Eosinophilic Gastroenteritis Following Covid-19 MRNA Vaccination

Large-scale clinical studies for COVID-19 vaccines have shown the infection-preventing effect and short-term adverse effects. Some rare illnesses such as eosinophilia can develop following COVID-19 vaccinations.

We report a case of 65-year-old man with unexplained abdominal pain that developed 2 weeks after COVID-19 mRNA vaccination. The patient had received a second dose of COVID-19 mRNA vaccine and revealed eosinophilia at the first visit to our hospital. Eosinophil infiltration was observed in the lamina propria of the duodenum by a step biopsy. Montelukast 10 mg was administered as the initial treatment of eosinophilic gastroenteritis (EGE), and the abdominal pain was improved.

The strong influence of COVID-19 vaccination on the development of EGE remains unproven. Reports of eosinophilia following COVID-19 vaccination have discussed that COVID-19 mRNA vaccination triggered an eosinophilic response.

This case presented EGE that developed following COVID-19 mRNA vaccination, which would be a rare adverse event.

Eosinophilia can develop following COVID-19 mRNA vaccination.To evaluate the relationships of these illnesses with vaccination, clinicians should collect information on vaccinations history and vaccination dates through interviews.It is clinically practical to know the differential diseases that may develop after a new vaccination.