Bernard-Soulier syndrome (BSS) is a rare autosomal recessive bleeding disorder characterized by defects of the GPIb-IX-V complex, a platelet receptor for von Willebrand factor (VWF). Most of the mutations identified in the genes encoding for the GP1BA (GPIbα), GP1BB (GPIbβ), and GP9 (GPIX) subunits prevent expression of the complex at the platelet membrane or more rarely its interaction with VWF. As a consequence, platelets are unable to adhere to the vascular subendothelium and agglutinate in response to ristocetin. In order to collect information on BSS patients, we established an International Consortium for the study of BSS, allowing us to enrol and genotype 132 families (56 previously unreported). With 79 additional families for which molecular data were gleaned from the literature, the 211 families characterized so far have mutations in the GP1BA (28%), GP1BB (28%), or GP9 (44%) genes. There is a wide spectrum of mutations with 112 different variants, including 22 novel alterations. Consistent with the rarity of the disease, 85% of the probands carry homozygous mutations with evidence of founder effects in some geographical areas. This overview provides the first global picture of the molecular basis of BSS and will lead to improve patient diagnosis and management.

Because of the very short half-life of factor VII, prophylaxis in factor VII deficiency is considered a difficult endeavor. The clinical efficacy and safety of prophylactic regimens, and indications for their use, were evaluated in factor VII-deficient patients in the Seven Treatment Evaluation Registry. Prophylaxis data (38 courses) were analyzed from 34 patients with severe factor VII deficiency (<1-45 years of age, 21 female). Severest phenotypes (central nervous system, gastrointestinal, joint bleeding episodes) were highly prevalent. Twenty-one patients received recombinant activated factor VII (24 courses), four received plasma-derived factor VII, and ten received freshfrozen plasma. Prophylactic schedules clustered into "frequent" courses (three times weekly, n=23) and "infrequent" courses (≤2 times weekly, n=15). Excluding courses for menorrhagia, "frequent" and "infrequent" courses produced 18/23 (78%) and 5/12 (41%) "excellent" outcomes, respectively; relative risk, 1.88; 95% confidence interval, 0.93-3.79; P=0.079. Long-term prophylaxis lasted from 1 to >10 years. No thrombosis or new inhibitors occurred. In conclusion, a subset of patients with factor VII deficiency needed prophylaxis because of severe bleeding. Recombinant activated factor VII schedules based on "frequent" administrations (three times weekly) and a 90 mg/kg total weekly dose were effective. These data provide a rationale for long-term, safe prophylaxis in factor VII deficiency (clinicaltrials.gov: NCT01269138). Prophylaxis in congenital factor VII deficiency: indications, efficacy and safety. Results from the Seven Treatment Evaluation Registry (STER)

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Introduction: Surgery in patients with haemophilia B carries a high risk of excessive bleeding and requires adequate haemostatic control until wound healing. Nonacog beta pegol, a long-acting recombinant glycoPEGylated factor IX (FIX), was used in the perioperative management of patients undergoing major surgery. Aim: To evaluate the efficacy and safety of nonacog beta pegol in patients with haemophilia B who undergo major surgery. Methods: This was an open-label, multicentre, non-controlled surgery trial aimed at assessing peri-and postoperative efficacy and safety of nonacog beta pegol in 13 previously treated patients with haemophilia B. All patients received a preoperative nonacog beta pegol bolus injection of 80 IU kg À1. Postoperatively, the patients received fixed nonacog beta pegol doses of 40 IU kg À1, repeated at the investigator's discretion. Safety assessments included monitoring of immunogenicity and adverse events. Results: Intraoperative haemostatic effect was rated 'excellent' or 'good' in all 13 cases. Apart from the preoperative injection, none of the patients needed additional doses of nonacog beta pegol on the day of surgery. The median number of postoperative doses of nonacog beta pegol was 2.0 from days 1 to 6 and 1.5 from days 7 to 13. No unexpected intra-or postoperative complications were observed including deaths or thromboembolic events. No patients developed inhibitors. Conclusions: These results indicated that nonacog beta pegol was safe and effective in the perioperative setting, allowing major surgical interventions in patients with haemophilia B with minimal periand postoperative concentrate consumption and infrequent injections as reported with standard FIX products.

Chediak–Higashi syndrome (CHS) is caused by autosomal recessive mutations in LYST, resulting in enlarged lysosomal compartments in multiple cell types. CHS patients display oculocutaneous albinism and may develop life-threatening hemophagocytic lymphohistiocytosis (HLH). While NK cell-mediated cytotoxicity has been reported to be uniformly defective, variable defects in T cell-mediated cytotoxicity has been observed. The latter has been linked to the degree of HLH susceptibility. Since the discrepancies in NK cell- and T cell-mediated cellular cytotoxicity might result from differences in regulation of cytotoxic granule release, we here evaluated perforin-containing secretory lysosome size and number in freshly isolated lymphocytes from CHS patients and furthermore compared their exocytic capacities. Whereas NK cells from CHS patients generally contained a single, gigantic perforin-containing granule, cytotoxic T cells predominantly contained several smaller granules. Nonetheless, in a cohort of 21 CHS patients, cytotoxic T cell and NK cell granule exocytosis were similarly impaired upon activating receptor stimulation. Mechanistically, polarization of cytotoxic granules was defective in cytotoxic lymphocytes from CHS patients, with EEA1, a marker of early endosomes, mislocalizing to lysosomal structures. The results leads to the conclusion that lysosome enlargement corresponds to loss of distinct organelle identity in the endocytic pathway, which on a subcellular level more adversely affects NK cells than T cells. Hence, vesicular size or numbers do not per se dictate the impairment of lysosomal exocytosis in the two cell types studied.