Incidence, clinical features, and risk factors of hemocoagulase-induced hypofibrinogenemia: A retrospective real-world study.

The objective of this study was to explore the real-world incidence, severity, clinical features, and potential risk factors associated with hypofibrinogenemia induced by hemocoagulase. Based on Chinese Hospital Pharmacovigilance System, a retrospective case-control study was conducted, enrolling hospitalized patients who received hemocoagulase for the treatment or prevention of hemorrhage in Weifang People's Hospital in China from January 2021 to May 2022. Univariate and multivariate logistic regression was performed to analyze the potential risk factors. Out of 10,397 hospitalized patients who received hemocoagulase, 341 patients showed positive triggers, with 235 patients ultimately conformed as hemocoagulase-associated hypofibrinogenemia. The system positive alarm rate was 68.91%, and the overall incidence of hemocoagulase-induced hypofibrinogenemia was 2.26%, predominantly characterized by mild to moderate severity levels. The incidence varied among the 4 types of hemocoagulase, with the highest incidence observed in hemocoagulase Agkistrodon Halys Pallas at 4.59%. The incidence of hemocoagulase from Deinagkistrodon acutus, Bothrops Atrox and Adder were 0.97%, 0.44% and 0.12%, respectively. Multivariate logistic regression analysis revealed that age (odds ratios [OR] = 177.328, P < .001), source of snake venom (OR = 5.641, P < .05), albumin (OR = 2.487, P < .001), and cumulative dosage (OR = 1.106, P < .001) were independent risk factors. Increased risk of hemocoagulase-related hypofibrinogenemia may be associated with children, elderly patients, low albumin levels, high cumulative doses and hemocoagulase from Agkistrodon Halys Pallas. Early recognition and close drug monitoring for these high-risk patients are vital in clinical practice.

Clinical observation of hypofibrinogenemia induced by the treatment of tocilizumab in rheumatic diseases and exploration of risk factor for hypofibrinogenemia.

OBJECTIVE: The objective of this study was to analyze the changes in plasma fibrinogen (FIB) levels during tocilizumab (TCZ) treatment in patients with rheumatic diseases, to clarify the incidence of hypofibrinogenemia and its possible risk factors, and to establish a nomogram model for predicting the probability of hypofibrinogenemia in rheumatoid arthritis (RA) patients treated with TCZ. METHODS: Clinical data of patients treated with TCZ at the Department of Rheumatology and Immunology, the First Affiliated Hospital of Xi'an Jiaotong University from January 2014 to October 2021 were retrospectively analyzed to observe the incidence of hypofibrinogenemia in several rheumatic diseases at different time points. The risk factor of hypofibrinogenemia in RA patients treated with TCZ was determined by using Cox regression analysis. Based on the results of Cox regression analysis, a nomogram for predicting the probability of hypofibrinogenemia in rheumatoid arthritis (RA) patients treated with TCZ was established and validated through RStudio software. RESULTS: A total of 83 TCZ-treated patients were enrolled in this study, and 32 (38.55%) patients developed hypofibrinogenemia during TCZ treatment. There were 8 males and 24 females in the FIB-reduced group, with an average age of 44.88 ± 18.39 years. Hypofibrinogenemia was most common in TCZ-treated patients with takayasu arteritis (TA) and RA. Hypofibrinogenemia typically occured within 3 months after TCZ treatment. In RA patients treated with TCZ, platelet distribution width, parathyroid hormone, bone mineral density, tender joint count, and swollen joint count were independent risk factors for the occurrence of hypofibrinogenemia. The nomogram based on the above risk factors could effectively predict the probability of hypofibrinogenemia in RA patients receiving TCZ. CONCLUSION: Although bleeding symptoms were not observed in this study, the incidence of hypofibrinogenemia remained high after TCZ treatment, usually occurring within 3 months of treatment. Therefore, it is necessary to monitor FIB levels during TCZ treatment. In addition, clinicians can use the nomogram model developed from this study to predict the incidence of hypofibrinogenemia after TCZ treatment in RA patients. Key Points • Hypofibrinogenemia often occurs during TCZ treatment for rheumatic diseases. • PDW, PTH, BMD, tender joint count, and swollen joint count are risk factors for the occurrence of hypofibrinogenemia. • It is necessary to monitor FIB levels during TCZ treatment to avoid bleeding tendency.

