Molecular Analysis of Prothrombotic Gene Variants in Patients with Acute Ischemic Stroke and with Transient Ischemic Attack

The relevance of prothrombotic genetic variants in women who experienced pregnancy loss or embryo implantation failure: A retrospective analysis of 1922 cases

OBJECTIVE

The aim of our study was that to assess the allelic and genotype frequencies of nine prothrombotic gene variants in patients with a history of pregnancy loss and recurrent pregnancy loss (RPL). Women who underwent assisted reproductive technology (ART) with ongoing pregnancy and those with recurrent implantation failure (RIF) were also included.

METHODS

Nine prothrombotic gene variants were evaluated: factor V Leiden (FVL), factor V, H1299R variant (FVR2), factor II (FII) G20210A, methylene-tetrahydrofolate reductase (MTHFR) C677T and A1298C, beta-fibrinogen -455G>A, factor XIII (FXIII) V34L, human platelet antigen-1 (HPA-1) L33P variants, and plasminogen activator inhibitor-1 (PAI-1) 4G/5G. The following study groups were assessed: (1) women who experienced one (n = 334) or two (n = 264) episodes of pregnancy loss; (2) 468 women who experienced RPL; (3) 214 women who underwent ART followed by ongoing pregnancies; and (4) 282 women who experienced RIF after ART, that is, three or more consecutive implantation failures following high-quality embryo transfers to the uterus with an appropriate endometrium. As control group, 430 subjects from the general population were enrolled.

RESULTS

FVL, the -455G>A variant of beta-fibrinogen, and PAI-1 4G were associated with a higher risk of developing RPL compared with the general population. Furthermore, FVL, FVR2, FII G20210A and MTHFR C677T conferred a significantly higher risk of RIF in women who performed ART compared with the general population. No statistical differences between the general population and other study groups were observed.

CONCLUSIONS

Specific prothrombotic genetic variants are more frequently expressed in women with RPL and RIF, supporting their role in the development of polimicrothrombosis and impairing the invasion during embryo implantation.

Thrombophilia screening in the routine clinical care of children with arterial ischemic stroke

BACKGROUND

Current guidelines recommend thrombophilia evaluation in childhood arterial ischemic stroke, but the impact of screening on management is unknown. The objective of the current study is to report the incidence of thrombophilia identified as part of routine clinical care in the context of available literature reports, and to describe the impact of a diagnosis of thrombophilia on patient management.

METHODS

We conducted a single-institution retrospective chart review for all children with arterial ischemic stroke occurring between January 1, 2009 and January 1, 2021. We collected thrombophilia screening results, stroke etiology, and management. We also reviewed the literature of thrombophilia testing in childhood arterial ischemic stroke published prior to June 30, 2022. Meta-analysis methods were used to assess prevalence rates.

RESULTS

Among children with thrombophilia testing performed, 5% (six of 122 patients) were factor V Leiden heterozygous, 1% (one of 102 patients) were prothrombin gene mutation heterozygous, 1% (one of 122) had protein S deficiency, 20% (23/116 patients) had elevated lipoprotein(a), 3% (three of 110 patients) had elevated homocysteine levels, and 9% (10/112) had elevated antiphospholipid antibodies, only two of whom had persistently elevated levels. There was no change in stroke therapy due to these results. Literature review revealed a wide range of prevalence for most thrombophilia traits, with high cross-study heterogeneity in most cases.

CONCLUSIONS

The rates of thrombophilia in our cohort were consistent with that expected in the general population. The identification of thrombophilia did not alter stroke care. However, some of the results were actionable, prompting evaluation for lipid disorders and patient-specific counseling on cardiovascular risk and risk for venous thrombosis.

