 10, and 100 genomes/ml) were prepared. Each panel included a blind negative-control serum. A form was distributed with each panel to collect results and required technical information, including DNA extraction method, sample volume used, DNA elution volume, qPCR method, qPCR template input volume, qPCR total reaction volume, qPCR platform, and qPCR reagents used. For panel 1, assessing 18 different protocols, qualitative results (positive or negative) were correct in 97% of cases (70/72). A very low interlaboratory variability in Cq values (SD = 1.89 cycles) were observed. For panel 2 assessing 26 different protocols, the detection rates were high (77-100%) for 5/6 of spiked serum. There was a significant association between the qPCR platform and performance. However, certain technical steps and optimal combinations of factors may also impact performance. The good reproducibility and performance demonstrated in this study support the use of Mucorales qPCR as part of the diagnostic strategy for mucormycosis.
- Klíčová slova
- Mucorales PCR, circulating DNA, interlaboratory assay, standardization,
- MeSH
- diagnostické techniky molekulární normy MeSH
- DNA fungální genetika MeSH
- klinické laboratorní techniky přístrojové vybavení metody normy MeSH
- kvantitativní polymerázová řetězová reakce normy MeSH
- lidé MeSH
- Mucorales genetika MeSH
- mukormykóza krev diagnóza MeSH
- nemocnice univerzitní statistika a číselné údaje MeSH
- odchylka pozorovatele MeSH
- reprodukovatelnost výsledků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- multicentrická studie MeSH
- Geografické názvy
- Francie MeSH
- Názvy látek
- DNA fungální MeSH
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.
- Klíčová slova
- EFLM, ISO 15189, examination procedure, opinion paper, validation, verification,
- MeSH
- akreditace normy MeSH
- dokumentace MeSH
- klinické laboratorní techniky normy MeSH
- lidé MeSH
- referenční standardy MeSH
- společnosti vědecké normy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
- Geografické názvy
- Evropa MeSH
OBJECTIVE: Group A rotavirus (RVA) is one of leading causes of gastroenteritis in children under five years of age and is also an important nosocomial pathogen. In Europe, the most prevalent genotypes of RVA are G1P[8], G2P[4], G3P[8], G4P[8], G9P[8] and G12P[8]. Severe dehydration is the most important complication of RVA gastroenteritis. Each year, rotavirus infection is responsible for 3,000 to 5,000 hospitalizations of children in the Czech Republic. The aim of this study was to detect rotaviruses in patients with suspected acute viral gastroenteritis. METHODS: A total of 1 566 stool samples were obtained from patients with acute gastroenteritis from March 2016 to December 2018. All samples were tested by the enzyme immunoassay, rapid immunochromatographic test and quantitative reverse transcription PCR assay to detect RVA. All RVA positive samples were G- and P-typed by Sanger sequencing. RESULTS AND CONCLUSION: RVA was detected in 13.7 % of the samples (214/1566). The incidence of RVA was 58.9 % (126/214) in males and 41.1 % (88/214) in females. The percentages of positivity ranged from 1 % to 33 % in different age groups. The highest proportion of positive patients was in the age group 4-5 years, 32.6 % (30/92). There was a significant difference in the incidence of rotaviruses between different age groups (p = 0.3946). The prevalent RVA genotypes were G1P[8], G9P[8], G3P[8], G2P[4] and G8P[8]. The detection of the G8P[8] genotype was unusual. The obtained results show that despite the possibility of vaccination, the incidence of RVA infection remains high in the Czech Republic.