Tigecycline-associated hypofibrinogenemia: A single center, retrospective, controlled study.

BACKGROUND: Tigecycline-associated hypofibrinogenemia has been reported as an important adverse effect in recent years, but controlled studies minimizing confounding factors are needed. The objective of our study was to assess changes in fibrinogen levels in patients for hospitalization, comparing two antibiotic episodes (tigecycline and other) within the same patients. METHODS: The retrospective, self-controlled case series study was conducted at our University Hospitals. The study compared the change in fibrinogen levels during the patient's hospitalization for tigecycline (TigePer) and another antibiotic period (OtherPer). In addition, bleeding events, bleeding risk (determined by the IMPROVE bleeding risk score), as well as 15- and 30-day mortality rates between TigePer and OtherPer were compared. RESULTS: The study enrolled 50 patients with 100 episodes of antibiotic treatment. The median age (interquartile range) of the patients was 68.5 (21.5) years, and 38 % were female. As compared to OtherPer, TigePer had a statistically significant reduction in fibrinogen levels (p < 0.001), with a hypofibrinogenemia rate of 40 % in TigePer as compared to 2 % in OtherPer (p < 0.001). TigePer demonstrated a significantly higher 15-day mortality rate (p = 0.006). No significant differences were observed between the two periods in terms of bleeding risk, rate of bleeding events, and 30-day mortality rate (p > 0.05). CONCLUSION: Hypofibrinogenemia and other coagulopathies, without associated bleeding events, are more frequently observed in patients receiving tigecycline. Therefore, it is crucial for clinicians to monitor fibrinogen levels during tigecycline use.

Rare bleeding disorders: Advances in management.

Inherited factor coagulation deficiencies and vascular bleeding disorders, associated with bleeding of various severity, are often classified as rare bleeding disorders (RBDs). These include inherited fibrinogen disorders, inherited platelet function disorders (IPFD) and hereditary haemorrhagic telangiectasia (HHT). In the last decades, there have been large increases in knowledge on the epidemiology, genetics, physiopathology, clinical features, and diagnosis of RBDs, but improvements in management have been more limited and remain challenging. The treatment mainstay of RBDs is based only on replacement of a few available coagulation factor concentrates or cryoprecipitates. There is growing interest in therapeutic agents that enhance coagulation or inhibiting anticoagulant pathways in RBDs. In severe IPFD, the optimal platelet transfusion strategy is not yet established. Moreover, data is scarce on the effectiveness and safety of desmopressin and/or antifibrinolytic drugs often used for milder IPFD treatment. The best fibrinogen replacement strategy (prophylaxis vs. on demand) in afibrinogenemia is still debated. Similarly, the optimal trough fibrinogen target level for treatment of acute bleeding, and the role of fibrinogen replacement during pregnancy in mild hypofibrinogenemia and dysfibrinogenemia, have not been properly evaluated. The therapeutic arsenal in HHT includes antifibrinolytics and a series of antiangiogenic agents whose potential efficacy has been tested in small studies or are under investigation for treatment of bleeding. However, there is need to address several issues, including the optimal dosing strategies, the potential emergent toxicity of longer-term use, and the impact of systemic antiangiogenic treatment on visceral arteriovenous malformations.

Effect of low fibrinogen level on in-hospital mortality and 6-month functional outcome of TBI patients, a single center experience.

In patients affected by traumatic brain injury (TBI), hypofibrinogenemia within the initial hours of trauma can be expected due to vascular and inflammatory changes. In this study, we aimed to evaluate the effect of hypofibrinogenemia on the in-hospital mortality and 6-month functional outcomes of TBI patients, admitted to Rajaee Hospital, a referral trauma center in Shiraz, Iran. This study included all TBI patients admitted to our center who had no prior history of coagulopathy or any systemic disease, were alive on arrival, and had not received any blood product before admission. On admission, hospitalization, imaging, and 6-month follow-up information of included patients were extracted from the TBI registry database. The baseline characteristics of patients with fibrinogen levels of less than 150 mg/dL were compared with the cases with higher levels. To assess the effect of low fibrinogen levels on in-hospital mortality, a uni- and multivariate was conducted between those who died in hospital and survivors. Based on the 6-month GOSE score of patients, those with GOSE < 4 (unfavorable outcome) were compared with those with a favorable outcome. A total of 3049 patients (84.3% male, 15.7% female), with a mean age of 39.25 ± 18.87, met the eligibility criteria of this study. 494 patients had fibrinogen levels < 150 mg/dl, who were mostly younger and had lower average GCS scores in comparison to cases with higher fibrinogen levels. By comparison of the patients who died during hospitalization and survivors, it was shown that fibrinogen < 150 mg/dl is among the prognostic factors for in-hospital mortality (OR:1.75, CI: 1.32:2.34, P-value < 0.001), while the comparison between patients with the favorable and unfavorable functional outcome at 6-month follow-up, was not in favor of prognostic effect of low fibrinogen level (OR: 0.80, CI: 0.58: 1.11, P-value: 0.19). Hypofibrinogenemia is associated with in-hospital mortality of TBI patients, along with known factors such as higher age and lower initial GCS score. However, it is not among the prognostic factors of midterm functional outcome.

