High-Grade Staphylococcus lugdunensis Bacteremia in a Patient on Home Hemodialysis.

Background: Staphylococcus lugdunensis (S lugdunensis) is a species of coagulase-negative Staphylococcus and a constituent of human skin flora. S lugdunensis has gained notoriety for its virulence, which resembles Staphylococcus aureus (S aureus). S lugdunensis is now recognized as an important nosocomial pathogen and cause of prosthetic device infections, including vascular catheter infections.

Case presentation: A 60-year-old man with a history of uncontrolled type 2 diabetes mellitus and end-stage renal disease on home hemodialysis via arteriovenous fistula (AVF) presented to the emergency department for evaluation of subacute progressive low back pain. Initial laboratory tests were notable for elevated inflammatory markers. Magnetic resonance imaging with contrast of the thoracic and lumbar spine revealed abnormal marrow edema in the T11-T12 vertebrae with abnormal fluid signal in the T11-T12 disc space. Cultures grew methicillin-sensitive S lugdunensis. The patient's antibiotic regimen was narrowed to IV oxacillin. He was transitioned to IV cefazolin dosed 3 times weekly after hemodialysis and an outpatient dialysis center.

Conclusions: Treatment of bacteremia caused by S lugdunensis or S aureus should be managed with prompt initiation of IV antistaphylococcal therapy, a thorough evaluation for the source of bacteremia as well as metastatic complications, and consultation with an infectious disease specialist. This case highlights AVF as a potential source for infection even without localized signs of infection. The buttonhole method of AVF cannulation was thought to be a major contributor to the development and persistence of our patient's bacteremia. This risk should be discussed with patients using a shared decision-making approach when developing a dialysis treatment plan.