Summary
Coagulation dysfunction and thrombosis are major complications in patients with coronavirus disease 2019 (COVID‐19). Patients on oral anticoagulants (OAC) prior to diagnosis of COVID‐19 may ...therefore have better outcomes. In this multicentre observational study of 5 883 patients (≥18 years) admitted to 26 UK hospitals between 1 April 2020 and 31 July 2020, overall mortality was 29·2%. Incidences of thrombosis, major bleeding (MB) and multiorgan failure (MOF) were 5·4%, 1·7% and 3·3% respectively. The presence of thrombosis, MB, or MOF was associated with a 1·8, 4·5 or 5·9‐fold increased risk of dying, respectively. Of the 5 883 patients studied, 83·6% (n = 4 920) were not on OAC and 16·4% (n = 963) were taking OAC at the time of admission. There was no difference in mortality between patients on OAC vs no OAC prior to admission when compared in an adjusted multivariate analysis hazard ratio (HR) 1·05, 95% confidence interval (CI) 0·93–1·19; P = 0·15 or in an adjusted propensity score analysis (HR 0·92 95% CI 0·58–1·450; P = 0·18). In multivariate and adjusted propensity score analyses, the only significant association of no anticoagulation prior to diagnosis of COVID‐19 was admission to the Intensive‐Care Unit (ICU) (HR 1·98, 95% CI 1·37–2·85). Thrombosis, MB, and MOF were associated with higher mortality. Our results indicate that patients may have benefit from prior OAC use, especially reduced admission to ICU, without any increase in bleeding.
Introduction
von Willebrand disease (VWD) is an inherited bleeding disorder caused by a quantitative or qualitative dysfunction of von Willebrand factor. Clinicians, patients and other stakeholders ...have many questions about the diagnosis and management of the disease.
Aim
To identify topics of highest importance to stakeholders that could be addressed by guidelines to be developed by the American Society of Hematology (ASH), the International Society on Thrombosis and Haemostasis (ISTH), the National Hemophilia Foundation (NHF) and the World Federation of Hemophilia (WFH).
Methods
A survey to determine and prioritize topics to be addressed in the collaborative development of guidelines for VWD was distributed to international stakeholders including patients, caregivers and healthcare providers (HCPs). Representatives of the four organizations coordinated the distribution strategy. The survey focused on both diagnosis and management of VWD, soliciting 7‐point Likert‐scale responses and open‐ended comments, in English, French and Spanish. We conducted descriptive analysis with comparison of results by stakeholder type, gender and countries' income classification for the rating questions and qualitative conventional content data analysis for the open‐ended responses.
Results
A total of 601 participants responded to the survey (49% patients/caregivers and 51% healthcare providers). The highest priority topics identified were diagnostic criteria/classification, bleeding assessment tools and treatment options for women and surgical patients. In contrast, screening for anaemia and differentiating plasma‐derived therapy versus recombinant therapies received lower ratings.
Conclusion
This survey highlighted areas of importance to a diverse representation of stakeholders in the diagnosis and management of VWD, providing a framework for future guideline development and implementation.
Inherited defects of platelet function disorders are rare and difficult to diagnose due to lack of standardized platelet tests. An aspirin-like platelet defect is characterised by reduced thromboxane ...A2 (TXA2) signalling due to a defect in the arachidonic acid (AA) pathway in platelets. Patients with aspirin-like defect present with mild to moderate bleeding symptoms and impaired platelet aggregation responses to AA and ADP. This is similar to the irreversible effect of aspirin on platelets, which is mediated through inhibition of prostaglandin H synthase-1 also known as cyclooxygenase-1 (PTGS1/COX1). We for the first time report platelet function disorders due to autosomal recessive inheritance of variants in PTGS1.
In a total of 3563 cases with bleeding disorders, comprising 1169 whole genome sequenced probands of the BRIDGE-BPD study and 2394 panel sequenced index cases of the ThromboGenomics cohort, we identified 15 unrelated cases of each cohort with an aspirin-like platelet function defect. Two of these cases had rare a variants in PTGS1, the gene encoding COX-1, which catalyses the conversion of arachidonic acid to prostaglandin H2. The first case presented with epistaxis and peri-operative bleeding. She had reduced platelet aggregation responses to arachidonic acid, ADP, collagen and epinephrine. Incubation of control blood with collagen resulted in enhanced levels of thromboxane B2, PGD2, PGE2, 11-HETE and 15-HETE which was absent in the index case.We identified a homozygous missense variant in PTGS1, p.Trp322Ser with a Combined Annotation Dependant Depletion Score (CADD) of 31.0. This variant was absent from GnomAD. The variant co-segregated in an autosomal recessive inheritance mode, with aspirin-like defect phenotype in the seven family members who were investigated. PTGS1 was not expressed on the platelets by western blot. Immunophenotyping demonstrated absence on the platelet surface but presence on neutrophils. The second case of the presented with menorrhagia, nosebleeds, easy bleeding and bruising. She had reduced aggregation responses to arachidonic acid, ADP, collagen and epinephrine. We identified two variants in cis: a splice-donor variant (g. 125133553 T>A), CADD 24.3; and an upstream non-coding variant (g. 125132069 C>G), CADD 16.63. The frequency of these variants were respectively; 1.7 x 10-5 and 8 x 10-3 in GnomAD. Platelet RNA and protein expression studies in the propositus revealed alternative splicing with the generation of a smaller protein due the splice variant. In contrast, the non coding variant had no effect on promoter or enhancer activity and therefore, is likely benign. In this case, the mode of inheritance is autosomal dominant with a dominant negative effect, which has been reported previously. For the other 13 cases of the Bridge-BPD study we also interrogated the non-coding space and interactors in the arachidonic acid pathway, none of which had genetic variants explaining the phenotype. For the 15 ThromboGenomics cohort cases because they were sequenced on targeted platform similar investigations could not take place. These cases could have a non inherited cause for the platelet defect or it is also permissible that variation in a hitherto undefined pathways unique to individual cases might be causal.
