Lymphadenopathy post-COVID-19 vaccination with increased FDG uptake may be falsely attributed to oncological disorders: A systematic review.

Coronavirus disease 2019 (COVID-19) has caused a global pandemic that continues to cause numerous deaths to date. Four vaccines have been approved by the Food and Drug Administration as of July 2021 to prevent the transmission of COVID-19: Pfizer, Moderna, AstraZeneca, and Janssen. These vaccines have shown great efficacy and safety profile. One side effect that has been widely reported is post-COVID-19 vaccination lymphadenopathy. Due to the mimicry of the lymphadenopathy for metastases in some oncologic patients, there have been reports of patients who underwent biopsies that showed pathologic confirmation of benign reactive lymphadenopathy secondary to the COVID-19 vaccine. Therefore, understanding the incidence of lymphadenopathy post-COVID-19 vaccinations will help guide radiologists and oncologists in their management of patients, both present oncologic patients, and patients with concerns over their newly presenting lymphadenopathy. A systematic literature search was performed using several databases to identify relevant studies that reported lymphadenopathy post-COVID-19 vaccination. Our results revealed that several cases have been detected in patients undergoing follow-up fluorodeoxyglucose (FDG)-positron emission tomography-computerized tomography scans where lymph nodes ipsilateral to the vaccine injection site show increased uptake of FDG. Thus, knowledge of the incidence of lymphadenopathy may help avoid unnecessary biopsies, interventions, and changes in management for patients, especially oncologic patients who are at risk for malignancies.

Anaphylaxis and Related Events Following COVID-19 Vaccination: A Systematic Review.

The coronavirus disease 2019 (COVID-19), induced by the severe acute respiratory syndrome coronavirus 2, is responsible for a global pandemic following widespread transmission and death. Several vaccines have been developed to counter this public health crisis using both novel and conventional methods. Following approval based on promising efficacy and safety data, the AstraZeneca, Janssen, Moderna, Pfizer/BioNTech, and Sinovac vaccines have been administered globally among different populations with various reported side effects. Reports of life-threatening anaphylaxis following administration were of particular concern for both health care providers and the public. A systematic literature search using PubMed, Embase, Scopus, Web of Science, Science Direct, MedRxiv, and Lens.org databases identified relevant studies reporting anaphylaxis following vaccine administration. This systematic review includes 41 studies reporting anaphylaxis. A total of 7942 cases, including 43 deaths, were reported across 14 countries. Most cases occurred following the administration of the first dose. Importantly, the benefits of vaccination outweigh the risks of anaphylaxis. Subsequently, as populations continue to get vaccinated, it is important for health care providers to be able to recognize individuals at risk of developing anaphylaxis. Furthermore, they must be familiar with both the clinical hallmarks and treatment of anaphylactic reactions to minimize long-term sequalae and prevent death in vaccinated individuals.