Biochemia medica最新文献

Introduction: In highly stressed circumstances, such as COVID-19 pandemic, biomarkers of the vaccine-induced immunity could be especially convenient. The main aim of our study was to determine C-C motif ligand 20 (CCL20) concentration after Ad26.COV2.S vaccination in regard to more common proinflammatory molecules and its correlation with anti-SARS-CoV-2 antibody concentration. Secondly, we investigated inflammatory and immunologic profile differences between patients with and without arterial hypertension.

Materials and methods: The study included 84 subjects vaccinated with Ad26.COV2.S vaccine. Concentration of CCL20, interleukin (IL) 6, C-reactive protein (CRP) was investigated before, 7 and 14 days after vaccination and concentration of anti-SARS-CoV-2 IgG antibody 7 and 14 days after vaccination. All the markers were measured by well-established laboratory methods.

Results: There were no statistically significant changes of CCL20 and IL-6 concentration after the vaccination. The obtained results have shown statistically significant differences for CRP (P = 0.006) concentrations between 3 time points and SARS-CoV-2 IgG antibody (P < 0.001) concentrations between 2 time points. CCL20 did not correlate with IL-6, CRP or anti-SARS-CoV-2 IgG antibody concentration. Statistically significant difference for CRP (P = 0.025) concentration between 3 time points was observed in the subgroup of subjects with arterial hypertension.

Conclusions: Although our results did not show changes in CCL20 concentration after the vaccination, possibly due to the study timeframe, further investigations on chemokine profile post SARS-CoV-2 immunization could facilitate the recognition of specific patterns of response (supra- or sub-optimal) to the vaccine.

The paper aims to present the case of an asymptomatic 22-year-old man who was referred to the hematologist by laboratory experts primarily due to the extreme elevation of the erythrocyte sedimentation rate with a value of 197 mm/h. Additionally, moderate changes in laboratory parameters such as hemoglobin, leukocytes, lactate dehydrogenase, C-reactive protein, fibrinogen, and beta-2-microglobulin were recorded. Upon extensive clinical workup that included laboratory, imaging, and histological methods, a diagnosis of primary pulmonary Hodgkin's lymphoma (PPHL) was established. Primary pulmonary Hodgkin's lymphoma is a rare malignant lymphoproliferative disease that exclusively affects the lungs, and so far, only about 100 cases worldwide have been reported. The patient underwent first-line systemic chemotherapy with chest radiation and complete remission was obtained. Two years after completion of the treatment, a relapsed PPHL was clinically confirmed. Second-line chemotherapy followed by high-dose systemic chemotherapy with autologous hematopoietic stem-cell transplantation was indicated which led to complete remission and continues after 10 years from the initial diagnosis. The case demonstrates the important role of laboratory medicine experts who instantly suspected the possible laboratory-related tumor pathology and referred the patient to further hemato-oncological evaluation. This contributed to the timely diagnosis of PPHL, administration of appropriate treatment, and favorable outcome.

Laboratory medicine in sport and exercise has significantly developed during the last decades with the awareness that physical activity contributes to improved health status, and is present in monitoring both professional and recreational athletes. Training and competitions can modify concentrations of a variety of laboratory parameters, so the accurate laboratory data interpretation includes controlled and known preanalytical and analytical variables to prevent misleading interpretations. The paper represents a comprehensive summary of the lectures presented during the 35^th Annual Symposium of the Croatian Society of Medical Biochemistry and Laboratory Medicine. It describes management of frequent sport injuries and sums up current knowledge of selected areas in laboratory medicine and sports including biological variation, changes in biochemical parameters and glycemic status. Additionally, the paper polemicizes sex hormone disorders in sports, encourages and comments research in recreational sports and laboratory medicine. In order to give the wider view, the connection of legal training protocols as well as monitoring prohibited substances in training is also considered through the eyes of laboratory medicine.

