Staphylococcus epidermidis ventriculoperitoneal shunt infection

Staphylococcus epidermidis is the most common cause of cerebrospinal fluid shunt infections, causing more than 50% of cases in one series ¹⁾.

The affinity of S. epidermidis for medical devices, such as ventriculoperitoneal shunt , has been attributed to its ability to adhere to plastics, with the subsequent formation of biofilm which can reduce efficacy of treatment and cause persistence of infection ²⁾.

The insertion of medical devices, such as intraventricular shunts, is often complicated by infection leading to ventriculitis. Frequently, such infections result from colonisation and subsequent biofilm formation on the surfaces of the shunts by Staphylococcus epidermidis. The pathogenesis of neurosurgical shunt infections is complex with interactions between the pathogen, the device and the unique local immunological environment of the central nervous system (CNS).

An ability to form biofilm, the main virulence determinant of Staphylococcus epidermidis, facilitates protection of the organism from the host defences while still initiating an immunological response. The presence of the blood brain barrier (BBB) and the biofilm itself also complicates treatment, which presents many challenges when managing shunt infections. A greater understanding of the interplay between S. epidermidis and the CNS could potentially improve the diagnosis, treatment and management of such infections ³⁾.

A study group involved 30 children with congenital hydrocephalus after shunt system implantation, whose procedures were complicated by S. epidermidis implant infection. Thirty children with congenital hydrocephalus awaiting their first-time shunt implantation formed the control group. The level of eosinophils in peripheral blood was assessed in both groups. Cerebrospinal fluid (CSF) was examined for protein level, pleocytosis, interleukins, CCL26/Eotaxin 3, IL-5, IL-6, CCL11/Eotaxin-1, CCL3/MIP-1a, and MBP. Three measurements were performed in the study group. The first measurement was obtained at the time of shunt infection diagnosis, the second one at the time of the first sterile shunt, and the third one at the time of shunt reimplantation. In the control group, blood and CSF samples were taken once, at the time of shunt implantation.

In the clinical material, the highest values of eosinophils in peripheral blood and CSF pleocytosis were observed in the second measurement. It was accompanied by an increase in the majority of analyzed CSF interleukins.

Cerebrospinal fluid pleocytosis observed in the study group of Polis et al., from the Department of Neurosurgery, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland. shortly after CSF sterilization is presumably related to an allergic reaction to Staphylococcus epidermidis, the causative agent of ventriculoperitoneal shunt infection ⁴⁾.

Linezolid, an oxazolidinone, is active against Gram positive cocci, and has excellent CSF penetration. Gill et al., present a 22-year-old woman who was cured of a Staphylococcus epidermidis VP shunt infection via shunt removal and intravenous linezolid ⁵⁾.