Incidence and Prevalence
- 5–15% incidence: The published rates of CSF shunt infection case incidence range from less than 1% in a single report using a strict shunt insertion protocol to a mean of 5–15%, but there are reports where the incidence is up to 40% (65).
- Majority within 6 months of implant: A bimodal distribution of infection has been observed, with most of the episodes occurring within the first 6 months after implantation and a second peak after 12 months (1, 4, 5, 6, 7, 8, 11, 15, 18, 22, 28, 29, 34, 36, 37, 41, 47).
- Highest rate within medical implantable devices: CSF shunt systems carry infection rates that not only are higher than rates associated with other neurosurgical implantable devices such as deep brain and vagus nerve stimulators (1.8 to 6% in the former and 1- 3.5% in the latter) but also are greater than infection rates associated with other silicone-encapsulated devices such as breast implants (2-2.5%) (124).
- Most in children under 2 years: Age plays an important role in shunt infections, as host mechanisms of defense are impaired in many ways. Most cases occur in very-low-weight preterm infants and children younger than 2 years of age (61, 89, 126).
- No known sex predilection: On the basis of published literature, there appears to be no gender predilection for CSF shunt infection (74, 89).
- Recent review shows even distribution globally: Rates of shunt infection have been reported as higher in third world health institutions (111). However, recent reports have shown a low uniform rate when strict protocols are followed regardless of geographical location (146).
Children who undergo shunting may have associated factors that can lead to an increased incidence of shunt infections. These factors are summarized in the table below.
Associated Risk Factors for Shunt Infection
|Prematurity and low weight (<2000 g)|
|Recent myelomeningocele closure|
|Prolonged NICU stay|
|Postoperative CSF fistula|
|Surgical wound dehiscence/suture material rejection|
|Neonatal sepsis/intraventricular hemorrhage|
|Multiple indwelling catheters|
|Previous episode of shunt infection|
|Malignant blood and solid tissue tumors|
|Impaired immune system (congenital, post- chemotherapy)|
|Use of broad spectrum antibiotics|
|Shunt device-related factors|
|High profile devices|
|Prolonged exposure of shunt components to OR room air after opening the sterile packaging|
|Repeated shunt tapping/shunt revisions|
Amount of subcutaneous shunt material, especially distal shunt catheter
Catheter coating with BioGlide®.
|Multiple previous surgeries in same OR suite on same day|
|High OR personnel traffic|
|Inadequate OR climate control/ laminar flow suites|
|Expertise on shunting procedures|
|Following strict shunting procedure protocol|
Relationships to Other Disease States and Syndromes
- Impaired immune system: Certain pediatric populations have an increased tendency to develop CSF shunt infection, such as those with low birth weight, associated neonatal sepsis, and compromised immunity associated with malnutrition, chemotherapy, and systemic illnesses (10, 35, 39, 81, 105, 116, 139, 158).
- Other invasive procedures: Surgical procedures that involve potential contamination of the target cavity of a shunt must be considered, and the distal catheter must be isolated during such procedures (e.g., a bowel procedure in a child with a peritoneal catheter). Patients who undergo dental procedures are also at risk and should receive prophylactic antibiotic therapy. Although no shunt infections have been reported after peritoneal dialysis, some have suggested that patients with spina bifida who require peritoneal dialysis are at risk for their peritoneal catheters becoming infected from a related peritonitis and have suggested ventriculoatrial shunts as an option (83, 92, 102, 163).