Biochemia medica最新文献

Proper preanalytical handling of blood samples is critical to ensure the reliability of laboratory results, particularly in patients undergoing hemodialysis, where biochemical monitoring is essential for assessing dialysis adequacy and guiding treatment decision. We reported three cases of abnormal post-dialysis gel separator flotation in blood collection tubes from patients undergoing hemodiafiltration: in each case, the gel migrated to the top of the tube, with plasma trapped below and blood cells remaining at the bottom. Marked hyperproteinemia and hypercalcemia were observed in the plasma, inconsistent with the patient's clinical status and pre-dialysis values. These findings raised suspicion of a preanalytical error potentially associated with the hemodialysis procedure. On-site investigations conducted in collaboration with the dialysis center for four additional patients, combined with a better understanding of the principles of hemodiafiltration and the potential sampling sites, confirmed that the gel migration anomaly was secondary to unsuitable sampling from the venous line (outflow line) of the dialysis circuit instead of the arterial one (inflow line). In conclusion, we highlighted the critical role of adhering to the appropriate sampling site when performing post-dialysis blood tests: the arterial line was identified as the appropriate site for post-dialysis blood sampling, while the venous line should be reserved exclusively for infusion or reinjection purposes and must never be used for blood collection at the end of dialysis.

This commentary discusses the prognostic relevance of leukocyte telomere length and paraoxonase-1 activity in small-cell lung cancer (SCLC) patients undergoing chemotherapy. It emphasizes the importance of integrating telomere biology and oxidative stress assessment in prognostic modeling. The discussion also considers the modifying effects of lifestyle, treatment regimens, and genetic background, advocating for research that combines clinical, biochemical, and molecular data to enhance prognostication in SCLC.

Introduction: The Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) Key Incident Monitoring and Management EQA Program (KIMMS) aims to monitor the laboratory quality system's pre- and post-analytical phases. The purpose of this paper is to describe the most common incidents from 2024.

Materials and methods: The KIMMS program has four surveys a year, collecting data from the previous three months, with preanalytical and postanalytical incident reporting of 35 incident types. Participants are asked to capture the number of episodes and the number of incidents per quarter of the year.

Results: The four 2024 surveys received an average of 111 responses, with 55,329,998 episodes recorded and 1,496,708 incidents identified. The findings from the 2024 program are that the incident "No specimen received" appears to have the highest 80th percentile across the patient sources. The commonest site of error is the Emergency Department (ED), with an 80th percentile overall.

Conclusions: The KIMMS data provide valuable, regular and reproducible benchmarking data for the pre- and post-analytical phases of the total testing cycle.

Introduction: This study established laboratory and trimester specific indirect reference intervals (RIs) for thyroid stimulating hormone (TSH).

Materials and methods: A retrospective observational study was performed at a tertiary-care laboratory's hospital during 12 months. Between February 2023 and February 2024, TSH results from 2166 women in their first trimester of pregnancy were retrieved. Only outpatients coming from primary care were included in the study. After applying exclusion and outlier criteria, TSH results from 1300 patients were analyzed to establish new RIs using the 2.5th and 97.5th percentiles by the non-parametric percentile method. These RIs were verified by an indirect method analyzing 486 TSH results from a cohort of pregnant women that were extracted from April to June 2024, and a direct prospective study of 28 pregnant women from a primary care center. All TSH tests were measured using a Cobas 8000 e801 system (Roche, Basel, Switzerland).

Results: The TSH RIs were 0.60-4.33 mIU/L. Both verification methods met the requirements of the CLSI guidelines.

Conclusions: The indirect method could be used to establish and verify local RIs for TSH in first trimester pregnant women. This may reduce misclassification of pregnant women undergoing thyroid function tests.

Introduction: Prostate-specific antigen (PSA) can circulate bound to extracellular vesicles (EVs) and its measurement (ev-PSA) can be useful in prostate cancer. Although not designed with that purpose, total PSA assays react with ev-PSA. We evaluated the analytical performance of several total PSA assays in ev-PSA quantification and the impact of ev-PSA on total PSA measurement.