A novel mutation in the FGG gene causes hypofibrinogenemia in a Chinese family.

Congenital fibrinogen disorders are a group of coagulation deficiencies caused by fibrinogen defects and are divided into four types, including afibrinogenemia, hypofibrinogenemia, dysfibrinogenemia, and hypodysfibrinogenemia. In this study, we collected a family with hypofibrinogenemia, and genetics analysis identify a novel pathogenic variants (c.668G > C, p.Arg223Thr) in the FGG gene. And electron microscope observation revealed significant changes in the ultrastructure of fibrin of the proband. Our research expands the phenotypic and genetic spectrum associated with the FGG gene, which would facilitate in genetic counselling and prenatal genetic diagnosis.

Envenomation by Eyelash Viper Bothriechis schlegelii (Berthold, 1846) in Southwestern Colombia.

INTRODUCTION: Bothriechis schlegelii is a Crotaline viperid species of Central America and Northern South America. The characteristics of its envenomation have not been well established. We present clinical characteristics of human cases evaluated and treated in a hospital in southwestern Colombia. METHODS: We evaluated data from patients who suffered Bothriechis schlegelii envenomation and were seen at Fundación Valle del Lili Hospital, Cali, Colombia between 2011 and 2022. RESULTS: Eight patients were included, with a median age of 24 years. Snakebites occurred in rural areas. Six (75%) patients were bitten on the upper extremities in relation to the arboreal habits of this animal. The most common symptoms were pain and edema (N = 8, 100%), ecchymoses (N = 2, 25%), and paresthesia (N = 2, 25%). The most common systemic findings were hypofibrinogenemia (N = 8, 100%) and prolonged prothrombin time in five patients (N = 5, 62.5%). All were treated with polyvalent antivenom for Colombian snakes, with a good response and outcome. CONCLUSIONS: Most bite sites from B. schlegelii were on the upper limbs. All patients had both local manifestations, including edema, pain, and systemic effects with hypofibrinogenemia, but none had systemic bleeding. Every patient received antivenom and had favorable outcomes.

Acquired factor V and factor X Deficiency coexisting with acquired dysfibrinogenaemia in a patient with light chain myeloma.

An elderly woman with light chain myeloma presented with prolonged epistaxis and extensive cutaneous haematomas: her kappa/lambda ratio was high at 395, her coagulation screen, thrombin and reptilase times were abnormal, her FV and FX were in the low range in the absence of specific inhibitors, her Clauss fibrinogen was low at 0.95 g/l but antigenic FNG was 1.58 g/l. The patient denied treatment and died of progressive renal failure. We wish to describe the unusual association of FX and FV deficiency co-existing with an acquired dysfibrinogenaemia.

Diagnostic value of clot formation parameters determined by rotational thromboelastometry in 63 patients with congenital dysfibrinogenemia.