- MeSH
- dítě MeSH
- genotyp MeSH
- imunoanalýza MeSH
- imunoenzymatické techniky MeSH
- incidence MeSH
- klinické laboratorní techniky * normy MeSH
- kojenec MeSH
- lidé MeSH
- polymerázová řetězová reakce s reverzní transkripcí MeSH
- předškolní dítě MeSH
- RNA virová genetika MeSH
- rotavirové infekce * diagnóza epidemiologie patologie virologie MeSH
- Rotavirus * genetika izolace a purifikace MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
- Názvy látek
- RNA virová MeSH
BACKGROUND: von Willebrand disease (VWD) is an inherited bleeding disorder caused by a quantitative (type 1 and 3) or qualitative (type 2) defect of von Willebrand factor (VWF). The heterogeneity of laboratory phenotyping makes diagnosing difficult. OBJECTIVE: A cross-sectional, family-based VWD study in a collaboration between University Hospital Brno (Czech Republic) and Antwerp University Hospital (Belgium) to improve the understanding of laboratory phenotype/genotype correlation. PATIENTS AND METHODS: A total of 205 patients with suspected VWD were identified from historical records. Complete laboratory analysis was established using all available VWD assays including VWF multimers and genetic analysis. RESULTS: Based on the current International Society of Thrombosis and Haemostasis (ISTH) - Scientific and Standardization Committee VWD classification and type 2A sub-division into 2A/IIA, IID, IIC and IIE, the majority was characterized as a type 1 VWD, followed by type 2. Proposed laboratory phenotypes were confirmed by their multimeric pattern within 98% of this cohort. All type 2, 3 and 75% of type 1 VWD patients were confirmed by underlying causative mutations. Forty-six different causal mutations (117 not previously described in the literature) could be identified. Fifty per cent of all cases was represented by eight individual mutations, mainly p.Pro812ArgfsX31. Thirteen patients had a large heterozygous gene alteration. CONCLUSION: Although an extensive panel of tests was used, VWD classification and (sub)typing remains difficult and fluid. This study provides a cross-sectional overview of the VWD population in the Czech Republic and provides important data to the ISTH/European Association for Haemophilia and Allied Disorders VWD mutation database in linking causal mutations with unique VWD (sub)types. It also identifies new, as not previously described in the literature, causal mutations.
- MeSH
- dítě MeSH
- doba krvácení MeSH
- dospělí MeSH
- fenotyp MeSH
- heterozygot MeSH
- klinické laboratorní techniky normy MeSH
- kojenec MeSH
- krvácení genetika MeSH
- lidé MeSH
- mezinárodní spolupráce MeSH
- mladiství MeSH
- mladý dospělý MeSH
- multimerizace proteinu MeSH
- mutace MeSH
- novorozenec MeSH
- odběr biologického vzorku MeSH
- předškolní dítě MeSH
- průřezové studie MeSH
- von Willebrandova nemoc krev diagnóza epidemiologie MeSH
- von Willebrandův faktor analýza genetika MeSH
- vyšetření krevní srážlivosti MeSH
- zdraví rodiny MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Belgie MeSH
- Česká republika epidemiologie MeSH
- Názvy látek
- von Willebrandův faktor MeSH
Clostridium difficile, a causative agent of intestinal infections (CDI) of varying severity, is an important nosocomial pathogen. Microbiological diagnosis, including an appropriate test algorithm and the corresponding interpretation of the results, is crucial for CDI confirmation. This update is based on the European guidance document for CDI laboratory diagnosis, taking into account the current CDI epidemiology and laboratory diagnostic approaches in the Czech Republic. Any diarrhoeal patient should be tested for CDI. The rectal swabs can only be used for testing in patients with paralytic ileus. Currently, a two-step test algorithm is recommended for CDI diagnosis. Due to a low positive predictive value, a single commercial test is not recommended as a stand-alone test for diagnosing CDI. Samples with a positive screening test (glutamate dehydrogenase or toxigenic strain nucleic acid) and a subsequent negative EIA (enzyme immunoassay) test for the presence of free toxins are diagnostically inconclusive. An option is to use a third confirmatory test; however, the current clinical status of the patient along with other laboratory findings should be considered in order to differentiate between ongoing CDI, carriage of a toxigenic strain of C. difficile, and other causes of diarrhoea. In general, when implementing a new diagnostic test, its sensitivity and specificity should be compared against the reference method. Diagnostic tests should refer to the data from published comparative studies and should not rely solely on information provided by the manufacturer. Currently, there is no commercial test available for detection of free C. difficile toxins in stool samples with 100 % sensitivity. Moreover, the pre-analytical conditions (storage and transport temperature of stool samples) and/or the initiation of an empirical therapy prior to the sampling may decrease the sensitivity of the assay.
