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.

Fragility spinal fractures among cirrhotic liver transplant candidates in Croatia.

INTRODUCTION: Existing data on fragility spinal fractures prevalence in liver transplant candidates are scarce and inconsistent. This may be due to other comorbidities, besides hepatic osteodystrophy (HO), that contribute to bone loss and fragility fracture prevalence in chronic liver disease (CLD). OBJECTIVES: The aim of this study was to investigate the prevalence of spinal thoracic and lumbar fragility fractures among cirrhotic, non-chronic kidney disease (CKD), non-diabetic liver transplant candidates and to explore their relationship with clinical characteristics, laboratory markers and dual-energy x-ray absorptiometry (DXA) results. MATERIAL AND METHODS: This cross-sectional observational study was conducted at Merkur University Hospital, Croatia, between February 2019 and May 2023. Adult patients with liver cirrhosis referred for liver transplantation were included. Patients with acute infection, CKD, diabetes mellitus, malignancies, inflammatory bone diseases and those on corticosteroid or antiresorptive therapy were excluded. Clinical, laboratory and radiological assessment was carried out and patients were accordingly allocated into non-fractured and fractured group for the purpose of statistical analysis. RESULTS: A total of 90 patients were included in the study. There was 123 fractures, 87 (70.7 %) in the thoracic and 36 (29.3 %) in the lumbar region. Eighty-nine (72.4 %) fractures were grade 1, 31 (25.2 %) were grade 2 and 3 (2.4 %) were grade 3. Patients in the fractured group were significantly older (p < 0.001). No significant differences between fractured and non-fractured group according to laboratory and DXA parameters were noted. Subgroup with lumbar fractures had significantly lower bone mineral density values at L1-L4 region. Statistically significant negative correlation between bone specific alkaline phosphatase (BALP) and hip total BMD (rho = -0.414, p < 0.001) and spine total BMD (rho = -0.258, p = 0.014) values was found. CONCLUSION: Present study confirmed detrimental impact of CLD and HO on bone strength. DXA measurement correlated with the presence of lumbar fragility fractures. A combination of standard X-ray imaging and DXA is needed for adequate bone evaluation in pretransplant period and BALP could be useful for detecting HO in CLD. Searching for other risk factors and implementing bone turnover markers and additional imaging techniques for bone loss evaluation in liver transplant candidates is needed.

Effect of low-flux and high-flux dialysis membrane on plasma concentrations of cardiac troponin I.

Aim: Cardiac troponin I (cTnI) concentration stability during dialysis have not been fully elucidated. The aim is to evaluate the effect of a single dialysis session on plasma cTnI. Patients & methods: From 122 consecutive anuric adult patients (75 [61.5%] men, age 27-86 years, median 67) on chronic hemodialysis blood samples for cTnI measurement were taken before and after a dialysis. Results: Dialysis had no effect on high-flux membranes (geometric means ratio = 0.99, 0.94-1.05, df 119, t = -0.19, multiplicity adjusted p = 0.847), but cTnI levels were higher after dialysis in patients on low-flux membranes (geometric means ratio = 1.14, 1.02-1.27, df 119, t = 2.59, adjusted p = 0.021). Conclusion: Dialysis session using low-flux membranes might increase the plasma cTnI.

Risk analysis of the preanalytical process based on quality indicators data.

BACKGROUND: Improving quality and patient safety in the medical biochemistry laboratory accredited according to the International Standard Organization (ISO 15189:2012) requires the patient-centered evaluation of errors based on the implementation of quality indicators (QIs) across the total testing process. Our main goal was to achieve quality improvement of the preanalytical process in an emergency laboratory which had the highest error rate using risk management principles. METHODS: Failure mode and effects analysis (FMEA) was applied to analyze predefined preanalytical QIs and score laboratory failures for the failure demerit value (FDV), probability of failure (PF) and probability of failure remedy (PFR). Based on obtained scores (on a 10-point scale) risk priority numbers (RPNs) were calculated. RESULTS: A total of five failure modes were identified in the preanalytic process. The calculated risks were "sample hemolysis" (RPN, 168),"misidentified samples" (RPN, 108),"samples clotted" (RPN, 90),"sample volume error" (RPN, 72) and "samples transported at inappropriate temperature" (RPN, 24). The activation of corrective risk-reducing measures for failure modes with RPN≥30 resulted in quality improvement with the significant decrease in reevaluated RPNs. CONCLUSIONS: The implementation of a preanalytical quality monitoring system based on observation of evidence-based QIs and patient-centered evaluation of errors through risk analysis with regular tailored education as well as implementing process improvements can effectively reduce preanalytical errors in the emergency laboratory and improve patient safety.

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

Considering the fact that the results of laboratory tests provide useful information about the state of health of patients, determination of reference value is considered an intrinsic part in the development of laboratory medicine. There are still huge differences in the analytical methods used as well as in the associated reference intervals which could consequently significantly affect the proper assessment of patient health. In a constant effort to increase the quality of patients' care, there are numerous international initiatives for standardization and/or harmonization of laboratory diagnostics in order to achieve maximum comparability of laboratory test results and improve patient safety. Through the standardization and harmonization processes of analytical methods the ability to create unique reference intervals is achieved. Such reference intervals could be applied globally in all laboratories using methods traceable to the same reference measuring system and analysing the biological samples from the populations with similar socio-demographic and ethnic characteristics. In this review we outlined the results of the harmonization processes in Croatia in the field of population based reference intervals for clinically relevant blood and serum constituents which are in accordance with ongoing activity for worldwide standardization and harmonization based on traceability in laboratory medicine.

Validation of a laboratory and hospital information system in a medical laboratory accredited according to ISO 15189.

INTRODUCTION: The aim of the study was to present a protocol for laboratory information system (LIS) and hospital information system (HIS) validation at the Institute of Clinical Chemistry and Laboratory Medicine of the Merkur University Hospital, Zagreb, Croatia. MATERIALS AND METHODS: Validity of data traceability was checked by entering all test requests for virtual patient into HIS/LIS and printing corresponding barcoded labels that provided laboratory analyzers with the information on requested tests. The original printouts of the test results from laboratory analyzer(s) were compared with the data obtained from LIS and entered into the provided template. Transfer of data from LIS to HIS was examined by requesting all tests in HIS and creating real data in a finding generated in LIS. Data obtained from LIS and HIS were entered into a corresponding template. The main outcome measure was the accuracy of transfer obtained from laboratory analyzers and results transferred from LIS and HIS expressed as percentage (%). RESULTS: The accuracy of data transfer from laboratory analyzers to LIS was 99.5% and of that from LIS to HIS 100%. CONCLUSION: We presented our established validation protocol for laboratory information system and demonstrated that a system meets its intended purpose.