A case of immune thrombocytopenic purpura after influenza vaccination: consequence or coincidence?

Immune thrombocytopenic purpura after influenza vaccine administration; a systematic review and meta-analysis

BACKGROUND

The American Society of Haematology defines immune thrombocytopenic purpura (ITP) as a common hematologic disorder characterized by a transient or long-term decrease in platelet counts (< 100 × 109/L.), purpura, and haemorrhagic episodes caused by antiplatelet autoantibodies, with the exclusion of other clinical conditions. We aimed to systematically determine the incidence of ITP in adults and children following influenza vaccination, the duration between vaccination and the occurrence of ITP, and to identify predictors of ITP after the vaccine.

METHODS

We searched PubMed, Cochrane Library, Google Scholar, Web of Science, Scopus, and Science Direct. We included primary studies that assessed the occurrence of immune thrombocytopenia in individuals who had received any influenza vaccine (primary or booster dose), regardless of the dosage, preparation, time of administration, or age of the participants. We excluded studies that were (a) Narrative, scoping, and umbrella reviews ;(b) studies with no accessible full text, abstract-only studies, or (c) Overlapping or unreliable data. The risk of bias in the included studies was assessed using the Joanna Briggs Institute (JBI) tool. We categorized studies for qualitative analysis based on study design. Descriptive statistics were used to summarize quantitative data, including the incidence of ITP after influenza vaccination.

RESULTS

Out of 729 articles retrieved from the database search, we included 24 studies. All patients identified and included in this systematic review presented with immune thrombocytopenia, determined by their platelet count. The period between vaccination and the occurrence of ITP ranged from (2:35 days). The mean duration was 13.5 days. The analysis revealed a statistically significant incidence rate ratio (IRR) = 1.85,95% CI [1.03-3.32] of ITP occurrence after 42 days.

CONCLUSIONS

Influenza-associated ITP is uncommon, self-limiting, non-life-threatening, and curable. None of the patients reported having severe adverse events or death. Further studies are required to confirm the exact incidence of the ITP to better understand the pathophysiology of ITP development post-influenza vaccination.

Is Childhood Immune Thrombocytopenia Associated With Acquired Toxoplasmosis? An Unusual Case of Infection That Led to Acute ITP in a Greek Male Toddler and Implications for Guidelines

INTRODUCTION

Childhood immune thrombocytopenic purpura (ITP) is a heterogeneous immune-mediated process triggered by infections, vaccines, allergies and parasites. Currently, there is little evidence in the literature beyond case reports of an association with Toxoplasma gondii (T. gondii).

METHODS

The authors describe the unusual case of an earlier healthy 2.5-year-old Greek boy who developed acute ITP with a life-threatening platelet count a few days after a T. gondii infection. Evidence for the infection onset was found incidentally 3 months after the initial admission to the hospital and only after any other plausible cause of thrombocytopenia was excluded, according to diagnosis guidelines.

RESULTS

The boy underwent 3 intravenous immunoglobulin treatments within a trimester, a period during which his alarming platelets count levels led to housebound activities. A quite slow recovery was only ignited after the third treatment, which was administered in conjunction with a mild antibiotic medication for the T. gondii infection. Full recovery was obtained 9 months after the initial admission, although the boy's potential scored high in clinical prediction models for developing transient ITP.

CONCLUSION

There is a need for more research on ITPs with no obvious cause to investigate a causal association with toxoplasmosis. Currently, testing for diseases of greater rarity and of higher diagnostic cost than T. gondii is included in the ITP guidelines. Hence, routinely testing for toxoplasmosis when considering potential childhood ITP triggers and infection treatment complementary to treating the ITP might be the key to accelerating the healing process and improving the quality of life of otherwise confined children.