Materials and methods: Extracellular vesicles were isolated from 83 serum samples from prostate cancer patients by size exclusion chromatography or ultracentrifugation. PSA was quantified in serum, EVs, International Standard for PSA 17/100 from the World Health Organization (WHO IS 17/100) and exosomes from lymph node carcinoma of the prostate (LNCaP) cell line, using commercial immunoassays (Elecsys, Atellica, Immulite, Liaison and Kryptor).

Results: Nanoparticle tracking analysis showed that the WHO IS 17/100 contains significantly less EVs than serum (P < 0.001). The sensitivity to detect ev-PSA followed this order: Elecsys ~ Atellica > Immulite > Liaison > Kryptor. Ev-PSA could be detected in all serum samples with Elecsys and Atellica, but not with Immulite (87.8%), Liaison (58.5%) or Kryptor (48.8%). Bland-Altman analysis showed a proportional bias in ev-PSA quantification between Elecsys and other methods. Addition of ev-PSA to serum samples caused a proportional bias in PSA measurement between Elecsys and Immulite methods, with a relationship (r² = 0.99; P < 0.001) between ev-PSA and the difference in total PSA concentration between both methods.

Conclusions: While ev-PSA can be measured using commercial kits, notable differences exist between methods, which could lead to potential discrepancies in serum total PSA results across various assays.

Introduction: Lipoprotein(a) (Lp(a)) is an independent cardiovascular risk factor, primarily determined by genetic factors. This study assessed Lp(a) concentrations in presumably healthy subjects and evaluated its association with age, sex, and cardiometabolic risk factors.

Materials and methods: The study included presumably healthy 1046 adults and 276 children. Laboratory parameters: lipid profile, Lp(a), apolipoprotein B (apoB), glucose, HbA1c, C-reactive protein and creatinine were measured. Contributions of Lp(a)-apoB to apoB (%Lp(a)/apoB) and of Lp(a)-cholesterol to LDL-cholesterol (%Lp(a)-C/LDL-C) were calculated.

Results: Lipoprotein(a) concentrations were significantly higher in adults than in children (P = 0.014) and in women than in girls (P = 0.003), but showed no overall sex differences. In women, Lp(a) was higher after age 50, while in men a slight rise occurred after age 60. Lipid indices %Lp(a)/apoB and %Lp(a)-C/LDL-C declined in men until their 40s and was higher after 50 in both sexes. In a multivariable logistic regression model increased LDL-C concentration was a significant predictor of Lp(a) ≥ 0.30 g/L in women (odds ratio, OR = 1.77; P = 0.021) and children (OR = 2.83; P = 0.009). Boys had twofold higher probability of Lp(a) ≥ 0.30 g/L than girls (OR = 2.17; P = 0.024).

Conclusions: Lipoprotein(a) concentrations increase with age, especially after 50 in women and 60 in men, and are significantly associated with LDL-C. Rising %Lp(a)/apoB and %Lp(a)-C/LDL-C alongside falling apoB and LDL-C suggest greater atherogenicity in older individuals, particularly men. These findings support including Lp(a) in lipid profile for better cardiovascular risk assessment.

Effect size measures are important complements to P values, providing information about the magnitude and practical relevance of research findings. While widely discussed in the context of parametric tests, effect size estimation for nonparametric tests remains less explored. This article reviews standardized effect size measures applicable to four common nonparametric tests: Mann-Whitney, Wilcoxon signed-rank, Kruskal-Wallis, and Friedman. Commonly suggested classifications for these effect sizes are also discussed. This article aims to support researchers in reporting and interpreting effect sizes more effectively in nonparametric contexts.

Introduction: Differentiating between malignant pleural effusion (MPE) and tuberculous pleural effusion (TPE) remains challenging in clinical practice. The cancer ratio plus (CR+), a potential diagnostic tool calculated as serum lactate dehydrogenase/(pleural adenosine deaminase x pleural lymphocyte percentage) has emerged to address this diagnostic challenge. This scoping review maps the available evidence on its diagnostic performance.

Materials and methods: We conducted a systematic search of PubMed, Scopus, and Web of Science databases from inception to April 2025. Eligible studies assessed the accuracy of CR+ in distinguishing MPE from TPE. Data on study design, cut-off values, sensitivity, specificity, area under the curve (AUC), and likelihood ratios were extracted and synthesized narratively.