Rotational thromboelastometry (ROTEM) is a global hemostasis assay. The diagnosis added value of ROTEM in congenital dysfibrinogenemia remains to be established. The aim of this study was to analyze clot formation by ROTEM in a cohort of dysfibrinogenemic patients and to establish correlations with genotype, clinical features, and coagulation parameters. The study included genetically confirmed congenital dysfibrinogenemia cases (n = 63) and healthy controls ( n  = 50). EXTEM, INTEM, FIBTEM tests were used to measure ROTEM parameters, that is, clotting time (CT), clot formation time (CFT), maximal clot firmness (MCF) and amplitude 10 min after CT (A10). The ISTH bleeding assessment tool was used to determine bleeding episodes. CT (INTEM) was statistically significantly shorter in congenital dysfibrinogenemia patients compared to controls while CFT (EXTEM) was prolonged. Patients's MCF in EXTEM, INTEM, and FIBTEM were similar to controls while A10 (FIBTEM) was statistically significantly lower. Fibrinogen activity was positively correlated with fibrinogen antigen, A10 and MCF in all three assays. Bleeding phenotypes were observed in 23 (36.5%) patients. Only CFT in EXTEM and CT in INTEM were statistically different in patients with bleeding phenotype versus controls. Carriers of the FGA mutation p.Arg35His had a CT (EXTEM) slightly prolonged and a reduced A10 (FIBTEM) compared to controls. Some ROTEM parameters were able to distinguish congenital dysfibrinogenemia patients from controls, and patients with a bleeding phenotype. Prolonged CFT in EXTEM were associated with congenital dysfibrinogenemia and bleeding phenotype. Bleeding episodes in most patients were generally mild and prevalence of thrombosis was very low.

Congenital fibrinogen disorders: a retrospective clinical and genetic analysis of the Prospective Rare Bleeding Disorders Database.

ABSTRACT: Congenital fibrinogen deficiency (CFD) is a rare bleeding disorder caused by mutations in FGA, FGB, and FGG. We sought to comprehensively characterize patients with CFD using PRO-RBDD (Prospective Rare Bleeding Disorders Database). Clinical phenotypes, laboratory, and genetic features were investigated using retrospective data from the PRO-RBDD. Patients were classified from asymptomatic to grade 3 based on their bleeding severity. In addition, FGA, FGB, and FGG were sequenced to find causative variants. A total of 166 CFD cases from 16 countries were included, of whom 123 (30 afibrinogenemia, 33 hypofibrinogenemia, 55 dysfibrinogenemia, and 5 hypodysfibrinogenemia) were well characterized. Considering the previously established factor activity and antigen level thresholds, bleeding severity was correctly identified in 58% of the cases. The rates of thrombotic events among afibrinogenemic and hypofibrinogenemic patients were relatively similar (11% and 10%, respectively) and surprisingly higher than in dysfibrinogenemic cases. The rate of spontaneous abortions among 68 pregnancies was 31%, including 86% in dysfibrinogenemic women and 14% with hypofibrinogenemia. Eighty-six patients received treatment (69 on-demand and/or 17 on prophylaxis), with fibrinogen concentrates being the most frequently used product. Genetic analysis was available for 91 cases and 41 distinct variants were identified. Hotspot variants (FGG, p.Arg301Cys/His and FGA, p.Arg35Cys/His) were present in 51% of dysfibrinogenemia. Obstetric complications were commonly observed in dysfibrinogenemia. This large multicenter study provided a comprehensive insight into the clinical, laboratory, and genetic history of patients with CFDs. We conclude that bleeding severity grades were in agreement with the established factor activity threshold in nearly half of the cases with quantitative defects.

A novel missense mutation (FGG c.1168G > T) in the gamma chain of fibrinogen causing congenital hypodysfibrinogenemia with bleeding phenotype.

BACKGROUND: Fibrinogen plays pivotal roles in multiple biological processes. Genetic mutation of the fibrinogen coding genes can result in congenital fibrinogen disorders (CFDs). We identified a novel heterozygous missense mutation, FGG c.1168G > T (NCBI NM_000509.6), and conducted expression studies and functional analyses to explore the influence on fibrinogen synthesis, secretion, and polymerization. METHODS: Coagulation tests were performed on the patients to detect the fibrinogen concentration. Whole-exome sequencing (WES) and Sanger sequencing were employed to detect the novel mutation. Recombinant fibrinogen-producing Chinese hamster ovary (CHO) cell lines were built to examine the recombinant fibrinogen synthesis and secretion by western blotting and enzyme-linked immunosorbent assay (ELISA). The functional analysis of fibrinogen was performed by thrombin-catalyzed fibrin polymerization assay. In silico molecular analyses were carried out to elucidate the potential molecular mechanisms. RESULTS: The clinical manifestations, medical history, and laboratory tests indicated the diagnosis of hypodysfibrinogenemia with bleeding phenotype in two patients. The WES and Sanger sequencing revealed that they shared the same heterozygous missense mutation, FGG c.1168G > T. In the expression studies and functional analysis, the missense mutation impaired the recombinant fibrinogen's synthesis, secretion, and polymerization. Furthermore, the in silico analyses indicated novel mutation led to the hydrogen bond substitution. CONCLUSION: The study highlighted that the novel heterozygous missense mutation, FGG c.1168G > T, would change the protein secondary structure, impair the "A: a" interaction, and consequently deteriorate the fibrinogen synthesis, secretion, and polymerization.

