Abstract
BACKGROUND: Granulicatella adiacens is an uncommon cause of infective endocarditis (IE) and has rarely been associated with mycotic pulmonary artery aneurysm (MPAA). CASE SUMMARY: An 18-year-old woman with patent ductus arteriosus and poor dental hygiene presented with massive hemoptysis. Multimodal imaging identified G. adiacens IE complicated by a saccular MPAA and severe valvular involvement. Management included targeted antibiotics, endovascular embolization, and combined mitral-aortic valve surgery with patent ductus arteriosus closure, resulting in full clinical recovery. DISCUSSION: A fastidious microbiological behavior can delay diagnosis, making multimodal imaging essential for detecting complications such as MPAA. Coordinated medical-surgical therapy is critical in complex IE presentations. TAKE-HOME MESSAGES: G. adiacens can cause aggressive IE with rare vascular complications. Multimodal imaging is indispensable for timely detection of MPAA in IE, enabling staged interventions that optimize outcomes.