Fibrinogen concentrate for bleeding in patients with congenital fibrinogen deficiency: Observational study of efficacy and safety for prophylaxis and treatment

A case of anaphylactic shock to human fibrinogen infusion during cardiac surgery

Human fibrinogen (FIB) has been clinically proven to be considerably effective for the treatment of postoperative bleeding, with reported cases of allergic reactions to human FIB being rare. Here, we report a case of an anaphylactic shock in 27-year-old patients with rheumatic heart valve disease who received a human FIB infusion during mitral valve replacement, aortic valve replacement, and tricuspid valve-shaping surgery. The patients showed generalised profuse sweating, a barely noticeable skin rash, faint pulse, systolic pressure < 50 mmHg, and a heart rate of 71 beats/min. We share insights from a case of severe allergy to human FIB infusion during cardiac surgery, through which we have gained experience in the processes of diagnosing and treating. This report aims to provide a preliminary summary of the characteristics of this case to serve as a reference for fellow clinicians.

Long-Term Safety Analysis of a Fibrinogen Concentrate (RiaSTAP®/Haemocomplettan® P)

Fibrinogen concentrate treatment is recommended for acute bleeding episodes in adult and pediatric patients with congenital and acquired fibrinogen deficiency. Previous studies have reported a low risk of thromboembolic events (TEEs) with fibrinogen concentrate use; however, the post-treatment TEE risk remains a concern. A retrospective evaluation of RiaSTAP®/Haemocomplettan® P (CSL Behring, Marburg, Germany) post-marketing data was performed (January 1986-June 2022), complemented by a literature review of published studies. Approximately 7.45 million grams of fibrinogen concentrate was administered during the review period. Adverse drug reactions (ADRs) were reported in 337 patients, and 81 (24.0%) of these patients experienced possible TEEs, including 14/81 (17.3%) who experienced fatal outcomes. Risk factors and the administration of other coagulation products existed in most cases, providing alternative explanations. The literature review identified 52 high-ranking studies with fibrinogen concentrate across various clinical areas, including 26 randomized controlled trials. Overall, a higher number of comparative studies showed lower rates of ADRs and/or TEEs in the fibrinogen group versus the comparison group(s) compared with those that reported higher rates or no differences between groups. Post-marketing data and clinical studies demonstrate a low rate of ADRs, including TEEs, with fibrinogen concentrate treatment. These findings suggest a favorable safety profile of fibrinogen concentrate, placing it among the first-line treatments effective for managing intraoperative hemostatic bleeding.

One Hundred Years of Congenital Fibrinogen Disorders

Congenital fibrinogen disorders encompass a broad range of fibrinogen defects characterized by a wide molecular and clinical spectrum. From the first clinical description of afibrinogenemia in 1920, many major achievements have contributed to a better understanding of these complex disorders. The finding of causative mutations in all three fibrinogen genes has contributed to reveal the molecular mechanisms involved in biosynthesis of the fibrinogen molecule and to clarify the basic processes of fibrin polymerization and fibrinolysis. The compilation of abundant cases with detailed genetic, biological, and clinical features has enabled the classification of congenital fibrinogen disorders into several types and subtypes. Thus, the recent classification of congenital fibrinogen disorder is based not only on the clottable and antigenic fibrinogen levels but also on the patient's clinical phenotype and genotype. Fibrinogen supplementation is the cornerstone of bleeding management in fibrinogen disorders. Since the discovery of blood fractionation, the method of production of fibrinogen concentrate has been progressively modified to significantly improve purity and safety. Nevertheless, the availability of such products is still limited to a few countries and the optimal threshold of fibrinogen to target is still not established. In this review, we describe the major advances that have characterized 100 years of congenital fibrinogen disorders, focusing on afibrinogenemia and dysfibrinogenemia.

Fibrinogen concentrate and maternal outcomes in severe postpartum hemorrhage: A population-based cohort study with a propensity score-matched analysis

STUDY OBJECTIVE

Fibrinogen concentrate is used to treat severe postpartum hemorrhage despite limited evidence of its effectiveness in obstetric settings. We aimed to explore the association between its administration and maternal outcomes in women with severe postpartum hemorrhage.

DESIGN, SETTING AND PATIENTS

This secondary analysis of the EPIMOMS prospective population-based study, exploring severe maternal morbidity, as defined by national expert consensus (2012-2013, 182,309 deliveries, France), included all women with severe postpartum hemorrhage and transfused with red blood cells during active bleeding.

MEASUREMENTS

The primary endpoint was maternal near-miss or death, and the secondary endpoint the total number of red blood cells units transfused.

INTERVENTIONS

We studied fibrinogen concentrate administration as a binary variable and then by the timing of its administration. We used multivariable analysis and propensity score matching to account for potential indication bias.