Congenital fibrinogen disorders.

Congenital fibrinogen disorders are rare pathologies of the haemostasis, comprising afibrinogenaemia, hypofibrinogenaemia, dysfibrinogenaemia and hypodysfibrinogenaemia. Phenotypic manifestations are variable, patients may be asymptomatic or suffer from bleeding or thrombosis. Most of congenital fibrinogen disorders are coincidentally discovered. Fibrinogen concentrate is used to treat bleeding, whereas low-molecular weight heparin is most often administered for the treatment of thrombotic complications. The aim of this review is to provide an update of the knowledge of congenital fibrinogen disorders for Danish physicians.

The nature and timing of coagulation dysfunction in a cohort of trauma patients in the Australian pre-hospital setting.

BACKGROUND: Acute Traumatic Coagulopathy (ATC) is a complex pathological process that is associated with patient mortality and increased blood transfusion requirements. It is evident on hospital arrival, but there is a paucity of information about the nature of ATC and the characteristics of patients that develop ATC in the pre-hospital setting. The objective of this study was to describe the nature and timing of coagulation dysfunction in a cohort of injured patients and to report on patient and pre-hospital factors associated with the development of ATC in the field. METHODS: This was a prospective observational study of a convenience sample of trauma patients. Patients had blood taken during the pre-hospital phase of care and evaluated for derangements in Conventional Coagulation Assays (CCA) and Rotational Thromboelastometry (ROTEM). Associations between coagulation derangement and pre-hospital factors and patient outcomes were evaluated. RESULTS: A total of 216 patients who had either a complete CCA or ROTEM were included in the analysis. One hundred and eighty (83 %) of patients were male, with a median injury severity score of 17 [interquartile range (IQR) 10-27] and median age of 34 years [IQR = 25.0-52.0]. Hypofibrinogenemia was the predominant abnormality seen, (CCA Hypofibrinogenemia: 51/193, 26 %; ROTEM hypofibrinogenemia: 65/204, 32 %). Increased CCA derangement, the presence of ROTEM coagulopathy, worsening INR, worsening FibTEM and decreasing fibrinogen concentration, were all associated with both mortality and early massive transfusion. CONCLUSION: Clinically significant, multifaceted coagulopathy develops early in the clinical course, with hypofibrinogenemia being the predominant coagulopathy. In keeping with the ED literature, pre-hospital coagulation dysfunction was associated with mortality and early massive transfusion. Further work is required to identify strategies to identify and guide the pre-hospital management of the coagulation dysfunction seen in trauma.

Clot waveform analysis in acute promyelocytic leukemia.

The aim of this study was to evaluate the activated partial thromboplastin time (APTT) and prothrombin time (PT)-based clot waveform analysis (CWA) in patients diagnosed with acute promyelocytic leukemia (APL). APTT-based and PT-based CWA parameters of patients diagnosed with APL were analyzed and compared with healthy volunteers. Four APTT-CWA parameters were noted, maximum velocity corresponding to the first peak of the first derivative (max1), maximum acceleration corresponding to the first peak of the second derivative (max2) and the corresponding peak times of max1 and max2 (Tmax1, Tmax2). For the PT-CWA, two PT-CWA parameters were noted, maximum velocity (max1') and the corresponding timing (Tmax1'). The results were expressed in medians. Mann-Whitney U test was used to compare the CWA parameters. Correlations were examined using the Spearman correlation test. Tmax1 and Tmax2 were significantly prolonged in patients with APL in comparison with healthy volunteers. Although max1 and max2 were lower in APL patients compared with healthy volunteers, no significant difference was noted. There was a strong and significant correlation between the DIC score and the parameters max1, max2 and max1' and a very strong and significant correlation between fibrinogen levels and max1, max2 and max1'. When comparing DIC patients with hypofibrinogenemia and DIC without hypofibrinogenemia, a significant difference was noted in max1, max2, Tmax1 and Tmax2. The APTT and PT-based CWA analysis is a good tool to evaluate the bleeding tendency in APL, as it offers a novel approach for evaluating global hemostasis, predicting the bleeding risk and delivering improvements to APL patients management.