Blue-green neutrophilic inclusions (BGNI), also known as "death bodies," are bright green structures observed in the cytoplasm of neutrophils or monocytes and are closely associated with acute liver failure, lactic acidosis, and other serious diseases. Some studies suggested a potential association with phagocytic lipofuscin released by damaged liver cells. The presence of BGNI typically indicated a poor prognosis. We presented two cases. Case 1 was diagnosed with novel bunyavirus infection and exhibited severe hepatic impairment and coagulation dysfunction along with the presence of BGNI in neutrophils. Despite receiving comprehensive symptomatic treatment, the patient's condition rapidly deteriorated leading to eventual demise. Case 2 had severe liver injury caused by wasp stings, and BGNI was observed. Following active treatment measures, the patient eventually achieved recovery. Throughout the disease course of case 1, there was a progressive deepening in color and increase in quantity of BGNI. Conversely, case 2 demonstrated an opposite trend. Based on the comparison of clinical outcomes and variations in color and quantity of BGNI between these two patients, it was found that an increase in the number and deepening of BGNI color corresponded to worsening condition. Conversely, a decrease in quantity and lightening of color indicated improvement. Hence, these findings suggest a possible association between changes in BGNI characteristics and prognosis.

Pseudothrombocytopenia (PTCP) is defined by the occurence of spouriously low platelet count as a consequence of in vitro platelet aggregation. It is a rare and benign artifact, not associated with any specific disorder or therapy, that becomes clinically relevant when it is not timely and reliably recognized. Thus, it may result in inappropriate clinical decisions (i.e. unnecessary further testing, misdiagnoses and potential patients' mismanagement) unavoidably compromising patient safety. The most common form of PTCP is caused by ethylenediaminetetraacetic acid (EDTA). Several approaches for the management of samples with EDTA-induced PTCP have been described in the literature. However, expert recommendations are scarce. The scope of these recommendations is to assist in achieving national harmonisation in laboratory management (i.e. detecting and reporting platelet counts) of samples with EDTA-induced PTCP. These minimal recommendations were prepared by the members of the joint working group of the Croatian Chamber of Medical Biochemists and Working group for Laboratory Hematology of the Croatian Society of Medical Biochemistry and Laboratory Medicine, and might be customized according to specific conditions (i.e. personnel and equipment) of each individual laboratory. These recommendations are primarily intended to all laboratory professionals involved in the management of samples with EDTA-induced PTCP, but also to other healthcare professionals involved in collecting samples and interpreting complete blood count results.

Introduction: Information about analyte stability is of crucial importance. The aims of this study were to determine the short- and long-term stability of synovial fluid calprotectin at various temperature conditions (4-8 °C for 7 days, - 20 °C and - 80 °C for 6 weeks).

Materials and methods: Eleven samples from patients were included in this study. The samples were promptly transported at room temperature (RT) to the laboratory immediately after arthrocentesis. Upon arrival, the samples were transferred into plastic tubes without additives and pretreated with hyaluronidase solution. After centrifugation at 1500xg for 10 minutes at RT, the baseline calprotectin concentrations were determined. Seven aliquots were stored in LoBind tubes (Eppendorf) at 4-8 °C and the calprotectin was measured every day. Six additional aliquots were stored at temperatures - 20 °C and - 80 °C and the concentration of calprotectin was measured weekly. Analysis was done using Buhlmann fCAL turbo reagent on analyzer Siemens Atellica Solution (Siemens Healthcare, Erlangen, Germany). Data were analyzed by Microsoft Excel and MedCalc statistical software. The percentage difference (PD%) was calculated. The maximum permissible difference (MPD) was 9.1% for PD%.

Results: The PD% with the corresponding 95% confidence intervals were inside the predefined MPD. The instability equations and correlation coefficient for storage temperatures were PD% = 0.1644 x time (day), r = 0.06, P = 0.614 for 4-8°C, PD% = 0.5190 x time (week), r = - 0.22, P = 0.080 for - 20°C, and PD% = 0.1316 x time (week), r = 0.08, P = 0.545 for - 80°C.

Conclusions: The calprotectin in the synovial fluid is stable when stored long-term for 6 weeks at - 20 °C or at - 80 °C or short-term (7 days) at 4-8 °C.

