Hemolysis detection and management of hemolyzed specimens

Assay interferences have long been underestimated and unfortunately too often undetected in the daily clinical laboratory practice. The extra-analytical phase of the laboratory testing process has been recognized as the major source of laboratory errors over the past decade. Preanalytical errors are most common errors within the total testing process and hemolysis is recognized as one of the most prevalent preanalytical errors and surely the most prevalent interference in clinical laboratory testing. Visual detection of hemolysis is arbitrary and therefore mostly unreliable since it may over- and underestimate the actual prevalence of hemolyzed serum specimens (i.e., trained observers are unable to accurately rank the degree of interference in serum). Elevated concentration of bilirubin may further impair the ability to detect hemolysis by visual inspection and therefore lead to serious underestimation of hemolysis in neonatal samples where elevated bilirubin concentration is commonplace. The recent advances in laboratory technology have lead to an increasing trend in the automation of various preanalytical processes into large preanalytical modules. Such modules as well as novel automated laboratory analyzers offer the automated detection of serum indices. This is advantageous due to the increased reproducibility and the improvement in detection of mildly hemolyzed specimens (serum hemoglobin < 0.6 g/L). These platforms commonly use the semiquantitative spectrophotometric measurement and grade interfering substances into several categories. However, various analytical platforms may have different decision thresholds for various serum indices. Moreover, different systems might be different in their assay parameters and the degree of the interference of the specific interfering substance. Therefore, more efforts should be focused to standardize the mean of reporting the hemolysis index, especially when this important parameter is used for obtaining meaningful information on the quality of sample collection throughout collection centers and wards. Hemolysis is still one of the biggest challenges to the laboratory specialists. In case of hemolysis, laboratory personnel should always ask for new sample(s). In case new sample(s) can not be obtained, it is the responsibility of the laboratory specialist to communicate the problem with the physician responsible for the patient and seek for the solution to the best of the patient care

Hemolysis detection and management of hemolyzed specimens

Assay interferences have long been underestimated and unfortunately too often undetected in the daily clinical laboratory practice. The extra-analytical phase of the laboratory testing process has been recognized as the major source of laboratory errors over the past decade. Preanalytical errors are most common errors within the total testing process and hemolysis is recognized as one of the most prevalent preanalytical errors and surely the most prevalent interference in clinical laboratory testing. Visual detection of hemolysis is arbitrary and therefore mostly unreliable since it may over- and underestimate the actual prevalence of hemolyzed serum specimens (i.e., trained observers are unable to accurately rank the degree of interference in serum). Elevated concentration of bilirubin may further impair the ability to detect hemolysis by visual inspection and therefore lead to serious underestimation of hemolysis in neonatal samples where elevated bilirubin concentration is commonplace. The recent advances in laboratory technology have lead to an increasing trend in the automation of various preanalytical processes into large preanalytical modules. Such modules as well as novel automated laboratory analyzers offer the automated detection of serum indices. This is advantageous due to the increased reproducibility and the improvement in detection of mildly hemolyzed specimens (serum hemoglobin < 0.6 g/L). These platforms commonly use the semiquantitative spectrophotometric measurement and grade interfering substances into several categories. However, various analytical platforms may have different decision thresholds for various serum indices. Moreover, different systems might be different in their assay parameters and the degree of the interference of the specific interfering substance. Therefore, more efforts should be focused to standardize the mean of reporting the hemolysis index, especially when this important parameter is used for obtaining meaningful information on the quality of sample collection throughout collection centers and wards. Hemolysis is still one of the biggest challenges to the laboratory specialists. In case of hemolysis, laboratory personnel should always ask for new sample(s). In case new sample(s) can not be obtained, it is the responsibility of the laboratory specialist to communicate the problem with the physician responsible for the patient and seek for the solution to the best of the patient care

Clinical chemistry and laboratory medicine in Croatia: regulation of the profession

Heterogeneity exists across Europe in the definition of the profession of clinical chemistry and laboratory medicine and also in academic background of specialists in this discipline. This article pro-vides an overview of the standards of education and training of laboratory professionals and quality regulations in Croatia. Clinical chemistry in Croatia is almost exclusively practiced by medical bioc-hemists. Although term Medical biochemist often relates to medical doctors in other European coun-tries, in Croatia medical biochemists are not medical doctors, but university degree professionals who are qualified scientifically. Practicing the medical biochemistry is regulated by The Health Care Law, The Law of the Medical Biochemistry Profession and The Law of the State and Private Health Insu-rance. According to the law, only medical biochemists are entitled to run and work in the medical biochemistry laboratory. University degree is earned after the 5 years of the studies. Register for me-dical biochemists is kept by the Croatian Chamber of Medical Biochemists. Licensing is mandatory, valid for 6 years and regulated by the government (Law on the Health Care, 1993). Vocational training for medical biochemists lasts 44 months and is regulated by the national regulatory document issued by the Ministry of Health. Accreditation is not mandatory and is provided by an independent, non-commercial national accreditation body. The profession has interdisciplinary character and a level of required competence and skills comparable to other European countries

Comparison of visual vs. automated detection of lipemic, icteric and hemolyzed specimens: can we rely on a human eye?

