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The emergence and attendant mortality of vaccine-induced immune thrombocytopenia and thrombosis (VITT) as a consequence of vaccination against severe acute respiratory syndrome coronavirus 2 have resulted in some patients with VITT being considered as deceased organ donors. Outcomes after kidney transplantation in this context are poorly described. Because the disease seems to be mediated by antiplatelet factor 4 antibodies, there is a theoretical risk of transmission via passenger leukocytes within the allograft.We analyzed the experience of kidney transplantation from donors with VITT in the United Kingdom between January and June 2021. We followed-up all recipients of kidney-only transplants from donors with VITT to detect major postoperative complications or features of disease transmission and assess graft survival and function.There were 16 kidney donors and 30 single kidney transplant recipients in our study period. Of 11 preimplantation biopsies, 4 showed widespread glomerular microthrombi. After a median of 5 mo, patient and graft survival were 97% and 90%, respectively. The median 3-mo estimated glomerular filtration rate was 51 mL/min/1.73 m 2 . Two recipients had detectable antiplatelet factor 4 antibodies but no evidence of clinical disease after transplantation. Major hemorrhagic complications occurred in 3 recipients, all of whom had independent risk factors for bleeding, resulting in the loss of 2 grafts. The involvement of VITT could not be completely excluded in one of these cases.The UK experience to date shows that favorable outcomes are possible after kidney transplantation from donors with VITT but highlights the need for ongoing vigilance for donor-related complications in these patients.

Acute thrombotic thrombocytopenic purpura (TTP) is a life-threatening emergency and plasma exchange (PEX) is the initial treatment shown to reduce acute mortality.To compare current practice in the United Kingdom (UK) against the standards set out in the 2012 British Society of Haematology guideline, and to better understand the issues affecting prompt initiation of PEX.The trainee research network HaemSTAR conducted a retrospective nationwide review of adults presenting to UK hospitals with a first episode of acute TTP.Data on 148 patients treated at 80 UK hospitals between 2014 and 2019 demonstrated that 64.8% of patients received PEX within 24 h. Diagnostic uncertainty was the most commonly cited reason for delayed treatment. Conversely, a shorter time to PEX occurred in patients who had red cell fragments or severe thrombocytopenia identified on their first complete blood count. Availability of on-site PEX was associated with a greater proportion of patients receiving PEX within 8 h compared to patients transferred, but by 24 h there was no difference between the two groups and two-thirds of all patients had received their first PEX. The mortality rate for patients that received PEX was 9.2%, with 27.8% of deaths linked to delayed treatment initiation.This is the first multi-center evaluation of treatment delays in acute TTP and it will inform targeted pathways to improve prompt access to life-saving intervention.

This guideline was compiled according to the British Societyof Haematology (BSH) process at https://b-s-h.org.uk/guidelines/proposing-and-writing-a-new-bsh-guideline/. The Grad-ing of Recommendations Assessment, Development and Evaluation (GRADE) nomenclature was used to evaluatelevels of evidence and to assess the strength of recommenda-tions. The GRADE criteria can be found at http://www.gradeworkinggroup.org

Vaccine-induced thrombosis and thrombocytopenia (VITT) may follow immunisation with the ChAdOx1 nCoV-19 vaccine against SARS-CoV-2. Autoantibodies to platelet factor 4 (PF4) may mediate VITT through antibody-dependent platelet activation, though the underlying etiology is uncertain. Anti-PF4 antibodies are also seen in heparin-induced thrombocytopenia, though most cases of VITT do not have prior heparin exposure. More than 20 million people in the United Kingdom (UK) have received the ChAdOx1 nCoV-19 vaccine.

The COVID-19 pandemic has resulted in the rapid development of a range of vaccines against SARS-CoV-2. Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is a rare but life-threatening complication of primarily adenoviral-based vaccines associated with the presence of antibodies to a PF4/polyanion neoepitope and measured by using enzyme-linked immunosorbent assays. Presented are serial anti–PF4/polyanion antibody, platelet, and D-dimer measurements in a large cohort of patients and their relation to relapse. Overall, 51% of patients using the Stago assay had persistently positive anti–PF4/polyanion levels 100 days’ postdiagnosis, whereas 94% of patients monitored by using the Immucor assay remain positive. The median duration of positivity of the PF4 assay is 87 days, with 72% of patients remaining positive after a median follow-up of 105 days. The use of plasma exchange seemed to reduce anti–PF4/polyanion levels and increase platelet counts in the acute setting more rapidly than other therapies. The rate of relapse in this study was 12.6%, with all relapsed cases exhibiting persistently positive PF4 antibodies and falling platelet counts. Only one patient had extension of their thrombosis. Overall, despite the persistence of PF4 antibodies in 72% of patients, the rate of relapse was low and did not seem to result in recrudescence of the aggressive clinical picture seen at index presentation. Monitoring of these patients in the UK cohort is ongoing and will aid in definition of the natural history of this novel condition.

