Thrombocytopenia Secondary to COVID-19 Vaccination: Side Effect or Coincidence?

  While widespread coronavirus disease 2019 (COVID-19) vaccination has helped achieve some control of the pandemic, vaccines have presented with side effects of their own, both common and rare. We present an unusual case of a 66-year-old who presented with severe thrombocytopenia following vaccination with the Pfizer-BioNTech mRNA vaccine. Our patient is a 66-year-old African American female with a known history of Sjogren's syndrome and hepatitis C who presented to our facility as a direct admit from our affiliated infusion clinic where routine lab work revealed a platelet count of 14,000. On arrival, she reported a one-month history of progressive tiredness, intermittent epistaxis, and bruising on her legs. Her physical exam was notable for multiple petechiae and non-palpable purpura on all four extremities. Further questioning revealed that she had received her COVID-19 vaccine booster (Pfizer-BioNTech) three weeks prior to presentation and that is when all the symptoms had started. Rheumatology was consulted and the patient was started on intravenous immunoglobulin infusion for two days and pulse dose prednisone. Her platelet count showed improvement after treatment, and she was discharged home with a platelet count of 42,000. Though largely safe and efficacious, COVID-19 vaccines can present with rare systemic side effects and physicians must have a high index of suspicion and report these cases so that more data is available for interpretation.

[Recent topics in the pathophysiology and treatment of immune thrombocytopenic purpura].

Increased and impaired platelet productions via immunological abnormalities are the main pathophysiological mechanisms of primary immune thrombocytopenia (ITP). Recent studies have revealed that platelet removal from circulation involves not only Fc receptor-mediated phagocytosis of immunoglobulin G autoantibodies-bound platelets but also complement-dependent mechanism and platelet glycoprotein desialylation. Understanding the molecular mechanism of ITP pathophysiology has helped develop many novel molecular targeted drugs, and recent clinical trials have shown their effectiveness. In particular, fostamatinib, which is a Syk inhibitor, inhibits macrophage and B-cell activity and is already been approved in Europe for multidrug-resistant ITP. Recently, coronavirus disease-2019 (COVID-19) vaccine-associated newly-onset or ITP exacerbation has come to attention. Whether COVID-19 vaccines induce de novo ITP remains controversial. However, close attention is necessary after COVID-19 vaccination because a certain number of patients with ITP presented exacerbation after COVID-19 vaccination.

Mixed Warm and Cold Autoimmune Hemolytic Anemia With Concomitant Immune Thrombocytopenia Following Recent SARS-CoV-2 Infection and Ongoing Rhinovirus Infection.

Mixed-type autoimmune hemolytic anemia (AIHA) is a term used to describe hemolysis occurring in the context of both warm and cold reactive autoantibodies to red blood cells. Immune thrombocytopenia (ITP) is an acquired form of thrombocytopenia potentially complicated by hemorrhage due to autoantibodies reactive with platelets and megakaryocytes. Diagnosis of ITP requires exclusion of other known causes of thrombocytopenia. AIHA and ITP may be primary disorders or associated with lymphoproliferative, autoimmune, or viral infections. Here, we report a rare case of simultaneous mixed-type autoimmune hemolytic anemia with immune thrombocytopenia following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection treated with Paxlovid followed by Rhinovirus infection.

Knowledge mapping of immune thrombocytopenia: a bibliometric study.

Background: Immune thrombocytopenia (ITP) is an autoimmune disease characterized by isolated thrombocytopenia. Recently, the pathophysiology and novel drugs of ITP have been the focus of researchers with plenty of publications emerging. Bibliometrics is the process of extracting measurable data through statistical analysis of published research studies to provide an insight into the trends and hotspots. Objective: This study aimed to provide an insight into developing trends and hotspots in the field of ITP by bibliometric analysis. Methods: By using three bibliometric mapping tools (bibliometrix R package, VOSviewer, CiteSpace), we summarized the overview information of retrieved publications, as well as the analysis of keyword co-occurrence and reference co-citation. Results: A total of 3299 publications with 78066 citations on ITP research were included in the analysis. The keyword co-occurrence network identified 4 clusters relating to the diagnosis, pathophysiology, and treatment of ITP respectively. Then the reference co-citation analysis produced 12 clusters with a well-structured and highly credible clustering model, and they can be divided into 5 trends: second-line treatment, chronic ITP, novel therapy and pathogenesis, COVID-19 vaccine. Treg cells, spleen tyrosine kinase, and mesenchymal stem cells were the latest hotspots with strong burstness. Conclusion: This bibliometric analysis provided a comprehensive insight into research hotspots and trends on ITP, which would enrich the review of the ITP research.