The Frequency and Patterns of Post-COVID-19 Vaccination Syndrome Reveal Initially Mild and Potentially Immunocytopenic Signs in Primarily Young Saudi Women

Vaccination is the most promising approach for ending or containing the SARS-CoV-2 pandemic. However, serious post-COVID-19 vaccine reactions, including immunocytopenia (ITP) syndrome, have been increasingly reported. Several factors cause increased risks including multiple doses, age-dependent heterogeneity in immune-responses, platelet cross-reactions with microbial components, and Long-COVID syndrome. Thus, in the absence of widely available specific therapeutics, vigilance is important while more studies are needed. Using a structured questionnaire sent to different regions in Saudi Arabia, we conducted a comprehensive investigation on the frequency, rates, disease patterns, and patient demographics of post-COVID-19 vaccine side effects on febrile patients after administration three major vaccines. Results indicated that the majority of respondents administered Pfizer BioNtech vaccine (81%, n = 809); followed by AstraZeneca (16%, n = 155); and Moderna (3%, n = 34). Overall 998 participants, 74% (n = 737) showed no serious symptoms; however, 26.2% (n = 261) revealed typical syndromes. In a focused group of 722 participants, the following rates were identified: shortness of breath (20%), bruises or bleeding (18%), inattention (18%), GIT symptoms (17.6%), skin irritation (8.6%), and anosmia and ageusia (8%) were the most prominent among those who showed typical symptoms. The onset time was mostly between 1–3 days in 49% (n = 128), followed by 4–7 days in 21.8% (n = 57), 8–14 days in 16.5% (n = 43), and more than a month in 12.6% (n = 33). The onsets occurred mostly after the first, second, or both doses, 9%, 10%, and 7% of participants, respectively. The frequency of symptoms was significantly higher after Moderna® vaccine (p-value = 0.00006) and it was significantly lower in participants who received Pfizer (p-value = 0.00231). We did not find significant difference in symptoms related to differences in regions. Similarly, the region, age, sex, education, and nationality had no influence on the dose and onset timings. The findings of this study have significant clinical implications in disease management strategies, preventive measures, and vaccine development. Future vertical studies would reveal more insights into the mechanisms of post-COVID-19 vaccine syndrome.

Severe Immune Thrombocytopenia after COVID-19 Vaccination: Two Case Reports and a Literature Review

We herein report two cases of coronavirus disease 2019 (COVID-19) vaccine-induced immune thrombocytopenia (ITP). A 69-year-old Japanese man developed severe thrombocytopenia after COVID-19 vaccination. He had oral bleeding and hemoptysis but no thrombotic symptoms. He improved rapidly with oral prednisolone therapy. A 34-year-old Japanese woman had generalized purpura after COVID-19 vaccination. Her platelet count improved rapidly after treatment with prednisolone and eltrombopag. The occurrence of two cases of ITP after COVID-19 vaccination at a single institution suggests that there could be more such undiagnosed cases, especially cases of mild secondary ITP.

Severe Immune Thrombocytopenic Purpura Following Influenza Vaccination: A Case Report

Immune thrombocytopenia (ITP) is a rare, acquired bleeding disorder caused by various underlying etiologies. ITP can be triggered by medication, infections, cancers, and autoimmune diseases. One of the rare triggers is vaccination. As in many cases, the symptoms are mild and the cause is idiopathic, and it may not be diagnosed without extensive investigations. It can also be difficult to differentiate between medication-induced thrombocytopenia and ITP, particularly in older patients with multiple comorbidities and receiving multiple medications. Here, we describe an older patient with acute onset ITP following influenza vaccination. An 88-year-old man presented with complaints of systemic itchiness and bleeding from his mouth. Four days prior to the symptoms appearing, he had received an influenza vaccine and did not experience any severe pain or anaphylactic symptoms. On presentation, he had multiple bleeding blisters and systemic petechiae. Blood tests revealed a platelet count of 1000/µL. A month prior, his platelet count was 1.5×105/µL. The blood culture results were negative and a bone marrow biopsy revealed multiple megakaryocytes, without blastocytes or evidence of hemophagocytosis. The patient was diagnosed with influenza vaccine-induced severe ITP and was treated with intravenous high-dose prednisolone. Although vaccine-related ITP is rare, in patients with systemic symptoms, primary care physicians should perform systematic physical examinations to detect any hemorrhage, as ITP is a possibility.