Summary This document aims to provide practical guidance for the assessment and management of patients with thrombocytopenia, with a particular focus on immune thrombocytopenia (ITP), during the COVID‐19 pandemic. The intention is to support clinicians and, although recommendations have been provided, it is not a formal guideline. Nor is there sufficient evidence base to conclude that alternative approaches to treatment are incorrect. Instead, it is a consensus written by clinicians with an interest in ITP or coagulation disorders and reviewed by members of the UK ITP forum.

The level of venous thrombosis risk in women who experience spontaneous or induced pregnancy loss has previously been uncertain. However, recent data indicate that the risk of venous thrombosis in women undergoing pregnancy termination in the first trimester is increased two-fold compared to non-pregnant women but reduced five-fold compared to women in the 6 weeks following a term birth. The termination procedure itself appears not to influence thrombosis risk. In light of this data, this consensus statement provides recommendations for reducing the risk of venous thrombosis in women undergoing spontaneous or induced pregnancy loss based on Royal College of Obstetricians and Gynaecologists risk stratification guidelines.

This chapter explores the clinical features of vaccine-induced immune thrombotic thrombocytopenia, also called vaccine-induced immune thrombocytopenia and thrombosis (VITT). Whilst the etiology is distinct from other causes of thrombotic thrombocytopenia syndrome (TTS), presentation may be similar and hence the need for strict diagnostic criteria to ensure accurate and prompt diagnosis and early treatment. Studies have identified prognostic markers of the disease, directing therapy and management pathways, and mortality and morbidity from this rare but life-threatening and potentially disabling consequence of the ChAdOx1 nCov-19 vaccine has declined.

This review paper explores the potential psychiatric and psychological sequelae of vaccine-induced immune thrombotic thrombocytopenia, also called vaccine-induced immune thrombocytopenia, and thrombosis (VITT). In the absence of any literature to date we have extrapolated data from similar conditions, particularly data pertaining to the critical care population. We discuss both the direct and indirect effects of thrombosis, likely psychiatric and psychological challenges during recovery, and ethical issues around vaccination. We have also suggested a comprehensive guide to the psychiatric assessment and management of patients presenting with VITT with the aim of early identification of problems and maximizing rehabilitation potential and quality of life.

Background White blood cells (WBC) are commonly measured to investigate suspected infection and inflammation in pregnant women, but the pregnancy-specific reference interval is variably reported, increasing diagnostic uncertainty in this high-risk population. It is essential that clinicians can interpret WBC results in the context of normal pregnant physiology, given the huge global burden of infection on maternal mortality. Methods We performed a longitudinal, repeated measures population study of 24,318 pregnant women in Oxford, UK, to map the trajectory of WBC between 8-40 weeks of gestation. We defined 95% reference intervals (RI) for total WBC, neutrophils, lymphocytes, eosinophils, basophils, and monocytes for the antenatal and postnatal periods. Findings WBC were measured 80,637 times over five years. The upper reference limit for total WBC was elevated by 36% in pregnancy (RI 5.7-15.0×109/L), driven by a 55% increase in neutrophils (3.7-11.6×109/L) and 38% increase in monocytes (0.3-1.1×109/L), which remained stable between 8-40 weeks. Lymphocytes were reduced by 36% (1.0-2.9×109/L), while eosinophils and basophils were unchanged. Total WBC was elevated significantly further from the first day after birth (similar regardless of the mode of delivery), which resolved to pre-delivery levels by an average of seven days, and to pre-pregnancy levels by day 21. Interpretation There are marked changes in WBC in pregnancy, with substantial differences between cell subtypes. WBC are measured frequently in pregnant women in obstetric and non-obstetric settings, and results should be interpreted using a pregnancy-specific RI until delivery, and between days 7-21 after childbirth. Funding None.