Background: Results from hemolyzed, icteric, and lipemic samples may be inaccurate and can lead to medical errors. These preanalytical interferences may be detected using visual or automated assessment. Visual inspection is time consuming, highly subjective and not standardized. Our aim was to assess the comparability of automated spectrophotometric detection and visual inspection of lipemic, icteric and hemolyzed samples. Methods: This study was performed on 1727 routine biochemistry serum samples. Automated detection was performed using the Olympus AU2700 analyzer. We assessed: 1) comparability of visual and automated detection of lipemic, icteric and hemolyzed samples, 2) precision of automated detection, and 3) inter-observer variability for visual inspection. Results: Weighted κ coefficients for comparability of visual and automated detection were: 0.555, 0.529 and 0.638, for lipemic, icteric and hemolyzed samples, respectively. The precision for automated detection was high for all interferences, with the exception of samples being only slightly lipemic. The best overall agreement between observers was present in assessing lipemia (mean weighted κ=0.698), whereas the lowest degree of agreement was observed in assessing icterus (mean weighted κ=0.476). Conclusions: Visual inspection of lipemic, icteric and hemolyzed samples is highly unreliable and should be replaced by automated systems that report serum indices. Clin Chem Lab Med 2009;47:1361–5.Peer Reviewe

Frequency of factor II G20210A, factor V Leiden, MTHFR C677T and PAI-1 5G/4G polymorphism in patients with venous thromboembolism: Croatian case-control study

Introduction: Venous thromboembolic disease is one of the leading causes of morbidity and mortality in the developed world. Identification of hereditary factors of thrombophilia is contributing to a better understanding of the etiology and disease prevention. The aim of this study was to assess the prevalence of factor IIG20210A, factor V Leiden, MTHFR (methylenetetrahydrofolate reductase) C677T and PAI-1 (plasminogen activator inhibitor-1) 5G/4G polymorphisms in healthy Croatian subjects and patients with thromboembolism. Materials and methods: This prospective study included 100 thromboembolic patients consecutively admitted to the Intensive Care Unit, Sestre Milosrdnice University Hospital and 106 healthy subjects. Genotyping of factor IIG20210A, factor V Leiden, MTHFR C677T and PAI-1 5G/4G polymorphisms was done using melting curve analysis on Light Cycler 1.2 analyzer. Results: Heterozygotes for Factor V Leiden polymorphism were more frequent in the group of patients with the thromboembolic disease (16%) than in the control healthy subjects (2.9%), OR (95% CI) = 6.41 (1.81-22.8); P = 0.004. Allele and genotype frequencies of other studied polymorphisms did not differ between cases and controls. Conclusion: This study confirmed the association of factor V Leiden polymorphism with the thromboembolic disease in Croatian population

Frequency of factor II G20210A, factor V Leiden, MTHFR C677T and PAI-1 5G/4G polymorphism in patients with venous thromboembolism: Croatian case-control study

Introduction: Venous thromboembolic disease is one of the leading causes of morbidity and mortality in the developed world. Identification of hereditary factors of thrombophilia is contributing to a better understanding of the etiology and disease prevention. The aim of this study was to assess the prevalence of factor IIG20210A, factor V Leiden, MTHFR (methylenetetrahydrofolate reductase) C677T and PAI-1 (plasminogen activator inhibitor-1) 5G/4G polymorphisms in healthy Croatian subjects and patients with thromboembolism. Materials and methods: This prospective study included 100 thromboembolic patients consecutively admitted to the Intensive Care Unit, Sestre Milosrdnice University Hospital and 106 healthy subjects. Genotyping of factor IIG20210A, factor V Leiden, MTHFR C677T and PAI-1 5G/4G polymorphisms was done using melting curve analysis on Light Cycler 1.2 analyzer. Results: Heterozygotes for Factor V Leiden polymorphism were more frequent in the group of patients with the thromboembolic disease (16%) than in the control healthy subjects (2.9%), OR (95% CI) = 6.41 (1.81-22.8); P = 0.004. Allele and genotype frequencies of other studied polymorphisms did not differ between cases and controls. Conclusion: This study confirmed the association of factor V Leiden polymorphism with the thromboembolic disease in Croatian population

Continuing professional development crediting system for specialists in laboratory medicine within 28 EFLM national societies

Introduction: Continuing professional development (CPD) with corresponding crediting system is recognized as essential for the laboratory medicine specialists to provide optimal service for the patients. Article presents results of the survey evaluating current CPD crediting practice among members of European Federation of Clinical Chemistry and Laboratory Medicine (EFLM). Materials and methods: A questionnaire had been forwarded to presidents/national representatives of all EFLM members, with invitation to provide information about CPD programmes and crediting policies, as well as feedback on individual CPD categories, through scoring their relevance. Results: Complete or partial answers were received from 28 of 38 members. In 23 countries, CPD programmes exist and earn credits, with 19 of them offering access to non-medical scientists. CPD activities are evaluated in all participating countries, regardless to the existence of an official CPD programme. Among participating members with mandatory specialists’ licensing (22/28), CPD is a prerequisite for relicensing in 13 countries. Main categories recognized as CPD are: continuing education (24 countries), article/book (17/14 countries) authorship and distance learning (14 countries). The highest median score of relevance (20) is allocated to professional training, editor/authorship and official activities in professional organizations, with the first category showing the least variation among scores. Conclusions: Majority of EFLM members have developed CPD programmes, regularly evaluated and accompanied by crediting systems. Programmes differ in accessibility for non-medical scientists and impact on relicensing eligibility. Continuing education, authorship and e-learning are mainly recognized as CPD activities, although the professional training is appreciated as the most important individual CPD category