Vigilance regarding immune thrombocytopenic purpura after COVID-19 vaccine

INTRODUCTION

Based on the severity of thrombocytopenia, patients with immune thrombocytopenic purpura (ITP) are at an increased risk of mucocutaneous or major bleeding.

DISCUSSION

There has been an increased risk of ITP after administration of various vaccines like influenza, measles-mumps-rubella, hepatitis B, and diphtheria-tetanus-pertussis. The pathogenesis of vaccine-related thrombocytopenia is not completely clear and is probably caused by molecular mimicry. Till date, there have been few reported cases of thrombocytopenia in the pharmacovigilance databases after patients received the Pfizer and Moderna coronavirus disease-19 (COVID-19) vaccines.

CONCLUSION

Emergency physicians should be aware of the occurrence of vaccine-induced ITP in patients who present with bleeding manifestations, especially after the current boost in COVID-19 vaccination drive worldwide.

From influenza infection to anti-ADAMTS13 autoantibodies via cross-reactivity

Autoantibodies (AAbs) against von Willebrand factor (vWF)-cleaving protease ADAMTS13 causally relate to thrombotic thrombocytopenic purpura (TTP). How anti-ADAMTS13 AAbs are generated is unknown. Starting from reports according to which influenza infection can trigger TTP by the production of ADAMTS13 AAbs, this study explores influenza viruses and ADAMTS13 protein for common peptide sequences that might underlie anti-influenza immune responses able to cross-react with ADAMTS13. Results document that numerous peptides are shared between influenza A and B viruses and ADAMTS13, thus supporting the hypothesis of cross-reactivity as a mechanism driving the generation of anti-ADAMTS13 AAbs.

Observational safety study of specific outcomes after trivalent cell culture seasonal influenza vaccination (Optaflu® ) among adults in THIN database of electronic UK primary healthcare records

PURPOSE

To investigate the safety of trivalent seasonal influenza vaccine (TIVc) (Optaflu^® ), the first cell culture seasonal trivalent influenza vaccine available in Europe.

METHODS

Codes and unstructured text in adult electronic healthcare records (The Health Improvement Network) were searched for a TIVc brand name or batch number and possible outcomes within a 3 month pre- to 6 month post-TIVc exposure study period (2012-2015). The outcomes were severe allergic reactions, Bell's palsy, convulsions, demyelination, paresthesia, noninfectious encephalitis, neuritis (optic and brachial), vasculitis, inflammatory bowel disease, and thrombocytopenia. Risk periods were defined based on biologically plausible time frame postvaccination when an outcome caused by the vaccine might be expected to occur. Possible outcomes were adjudicated against outcome specific case definitions and a date of onset assigned by using electronic and other medical records. Observed (risk period) to expected (outside risk and preexposure periods) rate ratios, postexposure incidence, and plots of time from exposure to outcome were reported.

RESULTS

Sixteen of 1011 events from 4578 exposures fulfilled a primary case definition and had a date of onset during the study period. Three were in observed time. The observed-to-expected rate ratios were (3.3, 95% CI 0.3, 31.7) for convulsions and (1.5, 95% CI 0.2, 14.9) for thrombocytopenia with 1 outcome each in observed time. There was 1 incident inflammatory bowel disease in observed, but none in expected, time.

