Mycetoma Leading to Effusive Constrictive Pericarditis in an Immunocompetent Individual: A Rare Encounter

Nocardial infections are rare but serious, often leading to systemic and cardiopulmonary complications. This is the first reported case of <i>Nocardia beijingensis</i> causing constrictive pericarditis in an immunocompetent individual. We present a 37-year-old Caucasian female patient with no significant medical history who developed pericarditis symptoms after handling crates from China. Despite initial treatment for presumed viral pericarditis, her condition worsened. Further investigation identified <i>Nocardia beijingensis</i> as the cause of effusive constrictive pericarditis. The patient underwent a pericardiectomy, which resolved her symptoms. This case demonstrates the need to consider rare pathogens in cases of refractory pericarditis, regardless of the patient's immune status. Clinicians should maintain a high level of suspicion for uncommon infections in progressively worsening cases and adopt a multidisciplinary diagnostic approach for timely intervention.