Immune Thrombocytopenia Onset and Relapse During the COVID-19 Pandemic. A Monocenter Study.

Background And Objectives: Several infections and vaccinations can provoke immune thrombocytopenia (ITP) onset or relapse. Information on ITP epidemiology and management during the Covid-19 pandemic is scarce. In a large monocenter ITP cohort, we assessed the incidence and risk factors for: 1) ITP onset/relapse after Covid19 vaccination/infection; 2) Covid19 infection. Methods: Information on the date/type of anti-Covid-19 vaccine, platelet count before and within 30 days from the vaccine, and date/grade of Covid-19 was collected via phone call or during hematological visits. ITP relapse was defined as a drop in PLT count within 30 days from vaccination, compared to PLT count before vaccination that required a rescue therapy OR a dose increase of an ongoing therapy OR a PLT count <30 ×109/L with ≥20% decrease from baseline. Results: Between February 2020 and January 2022, 60 new ITP diagnoses were observed (30% related to Covid-19 infection or vaccination). Younger and older ages were associated with a higher probability of ITP related to Covid19 infection (p=0.02) and vaccination (p=0.04), respectively. Compared to Covid-19-unrelated ITP, Infection- and vaccine-related ITP had lower response rates (p=0.03) and required more prolonged therapy (p=0.04), respectively. Among the 382 patients with known ITP at the pandemic start, 18.1% relapsed; relapse was attributed to Covid-19 infection/vaccine in 52.2%. The risk of relapse was higher in patients with active disease (p<0.001) and previous vaccine-related relapse (p=0.006). Overall, 18.3% of ITP patients acquired Covid19 (severe in 9.9%); risk was higher in unvaccinated patients (p<0.001). Conclusions: All ITP patients should receive ≥1 vaccine dose and laboratory follow-up after vaccination, with a case-by-case evaluation of completion of the vaccine program if vaccine-related ITP onset/relapse and with tempest initiation of antiviral therapy in unvaccinated patients.

Successful Systemic Lysis Therapy of a Floating Carotid Thrombus in an Acute Stroke Patient with Known Immune Thrombocytopenia (ITP) on Ongoing Eltrombopag Therapy and Acute COVID-19 Infection: a Case Report.

Patients with immune thrombocytopenia (ITP) under eltrombopag therapy are vulnerable to thrombotic disbalance, both due to the disease itself and therapy-related hypercoagulability. Vascular events such as the development of a free-floating carotid thrombus are known rare complications of acute COVID-19 infections due to endothelial inflammation and presumptive underlying hypercoagulable state. In patients at risk, the onset of new focal neurological symptoms should prompt immediate angiographic diagnostics and, if necessary, appropriate treatment. Here, we report a case of a 38-year-old female with a medical history of ITP and the presence of COVID-19 infection presenting an acute sensorimotor hemiparesis of the right side while on eltrombopag therapy. Initial CT angiography revealed a free-floating thrombus in the left common carotid artery. Upon admission, the patient's platelet count was significantly elevated at 896 × 109/l. After systemic lysis therapy, the thrombus was fully dissolved. Follow-up diffusion-weighted imaging revealed multilocular cortical infarction of the left MCA territory. The patient soon recovered and was discharged with residual mild sensorimotor deficits in the right arm. Eltrombopag was paused at admission, and the patient's platelet count was quickly returning to normal. She was discharged with a daily intake of acetylsalicylic acid, a reduced daily dose of eltrombopag, and weekly monitoring of her platelet count for the next three months. This unique case highlights the need for caution in patients at vascular risk who contract COVID-19 and discusses thrombocytic derailment under thrombopoietin receptor agonist therapy in the context of an acute COVID-19 infection.

[Recent Advances in SARS-CoV-2-Induced Immune Thrombocytopenia --Review].

