Epidural/spinal anesthesia during delivery in women with factor XI deficiency, a single center experience

Factor XI deficiency: phenotypic age-related considerations and clinical approach towards bleeding risk assessment

ABSTRACT

Factor XI (FXI) deficiency is a rare bleeding disorder that presents complex challenges in patient assessment and bleeding risk management. Despite generally causing mild to moderate bleeding symptoms, clinical manifestations can vary, and bleeding tendency does not always correlate with FXI plasma levels or genotype. Our manuscript delves into the age-related nuances of FXI deficiency across an individual's lifespan. We emphasize issues faced by specific groups, including neonates and females of reproductive age experiencing abnormal uterine bleeding and postpartum hemorrhage. Older patients present unique challenges and concerns related to the management of bleeding as well as thrombotic complications. The current assortment of diagnostic laboratory assays shows limited success in predicting bleeding risk in the perisurgical setting of patients with FXI deficiency. This review explores the intricate interplay between individual bleeding profiles, surgical sites, and FXI activity levels. We also evaluate the accuracy of existing laboratory assays in predicting bleeding and discuss the potential role of investigational global assays in perioperative assessment. Furthermore, we outline our suggested diagnostic approach to refine treatment strategies and decision making. Available treatment options are presented, including antifibrinolytics, replacement products, and recombinant activated FVII. Finally, we discuss promising nonreplacement therapies for the treatment of rare bleeding disorders that can potentially address the challenges faced when managing FXI deficiency-related bleeding complications.

Evaluation of thrombin generation assay in factor XI deficiency

INTRODUCTION

Factor XI (FXI) deficiency is characterized by a lack of correlation between FXI plasma levels and the occurrence of hemorrhagic events. The main objective of our study was to determine whether thrombin generation assay (TGA) could be used to assess the hemorrhagic phenotype of patients with FXI deficiency.

MATERIAL AND METHODS

All patients had confirmed laboratory measurement of FXI < 50% in two plasma samples. Relevant bleeding history was evaluated by a senior physician. TGA was performed with Calibrated Automated Thrombography, in platelet poor plasma, from patients and healthy controls. The assay was performed with PPP low reagent (1 pM of human tissue factor).

RESULTS

Seventy-six patients with FXI deficiency were included between 2011 and 2020. Among them, eight patients had severe deficiency (FXI < 15%). Mean age was 34 years [range: 9-77]. Endogenous thrombin potential (ETP) was significantly lower in patients with FXI deficiency and bleeding (573 nM·min [225-1214]) or no bleeding (732 nM·min [222-1435]), compared to healthy controls (1184 nM·min [933-1518]). No difference was observed for ETP and peak between patients with FXI deficiency and bleeding and patients with FXI deficiency and no bleeding. No difference was observed for ETP (923 nM·min [377-1497] vs 1063 nM·min [252-2529]), peak (82 nM [28-154] vs 131 nM [20-330]) or velocity (13.7 nM/min [3.6-29.6] vs 26.5 nM/min [2.5-90]) in women with (n = 4) and without history (n = 17) of post-partum bleeding. No difference of thrombin generation was observed in pregnant women with FXI deficiency (ETP: 1395 nM·min [351-2529]; peak: 154 nM [26-330]; velocity: 29.6 nM/min [4.1-90.0]), compared to healthy controls and a control group of healthy pregnant women.

CONCLUSION

In conclusion, under our experimental condition, a non-significant decrease of thrombin generation was observed in plasma samples of patients with FXI deficiency and bleeding. Our results suggest an increase of coagulation parameters during pregnancy in women with FXI deficiency. A larger sample size or other experimental conditions are required to evaluate the use of TGA in FXI deficiency.