Association of methylenetetrahydrofolate reductase (MTHFR) rs1801133 (677C>T) gene polymorphism with ischemic stroke risk in different populations: An updated meta-analysis

Background: Recently, increasing evidence has implicated methylenetetrahydrofolate reductase (MTHFR) gene mutation as a risk factor for ischemic stroke (IS) in the general population. However, studies have been inconclusive and lack evidence on specific populations. We aim to determine whether the rs1801133 (NC_000001.11 (MTHFR):g. 677C>T (p.Ala222Val) variant, we termed as MTHFR rs1801133 (677 C>T), is linked to an increased risk of IS in different age groups and ancestry groups. Methods: The literature relevant to our study was found by searching the PubMed, Cochrane Library, Web of Science, EMBASE, and CNKI databases. A random effect model analysis was used to calculate the pooled odds ratio (OR) and 95% confidence interval (CI) to evaluate any possible association. We conducted a subgroup analysis based on the age and ancestry groups of the included populations. Results: As of March 2022, 1,925 citations had been identified in electronic databases, of which 96 studies involving 34,814 subjects met our eligibility criteria. A strong link was found between IS and the MTHFR gene rs1801133 (677C>T) polymorphism in all genetic models [dominant genetic model (OR = 1.47; 95%CI = 1.33-1.61; p < 0.001), recessive genetic model (OR = 1.52; 95%CI = 1.36-1.71; p < 0.001), heterozygous model (OR = 1.36; 95%CI = 1.24-1.48; p < 0.001), homozygous model (OR = 1.82; 95%CI = 1.58-2.11; p < 0.001), and T allelic genetic model (OR = 1.37; 95%CI = 1.27-1.48; p < 0.001)]. Further subgroup analyses indicated that the MTHFR rs1801133 (677C>T) variant may increase the risk of IS in Asian, Hispanic, or Latin population, middle-aged, and elderly populations (p < 0.001). Conclusion: Our results implied that mutation of the T allele of MTHFR rs1801133 (677C>T) could be a risk factor for IS. A significant association was found among Asian, Hispanic, or Latin population, middle-aged, and elderly people.

Myocardial Infarction Following COVID-19 Vaccine Administration: Post Hoc, Ergo Propter Hoc?

Vaccination against coronavirus disease 2019 (COVID-19) is the safest and most effective strategy for controlling the pandemic. However, some cases of acute cardiac events following vaccine administration have been reported, including myocarditis and myocardial infarction (MI). While post-vaccine myocarditis has been widely discussed, information about post-vaccine MI is scarce and heterogenous, often lacking in histopathological and pathophysiological details. We hereby present five cases (four men, mean age 64 years, range 50–76) of sudden death secondary to MI and tightly temporally related to COVID-19 vaccination. In each case, comprehensive macro- and microscopic pathological analyses were performed, including post-mortem cardiac magnetic resonance, to ascertain the cause of death. To investigate the pathophysiological determinants of MI, toxicological and tryptase analyses were performed, yielding negative results, while the absence of anti-platelet factor 4 antibodies ruled out vaccine-induced thrombotic thrombocytopenia. Finally, genetic testing disclosed that all subjects were carriers of at least one pro-thrombotic mutation. Although the presented cases do not allow us to establish any causative relation, they should foster further research to investigate the possible link between COVID-19 vaccination, pro-thrombotic genotypes, and acute cardiovascular events.

Multiple sclerosis and genetic polymorphisms in fibrinogen-mediated hemostatic pathways: a case-control study

INTRODUCTION

Blood coagulation constituents might exert immunomodulatory functions in the CNS and may trigger neuroinflammation and demyelination. We evaluated whether particular single-nucleotide polymorphisms (SNPs), thought to be involved in fibrinogen-mediated hemostatic pathways, are overrepresented in patients with MS compared with controls.

METHODS

The case-control study consisted of 119 MS patients recruited consecutively at our clinic, and 68 healthy controls. Afterwards, we created a cumulative genetic risk score (CGRS) which included the 5 selected hemostatic risk alleles (Beta-Fibrinogen 455G/A, Glycoprotein IIIa P1A2, Factor V Leiden, Factor V H2R, and Prothrombin 20210G/A). Multivariate ordinal logistic regression and multivariate multinomial logistic regression were applied to evaluate the effect of CGRS on MS susceptibility.

RESULTS

The FGB 455 G/A and Factor V H1299R variants might be associated with MS status, in the recessive and dominant model, respectively. A cumulative association of the five SNPs investigated with the disease was observed.

DISCUSSION

We found that MS patients carried more pro-hemostatic variants than healthy controls. An increasing number of unfavorable alleles might increase the likelihood of being in the MS group, in the cumulative analysis. Our findings encourage to evaluating these variants in a larger population-based cohort.