CONCLUSION

The small sample size restricts interpretation; however, no hypothesis of an increased risk of a study outcome was generated. Adjudication of events against case definitions to reduce misclassification of onset and outcomes allowed use of precise risk periods. KEY POINTS This observational study did not generate a hypothesis of an association between the first cell-culture seasonal influenza vaccination available in the European Union and any of the study outcomes (severe allergic reactions, Bell's palsy, convulsions, demyelination, paresthesia, noninfectious encephalitis, neuritis [optic and brachial], vasculitis, inflammatory bowel disease [IBD], and thrombocytopenia). The small sample size limits interpretation of the results. The review of each possible outcome identified from electronic healthcare records against case definitions was included to minimize misclassification of time and outcomes and allow the use of precise risk-periods in an observed-to-expected within cohort analysis. Plots of time from exposure to outcome were included to assess the risk windows.

Recurrent Immune Thrombocytopenia After Influenza Vaccination: A Case Report

Immune thrombocytopenia (ITP) is an isolated autoimmune condition, often preceded by a viral infection. Vaccines, mainly the measles-mumps-rubella vaccine, have also been associated with an increased risk of developing the disease. Although some case reports of ITP after influenza immunization in adults have been published, epidemiologic studies examining the role of the influenza vaccine as a trigger of ITP have not conclusively proven causality. We report a child with 3 occurrences of ITP, each within 1 week of receiving the influenza trivalent inactivated vaccine. He recovered fully in-between the episodes, and no further episodes have occurred since discontinuation of seasonal influenza vaccination. To the best of our knowledge, this report is the first showing, with high probability, the influenza vaccine as a cause for ITP in a pediatric patient.

The safety of influenza vaccines in children: An Institute for Vaccine Safety white paper

Most influenza vaccines are generally safe, but influenza vaccines can cause rare serious adverse events. Some adverse events, such as fever and febrile seizures, are more common in children than adults. There can be differences in the safety of vaccines in different populations due to underlying differences in genetic predisposition to the adverse event. Live attenuated vaccines have not been studied adequately in children under 2 years of age to determine the risks of adverse events; more studies are needed to address this and several other priority safety issues with all influenza vaccines in children. All vaccines intended for use in children require safety testing in the target age group, especially in young children. Safety of one influenza vaccine in children should not be extrapolated to assumed safety of all influenza vaccines in children. The low rates of adverse events from influenza vaccines should not be a deterrent to the use of influenza vaccines because of the overwhelming evidence of the burden of disease due to influenza in children.

Postinfluenza Vaccination Idiopathic Thrombocytopenic Purpura in Three Elderly Patients

The etiologies of secondary idiopathic thrombocytopenic purpura (ITP) include infection, autoimmune disease, and immunodeficiency. We report the cases of three elderly patients who developed ITP after receiving influenza vaccinations. The platelet count of an 81-year-old woman fell to 27,000/μL after she received an influenza vaccination. A 75-year-old woman developed thrombocytopenia (5,000 platelets/μL) after receiving an influenza vaccination. An 87-year-old woman whose laboratory test values included a platelet count of 2,000/μL experienced genital bleeding after receiving an influenza vaccination. After Helicobacter pylori (HP) eradication or corticosteroid treatment, all of the patients' platelet counts increased. Influenza vaccination is an underlying etiology of ITP in elderly patients. HP eradication or corticosteroid treatment is effective for these patients. Clinicians should be aware of the association between ITP and influenza vaccinations.

Immune thrombocytopenic purpura (ITP) associated with vaccinations: a review of reported cases

Immune thrombocytopenic purpura (ITP) is an autoimmune condition characterized by low platelet count with mucocutaneous and other bleedings. Clinical manifestations may range from spontaneous formation of purpura and petechiae, especially on the extremities, to epistaxis, bleeding at the gums or menorrhagia, any of which occur usually if the platelet count is below 20,000 per μl. A very low count may result in the spontaneous formation of hematomas in the mouth or on other mucous membranes. Fatal complications, including subarachnoid or intracerebral, lower gastrointestinal or other internal bleeding can arise due to an extremely low count. Vaccines may induce ITP by several mechanisms. Vaccine-associated autoimmunity may stem not only from the antigen-mediated responses but also from other constituents of the vaccine, such as yeast proteins, adjuvants, and preservatives diluents. The most likely is through virally induced molecular mimicry. The binding of pathogenic autoantibodies to platelet and megakaryocytes may cause thrombocytopenia by different mechanisms, such as opsonization, direct activation of complement, or apoptotic pathways. The autoantibodies hypothesis is not sufficient to explain all ITP cases: In the anti-platelet antibody-negative cases, a complementary mechanism based on T cell immune-mediated mechanism has been suggested. In particular, T cell subsets seem dysregulated with an increased production of pro-inflammatory cytokines, as IFN-γ and TNF, and chemokines, as CXCL10. Vaccines are one of the most striking discoveries in human history that changed dramatically life expectancy. Nonetheless, the occurrence of adverse events and autoimmune phenomena has been described following vaccination, and ITP may represent one of this.