- Klíčová slova
- Clostridium difficile - laboratory diagnosis - laboratory testing algorithm - result interpretation.,
- MeSH
- bakteriální toxiny analýza MeSH
- Clostridioides difficile * MeSH
- feces mikrobiologie MeSH
- imunoenzymatické techniky MeSH
- klinické laboratorní techniky * normy MeSH
- klostridiové infekce * diagnóza MeSH
- lidé MeSH
- senzitivita a specificita MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- směrnice MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- bakteriální toxiny MeSH
- MeSH
- bakteriální proteiny genetika MeSH
- bakteriální toxiny genetika MeSH
- Clostridioides difficile * klasifikace genetika MeSH
- enterotoxiny genetika MeSH
- fenotyp MeSH
- klinické laboratorní techniky * metody normy MeSH
- klostridiové infekce diagnóza mikrobiologie MeSH
- kolonoskopie MeSH
- kultivační média MeSH
- lidé MeSH
- polymerázová řetězová reakce metody normy MeSH
- pseudomembranózní enterokolitida diagnóza mikrobiologie MeSH
- reprodukovatelnost výsledků MeSH
- ribotypizace metody normy MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- dopisy MeSH
- přehledy MeSH
- Názvy látek
- bakteriální proteiny MeSH
- bakteriální toxiny MeSH
- enterotoxiny MeSH
- kultivační média MeSH
- tcdA protein, Clostridium difficile MeSH Prohlížeč
- toxB protein, Clostridium difficile MeSH Prohlížeč
The aim of this opinion is to summarize and to comment the consensus of the European Atherosclerosis Society and European Federation of Clinical Chemistry and Laboratory Medicine, which covers two main areas: 1) whether it is necessary / required to be fasting or non-fasting before blood sampling for lipids measurement, and what are the changes in the concentration of blood lipids during the day; 2) What decision limits (cut off value) of lipids and lipoproteins should be reported from laboratories and what is the recommended procedure for people with extreme / critical blood lipid values. Following parameters are discused: total cholesterol, LDL cholesterol, HDL cholesterol, non-HDL cholesterol, triglycerides, apolipoprotein A1, apolipoprotein B, lipoprotein(a). This opinion should be the object of interest both for professionals in clinical laboratories and for physicians in hospitals and out-patients departments.Key words: apolipoproteins - blood collection - cholesterol - laboratory testing - lipoprotein(a) - cut off limits - triglycerides.
- MeSH
- apolipoproteiny krev MeSH
- ateroskleróza krev MeSH
- cholesterol krev MeSH
- HDL-cholesterol krev MeSH
- klinická chemie normy MeSH
- klinické laboratorní techniky normy MeSH
- konsensus MeSH
- LDL-cholesterol krev MeSH
- lidé MeSH
- lipoproteiny krev MeSH
- společnosti lékařské MeSH
- triglyceridy krev MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Názvy látek
- apolipoproteiny MeSH
- cholesterol MeSH
- HDL-cholesterol MeSH
- LDL-cholesterol MeSH
- lipoproteiny MeSH
- triglyceridy MeSH
Since the 1990s, blood donors have been scanned for anti-hepatitis C virus (anti-HCV) antibodies, which can be defined by enzyme immunoassay as a screening test. In this population, false-reactive ratios have been high. Recently, some authors have aimed to find a cutoff value for anti-HCV different from those established by test manufacturers to predict HCV infection. In this study, 321 patients, after two repeating tests, had reactive results in s/co <10 titers on anti-HCV test. The patients were 29.6 % (n = 95) in women and 70.4 % (n = 226) in men. The patients were classified into three groups by Western blot (WB) results (PS, positive; NG, negative; and ID, indeterminate). The average anti-HCV titer of the whole group was 2.61 ± 1.96. Anti-HCV titers of subgroups were 2.43 ± 1.95 in NG, 4.93 ± 2.53 in PS, and 2.50 ± 1.65 in ID (p < 0.001). There was a significant difference between NG and PS and between PS and ID subgroups (p < 0.001). There was a positive correlation between WB and anti-HCV titers in all patients (r = 0.298, p < 0.001), in women (r = 0.282, p < 0.001), and in men (r = 0.337, p = 0.002). According to receiver operator characteristic curve analysis, the cutoff value of anti-HCV titer to predict hepatitis C infection was >2.61 s/co, with 74.1 % sensitivity and 71.6 % specificity (area under the curve, 0.820; 95 % confidence interval, 0.753 to 0.887). We suggest that an effective cutoff value for anti-HCV other than that established by the manufacturer cannot be assigned to predict hepatitis C infection for blood donors in low-prevalence areas.
- MeSH
- chronická hepatitida C diagnóza imunologie MeSH
- Hepacivirus imunologie MeSH
- hepatitida C - protilátky krev MeSH
- klinické laboratorní techniky metody normy MeSH
- lidé MeSH
- prediktivní hodnota testů MeSH
- senzitivita a specificita MeSH
- western blotting metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- Názvy látek
- hepatitida C - protilátky MeSH
