A man in his seventies with pleural effusion, knee pain and dysarthria following open heart surgery.

Background: Patients receiving immunosuppressive therapy are vulnerable to infections. The wide range of possible causative pathogens, often with unusual manifestations and/or confounding comorbidity, are challenging for diagnosis and treatment.

Case Presentation: An active man in his seventies developed recurrent pleural effusions, peripheral oedemas and fatigue, diagnosed as post-cardiotomy syndrome, within four months of open heart surgery and ablation due to aortic stenosis and atrial fibrillation. Following initial improvement on colchicine and corticosteroids, he deteriorated with respiratory symptoms, dysarthria and knee pain. Investigations revealed abscesses in brain and soft tissue with growth of Nocardia spp. Completion of the long-term broad-spectrum antibiotic treatment was challenging.

Interpretation: Systemic nocardiosis that developed in a patient on corticosteroid treatment, initiated to treat post-cardiotomy syndrome, highlights the risk of opportunistic infections by widely used drugs. The case also illustrates the importance of interdisciplinary collaboration for diagnosis and treatment.