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. 2021 Dec:9:100122.
doi: 10.1016/j.jvacx.2021.100122. Epub 2021 Nov 3.

Appendicitis as a possible safety signal for the COVID-19 vaccines

Joseph Mitchell  1 , Qun-Ying Yue  1
Affiliations

Appendicitis as a possible safety signal for the COVID-19 vaccines

Joseph Mitchell et al. Vaccine X. 2021 Dec.

Abstract

This study reviewed cases of appendicitis following administration of COVID-19 vaccines reported to VigiBase, the WHO database of individual case safety reports (ICSRs). Three hundred fifty-eight cases were identified, and disproportionate reporting was noted, with 329 calculated expected cases. Upon review, 24 ICSRs were excluded, so 334 unique ICSRs underwent clinical review from 19 countries. Forty-eight percent of ICSRs reported imaging and 69% noted surgical intervention. The cases were clinically coherent, with an apparent increase in reporting in the four days post-vaccination and a possible dose-response relationship. Appendicitis has been suggested as an adverse event of special interest post-vaccination against COVID-19 after a numerical increase in the vaccine arm of a clinical trial. The case series may be affected by differences in global patterns of reporting, and it is not possible to prove nor disprove causality from this case series. Global longitudinal studies are required to clarify any possible relationship.

Keywords: Appendicitis; COVID-19 vaccine; Pharmacovigilance; Safety signal.

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Conflict of interest statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Figures

Fig. 1
Fig. 1
Time to onset of appendicitis following COVID-19 vaccination, by vaccine manufacturer.
See this image and copyright information in PMC

References

    1. Anderson J.E., Campbell J.A., Durowoju L., Greenberg S.L.M., Rice-Townsend S.E., Gow K.W., et al. COVID-19-associated multisystem inflammatory syndrome in children (MIS-C) presenting as appendicitis with shock. J Pediatr Surg Case Rep. 2021;71:101913. doi: 10.1016/j.epsc.2021.101913. - DOI - PMC - PubMed
    1. Ansari P. Appendicitis [WWW Document], 2020. URL https://www.merckmanuals.com/professional/gastrointestinal-disorders/acu... (accessed 3.19.21).
    1. Bos R., Rutten L., van der Lubbe J.E.M., Bakkers M.J.G., Hardenberg G., Wegmann F., et al. Ad26 vector-based COVID-19 vaccine encoding a prefusion-stabilized SARS-CoV-2 Spike immunogen induces potent humoral and cellular immune responses. npj Vaccines. 2020;5(1) doi: 10.1038/s41541-020-00243-x. - DOI - PMC - PubMed
    1. Chae M., Kumar S., Cheema M. Mantle cell lymphoma presenting as acute appendicitis. Int J Surg Case Rep. 2015;6c:33–35. doi: 10.1016/j.ijscr.2014.10.068. - DOI - PMC - PubMed
    1. Corbett K.S., Flynn B., Foulds K.E., Francica J.R., Boyoglu-Barnum S., Werner A.P., et al. Evaluation of the mRNA-1273 Vaccine against SARS-CoV-2 in Nonhuman Primates. N Engl J Med. 2020;383(16):1544–1555. doi: 10.1056/NEJMoa2024671. - DOI - PMC - PubMed

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