In conclusion, we for the first time report autosomal recessive inheritance of variants in PTGS1 as cause for a rare inherited bleeding disorder. The effect of the mutation are selective loss of expression of PTGS1 within platelets and decreased enzyme function. Two previous reports demonstrated autosomal dominant inheritance. The first demonstrated autosomal dominant inheritance of variants in PTGS1 as modifier in a well characterized family with haemophilia A and platelet function disorder (Nance et al JTH 2016). The second reported rare heterozygous variants in PTGS1 in two cases with a bleeding tendency which was not further specified in the report (Bastida et al Haematologica 2018).
Laffan:Pfizer: Honoraria; Roche: Consultancy, Speakers Bureau.
Understanding potential provocations of haemorrhage is important in a range of clinical settings, and particularly for people with abnormal vasculature. Patients with hereditary haemorrhagic ...telangiectasia (HHT) can report haemorrhage from nasal telangiectasia in real time, and suggested dietary factors may precipitate nosebleeds. To examine further, nosebleed severity, dietary supplement use, and blood indices were evaluated in an unselected group of 50 HHT patients recruited from a specialist UK service. Using the validated Epistaxis Severity Score, nosebleed severity ranged from 0 to 9.1 out of 10 (median 3.9). Using a Food Frequency Questionnaire, 24/50 (48%) participants reported use of dietary supplements in the previous year. A third (18/50; 36%) had used self prescribed, non-iron containing dietary supplements, ingesting between 1 and 3 different supplements each day. Eight (16%) used fish oils. Despite having more severe epistaxis (p = 0.012), the 12 iron supplement users had higher serum iron concentrations, and were able to maintain their red blood cell indices. In contrast, there was no evident benefit for the participants using non iron supplements. Furthermore, platelet counts and serum fibrinogen tended to be lower in fish oil/supplement users, and one fish oil user demonstrated reduced in vitro platelet aggregation. In conclusion, in this small study, a third of HHT patients used non-iron dietary supplements, and one in six ingested fish oils, unaware of their known anti-platelet activity. The scale of use, and potential of these "natural health supplements" to exacerbate nosebleeds has not been appreciated previously in HHT.
Background Pulmonary first pass filtration of particles marginally exceeding ~7 mu m (the size of a red blood cell) is used routinely in diagnostics, and allows cellular aggregates forming or ...entering the circulation in the preceding cardiac cycle to lodge safely in pulmonary capillaries/arterioles. Pulmonary arteriovenous malformations compromise capillary bed filtration, and are commonly associated with ischaemic stroke. Cohorts with CT-scan evident malformations associated with the highest contrast echocardiographic shunt grades are known to be at higher stroke risk. Our goal was to identify within this broad grouping, which patients were at higher risk of stroke. Methodology 497 consecutive patients with CT-proven pulmonary arteriovenous malformations due to hereditary haemorrhagic telangiectasia were studied. Relationships with radiologically-confirmed clinical ischaemic stroke were examined using logistic regression, receiver operating characteristic analyses, and platelet studies. Principal Findings Sixty-one individuals (12.3%) had acute, non-iatrogenic ischaemic clinical strokes at a median age of 52 (IQR 41-63) years. In crude and age-adjusted logistic regression, stroke risk was associated not with venous thromboemboli or conventional neurovascular risk factors, but with low serum iron (adjusted odds ratio 0.96 95% confidence intervals 0.92, 1.00), and more weakly with low oxygen saturations reflecting a larger right-to-left shunt (adjusted OR 0.96 0.92, 1.01). For the same pulmonary arteriovenous malformations, the stroke risk would approximately double with serum iron 6 mu mol/L compared to mid-normal range (7-27 mu mol/L). Platelet studies confirmed overlooked data that iron deficiency is associated with exuberant platelet aggregation to serotonin (5HT), correcting following iron treatment. By MANOVA, adjusting for participant and 5HT, iron or ferritin explained 14% of the variance in log-transformed aggregation-rate (p = 0.039/p = 0.021). Significance These data suggest that patients with compromised pulmonary capillary filtration due to pulmonary arteriovenous malformations are at increased risk of ischaemic stroke if they are iron deficient, and that mechanisms are likely to include enhanced aggregation of circulating platelets.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Ce numéro explore la relation entre langue, religion, politique et modernité dans l’espace musulman entre le XVIIe et le XXIe siècles. Dans quelle mesure la circulation des langues éclaire-t-elle les ...contextes politiques et culturels, les relations entre les groupes ethniques, les enjeux des conflits linguistiques ? Quels rôles a joué la langue arabe dans les différentes parties du monde musulman, en Afrique, Asie ou au Moyen-Orient ? Quels ont été les mouvements qui ont voulu « moderniser » et « réformer » les langues locales pour en faire des instruments du « progrès » ? Portant sur différents pays et zones géographiques (Afrique du Nord, Afrique de l’Est, Asie centrale, Cameroun, Égypte, Inde du Nord, Indonésie, Pakistan, Turquie) les contributions analysent les différents types de coexistence et de relation entretenues entre les différentes langues qui ont véhiculé et véhiculent l’islam (anglais, arabe, fulfulde, malais, ourdou, ouzbek, persan, sindhi, swahili, turc, etc.). Elles s’intéressent plus particulièrement aux processus de vernacularisation et de développement des langues locales au contact des langues de religion, à la relation entre dynamiques religieuses et dynamiques ethno-nationales, aux nouvelles formes d’expression du religieux et du séculaire.
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