Infection of cerebrospinal fluid shunt

ABSTRACT

Aims of this study were to determine the infection rate in patients who underwent cerebrospinal fluid shunt [CSF], and to identify the risk factors in aetiology of the infection. Retrospective analysis of 94 patients underwent some form of CSF shunt surgery [177 procedures] at Salmaniya Medical Complex. Medical records were reviewed; patient's age, diagnosis, and cause of hydrocephalus were confirmed; type of shunt, number of procedures in each patient, infection and causative microorganisms were identified. Infection of CSF shunt was defined by the presence of microorganisms in the CSF or shunt colonisation with microorganism seen on microscopic examination or grown from culture of CSF, or the catheter, in association with clinical features of infection. All patients received antibiotics at induction of anaesthesia and at least 48 hours postoperatrvely. All shunts were flushed and primed with antibiotic containing solution. Exclusion criteria 1. Patients underwent external ventricular drainage only. 2. Patient underwent endoscopic third ventriculostomy only. 3. Patients underwent CSF diversion in other hospital. 4. Patients with sepsis not related to their CSF shunt. A total of 94 patients underwent 177 CSF shunt surgeries between January 1993 and December 2002. Age range was 0-20 years. Mean age was 8 years. There were 56 males and 38 female. Cerebrospinal fluid shunt included ventriculoperitoneal shunt [VP shunt] 173 [97.7%] procedures, lumboperitoneal shunt [LP shunt] 1 [0.6%] procedure, subdural peritoneal shunt 2 [1.1%] procedures, and Dandy-Walker cystoperitoneal shunt 1 [0.6%] procedure. Infection was documented in 14 [14.89%] patients out of 94 shunted individuals. Infection rate was 17.5% in 31 procedures out of 177 over a period of 10 years. Staphylococcus aureus was isolated in 25.8% of procedures, staphylococcus epidermides in 19.4%, klebsiella pneumonia 14%, pseudomonas aeruginosa in 9.7%, enterococci in 14%, beta-haemolytic streptococci in 7%, E coli in 7%, Candida albicans in 3%, and Mozzarrolla catarrhalis in 3%.Risk factors included premature infants, repeated revisions of the shunts, and environment at which the shunt was reviewed. Our infection rate was higher than other Neurosugical centres. The risk of cerebrospinal shunt infection may be reduced or minimised and risk factors should be identified. Prematurity in hydrocephalic newboms is considered as a risk factor for shunt infection; precautions and alternatives to shunt placement in premature infants may be adopted like delaying the CSF diversion if neurological condition of the infant permits and infants body weight exceeds 2 kgs. Strict adherence to meticulous non-touch surgical technique of shunt system is an essential factor in prevention of infection. Minimising the operative time is another factor that should be respected. Cerebrospinal fluid shunt procedures must be performed in a clean neurosurgical operating room, even in emergency situations. If infection takes place, it should be managed by antibiotics with removal of the infected shunt and external ventricular drainage