Can chronic anti-tumour necrosing factor therapy and colic polyps overwhelm a normal functioning mitral valve? A case report of an endocarditis complicated by a ruptured intracranial mycotic aneurysm.

Immunosuppression from etanercept treatment was likely responsible for this unspecific clinical presentation and potentially devastating intracranial mycotic aneurysm. This complication is infrequently reported within 6 months of anti-tumour necrosing factor therapy initiation but occurred after more than 11 years of therapy in our patient. This case is a timely reminder of the clinical challenges of endocarditis in immunosuppressed patients and highlights a potential long-term complication of etanercept.