Researchers and practitioners are typically familiar with descriptive statistics and statistical inference. However, outside of regression techniques, little attention may be given to questions around prediction. In the current paper, we introduce prediction intervals using fundamental concepts that are learned in descriptive and inferential statistical training (i.e., sampling error, standard deviation). We walk through an example using simple hand calculations and reference a simple R package that can be used to calculate prediction intervals.

Introduction: Thyroid-stimulating hormone (TSH) is a glycoprotein secreted by the anterior pituitary gland and is regulated by negative feedback from the serum free thyroid hormones. In this study we aimed to quantitate the relative bias caused by calibration drifting as seen in our TSH Levey-Jennings quality control (QC) charts and assess the magnitude of bias on patients' samples.

Materials and methods: In the period from October 2021 to August 2022 we looked at the QC results of ten 28-days' calibration time intervals and calculated relative bias compared to the mean. For each time interval the mean from three QC points before and after calibration was calculated. The average from 10 pre- and post-calibration means was calculated and the relative bias, pre- and post-calibration, was then calculated. We used 5 patient samples with low, normal and high TSH concentrations and calculated relative bias pre- and post-calibration. The allowed relative bias for TSH is ± 6.7%.

Results: At both QC levels, with the respective means of 5.14 mIU/L (coefficient of variation, CV% = 3.1%) and 27.80 mIU/L (CV% = 3.2%) had their respective relative bias - 8.2% and - 7.9%. The patient samples with low (0.586 mIU/L), normal (2.89 mIU/L and 5.19 mIU/L) and high (20.5 mIU/L and 39.8 mIU/L) TSH had - 4.1%, - 4.0%, - 3.5%, - 5.1% and - 4.1%, respectively.

Conclusion: Even though the relative bias exceeded allowable criteria for the QC samples, this was not manifested on the patients' samples.

Alkaptonuria is characterized by the accumulation of homogentisic acid which causes dark coloration of urine upon standing, ochronosis, and arthritis. A 4-year old child was referred to our pediatric nephrologist with hyperoxaluria and a history of unexplained pink-to-brown discolouration of his diapers associated with a brown-staining of clothes and skin since he was six months old. He had no other symptoms and his past medical history only included minor child illnesses. His 11-month-old brother had the same dark discoloration of his diapers. Laboratory testing on a spot urine sample showed hyperoxaluria and nephrotic range proteinuria with low creatinine and normal albumin concentrations. Considered causes were hyperoxaluria, alkaptonuria, interfering substance, adulteration. The further diagnostic work-up revealed increased homogentisic acid in urine, compatible with alkaptonuria. Urinary creatinine and total protein measurements on Roche Cobas were, respectively, falsely decreased and increased in the presence of homogentisic acid. The false-low creatinine resulted in an elevated oxalate/creatinine ratio. Alkaptonuria can cause a false increase of results expressed per creatinine and should be excluded in case of an unexplained marked increase of urine total protein without a concomitant increase of albumin.

Introduction: This study aimed to determine autoverification rules for routine glycated hemoglobin (HbA1c) analysis based on high-performance liquid chromatography (HPLC) principle. Laboratory information system (LIS) and Bio-Rad D-100 Advisor software (Bio-Rad, Hercules, USA) with graphics recognition function were carriers for the autoverification system.

Materials and methods: A total of 105,126 HbA1c results, including 98,249 HbA1c matching fast plasma glucose (FPG) results of real-world data from May 2019 to June 2020, were collected to determine autoverification rules including flags, delta checks, reporting limits, and logical rules. The validation database was composed of 48,045 HbA1c results and 41,083 matching FPG results. Autoverification passing rate and the reduction of turnaround time (TAT) were evaluated.

Results: Four autoverification systems (A, B, C, D) were established by two types of delta check rules, 28 flags, one reporting limits, and two kinds of logical rules. The autoverification passing rates were 80.6%, 78.8%, 83.7%, and 81.3%, and the average time saved in TAT were 117.5 min, 116.7 min, 121.1 min, and 121.7 min, respectively.

Conclusions: Autoverification system C was the optimal one. Application of distribution of FPG corresponding to HbA1c groups had better performance as logical rules. Established HbA1c autoverifcation system shortened the auditing report time and improved work efficiency.