Nosocomial ventriculitis and meningitis in neurocritical care patients

External ventricular drainage (EVD) is frequently necessary in neurological and neurosurgical intensive care patients. A major complication of this procedure is an EVD-related venticulitis or meningitis. The purpose of this review is (1) to address the magnitude of the problem in the neurocritical care patient population, (2) to discuss the difficulties in providing an appropriate and timely diagnosis of this disease entity and (3) to propose an algorithm for both rapid diagnosis and appropriate therapy. A MEDLINE literature search was carried out for studies from January 1990 through March 2008 reporting on ventriculostomy, EVD-related central nervous system infections, in particular ventriculitis and meningitis. EVD-related ventriculitis is a serious nosocomial complication in the neurocritical care setting where EVD catheters are frequently used for the management of elevated ICP secondary to acute hydrocephalus primarily caused by subarachnoid and intraventricular hemorrhage or traumatic brain injury. Infection rate is high with reported incidences in the range of 5 % up to more than 20 %. Predisposing factors for infection are non-adherence to rigid insertion and maintenance protocols, leakage of cerebrospinal fluid (CSF), catheter irrigation and the frequency of EVD manipulation. Diagnosis is frequently impaired either by the presence of systemic inflammation due to the primary disease or because the hemorrhagic CSF itself may cause an inflammatory reaction. Furthermore, the most common pathogens involved in EVD-related infections, i. e., staphylococci, initially provoke only a mild inflammatory response in the CSF and therefore patients rarely present with clear-cut clinical signs indicating severe central nervous system infection, in particular, ventriculitis. Nosocomial EVD-related ventriculitis is a significant cause of morbidity and mortality in critically ill neurological patients. Rapid diagnosis and prompt initiation of appropriate antimicrobial therapy is needed. A stepwise algorithm for the management of EVD-related ventriculitis is proposed.