SARS-CoV-2-induced immune thrombocytopenia (SARS-CoV-2-induced ITP) is an autoimmune disease secondary to virus infections. Its diagnosis is often based on exclusion of other possible causes of thrombocytopenia in COVID-19 patients. Common laboratory examinations include coagulation function, thrombopoietin and drug-dependent antibodies. Since both bleeding and thrombosis risks are seen in SARS-CoV-2-induced ITP patients, individual remedy is essential for the treatment of this disease. Because thrombopoietin receptor agonist(TPO-RA) has the side effect of accelerating thrombosis and may aggravate the pulmonary embolism symptoms of patients, it should be used for refractory SARS-CoV-2-induced ITP patients only. This review briefly summarizes the recent research progress in the pathogenesis, diagnosis and treatment of SARS-CoV-2-induced ITP.

Thrombotic and Thromboembolic Complications After Vaccination Against COVID-19: A Systematic Review.

Thromboembolic complications after the COVID-19 vaccination have been reported from all over the world. We aimed to identify the thrombotic and thromboembolic complications that can arise after receiving various types of COVID-19 vaccines, their frequency, and distinguishing characteristics. Articles published in Medline/PubMed, Scopus, EMBASE, Google Scholar, EBSCO, Web of Science, the Cochrane Library, the CDC database, the WHO database, ClinicalTrials.gov, and servers like medRxiv.org and bioRxiv.org, as well as the websites of several reporting authorities between December 1, 2019, and July 29, 2021, were searched. Studies were included if they reported any thromboembolic complications post-COVID-19 vaccination and excluded editorials, systematic reviews, meta-analyses, narrative reviews, and commentaries. Two reviewers independently extracted the data and conducted the quality assessment. Thromboembolic events and associated hemorrhagic complications after various types of COVID-19 vaccines, their frequency, and distinguishing characteristics were assessed. The protocol was registered at PROSPERO (ID-CRD42021257862). There were 59 articles, enrolling 202 patients. We also studied data from two nationwide registries and surveillance. The mean age of presentation was 47 ± 15.5 (mean ± SD) years, and 71.1% of the reported cases were females. The majority of events were with the AstraZeneca vaccine and with the first dose. Of these, 74.8% were venous thromboembolic events, 12.7% were arterial thromboembolic events, and the rest were hemorrhagic complications. The most common reported event was cerebral venous sinus thrombosis (65.8%), followed by pulmonary embolism, splanchnic vein thrombosis, deep vein thrombosis, and ischemic and hemorrhagic stroke. The majority had thrombocytopenia, high D-dimer, and anti-PF4 antibodies. The case fatality rate was 26.5%. In our study, 26/59 of the papers were of fair quality. The data from two nationwide registries and surveillance revealed 6347 venous and arterial thromboembolic events post-COVID-19 vaccinations. COVID-19 vaccinations have been linked to thrombotic and thromboembolic complications. However, the benefits far outweigh the risks. Clinicians should be aware of these complications because they may be fatal and because prompt identification and treatment can prevent fatalities.

Potential mechanisms of vaccine-induced thrombosis.

Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is a rare syndrome characterized by high-titer anti-platelet factor 4 (PF4) antibodies, thrombocytopenia and arterial and venous thrombosis in unusual sites, as cerebral venous sinuses and splanchnic veins. VITT has been described to occur almost exclusively after administration of ChAdOx1 nCoV-19 and Ad26.COV2.S adenovirus vector- based COVID-19 vaccines. Clinical and laboratory features of VITT resemble those of heparin-induced thrombocytopenia (HIT). It has been hypothesized that negatively charged polyadenylated hexone proteins of the AdV vectors could act as heparin to induce the conformational changes of PF4 molecule that lead to the formation of anti-PF4/polyanion antibodies. The anti-PF4 immune response in VITT is fostered by the presence of a proinflammatory milieu, elicited by some impurities found in ChAdOx1 nCoV-19 vaccine, as well as by soluble spike protein resulting from alternative splice events. Anti-PF4 antibodies bind PF4, forming immune complexes which activate platelets, monocytes and granulocytes, resulting in the VITT's immunothrombosis. The reason why only a tiny minority of patents receiving AdV-based COVID-19 vaccines develop VITT is still unknown. It has been hypothesized that individual intrinsic factors, either acquired (i.e., pre-priming of B cells to produce anti-PF4 antibodies by previous contacts with bacteria or viruses) or inherited (i.e., differences in platelet T-cell ubiquitin ligand-2 [TULA-2] expression) can predispose a few subjects to develop VITT. A better knowledge of the mechanistic basis of VITT is essential to improve the safety and the effectiveness of future vaccines and gene therapies using adenovirus vectors.

