Revision Surgeries Are Associated With Significant Increased Risk of Subsequent Cerebrospinal Fluid Shunt Infection

Abstract

The object of this study was to determine whether cerebrospinal fluid (CSF) shunt revision(s) are associated with increased risk of CSF shunt infection, after adjusting for baseline factors that contribute to infection risk. This was a retrospective cohort study of 579 children aged 0-18 years who underwent initial CSF shunt placement between January 01, 1997 and October 12, 2006 at a tertiary care children's hospital. The outcome of interest was CSF shunt infection. Data for all subsequent CSF shunt revisions leading up to and including the initial CSF shunt infection, when applicable, were obtained. The likelihood of infection was determined using a Cox proportional hazard model accounting for patient characteristics and CSF shunt revisions, and is reported using hazard ratios (HR) with 95% confidence intervals (CI). There were 123 children who developed infection. Baseline factors independently associated with hazard of infection included age 0 to <6 months at CSF shunt placement (HR 2.4, 95% CI: 1.02-6.7) and myelomeningocele (HR 0.4, 95% CI: 0.2-0.8). Controlling for baseline factors, the risk of infection after shunt revision was significantly greater than at the time of initial placement (HR 3.0, 95% CI: 1.9-4.7), and this risk increased as numbers of revisions increased (≥2 revisions HR 6.5, 95% CI: 3.6-11.4). Although younger age is associated with increased hazard of infection, subsequent CSF shunt revision significantly increases infection risk.