Fatal Recurrent Staphylococcus aureus Infection in a Patient With an Aortic Endostent Under Alirocumab

Aortic stent-graft infection (SGI) entails a high mortality. Alirocumab is a monoclonal antibody to proprotein convertase subtilisin/kexin type 9 (PCSK9), approved for treatment of therapy-refractory hypercholesterolemia. Proprotein convertase subtilisin/kexin type 9 might play a role in infections.

A 68-year-old male suffered from fatigue, fever, and back pain. Twelve months previously, a 4-fold-fenestrated aortic endoprosthesis was implanted because of an aortic aneurysm. Four months later, alirocumab 150 mg was initiated. Staphylococcus aureus grew in several blood cultures, and he received cefazolin and fosfomycin. Fludeoxyglucose positron emission tomography computed tomography indicated an infected endoprosthesis. Puncture of the periprosthetic space under antibiotic therapy revealed different strains of Staphylococcus epidermidis. The therapy was changed to dalbavancin. The patient died suddenly 11 days later after complaining about back pain for several days. No autopsy was carried out.

The most probable cause of the patient's recurrent bacteremia with S aureus was an infection of the aortic prosthesis. Although this report is very speculative, it can be concluded that data about infections in patients under PCSK9 inhibitors should be collected systematically and more research is needed about the biological consequences of decreasing cholesterol to extreme low levels.