Portal vein thrombosis in a patient with severe hemophilia B: A challenging balanced management.

Key Clinical Message: The increased life expectancy in patients with hemophilia (PwH) over the last years has raised the incidence of comorbidities, including thromboembolic events. Thromboembolic events are rare in PwH and most of them occur in the presence of exogenous risk factors. There is still scarce scientific evidence on the optimal antithrombotic treatment and management approach in this population. Abstract: In the hemophilic population thromboembolic events are rare. Most of them are often multifactorial and occur in the presence of both exogenous (orthopedic surgery, intensive replacement therapy, use of central venous catheters…) and endogenous (cardiovascular diseases) risk factors. We describe the case of a 43-year-old patient with severe hemophilia B (sHB) receiving prophylaxis with eftrenonacog alfa (rFIXFc) and antithrombotic treatment due to portal vein thrombosis. The patient was treated with extended half- life factor IX (EHL-FIX) prophylaxis maintaining higher trough levels to avoid new bleeding episodes associated to the underlying disease and the use of antithrombotic therapy with low molecular weight heparin. EHL-FIX concentrates allow prolonged intervals between intravenous infusions and higher hemostatic protection thanks to increased factor trough levels. This current case report provides clinical evidence in antithrombotic management in a patient with severe hemophilia B.

VHrare study: Prevalence, clinical features and management of severe rare bleeding disorders in a large cohort.

INTRODUCTION: Rare bleeding disorders (RBD) constitute 5% of total hereditary bleeding disorders, although the number could be higher, due to the presence of undiagnosed asymptomatic patients. The objective of this study was to analyze the prevalence and characteristics of patients with severe RBDs in our area. MATERIAL AND METHODS: We analyzed the patients with RBD followed at a tertiary-level hospital between January 2014 and December 2021. RESULTS: A total of 101 patients were analyzed, with a median age at diagnosis of 27.67 years (range 0-89), of which 52.47% were male. The most frequent RBD in our population was FVII deficiency. Regarding the diagnostic reason, the most frequent cause was a preoperative test and only 14.8% reported bleeding symptoms at the time of diagnosis. A genetic study was carried out in 63.36% of patients and the most frequent mutation type found was finding a missense mutation. CONCLUSIONS: The distribution of RBDs in our centre is similar to the one reported in the literature. The majority of RBDs were diagnosed from a preoperative test and this allowed preventive treatment prior to invasive procedures to avoid bleeding complications. 83% of patients did not have a pathological bleeding phenotype according to ISTH-BAT.

Prevalence and genotypic diversity of ostreid herpesvirus type 1 in Crassostrea gigas cultured in the Gulf of California, Mexico.

In bivalve mollusk aquaculture, massive disease outbreaks with high mortality and large economic losses can occur, as in northwest Mexico in the 1990s. A range of pathogens can affect bivalves; one of great concern is ostreid herpesvirus 1 (OsHV-1), of which there are several strains. This virus has been detected in the Gulf of California in occasional or sporadic samplings, but to date, there have been few systematic studies. Monthly samples of Crassostrea gigas, water, and sediment were taken in the La Cruz coastal lagoon and analyzed by PCR. The native mollusk, Dosinia ponderosa, which lives outside the lagoon, was sampled as a control. The virus was found throughout the year only in C. gigas, with prevalence up to 60%. In total, 9 genotype variants were detected, and genetic analysis suggests that linear genotypic evolution has occurred from strain JF894308, present in La Cruz in 2011. There has been no evidence of the entry of new viral genotypes in the recent past, thus confinement of the virus within the lagoons of the Gulf of California could promote a native genotypic diversity in the short term.