A Case of Infective Endocarditis Following Bone Marrow Transplantation for Myelodysplastic Syndrome.

A 63-year-old man was diagnosed with myelodysplastic syndrome (MDS) at the age of 62 by the hematology department. The patient underwent four cycles of azacitidine (AZA) therapy, followed by successful bone marrow transplantation (BMT). Subsequently, he was hospitalized twice for graft-versus-host disease (GVHD). Prednisolone was initially administered at 60 mg and was gradually tapered to 10 mg/day. Additionally, the patient was prescribed 10 mg/day of a Janus kinase inhibitor. At age 63, approximately one month prior to admission, he began experiencing recurrent upper respiratory symptoms with fevers of around 37°C. He developed a persistent fever of 38°C, accompanied by dyspnea on exertion, and visited the hematology outpatient clinic. Chest radiography revealed prominent pulmonary congestion, leading to the decision to perform echocardiography, which revealed severe aortic valve regurgitation with vegetation attached to the valve. Laboratory findings included a white blood cell count of 13,200/μL and a C-reactive protein (CRP) level of 13.7 mg/dL. Blood cultures revealed the presence of gram-positive cocci. As the patient's respiratory condition progressively worsened, emergency aortic valve replacement was planned. Additionally, because of a history of percutaneous coronary intervention (PCI) at another institution, he was referred for a coronary artery bypass graft (CABG) on the right coronary artery to be performed concurrently. Surgery was performed via median sternotomy under cardioplegic arrest. The aortic valve was perforated at the right coronary cusp and was covered with vegetation. The patient underwent aortic valve replacement with a biological valve, and a saphenous vein graft was used for bypass grafting to the posterior descending branch of the right coronary artery. Postoperatively, antibiotic therapy was administered without infection recurrence. The patient was discharged 47 days postoperatively. This case demonstrated the rapid progression of infective endocarditis following BMT, highlighting the need for prompt recognition and management.