Factor V G1691A has an important role in susceptibility to arterial ischemic stroke, both in the perinatal/neonatal period and in childhood, as well as transient ischemic attacks. A minor impact of human platelet alloantigen polymorphisms suggests that platelet glycoprotein polymorphisms may increase the risk of transient ischemic attacks and migraine, but this should be confirmed in larger studies.

ACL TOP is a fully automated coagulation analyzer, designed for simultaneous measurement of routine and special coagulation parameters. We evaluated analytical and technical performance characteristics of the coagulation system composed of the ACL TOP analyzer and HemosIL reagent group for the determination of routine clotting (PT, APTT, fibrinogen, FVII, and FVIII), chromogenic (protein C) and immunological assays (FXIII antigen). Within run and between run CVs ranged from 0.9% to 7.7% and from 2.0% to 14.8% respectively. The obtained CVs for imprecision of calibration curves were <5% of PT and <7% for fibrinogen. The method comparison study showed good correlation between results obtained on the ACL TOP and BCS/BCT analyzers, with correlation co-efficients ranging from 0.709 to 0.955, but with significantly different results for PT INR, APTT, fibrinogen and protein C, and wide dispersion of differences observed in difference plots for most assays. Despite good correlation and agreement for FVIII, problems in measuring FVIII<10% were encountered. The effective througput for the ACL TOP and BCS was 151 and 212 PT/APTT/fibrinogen tests per hour, respectively. Although the ACL TOP is designed to run multiple assays on a large number of samples, software limitations make the instrument suitable rather for mid-sized laboratories.

Despite the identification of a wide range of inherited and acquired risk factors for arterial ischemic stroke (AIS) in children, genetic risk factors are incompletely characterized and may vary among different populations. We investigated the role of individual and combined inherited prothrombotic and intermediate-risk factors in 73 children with perinatal (n = 35) and childhood AIS (n = 38) and 100 age- and sex-matched controls. Ten polymorphisms in 8 candidate genes encoding coagulation and fibrinolytic proteins (factor V [FV] Leiden, FV HR2, factor II [FII] G20210A, β-fibrinogen [β-FBG]-455G>A, factor XIII [FXIII]-A p.Val34Leu, plasminogen activator inhibitor 1 4G/5G), homocysteine metabolism (methylenetetrahydrofolate reductase [MTHFR] C677T, MTHFR A1298C), and intermediate-risk factors (angiotensin-converting enzyme I/D, apoE ∊2-4) were detected using a multilocus genotyping assay. Allele-specific polymerase chain reaction was used for the determination of human platelet alloantigens (HPA-1, HPA-2, HPA-3, and HPA-5). Factor V Leiden was associated with an increased risk of AIS (odds ratio [OR]: 4.72, 95% confidence interval [CI]: 1.22-18.27) and perinatal AIS (OR: 8.29, 95% CI: 1.95-35.24). Human platelet antigen-3b allele carriers had a 2-fold lower risk of AIS (OR: 0.51, 95% CI: 0.26-0.98) and perinatal AIS (OR: 0.40, 95% CI: 0.18-0.92). A 2.21-fold increased risk of childhood AIS (95% CI: 1.03-4.73) was identified in FXIII-A Leu34 allele carriers. Combined FV Leiden/FV HR2, FV Leiden/MTHFR A1298C, FV Leiden/MTHFR C677T/MTHFR A1298C, and FV Leiden/FV HR2/MTHFR A1298C heterozygosity was identified in children with AIS but not in controls, which revealed a statistically significant difference. This case-control study shows that besides already documented association between FV Leiden and AIS, other previously unreported polymorphisms (FXIII-A p.Val34Leu, HPA-3) and several genotype combinations that always include heterozygous FV Leiden can be related to AIS in Croatian population.

Plasma samples stored both at RT and 4°C for 24 hours are acceptable for additional PT, Fbg, and AT testing. Plasma samples stored 24 hours in primary tubes at 4°C are suitable for D-dimer testing.

Background: Widespread use of D-dimer in recent years has led to the development of a number of new fully automated quantitative D-dimer assays. Methods: We evaluated the analytical performance of the particle-enhanced immunoturbidimetric assay Innovance D-DIMER (Siemens Medical Solutions) on the Behring Coagulation System (BCS) analyzer. Results: Within-run coefficients of variation (CVs) for samples with low, borderline, slightly, and extremely increased D-dimer concentrations were 2.1%-5.5%, whereas between-run CVs for control samples with low and extremely increased D-dimer were 5.5%-