Scandinavian Journal of Clinical & Laboratory Investigation最新文献

Capillary blood is often used for dried blood spot samples in metabolic screening tests. This study's objective is to examine the amino acid and acylcarnitine levels in the commonly used sampling types from the same subjects and compare the findings with capillary whole blood samples as the reference. Thirty adult patipicants' blood samples were collected into four different tubes: citrated tubes, serum separating tubes, heparin tubes, and EDTA tubes, respectively and additionally into the syringe. 50 μL blood from each tube and syringe was absorbed onto filter papers. Additionally, capillary whole blood taken from each person's fingertip was absorbed onto the filter paper. All measurements were performed with flow-injection analysis tandem mass spectrometry. In the pairwise comparison of fingertip group and other groups, almost all results were different from the reference group (p < 0.05), except for glutamine and methionine for amino acid analysis. The difference in acylcarnitine levels is not as obvious as in amino acid levels. If other sampling types are used for metabolic screening instead of capillary whole blood, it may lead to low results, especially in amino acid measurements. Additionally, cut-off values should be interpreted, taking into consideration the sampling type, and laboratories should be informed about the sampling type used.

Myeloid cell overgrowth in polycythemia vera (PV) is identified by a clonal disorder. The mutation in the Janus tyrosine kinase 2 (JAK2) gene known as V617F has been demonstrated to be responsible for the molecular development of the illness. This study investigates how frequently the JAK2 V617F mutation occurs and its association with erythropoietin (EPO) and hematological parameters in PV patients. Two hundred and forty-five patients who presented to the genetic outpatient clinic with a prediagnosis of PV were included in this study. Blood samples from all patients were screened for the G-T point mutation (V617F) in the JAK2 gene on chromosome 9 by allele-specific polymerase chain reaction (PCR). In addition, EPO levels, biochemical and hematological parameters of the patients were analyzed. JAK-2 mutation was detected in 28.9% (71) of patients diagnosed with PV. The mean age of the JAK2 V617F positive group was 64.09 ± 13.66 years, negative group was 66.62 ± 16.60 years. No statistically significant difference was found between the groups in terms of age and gender. When laboratory parameters were analyzed, ferritin, Fe, MCV, MCH, MCHC and EPO values were found to be lower in the JAK2 V617F positive group compared to the negative group, while RBC, RDW, MPV, PLT, HGB and UIBC values were found to be higher. The main observation of the study was that the JAK2 V617F mutation was present in 71 out of 215 PV patients (28.98%), confirming the observation of lower EPO levels in PV patients, and the results of the study are in close agreement with previous studies.

Placental growth factor (PLGF) dynamics exhibit significant variations between singleton and twin pregnancies, necessitating distinct clinical reference intervals. This large study established and validated trimester-specific reference intervals (RIs) for maternal PLGF levels in 16,877 singleton and 940 twin pregnancies, with subsequent evaluation of their predictive accuracy for pregnancy complications. Key findings revealed that twin pregnancies demonstrated elevated median PLGF concentrations compared to singletons from 1st (≤13 weeks) through 2nd-late (22-27 weeks), followed by a reversal of this trend in the 3rd-early (28-32 weeks) with significantly lower PLGF levels persisting until delivery. Chorionicity did not influence PLGF levels in twins (p > 0.05). Using the 2.5th-97.5th percentile ranges, gestational age-specific RIs were defined for both cohorts. In validation cohorts comprising pregnancies complicated by preeclampsia (PE), fetal growth restriction (FGR), placental abruption (PA), or postpartum hemorrhage (PPH), PLGF thresholds were stratified relative to lower reference limits (LRLs). PLGF concentrations below 80%, 100%, and 120% of LRLs were strongly associated with elevated risks for all studied complications. Adjusted logistic regression models demonstrated a dose-dependent relationship, with adjusted odds ratios (aOR) escalating inversely to PLGF thresholds: aOR = 3.2 (95% CI: 2.5-4.1) at 120% LRL, increasing to aOR = 8.7 (95% CI: 6.3-12.0) at 80% LRL. These findings confirm that trimester-specific PLGF RIs effectively stratify pregnancy risks, with sub-LRL values serving as independent predictors of adverse outcomes. This established RIs enhance obstetric risk assessment frameworks, supporting PLGF integration as a complementary biomarker for targeted monitoring and early intervention in both singleton and twin pregnancies.

Pneumatic tube systems (PTS) are routinely used in many hospitals for transporting collected body fluid samples and to reduce turnaround time. However, their use for transport of CSF is not widespread, in part due to ambiguous or non-existing data regarding possible impact on sample stability caused by PTS. This study investigates the effect of PTS transport on cell counts in CSF as well as on haemolysis. No statistical differences were observed on cell count for erythrocytes, leukocytes, lymphocytes, neutrophils, or monocytes as well as on haemolysis measured as absorbance at 415 nm. Therefore, it should be possible to use a PTS to transport CSF for these analyses.

Introduction: Treatment with infliximab (IFX) and adalimumab (ADL) are used in a range of inflammatory diseases. Measurement of drug levels is warranted, but can be challenged by turn-around-times at the laboratories. Consequently, point-of-care testing (POCT) technology is becoming increasingly relevant. We evaluated the precision and comparability of results obtained with ProciseDx (Biosynex) when used in outpatient gastroenterology clinics monitoring IFX and ADL.

Materials and methods: In this prospective multi-center study, capillary and venous blood samples were collected by trained nurses from patients with inflammatory bowel disease on maintenance therapy with either IFX or ADL. Fourteen different nurses performed blood sampling and IFX measurements using ProciseDx on 64 patients, while 11 different nurses performed ADL measurements on 48 patients. Venous samples were sent to the laboratory for routine testing using Promonitor ELISA kit on a Triturus (Grifols).

