Epistaxis and gross haematuria with severe thrombocytopaenia associated with influenza vaccination

Association Between Influenza Vaccine and Immune Thrombocytopenia: A Systematic Review and Meta-Analysis

BACKGROUND

Immune thrombocytopenia (ITP) is an uncommon but serious adverse reaction after vaccination. However, its association with vaccines other than the measles-mumps-rubella vaccine remains debatable. This study aimed to analyze ITP cases following influenza vaccination and assess any potential association.

METHODS

We performed a systematic search of the Web of Science, Embase, and PubMed databases from their inception to 15 April 2024. Cases were characterized qualitatively, and relative risk was assessed using either fixed or random models.

RESULTS

A total of 24 studies were analyzed, including 16 patients from 14 case reports. Patients averaged 56.7 years old, half were female, and ten patients had a history of prior illness. The mean time between vaccination and diagnosis was 13.3 days. Treatment primarily involved corticosteroids or intravenous immunoglobulin, with most recovering within a month. The pooled odds ratio for ITP post-influenza vaccination was 0.94 (95%CI: 0.85-1.03). Subgroup analyses conducted according to the study design and vaccine type did not reveal any significant results.

CONCLUSION

No evidence of an association between influenza vaccination and ITP was found. Further observational studies are required to verify this relationship.

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.

Acute Immune Thrombocytopenia Following Influenza Vaccination in a Patient With Untreated Helicobacter pylori Infection

A 70-year-old man with previously normal comprehensive blood counts (CBCs) was referred to our hospital for acute thrombocytopenia. Following a negative workup for secondary causes, we diagnosed immune thrombocytopenia (ITP). Aside from the influenza vaccine administered six days before presentation, there was no discernable precipitant on history. His only risk factor for ITP was untreated Helicobacter ​​​​​​pylori diagnosed over two months prior. With treatment, the patient's platelets normalized within three days. ITP following influenza vaccination has been documented in the literature and reported to regulatory bodies. Our case indicates that individuals with untreated H. pylori infection might be particularly vulnerable to such occurrences.

Thrombocytopenia in Virus Infections

Thrombocytopenia, which signifies a low platelet count usually below 150 × 10⁹/L, is a common finding following or during many viral infections. In clinical medicine, mild thrombocytopenia, combined with lymphopenia in a patient with signs and symptoms of an infectious disease, raises the suspicion of a viral infection. This phenomenon is classically attributed to platelet consumption due to inflammation-induced coagulation, sequestration from the circulation by phagocytosis and hypersplenism, and impaired platelet production due to defective megakaryopoiesis or cytokine-induced myelosuppression. All these mechanisms, while plausible and supported by substantial evidence, regard platelets as passive bystanders during viral infection. However, platelets are increasingly recognized as active players in the (antiviral) immune response and have been shown to interact with cells of the innate and adaptive immune system as well as directly with viruses. These findings can be of interest both for understanding the pathogenesis of viral infectious diseases and predicting outcome. In this review, we will summarize and discuss the literature currently available on various mechanisms within the relationship between thrombocytopenia and virus infections.

Risk Factors and Psychological Analysis of Chronic Immune Thrombocytopenia in Children

OBJECTIVE

To study the risk factors and psychological changes in children with chronic immune thrombocytopenia (CITP).

METHODS

This was a retrospective analysis of 234 children with ITP diagnosed and treated in the Affiliated Hospital of Southwest Medical University from January 2016 to December 2018. The clinical characteristics and related laboratory factors of all patients were collected, and their impact on the chronicity of ITP was analyzed. The Eysenck Personality Questionnaire-Children's Version (7-15 years old) is a psychological assessment of children with chronic ITP (CITP).

RESULTS

Univariate analysis found that the course of the initial diagnosis (χ2 =6.879, P<0.05), the age of onset (χ2 =13.846, P<0.05) and the absolute value of the initial diagnosis of peripheral blood lymphocytes (χ2 =6.436, P<0.05) had statistical differences in the chronicity of ITP in children; a multivariate analysis of the course of the first diagnosis, the age of onset and absolute lymphocyte count (ALC) revealed that ALC is an independent factor in children's chronic ITP (P<0.05). Compared with normal children, children with CITP had statistical significance in extraversion (t=-3.476, P<0.05); compared with newly diagnosed children, they had statistical significance in extraversion (E) and lying (L) (P<0.05); and there was no statistical difference compared with persistent children (P>0.05).

CONCLUSION

The age of onset, the absolute value of lymphocytes at the initial diagnosis, and the course of the initial diagnosis are important for predicting the chronicity of ITP in children. ALC is an independent predictor; children with chronic ITP have psychological problems.