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cause of shunt infection. This procedure is usually performed by a neurosurgeon,
if possible. The results of this procedure are sometimes helpful but not always
determinate; the white blood cell (WBC) count can range from 0 to 2,600 if the
shunt is infected, and patients without infection can have up to 500 WBCs/mm3.
In the absence of a positive culture result, many clinicians use more than 50
WBCs/mm3 in the presence of fever, shunt malfunction, and neurologic or
abdominal symptoms to arrive at the diagnosis. Gram stain of the fluid may be
helpful in broadening antibiotic coverage if gram-negative organisms are present.
However, the Gram stain should not be used to narrow the usual antibiotic
coverage until the culture and sensitivities of the causative organisms are
obtained. Most neurosurgeons are reluctant to perform shunt taps in patients with
subtle neurologic complaints and vague infectious signs because of the purported
risk of “seeding” the shunt with skin flora. This risk has never been clearly
defined prospectively, but in a neurologically normal child, it is prudent to
perform a thorough fever workup for common infectious sources to avoid even a
small risk of causing a shunt infection.
Patients with ventriculoperitoneal shunt (VPS) who complain of abdominal
pain, with or without fever, may benefit from abdominal radiographs and
ultrasound to search for a loculated CSF collection or pseudocyst, or visceral
perforation.
Various permutations of medical and surgical therapy have been suggested for
the treatment of proximal CSF shunt infections. Medical therapy alone has been
found to have a relatively low success rate compared with a combined medical–
surgical approach. Potential surgical interventions include immediate shunt
replacement or the insertion of an extraventricular drainage (EVD) catheter,
followed by delayed shunt revision. The latter method improves the bacteriologic
cure rate significantly, although it must be performed in an institution that is
facile in managing and preventing infection of EVD catheters. Distal shunt
infections are treated with antibiotics and temporary externalization of the distal
shunt catheter.
Medical therapy provided in the ED for children with suspected CSF shunt

infections is limited to the administration of broad-spectrum IV antibiotics. The
antibiotics should be effective against S. epidermidis, S. aureus , and gramnegative organisms, as well as any organisms identified from previous infections,
and expanded to treat Pseudomonas aeruginosa infections in severely ill patients.
A reasonable choice of empiric therapy is cefepime followed by vancomycin.
Ciprofloxacin can be substituted for Cefepime in patients with documented