The Roles and Challenges of Advanced Therapies in the Management of Refractory Immune Thrombocytopenia: A Case Report and Review of the Literature.

The management of primary immune thrombocytopenia (ITP) is becoming a subject of interest as there appears to be treatment failure and resistance to modern conventional treatment, necessitating a more universal and goal-directed approach to management. Our patient is a 74-year-old male who was diagnosed with ITP six years ago and recently presented to the emergency department (ED) with complaints of melena stools and severe fatigue lasting for two days. Prior to the ED presentation, he had received multiple lines of treatment including splenectomy. On admission, the pathology after splenectomy showed a benign enlarged spleen with a focal area of intraparenchymal hemorrhage/rupture and changes compatible with ITP. He was managed with multiple platelet transfusions, IV methyl prednisone succinate, rituximab, and romiplostim. His platelet counts improved to 47,000, and he was discharged home on oral steroids with outpatient hematology follow-up. However, in a few weeks, his condition deteriorated, and he presented with an increased platelet count and further multiple complaints. Romiplostim was discontinued, and he was continued on prednisone 20 mg daily, after which he improved, and his platelet count reduced to 273,000 on 20 mg prednisone. This case calls attention to the need to review the role of combination therapy in treating refractory ITP and the prevention of complications of thrombocytosis secondary to advanced therapy. Treatment needs to be more streamlined, focused, and goal-directed. Escalation and de-escalation of treatment should be synchronized to prevent adverse complications from overtreating or undertreating.

Severe immune thrombocytopenia that developed immediately after COVID-19 in a school-aged patient: A case report.

Immune thrombocytopenia (ITP) is an autoimmune disorder that is sometimes triggered by a preceding viral infection and is characterized by a transient or persistent decrease in the platelet (Plt) count. Herein, we report the first pediatric case of severe ITP that developed immediately after the diagnosis of coronavirus disease 2019 (COVID-19) in a school-aged girl. A previously healthy six-year-old girl was diagnosed with COVID-19 a day before experiencing a high fever, sore throat, and headache. She also presented with gingival hemorrhage, petechiae around both eyes and on the chest, and ecchymosis on her right leg. Based on the mucosal hemorrhage and a very low Plt count of 3 × 103/µl, we diagnosed her with severe ITP and urgently treated her with intravenous immunoglobulin (IVIG) to prevent life-threatening hemorrhage. The Plt count increased to 266 × 103/µl one week after treatment with IVIG. Given the possibility of severe ITP secondary to COVID-19, patients with COVID-19 should be carefully examined for the signs of ITP, such as mucosal hemorrhage. Their Plt counts should also be monitored.

Current Concepts in the Diagnosis and Management of Adult Primary Immune Thrombocytopenia: Our Personal View.

Primary immune thrombocytopenia (ITP) is an acquired blood disorder that causes a reduction in circulating platelets with the potential for bleeding. The incidence of ITP is slightly higher in adults and affects more women than men until 60 years, when males are more affected. Despite advances in basic science, primary ITP remains a diagnosis of exclusion. The disease is heterogeneous in its clinical behavior and response to treatment. This reflects the complex underlying pathophysiology, which remains ill-understood. Platelet destruction plays a role in thrombocytopenia, but underproduction is also a major contributing factor. Active ITP is a proinflammatory autoimmune disease involving abnormalities within the T and B regulatory cell compartments, along with several other immunological abnormalities. Over the last several years, there has been a shift from using immunosuppressive therapies for ITP towards approved treatments, such as thrombopoietin receptor agonists. The recent COVID-19 pandemic has hastened this management shift, with thrombopoietin receptor agonists becoming the predominant second-line treatment. A greater understanding of the underlying mechanisms has led to the development of several targeted therapies, some of which have been approved, with others still undergoing clinical development. Here we outline our view of the disease, including our opinion about the major diagnostic and therapeutic challenges. We also discuss our management of adult ITP and our placement of the various available therapies.