BACKGROUND\ud \ud Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is a new syndrome associated with the ChAdOx1 nCoV-19 adenoviral vector vaccine against severe acute respiratory syndrome coronavirus 2. Data are lacking on the clinical features of and the prognostic criteria for this disorder.\ud \ud \ud \ud METHODS\ud \ud We conducted a prospective cohort study involving patients with suspected VITT who presented to hospitals in the United Kingdom between March 22 and June 6, 2021. Data were collected with the use of an anonymized electronic form, and cases were identified as definite or probable VITT according to prespecified criteria. Baseline characteristics and clinicopathological features of the patients, risk factors, treatment, and markers of poor prognosis were determined.\ud \ud \ud \ud RESULTS\ud \ud Among 294 patients who were evaluated, we identified 170 definite and 50 probable cases of VITT. All the patients had received the first dose of ChAdOx1 nCoV-19 vaccine and presented 5 to 48 days (median, 14) after vaccination. The age range was 18 to 79 years (median, 48), with no sex preponderance and no identifiable medical risk factors. Overall mortality was 22%. The odds of death increased by a factor of 2.7 (95% confidence interval [CI], 1.4 to 5.2) among patients with cerebral venous sinus thrombosis, by a factor of 1.7 (95% CI, 1.3 to 2.3) for every 50% decrease in the baseline platelet count, by a factor of 1.2 (95% CI, 1.0 to 1.3) for every increase of 10,000 fibrinogen-equivalent units in the baseline d-dimer level, and by a factor of 1.7 (95% CI, 1.1 to 2.5) for every 50% decrease in the baseline fibrinogen level. Multivariate analysis identified the baseline platelet count and the presence of intracranial hemorrhage as being independently associated with death; the observed mortality was 73% among patients with platelet counts below 30,000 per cubic millimeter and intracranial hemorrhage.\ud \ud \ud \ud CONCLUSIONS\ud \ud The high mortality associated with VITT was highest among patients with a low platelet count and intracranial hemorrhage. Treatment remains uncertain, but identification of prognostic markers may help guide effective management. (Funded by the Oxford University Hospitals NHS Foundation Trust.)

The COVID-19 pandemic has resulted in the development of highly effective vaccines that provide hope to the global community for reducing the spread of SARS-CoV-2 and limiting the mortality and morbidity caused by the disease. These vaccines have been produced using differing technologies, taken through clinical trials, and rolled out across the UK at unprecedented speed. However, the recent emergence of rare cases of life-threatening thrombosis in association with thrombocytopenia has threatened to derail one particular vaccine, the Oxford AstraZeneca ChAdOx1 vaccine, upon which many countries are dependent for their vaccination programmes. The story of how this situation has been managed in the UK at the height of the vaccine roll-out represents a remarkable collective endeavour on the part of the haematology community, working closely with other acute medical and surgical professionals within the NHS and the UK health regulatory bodies, to provide rapid expert guidance that has saved lives and helped keep the national vaccination programme on track.

Summary The COVID‐19 pandemic has created many challenges in the management of immune thrombocytopenic purpura (ITP). The recommendation for avoidance of steroids by WHO led to the off‐licence use, supported by NHS England, of thrombopoietin mimetics (TPO‐RA) for newly diagnosed or relapsed ITP. This is a real‐world prospective study which investigated the treatment patterns and outcomes in this setting. Twenty‐four hospitals across the UK submitted 343 cases. Corticosteroids remain the mainstay of ITP treatment, but TPO‐RAs were more effective. Incidental COVID‐19 infection was identified in a significant number of patients (9·5%), while 14 cases were thought to be secondary to COVID‐19 vaccination.

Introduction Vaccine-induced immune thrombocytopenia and thrombosis (VITT) following ChAdOx1 nCOV-19 vaccine has been described, associated with unusual site thrombosis, thrombocytopenia, raised D-dimer, and high-titer immunoglobulin-G (IgG) class anti-platelet factor 4 (PF4) antibodies. Enzyme-linked immunosorbent assays (ELISA) have been shown to detect anti-PF4 in patients with VITT, but chemiluminescence assays do not reliably detect them. ELISA assays are not widely available in diagnostic laboratories, and, globally, very few laboratories perform platelet activation assays. Methods Assays that are commercially available in the United Kingdom were evaluated for their ability to identify anti-PF4 antibodies in samples from patients with suspected VITT. Four IgG-specific ELISAs, two polyspecific ELISAs, and four rapid assays were performed on samples from 43 patients with suspected VITT from across the United Kingdom. Cases were identified after referral to the UK Expert Haematology Panel multidisciplinary team and categorized into unlikely, possible, or probable VITT. Results and discussion We demonstrated that the HemosIL AcuStar HIT-IgG, HemosIL HIT-Ab, Diamed PaGIA gel, and STic Expert assays have poor sensitivity for VITT in comparison to ELISA. Where these assays are used for heparin-induced thrombocytopenia (HIT) diagnosis, laboratories should ensure that requests for suspected VITT are clearly identified so that an ELISA is performed. No superiority of IgG-ELISAs over polyspecific ELISAs in sensitivity to VITT could be demonstrated. No single ELISA method detected all possible/probable VITT cases; if a single ELISA test is negative, a second ELISA or a platelet activation assay should be considered where there is strong clinical suspicion.

Thrombocytopenia is common in an intensive care unit (ICU) setting due to endogenous and iatrogenic factors. Despite that, thrombocytopenia in patients with severe COVID-19 infections is surprisingly uncommon. By examining the blood film of 20 ICU patients with COVID-19, we observed the presence of platelet aggregates and macrothrombocytes indicating increased platelet activity. We compared these findings with 20 blood films of non-severe COVID-19 cases where these findings were absent. These morphology features could be consistent with severe COVID-19 infection and is further evidence of the important role that platelets play when COVID-19 manifests with thrombotic complications or respiratory failure.

