Objectives: To study the relationship between coronavirus disease 2019 (COVID-19) vaccination and the risk of immune thrombocytopenia (ITP).
Methods: A retrospective analysis was conducted on children aged 3-17 years with newly diagnosed ITP who were hospitalized in Children's Hospital Affiliated to Zhengzhou University from November 2021 to December 2022. Clinical data and COVID-19 vaccination status were compared among three groups: ITP patients vaccinated within 12 weeks before onset, vaccinated more than 12 weeks before onset, and unvaccinated. Changes in serum immunoglobulin and complement levels were analyzed among five groups: ITP patients vaccinated <4 weeks before onset, 4-<8 weeks before onset, 8-<12 weeks before onset, ≥12 weeks before onset, and unvaccinated. A case-control design was used to estimate the risk of ITP: 387 children aged 3-17 years with fractures hospitalized during the same period in the emergency department of the hospital were selected as the control group, and the exposure to COVID-19 vaccination within 12, 8, and 4 weeks before onset in ITP children was compared to estimate the risk of ITP.
Results: Among 129 ITP children, there were no statistically significant differences in age, gender, rate of preceding infections, absolute platelet count at initial diagnosis, absolute lymphocyte count at initial diagnosis, bleeding score, positive anti-nuclear antibody rate, absolute platelet count after 4 days of treatment, recurrence rate, and proportion of patients with disease duration ≥3 months among the three groups vaccinated within 12 weeks before onset, vaccinated more than 12 weeks before onset, and unvaccinated (P>0.05). There was a statistically significant difference in serum immunoglobulin G, immunoglobulin A, and complement component 3 levels among the groups vaccinated <4 weeks, 4-<8 weeks, 8-<12 weeks, and ≥12 weeks before onset, and unvaccinated (P<0.05). The risk estimation results showed that COVID-19 vaccination within 12 weeks, 8 weeks, and 4 weeks before onset did not increase the risk of ITP (P>0.05).
Conclusions: COVID-19 vaccination does not increase the risk of ITP.
目的: 分析新型冠状病毒感染（coronavirus disease 2019, COVID-19）疫苗接种与免疫性血小板减少症（immune thrombocytopenia, ITP）发生风险的关系。方法: 回顾性分析郑州大学附属儿童医院2021年11月—2022年12月住院的3~17岁初诊ITP患儿COVID-19疫苗接种情况与临床资料。比较ITP患儿发病前12周内、12周前接种及未接种COVID-19疫苗3组患儿的临床资料；分析ITP发病前<4周、4~<8周、8~<12周、≥12周接种疫苗及未接种疫苗5组患儿血清免疫球蛋白和补体水平的变化。采用病例对照设计进行疾病发生风险估计：选取同时期该院急诊科住院的387例3~17岁骨折儿童作为对照组，与ITP患儿发病前12周、8周、4周疫苗暴露情况比较以估计ITP发生风险。结果: 129例ITP患儿中，发病前12周内、12周前接种及未接种COVID-19疫苗3组年龄、性别、前驱感染率、初诊血小板计数绝对值、初诊淋巴细胞计数绝对值、出血评分、抗核抗体阳性率、治疗4 d后血小板计数绝对值、复发率及病程持续≥3个月患儿比例等指标的比较差异均无统计学意义（P>0.05）。发病前<4周、4~<8周、8~<12周、≥12周接种及未接种疫苗患儿血清免疫球蛋白G、免疫球蛋白A、补体成分3水平的比较差异有统计学意义（P<0.05）。风险估计分析结果显示，发病前12周内、8周内及4周内COVID-19疫苗接种均不引起ITP发生风险增加（P>0.05）。结论: COVID-19疫苗接种不引起ITP发生风险增加。.
Keywords: Child; Coronavirus disease 2019; Immune thrombocytopenia; Immunoglobulin; Vaccination.