MAIN RESULTS

Among the 730 women with severe postpartum hemorrhage and transfused, 313 (42.9%) received fibrinogen concentrate, and 142 (19.5%) met near-miss criteria or died. The risk of near-miss or death was not significantly lower among the women treated with fibrinogen concentrate than among those not treated, in either the multivariable analysis (adjusted RR = 1.03; 95% CI, 0.72-1.49; P = 0.855) or the propensity score analysis (RR = 0.85; 95% CI, 0.55-1.32; P = 0.477). Among women treated with fibrinogen concentrate, administration more than three hours after red blood cell transfusion started was associated with a higher risk of near-miss or death than administration before or within 30 min after the transfusion began (adjusted RR = 2.07; 95% CI, 1.10-3.89; P = 0.024). Results were similar for the secondary endpoint.

CONCLUSIONS

The use of fibrinogen concentrate in severe postpartum hemorrhage needing red blood cell transfusion during active bleeding is not associated with improved maternal outcomes.

Impact of fibrinogen infusion on thrombin generation and fibrin clot structure in patients with inherited afibrinogenemia

INTRODUCTION

Inherited afibrinogenemia is a very rare disease characterized by complete absence of fibrinogen in the circulation and an increased risk in both thrombosis and bleeding. Infusion of fibrinogen concentrate (FC) is the main approach for prevention and management of bleeding; however, it has been reported to carry a thrombotic risk.

METHODS

We investigated the impact of a standard dose (40-100 mg/kg) of FC infusion on the thrombin generation (TG) parameters and the fibrin clot structure formed in plasma samples of patients with afibrinogenemia. Blood samples were collected from 20 patients before (T0) and 1 hour after infusion of FC (T1). TG was studied with Calibrated Automated Thrombography. Fibrin clot structure was assessed with turbidimetry and scanning electron microscopy (SEM).

RESULTS

FC infusions (mean Clauss fibrinogen plasma level 1.21 g/L at T1) led to a statistically significant increase in endogenous thrombin potentials (ETP) (p<0.0001) and thrombin peaks (p=0.02). Nevertheless, when compared to healthy controls, patients' T1 lag times were longer (p=0.002), ETP values were lower (p=0.0003), and thrombin peaks were lower (p<00001). All fibrin polymerization parameters (turbidimetry) obtained at T1 were comparable to those of patients with inherited hypofibrinogenemia matched for fibrinogen plasma levels.

CONCLUSIONS

In summary, fibrinogen infusion with a standard dose of FC increased but did not correct TG and led to formation of fibrin clots similar to those of patients with hypofibrinogenemia. All in all, our results do not support to biological evidence of hypercoagulability induced by FC in patients with afibrinogenemia.

Disorders of Fibrinogen and Fibrinolysis

Fibrinogen plays a fundamental role in coagulation through its support for platelet aggregation and its conversion to fibrin. Fibrin stabilizes clots and serves as a scaffold and immune effector before being broken down by the fibrinolytic system. Given its importance, abnormalities in fibrin(ogen) and fibrinolysis result in a variety of disorders with hemorrhagic and thrombotic manifestations. This review summarizes (i) the basic elements of fibrin(ogen) and its role in coagulation and the fibrinolytic system; (ii) the laboratory evaluation for fibrin(ogen) disorders, including the use of global fibrinolysis assays; and (iii) the management of congenital and acquired disorders of fibrinogen and fibrinolysis.

Cell Attachment Capacity and Compounds of Fibrin Membranes Isolated from Fresh Frozen Plasma and Cryoprecipitate

Fibrin membranes are widely used in regenerative medicine because they are biocompatible, biodegradable, contain growth factors, and support cell attachment. Most commonly they are produced from serum, but they can also be isolated from activated plasma. To increase the fibrinogen concentration of plasma, cryoprecipitate isolation is a possible solution. In this work, cryoprecipitate was prepared from fresh frozen plasma, isolated by plasmapheresis. The concentration of cellular elements, fibrinogen, total protein, and immunoglobulins among others was measured in different concentrations of cryoprecipitates. After activation with Ca-gluconate, fibrin membranes were produced in different thicknesses, and human mesenchymal stem cells were seeded onto the membranes. They were visualized by live-dead staining and their viability was determined by XTT. The platelet-derived growth factor AB content was quantified by ELISA. Our results showed that fibrinogen and platelet concentration can be multiplied in plasma by cryoprecipitate isolation, which affects the thickness and slightly the growth factor content of the membranes. According to live-dead staining, the thickness of the membranes does not influence cell attachment, and XTT measurement did not reveal a significant difference in cell attachment capacity either; however, a growing trend could be observed in the case of some membranes.