Prospective, Randomized Study of Fibrinogen Concentrate Versus Cryoprecipitate for Correcting Hypofibrinogenemia in Cardiac Surgery Patients.

OBJECTIVE: Cardiac surgery with cardiopulmonary bypass (CPB) is associated with hypofibrinogenemia and severe bleeding requiring transfusion. Guidelines recommend cryoprecipitate or fibrinogen concentrate (FC) for the treatment of acquired hypofibrinogenemia. This study compared cryoprecipitate and FC for the correction of acquired hypofibrinogenemia and the associated costs. DESIGN: A single-center, prospective, randomized study evaluating patients with hypofibrinogenemia after cardiac surgery. The primary endpoint was direct treatment cost. Secondary endpoints included the change in fibrinogen level after FC and/or cryoprecipitate dosing. SETTING: A single-center study in Astana, Kazakhstan. PARTICIPANTS: Participants who underwent CPB from 2021 to 2022 and developed clinically significant bleeding and hypofibrinogenemia. INTERVENTIONS: Patients were randomized to receive cryoprecipitate or FC. MEASUREMENTS AND MAIN RESULTS: Eighty-eight adult patients with acquired hypofibrinogenemia (<2.0 g/L) after CPB were randomized to receive cryoprecipitate (N = 40) or FC (N = 48), with similar demographics between groups. Overall, mean ± SD 9.33 ± 0.94 units (range, 8-10) cryoprecipitate or 1.40 ± 0.49 g (1-2) FC was administered to the 2 groups. From before administration to 24 hours after, mean plasma fibrinogen increased by a mean ± SD of 125 ± 65 and 96 ± 65 mg/dL in the cryoprecipitate and FC groups, respectively. At 48 hours after administration, there was no significant difference in fibrinogen levels between groups. The mean direct cost of treatment with FC was significantly lower than with cryoprecipitate (p < 0.0001): $1,505.06 ± $152.40 and $631.75 ± $223.67 per patient for cryoprecipitate and FC, respectively. CONCLUSION: Analysis of plasma fibrinogen concentration showed that cryoprecipitate and FC had comparable effectiveness. However, FC is advantageous over cryoprecipitate due to its ease of handling, lower cost, and high purity.

Nomogram for the prediction of tigecycline-induced hypofibrinogenaemia in a Chinese population.

BACKGROUND: Tigecycline has been widely used for multi-drug-resistant bacterial infections in China. Although many studies have reported the risk factors for tigecycline-induced hypofibrinogenaemia, it remains unknown whether valproic acid or voriconazole in combination with tigecycline is associated with the decrease in fibrinogen, as both drugs could lead to coagulation disorders. The aim of this study was to develop a nomogram for the prediction of tigecycline-induced hypofibrinogenaemia. METHODS: This was a multi-centre retrospective case-control study. The primary outcome was the accurate prediction of tigecycline-induced hypofibrinogenaemia. Nomograms were developed from logistic regression models with least absolute shrinkage and selection operator regression for variable selection. Model performance was assessed via calibration plots, and models were validated internally using bootstrapping on a validation cohort. RESULTS: In total, 2362 patients were screened, of which 611 were eligible for inclusion in this study. These 611 patients were divided into the training cohort (n=488) and the validation cohort (n=123). Predictors included in the nomogram for the total population were total dose, age, fibrinogen, prothrombin time (PT), comorbidity, and concomitant use of voriconazole. Total dose, fibrinogen, PT, activated partial thromboplastin time, white blood cell count, and concomitant use of voriconazole were selected to predict hypofibrinogenaemia in patients with malignant haematologic diseases. Both models were calibrated adequately, and their predictions were correlated with the observed outcome. The cut-offs for treatment duration in the total population and the subgroup were 10 and 6 days, respectively. CONCLUSIONS: Tigecycline in combination with voriconazole could increase the risk of hypofibrinogenaemia, and tigecycline-induced hypofibrinogenaemia is more likely to occur in patients with malignant haematologic diseases.

Interest in the new thromboelastometry device, Clot Pro®, for predicting thrombocytopenia and hypofibrinogenemia during lung transplantation.