Autoimmune disorders and quadrivalent human papillomavirus vaccination of young female subjects

OBJECTIVES

The aim of this study was to investigate whether the quadrivalent human papillomavirus (HPV) vaccine Gardasil is associated with a change in the risk of autoimmune disorders (ADs) in young female subjects.

DESIGN

Systematic case-control study of incident ADs associated with quadrivalent HPV vaccination in young women across France.

PARTICIPANTS AND SETTING

A total of 113 specialised centres recruited (from December 2007 to April 2011) females aged 14-26 years with incident cases of six types of ADs: idiopathic thrombocytopenic purpura (ITP), central demyelination/multiple sclerosis (MS), Guillain-Barré syndrome, connective tissue disorders (systemic lupus erythematosus, rheumatoid arthritis/juvenile arthritis), type 1 diabetes mellitus and autoimmune thyroiditis. Control subjects matched to cases were recruited from general practice.

ANALYSIS

Multivariate conditional logistic regression analysis; factors included age, geographical origin, smoking, alcohol consumption, use of oral contraceptive(s) or vaccine(s) other than Gardasil received within 24 months before the index date and personal/family history of ADs.

RESULTS

Overall, 211 definite cases of ADs were matched to 875 controls. The adjusted odds ratio (OR) for any quadrivalent HPV vaccine use was 0.9 [95% confidence interval (CI) 0.5-1.5]. The individual ORs were 1.0 (95% CI 0.4-2.6) for ITP, 0.3 (95% CI 0.1-0.9) for MS, 0.8 (95% CI 0.3-2.4) for connective disorders and 1.2 (95% CI 0.4-3.6) for type 1 diabetes. No exposure to HPV vaccine was observed in cases with either Guillain-Barré syndrome or thyroiditis.

CONCLUSIONS

No evidence of an increase in the risk of the studied ADs was observable following vaccination with Gardasil within the time periods studied. There was insufficient statistical power to allow conclusions to be drawn regarding individual ADs.

Clinical practice: immune thrombocytopenia in paediatrics

Immune thrombocytopenia (ITP) is a disease affecting both children and adults. It is defined as acquired isolated thrombocytopenia caused by the autoimmune production of anti-platelet antibodies. Childhood ITP most frequently occurs in young children who have been previously well, although a viral respiratory tract infection often precedes thrombocytopenia. A benign and self-limiting course is common, but major bleeding complications such as intracranial haemorrhage may occur. Yet one cannot predict which child will have a prolonged course of thrombocytopenia and who will develop an intracranial haemorrhage. In children without atypical characteristics, only minimal diagnostic investigations are needed, and most paediatric ITP patients do not need platelet-enhancing therapy even though various treatment options are available. A "watch and wait" strategy should be considered in paediatric patients with mild disease. Steroids, intravenous immunoglobulin G or anti-D immunoglobulin are the current first-line therapeutic measures for children at risk for severe bleeding. When life-threatening bleeding occurs, a combination of therapies is needed. In this review, we summarise the current knowledge on primary ITP in children and adolescents.