Results: Six studies comprising 881 patients were included. Reported cut-off values varied widely (5.7 - 41.0), as did sensitivity (74.3 - 97.6%) and specificity (36.6 - 94.1%). Most studies, however, reported good discriminatory power with AUC values generally above 0.80. The highest diagnostic accuracy was observed in one study, which reported a sensitivity of 97.6%, a specificity of 94.1%, and an AUC of 0.86. Differences in cut-off thresholds, study populations, local tuberculosis epidemiology, and laboratory methodology (particularly lymphocyte quantification) likely contributed to this heterogeneity.

Conclusions: The CR+ appears promising as a non-invasive tool using routine parameters for differentiating MPE from TPE, but diagnostic performance varies across settings. The heterogeneity in optimal cut-off values highlights the need for local validation before clinical adoption. Future research should standardize methodology and assess its impact on decision-making and patient outcomes.

Introduction: The hormonal interplay between the mother and the fetal-placental unit may influence the mode of delivery. This study aimed to investigate the association between maternal peripartal serum concentrations of sex hormone-binding globulin (SHBG) and 10 steroid hormones with delivery outcomes.

Materials and methods: This observational study included 171 healthy pregnant women with spontaneous onset of labor: 117 had vaginal delivery and 54 underwent urgent cesarean section (C-section). Serum concentrations of aldosterone, androstenedione, cortisol, cortisone, corticosterone, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), 17-hydroxyprogesterone, progesterone, and total testosterone were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS), while free testosterone was calculated. Sex hormone-binding globulin was measured by chemiluminescent microparticle immunoassay. Group differences were tested with the Mann-Whitney U test, and associations with delivery mode were assessed by logistic regression and receiver operating characteristic (ROC) analysis.

Results: Compared with the vaginal delivery group, women who underwent urgent C-section had significantly lower serum concentrations of SHBG, corticosterone, cortisol, aldosterone, progesterone, 17-hydroxyprogesterone, DHEA, DHEAS, and free testosterone (all P < 0.001). In multivariate logistic regression, aldosterone (odds ratio, OR 0.11, 95% CI 0.04 to 0.27, P < 0.001) and DHEAS (OR 0.74, 95% CI 0.58 to 0.94, P = 0.011) were independently associated with delivery mode. ROC analysis showed that aldosterone > 0.9 nmol/L predicted vaginal delivery with AUC 0.874, sensitivity 88%, and specificity 77%.

Conclusions: Low maternal aldosterone concentrations showed the strongest association with urgent C-section, suggesting that aldosterone may play a protective role in successful vaginal delivery.

Introduction: Cardiac biomarkers may help diagnose and monitor different neonatal conditions, but their concentrations are still underexplored in common pathologies diagnosed within the first day. This study compared N-terminal pro b-type natriuretic peptide (NT-proBNP), high sensitivity troponin I (hs-TnI), creatine kinase (CK), and its isoenzyme creatine kinase-myocardial band (CK-MB) concentrations and activities, measured within the first 24 hours (h) postpartum, between the healthy term neonates and those with jaundice, perinatal infection, transient neurological abnormalities (TNA), and heart ultrasound abnormalities.

Materials and methods: The study included 100 term newborns, whose cardiac biomarkers' concentrations were determined from the serum within 24 h postpartum on the Alinity ci analyzer (Abbott, Chicago, USA). The Mann-Whitney and Kruskal-Wallis tests, performed in SPSS Statistics v. 25.0 (IBM Corp., Armonk, USA), were used to test the significance of differences between the study groups, with P < 0.05 indicating significance.

Results: Within first 24 h postpartum healthy newborns had significantly higher CK activities compared to those with jaundice (P = 0.047), perinatal infection (P = 0.012), or combination of both (P = 0.017). Lower CK activities were demonstrated in perinatal infection compared to TNA (P = 0.041). Other biomarkers' concentrations did not differ between the study groups. No significant differences were found in cardiac biomarkers' concentrations regarding gender or heart ultrasound findings.

Conclusions: During the first 24 h postpartum, only CK activities differed between healthy newborns and those with the common pathologic conditions, being lower in the newborns with jaundice and/or infection. Analogous differences were present between newborns with infection and those with TNA.