Delayed prosthetic seroma: a localized inflammatory response to COVID vaccination and infection?

We present a patient whom we believe developed a late abdominal mesh collection in response to COVID-19 mRNA vaccination booster and COVID-19 infection. A polypropylene mesh was placed during her right breast reconstruction operation 2 years ago where she underwent a right transverse abdominis rectus muscle (TRAM) free flap. She recovered uneventfully from this operation. This lady, though vaccinated, developed respiratory symptoms and tested positive for COVID-19 infection 3 days after her booster injection. She then noticed right-sided abdominal swelling 3 days after the onset of respiratory symptoms. She only presented 1 month later due to a 7-day history of pain at the site of abdominal swelling. A computed tomography scan confirmed the presence of a seroma, and she underwent ultrasound-guided percutaneous drainage. A COVID Antigen Rapid Test of the fluid returned positive, though the PCR swab returned negative. There have been no published reports of periprosthetic mesh seroma after COVID-19 vaccination or infection to date. We wanted to share our experience so that other surgeons may be aware of this potential presentation given the current ongoing pandemic. Level of evidence: Level V, risk/prognostic.