Challenges in treating Staphylococcus epidermidis ventriculitis:The role of biofilm formation and antimicrobial resistance

Abstract

Ventriculitis caused by Staphylococcus epidermidis presents significant management challenges due to biofilm formation and antimicrobial resistance, particularly in patients with external ventricular drains (EVDs). This case report highlights the complexities of treating S. epidermidis-associated ventriculitis and the role of combination antibiotic therapy in overcoming persistent infection.

A 54-year-old male with diabetes mellitus and hypertension presented with altered mental status and was diagnosed with a spontaneous hemorrhage in the left basal ganglia. An EVD was placed for intracranial pressure management, but the patient subsequently developed ventriculitis, confirmed by cerebrospinal fluid (CSF) cultures positive for S. epidermidis. Initial treatment with IV Vancomycin failed to eradicate the infection, prompting the addition of Rifampin, a strategy supported by literature on biofilm-associated infections. The patient’s clinical course was further complicated by a non-occlusive pulmonary embolism.

This case underscores the limitations of vancomycin monotherapy against biofilm-associated S. epidermidis infections and highlights the efficacy of Rifampin in achieving bacterial clearance. Notably, CSF cultures remained persistently positive until rifampin was introduced, leading to the first negative culture and eventual placement of a ventriculoperitoneal shunt. Coagulase-negative staphylococci, including S. epidermidis, account for 50-75% of central nervous system (CNS) shunt infections and typically elicit a less robust inflammatory response, complicating early diagnosis. Our findings emphasize the need for early recognition of biofilm formation and prompt initiation of targeted antimicrobial therapy to improve outcomes in CNS device-related infections. This case supports the use of combination antibiotic therapy and device management as critical components in treating biofilm-associated ventriculitis.

Keywords: Staphylococcus epidermidis, ventriculitis, biofilm, rifampin, antimicrobial resistance