A Case of COVID-19-Induced Immune Thrombocytopenia (ITP) in an Adult Female: An Under-Recognized Emerging Phenomenon.

Coronavirus disease 2019 (COVID-19) follows a mild course in majority of cases, but some patients may develop non-pulmonary yet life-threatening complications. A Pandora's box had been opened when multisystem hyper-inflammatory syndromes and autoimmune diseases that had been described previously in children and young adults, that are associated with COVID-19, have now emerged in adults. They need to be recognized as important sequelae of severe COVID-19 disease. Immune thrombocytopenia (ITP) or thrombocytopenic purpura is an autoantibody and T-cell-mediated autoimmune disorder characterized by isolated thrombocytopenia, which can be triggered by different infections. First-line treatment of severe ITP includes platelet transfusions in life-threatening cases, followed by corticosteroids and intravenous immunoglobulins (IVIG). Since the beginning of the pandemic, more and more cases of COVID-19-associated ITP have been reported. We report a case of acquired ITP in a young woman that could only be attributed to her COVID-19 infection and was refractory to platelet transfusion, requiring further treatments. The aim of this report is to review some of the etiologies and purposed molecular mechanisms of the autoimmune nature of the disease and to focus on diagnosis and treatment. We will review the current literature surrounding this non-pulmonary manifestation of COVID-19 and current treatment options for this uncommon presentation of ITP.

Autoimmune Diseases Affecting Hemostasis: A Narrative Review.

Hemostasis reflects a homeostatic mechanism that aims to balance out pro-coagulant and anti-coagulant forces to maintain blood flow within the circulation. Simplistically, a relative excess of procoagulant forces can lead to thrombosis, and a relative excess of anticoagulant forces can lead to bleeding. There are a wide variety of congenital disorders associated with bleeding or thrombosis. In addition, there exist a vast array of autoimmune diseases that can also lead to either bleeding or thrombosis. For example, autoantibodies generated against clotting factors can lead to bleeding, of which acquired hemophilia A is the most common. As another example, autoimmune-mediated antibodies against phospholipids can generate a prothrombotic milieu in a condition known as antiphospholipid (antibody) syndrome (APS). Moreover, there exist various autoimmunity promoting environments that can lead to a variety of antibodies that affect hemostasis. Coronavirus disease 2019 (COVID-19) represents perhaps the contemporary example of such a state, with potential development of a kaleidoscope of such antibodies that primarily drive thrombosis, but may also lead to bleeding on rarer occasions. We provide here a narrative review to discuss the interaction between various autoimmune diseases and hemostasis.

Microorganisms in the Pathogenesis and Management of Immune Thrombocytopenia (ITP)

Immune thrombocytopenia (ITP) represents an immune-mediated condition characterized by isolated thrombocytopenia due to the production of autoantibodies directed at human thrombocytes with a subsequent decrease in the platelet count below 100, 000 platelets/mmc. Microbial pathogens have emerged as key players in the development of ITP and are frequently listed as causes in the development of secondary ITP in adults, alongside autoimmune disorders, immune deficits, blood cancers, and others. This chapter briefly reviews the role of Helicobacter pylori, HIV, HCV, HBV, and SARS-CoV-2 (the viral agent responsible for the development of COVID-19) in the pathogenesis and management of ITP. In addition, the role of the gut microbiota and post-vaccination ITP is discussed. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.

Thrombocytopenia in the Course of COVID-19 Infection.

We report three cases of severe thrombocytopenia during COVID-19 infection associated with either cutaneous purpura or mucosal bleeding. The initial investigations ruled out other causes of thrombocytopenia. Two of the patients were treated with intravenous immunoglobulins and eltrombopag, while the third recovered spontaneously. A good clinical and biological response was achieved in all patients leading to hospital discharge. LEARNING POINTS: Immune thrombocytopenia should be considered in COVID-19-infected patients presenting with thrombocytopenia.Coronavirus-related thrombocytopenia can be severe and life-threatening.Despite the severity of coronavirus-related immune thrombocytopenia, recovery may be spontaneous or achieved following immunoglobulin or platelet growth factor administration.

Concurrence of immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura: a case report and review of the literature.