Severe immune thrombocytopenia possibly elicited by the anti-influenza viral agent peramivir

A 44-year-old man whose platelet count had been at the lower limit of the normal range for years visited the urgent care department of our hospital for treatment of a high fever and severe fatigue. The influenza A virus was detected, and the patient therefore received the intravenous antiviral agent, peramivir. One week later, he developed systemic petechial rashes. A peripheral blood examination showed a markedly decreased platelet count (3.0×10(9) cells/L), and the bone marrow findings were compatible with a diagnosis of immune thrombocytopenia (ITP). Furthermore, a drug-induced lymphocyte-stimulating test was positive for peramivir. The thrombocytopenia slowly responded to treatment with oral prednisolone. This case suggests that neuraminidase inhibitors, including peramivir, can elicit or worsen ITP.

Vaccine administration and the development of immune thrombocytopenic purpura in children

The most important reasons cited by the opponents of vaccines are concerns about vaccine safety. Unlike issues such as autism for which no indisputable documentation of direct relationship with vaccine use is available, immune thrombocytopenic purpura (ITP) is an adverse event that can really follow vaccine administration, and may limit vaccine use because little is known about which vaccines it may follow, its real incidence and severity, the risk of chronic disease, or the possibility of recurrences after new doses of the same vaccine. The main aim of this review is to clarify the real importance of thrombocytopenia as an adverse event and discuss how it may interfere with recommended vaccination schedules. The available data clearly indicate that ITP is very rare and the only vaccine for which there is a demonstrated cause-effect relationship is the measles, mumps and rubella (MMR) vaccine that can occur in 1 to 3 children every 100,000 vaccine doses. However, also in this case, the incidence of ITP is significantly lower than that observed during the natural diseases that the vaccine prevents. Consequently, ITP cannot be considered a problem limiting vaccine use except in the case of children suffering from chronic ITP who have to receive MMR vaccine. In these subjects, the risk-benefit ratio of the vaccine should be weighed against the risk of measles in the community.

A case-control study to assess the risk of immune thrombocytopenia associated with vaccines

The cause of immune thrombocytopenia (ITP) remains unknown. Studies have suggested immunizations as possible triggering factors of ITP through molecular mimicry. This case-control study explored potential associations between adult ITP and various routinely administered vaccines. A network of internal medicine and hematology centers across France recruited 198 incident (ie, newly diagnosed) cases of ITP between April 2008 and June 2011. These cases were compared with 878 age- and sex-matched controls without ITP recruited in general practice. Information on vaccination was obtained from patients' standardized telephone interviews. Sixty-six of 198 cases (33.3%) and 303 of 878 controls (34.5%) received at least 1 vaccine within the 12 months before the index date. We found no evidence of an increase in ITP after vaccination in the previous 6 or 12 months (adjusted odds ratio [OR] for the previous 12 months = 1.0; 95% confidence interval, 0.7-1.4). When the 2-month time window was used, higher ORs were observed for all vaccines (OR = 1.3). This increase was mainly attributable to the vaccination against diphtheria-tetanus-pertussis-poliomyelitis (OR = 1.5) and was not statistically significant. The results of the present study show that in an adult population, the exposure to common vaccines is on average not associated with an observable risk of developing ITP.

A case of Evans' syndrome following influenza vaccine

BACKGROUND

Evans' syndrome is an uncommon condition defined by the combination (either simultaneously or sequentially) of immune thrombocytopenia purpura and autoimmune hemolytic anemia with a positive direct antiglobulin test in the absence of known underlying etiology.

OBJECTIVES

We present a case of Evans' syndrome following influenza vaccination.

CASE REPORT

A 50-year-old man with no prior medical history developed Evans' syndrome 4 days after receiving influenza immunization. The patient improved following treatment with oral prednisone and intravenous immunoglobulin.

CONCLUSION

Influenza vaccine is one of the most commonly used vaccines worldwide, with millions of people being vaccinated annually. Despite its wide use, only sparse information has been published concerning any hematological effects of this vaccine. The rarity of such effects supports the safety of using this vaccine.