Purulent pericarditis caused by methicillin-sensitive Staphylococcus aureus in an immunocompetent adult after COVID-19 pneumonia: a case report

BACKGROUND: SARS-CoV-2 has been implicated in many cardiac pathologies, manifesting mainly as acute. However, acute purulent pericarditis is exceedingly rare in the antibiotic era. Though, few studies have associated it with long-COVID, prompt recognition and treatment are crucial. CASE SUMMARY: A 61-year-old immunocompetent woman presented with a left lower limb pitting oedema 1 month after COVID-19 pneumonia. Following clinical, laboratory, and imaging work-up, the patient was found to have deep vein thrombosis of the anterior and posterior tibial and gastrocnemius veins. Owning to persistent sinus tachycardia, an additional work-up was performed, which revealed a large pericardial effusion. Pericardiocentesis drained the frank pus, and subsequently, empirical antibiotics therapy was initiated. Pericardial fluid cultures showed methicillin-sensitive Staphylococcus aureus (MSSA). Following the antibiotic treatment with cloxacillin 6 × 2 g IV for 6 weeks, the patient fully recovered. DISCUSSION: Herein, we report a rare case of bacterial pericarditis caused by MSSA 1 month after COVID-19 pneumonia. Additionally, this condition may arise as a result of immunosuppressive treatment with glucocorticoids during and after COVID-19 pneumonia. However, the causal association has not yet been confirmed.