Transfusion of an incorrect blood component is an important avoidable serious hazard of transfusion resulting from process errors. Our group and others have taken advantage of new technology and developed electronic transfusion systems for safe transfusion practice in a previous studies. They allow the clinical staff to correctly identify the patient and the blood product at the bedside, ensuring the right blood product is given to the right patient. This video is to demonstrate the process and not to promote any specific product. It is a follow up our previous video clip on electronic remote blood issue in a previous study. The process for correct patient identification originates from the wristband, which contains the patient identification details in a 2D barcode and is printed from the electronic patient record system. These details are associated with the blood sample through using a portable printer to produce a label for the sample tube. The patient details are scanned into the blood bank laboratory information system (LIS) and are then printed on a compatibility label by the LIS, which also contains a 2-dimensional barcode, and is then attached to the blood product. Following an initial visual check of these details by the clinical staff, the electronic bedside system requires that both the patient wristband barcode and the blood product compatibility barcode are scanned. This will electronically verify at the patient's bedside that the right unit is to be given to the right patient. This is the final step in ensuring end-to-end electronic control and safe transfusion practice.

Inherited and acquired bleeding disorders pose significant hemostatic challenges for surgery. Patients at particular risk of bleeding include those with inherited bleeding disorders such as hemophilia, von Willebrand disease, and platelet function defects; those on antiplatelet agents or anticoagulants; and those with acquired conditions such as immune thrombocytopenic purpura, liver disease, or renal impairment. Each has its own specific challenges and close collaboration between the anesthetic, surgical, and hematology teams is crucial. Optimizing surgical hemostasis for patients at risk involves attention to detail, with careful preoperative planning, meticulous surgical technique, prompt identification of complications and judicious use of hemostatic agents and blood components. This article gives an overview of the bleeding risks involved and therapeutic options to overcome them.

Background Iron deficiency anaemia in pregnancy is common and is a major cause of maternal and neonatal morbidity worldwide. Serum ferritin is the current gold standard test for identifying iron depletion, with a cut-off value of 30 µg/L. Recent studies in low- and middle-income countries have identified mean cell haemoglobin concentration as a surrogate marker for the prediction of iron depletion. Methods We studied values from 786 antenatal blood results from 2018 in Oxford, UK, and correlated the red cell indices with serum ferritin measurements. Results Haemoglobin, mean cell volume, mean cell haemoglobin and mean cell haemoglobin concentration have low specificity and sensitivity for the identification of iron depletion. Conclusions We found that haemoglobin, mean cell volume, mean cell haemoglobin and mean cell haemoglobin concentration do not have sufficient predictive value in this population to be used as a screening test for non-anaemic iron depletion.

What you need to know The UK vaccination programme has prevented thousands of deaths from infection with SARS-CoV-2, but has been accompanied by new vaccine related complications. The most serious of these is a novel disorder, described as vaccine induced immune thrombocytopenia and thrombosis (VITT). This immune mediated condition is caused by development of pathological anti-platelet factor 4 (PF4) antibodies following vaccination against covid-19, which leads to intense activation of platelets and the coagulation system. The subsequent clinical syndrome often presents with life threatening thrombosis and secondary haemorrhage, which are challenging to manage in the context of new biochemical coagulopathy. This article summarises the most recent recommendations from the rapid covid-19 guideline produced by the National Institute for Health and Care Excellence (NICE).1 NICE recommendations are based on systematic reviews of best available evidence. This guideline was developed using an interim process and methods for guidelines developed in response to health and social care emergencies. These included convening an independent advisory expert panel, scoping, identifying, and reviewing …

Bleeding diatheses due to platelet-related disorders can present challenges to treating clinicians, especially in the context of peri- and post-partum patients in the obstetric setting. Thrombocytopenia and Absent-Radii syndrome (TARS) is an inherited disorder characterized by reduced bone marrow platelet production, skeletal deformities affecting radii and other limbs; cardiac, renal, and other heterogeneous anomalies may occur. It is caused by the co-inheritance of a microdeletion and a nucleotide polymorphism in the RBM8A gene on chromosome 1. Bleeding phenotype is more severe than platelet numbers which might predict especially in infants but improves with age. There is minimal literature regarding the impact of pregnancy and puerperium. We describe the management of three pregnancies in the hematology-obstetrics clinic. As platelet counts normally decrease through pregnancy, close monitoring is required in TARS. No major bleeding was seen antenatally but two required platelet transfusions during labor. No other treatment definitely improves bleeding, although case reports of steroids claim variable success. Tranexamic acid may be helpful, and thrombopoietin agonists represent a potential future option.