Results: Across all patients and all sites, a variation of 18.9% and 11.4% was observed for IFX and ADL measurements, respectively. Peak variance was in the 5-10 mg/L IFX concentration range, while peak variance for ADL measurements was above 12 mg/L. Compared to the routine ELISA, the r-value was 0.82 for IFX with a mean total deviation of 2.10 mg/L (27.1%). For ADL, the r-value was 0.91 with a mean total deviation of 2.93 mg/L (39.7%).

Conclusion: We find the efficacy and accuracy of the ProciseDx acceptable, but when performed by non-laboratory personnel, the differences to routine measurements are considerable and could have a clinical impact. Clinical implementation would at least require reevaluation of the therapeutic intervals.

The screening test for early detection of α-thalassemia is essential in effective management and genetic counseling. The immunochromatographic (IC) strip test is widely used for α-thalassemia screening due to its simplicity and high sensitivity. This study explores the causes of false-positive IC strip results in subjects with HbF >5% who tested negative for common α⁰-thalassemia --^SEA, --^Thai and --^{Chiang Rai} type deletions. Fifty whole blood samples were tested using IC strips, and resulting positive samples were retested with washed red blood cells (RBCs) and plasma. Follow-up testing included molecular analysis to detect common hemoglobinopathies in washed RBCs, including α⁺-thalassemia -α^3.7 and -α^4.2 deletions, Hb Constant Spring (CS), Hb Quong Sze (QS) and Hb Westmead (WM), as well as antinuclear antibodies (ANAs) screening in plasma. Ten of 50 EDTA whole-blood samples tested positive using the IC strip test, with eight showing positivity in plasma and seven in washed RBCs. Among them, one plasma-positive sample was also positive for ANA, suggesting potential antibody interference. Of the seven RBC-positive samples, three had common hemoglobinopathies: two with the -α^3.7 deletion and one with Hb CS. The remaining four RBC-positive cases had no detectable mutations but were infants under three months of age. Since most false positives occur in infants under 8 months, caution is recommended when testing this age group. Additionally, washing red cells can help reduce antibody interference. Further molecular studies, such as Sanger sequencing, MLPA and NGS, should be initiated in cases without obvious causes.

Biochemical tests are crucial in acute patient care, and the validity of the results is important. We aimed to evaluate extreme results reported in a routine hospital laboratory and to review patient characteristics. This is a retrospective cohort study of extreme laboratory results reported at the Department of Clinical Biochemistry, Aalborg University Hospital, Denmark (2022-2024). For six common analytes (sodium, potassium, creatinine, calcium, phosphate, and magnesium), the most extreme low (n = 25) and high (n = 25) results were identified. Electronic health records of 284 unique patients were reviewed to determine pathophysiological causes, pre-analytical errors, clinical course, and 7-day survival. Among 5,794,014 biochemical test results, 300 extreme results (0.005%) were identified, with 261 (87.0%) being compatible with a pathophysiological cause, and 39 (13.0%) being caused by a pre-analytical error. For high results, renal failure was the predominant cause (54.1%), particularly affecting creatinine, phosphate, and potassium. For low results, low creatinine was caused by muscle atrophy, while for other analytes, the most common causes were malnutrition, alcoholism, sepsis, diarrhea/emesis, and diuretics. The 7-day survival was lower for patients with extremely high results (77.4%) compared to low (94.5%). In conclusion, in a routine hospital laboratory, extreme biochemical test results were often pathophysiological, with pre-analytical errors accounting for around 10% of the reported results. Survival was generally high and patients with extremely low results had higher survival compared to those with extremely high results. Results inform the laboratory's decision-making on the handling and release of extreme biochemical results.

In this study, we used manual microscopy as the gold standard, and compared the analytical and clinical performance of EH-2090 and UF-5000 to evaluate their application characteristics in daily clinical practice. Results show the EH-2090 has comparable analytical performance to Sysmex UF-5000. In clinical performance, the EH-2090 shows better counting accuracy for urine formed elements except bacteria. Besides, the EH-2090 could provide more accurate assessment especially in samples with yeast cells, crystals and dysmorphic red blood cells.

There is limited evidence regarding the role of circulating neutrophil gelatinase-associated lipocalin (NGAL) in patients admitted with complications of cirrhosis. This prospective cohort study evaluated 161 adult patients hospitalized for acute decompensation (AD) of cirrhosis, with serum samples collected within 48 h of admission. The aim was to investigate the association between NGAL levels, acute kidney injury (AKI), and patient outcomes. Sixty patients presented with AKI at admission. Serum NGAL was independently associated with AKI (OR 1.019, 95% CI 1.012-1.027; p < 0.001), with levels increasing across AKI stages: no AKI (94.24 µg/L), stage 1 (179.20 µg/L), stage 2 (235.50 µg/L), and stage 3 (257.85 µg/L; p < 0.001). Hepatorenal syndrome (HRS) was associated with significantly higher NGAL compared to pre-renal AKI (259.70 vs. 179.30 µg/L; p = 0.002). NGAL predicted HRS with an AUROC of 0.837 (±0.064), with a negative predictive value of 94% for NGAL < 215.00 µg/L. It also predicted AKI reversibility, with an AUROC of 0.829 (±0.061) and a positive predictive value of 98% for NGAL < 242.00 µg/L. Furthermore, NGAL independently predicted 30-day mortality, with a survival probability of 90.8% for NGAL < 160 µg/L and 66.7% for NGAL ≥ 160 µg/L (p < 0.001). These findings support the clinical utility of circulating NGAL as a biomarker reflecting AKI phenotype and disease severity in patients acutely hospitalized for cirrhosis-related complications, with prognostic relevance.