BACKGROUND: Immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura are both causes of thrombocytopenia. Recognizing thrombotic thrombocytopenic purpura is crucial for subsequent treatment and prognosis. In clinical practice, corticosteroids and rituximab can be used to treat both immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura; plasma exchange therapy is the first-line treatment in thrombotic thrombocytopenic purpura, while corticosteroids are strongly recommended as first-line treatment in immune thrombocytopenic purpura. The differential diagnosis of immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura is essential in clinical practice. However, case reports have suggested that immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura can occur concurrently. CASE PRESENTATION: We report the case of a 32-year-old Asian female without previous disease who presented with pancytopenia, concurrent with immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura. The morphology of the megakaryocytes in the bone marrow indicated immune-mediated thrombocytopenia. The patient received glucocorticoid treatment, and her platelet count increased; however, schistocytes remained high during the course of the therapy. Further investigations revealed ADAMTS13 activity deficiency and positive ADAMTS13 antibodies. The high titer of antinuclear antibody and positive anti-U1-ribonucleoprotein/Smith antibody indicated a potential autoimmune disease. However, the patient did not fulfill the current criteria for systemic lupus erythematosus or mixed connective tissue disease. The patient responded well to plasma exchange therapy, and her platelet count remained normal on further follow-up. CONCLUSIONS: Concurrence of immune thrombocytopenic purpura and thrombotic thrombocytopenic purpura is rare, but clinicians should be aware of this entity to ensure prompt medical intervention. Most of the reported cases involve young women. Human immunodeficiency virus infection, pregnancy, and autoimmune disease are the most common underlying conditions.

An Unusual Case of Combined Thrombosis and Amegakaryocytopenia Resembling Thrombosis With Thrombocytopenia Syndrome Following COVID-19 Infection in an Unvaccinated Patient.

As a global community, we have learned that the manifestations of severe acute respiratory syndrome coronavirus 2 (SAR-CoV-2), infection, or coronavirus disease 2019 (COVID-19), extends far beyond respiratory compromise. Thrombocytopenia is thought to occur secondary to increased platelet consumption. Platelet activation and platelet-mediated immune inflammation contribute towards the thromboembolic complications seen in COVID-19 patients. In this report, the authors present the unusual case of a 75-year-old female with a history of COVID-19 infection who presented with a transient ischemic attack, thrombocytopenia, and amegakaryocytopenia.

Recommendations on the Management of Patients with Immune Thrombocytopenia (ITP) in the Context of SARS-CoV-2 Infection and Vaccination: Consensus Guidelines from a Spanish ITP Expert Group.

Primary immune thrombocytopenia (ITP) is an acquired autoimmune disease with highly variable presentation, characteristics, and clinical course. Thrombocytopenia is a common complication of many viral infections, including SARS-CoV-2. In addition, both de novo ITP and exacerbation of ITP after vaccination against SARS-CoV-2 have been reported. Patients infected with SARS-CoV-2 develop a prothrombotic coagulopathy called COVID-19-associated coagulopathy (CAC). In addition, autoimmune hematological disorders secondary to SARS-CoV-2 infection, mainly ITP and autoimmune hemolytic anemia (AIHA), have been described. Furthermore, SARS-CoV-2 infection has been associated with exacerbation of autoimmune processes, including ITP. In fact, there is evidence of a high relapse rate in patients with preexisting ITP and COVID-19. As for vaccination against SARS-CoV-2, hematological adverse events (HAE) are practically anecdotal. The most common HAE is thrombocytopenia-associated thrombosis syndrome (TTS) linked to vectored virus vaccines. Other HAEs are very rare, but should be considered in patients with previous complement activation disease or autoimmunity. In patients with ITP who are vaccinated against SARS-CoV-2, the main complication is exacerbation of ITP and the bleeding that may result. In fact, this complication occurs in 12% of patients, with splenectomized and refractory patients with more than five lines of previous treatment and platelet counts below 50 × 109/L being the most vulnerable. We conclude that, in general, there is no greater risk of severe SARS-CoV-2 infection in ITP patients than in the general population. Furthermore, no changes are advised in patients with stable ITP, the use of immunosuppressants is discouraged unless there is no other therapeutic option, and patients with ITP are not contraindicated for vaccination against COVID-19.