Maternal cerebral venous thrombosis, uncommon but serious disorder, pathologic predictors and contribution of prothrombotic abnormalities

The risk profiles of pregnancy-related cerebral venous thrombosis: a retrospective study in a comprehensive hospital

OBJECTIVES

To investigate the risk factors and underlying causes of pregnancy-related cerebral venous thrombosis (PCVT).

METHODS

A retrospective cohort of 16 patients diagnosed with CVT during pregnancy and postpartum (within six weeks after delivery) in a comprehensive hospital in China between 2009 and 2022 were carefully reviewed, focusing on demographic, clinical, and etiological characteristics, especially underlying causes. We matched 16 PCVT patients with 64 pregnant and puerperal women without PCVT to explore risk factors and clinical susceptibility to PCVT.

RESULTS

PCVT occurred commonly during the first trimester (43.75%) and the puerperium (37.5%). The frequency of anemia, thrombocytosis and thrombocytopenia during pregnancy, dehydration, and pre-pregnancy anemia was significantly higher in women with PCVT than in those without PCVT (P < 0.05). Among the 16 patients, five were diagnosed with antiphospholipid syndrome and one was diagnosed with systemic lupus erythematosus. Three patients had distinct protein S deficiency and one had protein C deficiency. Whole Exome Sequencing (WES) was performed for five patients and revealed likely pathogenic mutations associated with CVT, including heterozygous PROC c.1218G > A (p. Met406Ile), heterozygous PROS1 c.301C > T (p. Arg101Cys), composite heterozygous mutation in the F8 gene (c.144-1259C > T; c.6724G > A (p. Val2242Met)) and homozygous MTHFR c.677C > T (p. Ala222Val).

CONCLUSIONS

The occurrence of anemia, thrombocytopenia and thrombocytosis during pregnancy, dehydration and pre-pregnancy anemia suggested a greater susceptibility to PCVT. For confirmed PCVT patients, autoimmune diseases, hereditary thrombophilia, and hematological disorders were common causes. Screening for potential etiologies should be paid more attention, as it has implications for treatment and long-term management.

Predictors of Mortality and Functional Outcome in Pregnancy and Puerperium-Related Cerebral Venous Thrombosis

INTRODUCTION

Cerebral venous thrombosis (CVT) associated with pregnancy and puerperium has long been recognized, with poor information in terms of functional outcomes. Our objective was to analyze risk factors, clinical, imaging, and laboratory variables to predict functional outcome and death in this population.

METHODS

CVT registries from three referral centers from Pakistan, Turkey, and Mexico, recruiting prospective cases, were combined for CVT associated with pregnancy or puerperium. Datasets and variables were standardized. Demographic characteristics, presentation, risk factors, and functional outcomes in pregnancy/puerperium-related CVT were analyzed. Binary logistic regression was used to assess predictors of outcome. The main outcome was modified Rankin score >2 at 30 days and mortality at 30 days.

RESULTS

Five hundred fifty-three cases (median age 28 years [IQR 23-34]) of CVT associated with pregnancy and puerperium were included; 439 cases (79.4%) happened in the puerperium and 20.6% during pregnancy (53.5% occurred during the first trimester). Anemia (36.7%) and dehydration (22.9%) were the commonest obstetric risk factors identified. Predictors of poor outcome (mRS >2) were encephalopathy (OR 12.8, p < 0.001), cases from Mexican origin (OR 3.1, p = 0.004), fever/puerperal infection (OR 2.7, p = 0.02), and anemia (OR 2.2, p = 0.01). Cases from Mexican origin (OR 12.0, p = 0.003) and Encephalopathy (OR 7.7, p < 0.001), presented with the highest mortality association in the final adjusted model.

DISCUSSION/CONCLUSION

In CVT associated with pregnancy and puerperium, encephalopathy, fever/puerperal infection, and anemia are associated with bad functional outcomes, meanwhile encephalopathy and cases from Mexican origin with higher mortality in the acute (30-days) of CVT onset. Anemia and infection are potential reversible predictors of poor outcome that clinicians should be aware of in order to prevent poor outcomes in these patients.

Thrombophilia and venous thromboembolism in pregnancy: a meta-analysis of genetic risk

Three common polymorphic variants, namely Factor V Leiden (FVL), Prothrombin G20210A (PT G20210A) and Methylenetetrahydrofolate Reductase (MTHFR) C677T are candidate genes for venous thromboembolism (VTE) in pregnancy. We performed a literature review and meta-analysis of pertinent genetic association studies (GAS) in pregnancy, to quantify the genetic risk of VTE in pregnancy. We used the model-free approach of generalized odds ratio (ORG) to estimate gene-to-disease association and explored the mode of inheritance using the degree of dominance h index. Twelve case-control GAS studies provided the full genotype distributions for at least one candidate gene to assess the genetic risk. FVL was associated with a significant risk of VTE in pregnancy (ORG 7.28; 95% confidence interval 5.53-9.58) and a dominant mode of inheritance (h=0.76), that is the effect of heterozygous carriers will lie close to the homozygous mutant genotype. PT G20210A mutation was also associated with a significant VTE risk (ORG 5.43; 95% CI 3.66-8.03) and had an over-dominant mode of inheritance (h=1.5), suggesting that the effect of heterozygous carriers may exceed that of homozygous mutant. MTHFR C677T had no association with VTE risk in pregnancy (ORG 1.24; 95% CI 0.88-1.73). Our analysis provided robust data on VTE in pregnancy, relative to FVL and PT G20210A status and suggested that the genetic effects of heterozygous over homozygous carriers do not justify stratification of heterozygous as "lower risk" over homozygous mutants. On clinical grounds this may impact decisions to preferentially exclude heterozygous from anticoagulation prophylaxis.