Standardization in laboratory medicine: Adoption of common reference intervals to the Croatian population

Outbreak of hantavirus disease caused by Puumala virus, Croatia, 2021

In 2021, a large outbreak of hantavirus disease (HAVID) in Croatia with 334 notified cases coincided with a COVID-19 wave and included patients from areas previously not considered endemic, challenging HAVID recognition and patient management. We analysed clinical and epidemiological data on all 254 patients with HAVID treated in the Clinical Hospital Center Rijeka (CHC Rijeka) between February and November 2021. Most patients (n = 246; 96.9%) had antibodies against Puumala virus, 212 (83.5%) were residents of endemic areas for HAVID, 93 (36.6%) reported occupational exposure and 86 (33.9%) had observed rodents or rodent excreta. Thirty-seven (14.6%) patients were not notified to the public health authorities. Most patients (n = 177; 69.7%) were male. The median age of the patients was 43 years (range: 17-79 years) in males and 54 years (range: 14-77 years) in females. More severe courses of disease were observed in males aged < 45 years than in older males and females of any age (OR = 2.27; 95% CI: 1.21-4.24; p < 0.005). Measures to prevent exposure, early detection and notification of cases and close collaboration between primary and secondary healthcare teams with public health personnel are essential to improve surveillance and prevent hantavirus outbreaks.

CLSI-based verification and de novo establishment of reference intervals for common biochemical assays in Croatian newborns

Introduction

This study aimed to examine whether the Canadian Laboratory Initiative on Pediatric Reference Intervals (CALIPER) reference intervals for 19 commonly used biochemical assays (potassium, sodium, chloride, calcium, magnesium, inorganic phosphorous, glucose, urea, creatinine, direct and total bilirubin, C-reactive protein (CRP), total protein, albumin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP) and lactate dehydrogenase (LD)) could be applied to the newborn population of one Croatian clinical hospital.

Materials and methods

Reference interval verification was performed according to the CLSI EP28-A3c guidelines. Samples of healthy newborns were selected using the direct a posteriori sampling method and analyzed on the Beckman Coulter AU680 biochemical analyzer. If verification wasn't satisfactory, further procedure included de novo determination of own reference intervals by analyzing 120 samples of healthy newborns.

Results

After the first set of measurements, 14/19 tested reference intervals were adopted for use: calcium, inorganic phosphorous, glucose, urea, creatinine, total bilirubin, CRP, total protein, albumin, AST, ALT, GGT, ALP and LD. A second set of samples was tested for 5 analytes: potassium, sodium, chloride, magnesium and direct bilirubin. The verification results of the additional samples for sodium and chloride were satisfactory, while the results for potassium, magnesium and direct bilirubin remained unsatisfactory and new reference intervals were determined.

Conclusions

The CALIPER reference intervals can be implemented into routine laboratory and clinical practice for the tested newborn population for most of the analyzed assays, while own reference intervals for potassium, magnesium and direct bilirubin have been determined.

Indirect determination of biochemistry reference intervals using outpatient data

The aim of this study was to determine reference intervals in an outpatient population from Vall d'Hebron laboratory using an indirect approach previously described in a Dutch population (NUMBER project). We used anonymized test results from individuals visiting general practitioners and analysed during 2018. Analytical quality was assured by EQA performance, daily average monitoring and by assessing longitudinal accuracy between 2018 and 2020 (using trueness verifiers from Dutch EQA). Per test, outliers by biochemically related tests were excluded, data were transformed to a normal distribution (if necessary) and means and standard deviations were calculated, stratified by age and sex. In addition, the reference limit estimator method was also used to calculate reference intervals using the same dataset. Finally, for standardized tests reference intervals obtained were compared with the published NUMBER results. Reference intervals were calculated using data from 509,408 clinical requests. For biochemical tests following a normal distribution, similar reference intervals were found between Vall d'Hebron and the Dutch study. For creatinine and urea, reference intervals increased with age in both populations. The upper limits of Gamma-glutamyl transferase were markedly higher in the Dutch study compared to Vall d'Hebron results. Creatine kinase and uric acid reference intervals were higher in both populations compared to conventional reference intervals. Medical test results following a normal distribution showed comparable and consistent reference intervals between studies. Therefore a simple indirect method is a feasible and cost-efficient approach for calculating reference intervals. Yet, for generating standardized calculated reference intervals that are traceable to higher order materials and methods, efforts should also focus on test standardization and bias assessment using commutable trueness verifiers.

International Society on Thrombosis and Haemostasis core curriculum project: Core competencies in laboratory thrombosis and hemostasis

BACKGROUND

Laboratory analyses of blood samples are essential for diagnostics and therapy monitoring of patients with bleeding and thromboembolic diseases. Following publication of the core curriculum for clinical thrombosis and hemostasis, the International Society on Thrombosis and Haemostasis (ISTH) recognized that thrombosis and hemostasis laboratory specialists require distinct competencies that differ from medical doctors working clinically with patients. To address this gap the ISTH formed a working group of international hemostasis and thrombosis laboratory specialists to develop an evidence-based core curriculum for laboratory specialists.

OBJECTIVE

This research sought consensus from the international community on core competencies required for laboratory specialists in thrombosis and hemostasis.

METHODS

A draft list of 64 competencies was developed and an online stakeholder survey was circulated electronically to 15 302 ISTH members and contacts in the wider international community. The results were analyzed and used to develop the final approved core curriculum.

RESULTS

Three hundred and thirty responses contained meaningful data, with broad international representation of specialists. No draft competencies were excluded, and 58 were rated as "does" or "shows how." The Leik measure of consensus for most competences was "moderate" (n = 30) or "fair" (n = 32).

CONCLUSIONS

The development of an international core curriculum for laboratory specialists provides a foundation for the development and enhancement of education and quality management of the laboratory. Although there is no formal designation for laboratory specialists, international governing bodies and regulatory organizations are encouraged to consider the diagnostic core curriculum for development and accreditation of more standardized educational programs and formal assessment across jurisdictions.