INTRODUCTION: Lung transplantation is associated with high proportion of transfusion. Monitoring of coagulopathy using viscoelastic tests could aid in the perioperative management of bleeding. The aim of the study was to assess the predictive cut-off values for thrombocytopenia and hypofibrinogenemia using the new thromboelastography analyzer, ClotPro. METHODS: We retrospectively enrolled 65 patients who underwent lung transplantation and were sampled for both viscoelastic assays and conventional coagulation assays simultaneously during the procedure. We characterized the correlation between the EX-test (extrinsic pathway) and platelet count as well as between the FIB-test (extrinsic pathway after platelet inhibition) and fibrinogen concentration. Then, we used ROC curve analysis to determine the optimal EX-test and FIB-test values for predicting thrombocytopenia and hypofibrinogenemia. RESULTS: All the amplitude values of the EX-test (A5, A10, A20, MCF) showed correlation with platelets count (Spearman's rank correlation coefficient ranging from 0.75 to 0.77, all p < 0.0001). We also observed a strong correlation between the amplitude values of the FIB-test (A5, A10, A20 and MCF) and the fibrinogen concentration (Spearman's rank correlation coefficient ranging from 0.68 to 0.71, all p < 0.0001). The AUCs of the EX-test values for thrombocytopenia <100 G/L and <80 G/L ranged from 0.80 to 0.93. Similarly, the AUCs of the FIB-test values for hypofibrinogenemia <1.5 g/L and <2 g/L ranged from 0.74 to 0.83. These results indicate that only the five-minute parameter of thromboelastometry is sufficient for detecting thrombocytopenia and hypofibrinogenemia in patients undergoing lung transplantation. The proposed cut off values for the EX-test to predict thrombocytopenia <80 G/L showed high sensitivity (>86 %), high specificity (>89 %) and high negative predictive value (>95 %). FIB-test cut off values predictive of fibrinogen below 1.5 g/L showed sensitivity (>78 %), specificity (>55 %) and negative predictive value (>88 %). CONCLUSIONS: Our study provided preliminary results that are useful for developing a ClotPro-based algorithm to guide transfusion in lung transplantation. Future interventional studies will be necessary to validate these cut-off values of ClotPro for guiding transfusion.

Absence of Missense Variant Detection in Inherited Dysfibrinogenemia May Result from a Poor Raw Data Analysis Algorithm or Mosaicism.

Variant identification underlying inherited dysfibrinogenemia quite exceptionally fails. We report on two dysfibrinogenemia cases whose underlying DNA variant could not be identified by Sanger analysis. These failures result from two distinct mechanisms. The first case involved raw signal overcorrection by a built-in software, and the second constituted the first description of mosaicism for one of the fibrinogen genes. This mosaicism was subsequently identified by next-generation sequencing reanalysis of the sample.

[A Family with Congenital Dysfibrinogenemia and Blood Transfusion].

OBJECTIVE: To investigate a family with congenital dysfibrinogenemia, and analyze the risk of hemorrhage and thrombosis and blood transfusion strategies. METHODS: Prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) of the proband and her family members were detected by automatic coagulometer, fibrinogen (Fg) activity and antigen were detected by Clauss method and PT algorithm respectively. Meanwhile, thromboelastometry was analyzed for proband and her family members. Then, peripheral blood samples of the proband and her family members were collected, and all exons of FGA, FGB and FGG and their flanks were amplified by PCR and sequenced to search for gene mutations. RESULTS: The proband had normal APTT and PT, slightly prolonged TT, reduced level of Fg activity (Clauss method). The Fg of the proband's aunt, son and daughter all decreased to varying degrees. The results of thromboelastogram indicated that Fg function of the proband and her family members (except her son) was basically normal. Gene analysis showed that there were 6233 G/A (p.AαArg35His) heterozygous mutations in exon 2 of FGA gene in the proband, her children and aunt. In addition, 2 polymorphic loci were found in the family, they were FGA gene g.9308A/G (p.AαThr331Ala) and FGB gene g.12628G/A (p.BßArg478Iys) polymorphism, respectively. The proband was injected with 10 units of cryoprecipitate 2 hours before delivery to prevent bleeding, and no obvious bleeding occurred during and after delivery. CONCLUSION: Heterozygous mutation of 6233G/A (p.AαArg35His) of FGA gene is the biogenetic basis of the disease in this family with congenital dysfibrinogenemia.