External ventricular drain (EVD)-associated ventriculitis is a serious complication. Early diagnosis can be difficult particularly in critically ill patients with aneurysmal subarachnoid hemorrhage (aSAH). We examined the diagnostic potential of standard serum and cerebrospinal fluid (CSF) biomarkers to differentiate between EVD-associated infections and aseptic courses in patients with aSAH.
We retrospectively evaluated the levels of inflammatory markers in serum (white blood cell count, percentage of neutrophils [sN%], and procalcitonin) and CSF (total leukocyte count [CSFTLC], CSFglucose, CSF/serumglucose ratio, CSF total protein [CSFTP]) of 63 consecutive patients with aSAH. Receiver operating characteristic curves and the area-under-the-curve (AUC) were calculated to detect the diagnostic potential, optimized threshold, sensitivity (SE), specificity (SP), + likelihood ratio (LR), and −LR of each biomarker.
Of all patients, 17 (27%) developed an EVD-associated ventriculitis within a mean of 7.8±2.3 days after implantation. sN% had a very good diagnostic potential (AUC=0.900, SE=70.0%, SP=100%), followed by the CSFTLC with good diagnostic potential (AUC=0.841, SE=75.0%, SP=88.5%), and the CSFTP with moderate diagnostic potential (AUC=0.772, SE=73.3%, SP=76.0%). sN% higher than 70% and a CSFTLC higher than 635/µL were highly associated with the diagnosis of ventriculitis (+LR=∞ and 6.5), sN%<70% or a CSFTLC<635 made a diagnosis of ventriculitis unlikely (−LR=0.3 and 0.28).
Routine determination of N% and CSFTLC are useful to distinguish ventriculitis from aseptic courses in the acute phase after aSAH and regardless of the bacteriological test result.
Departments of *Neurosurgery
†Anesthesiology, Hospital of the University of Munich – Campus Großhadern, LMU, Marchioninistr., Munich, Germany
The authors have no funding or conflicts of interest to disclose.
Address correspondence to: Markus Lenski, MD, Department of Neurosurgery, Hospital of the University of Munich – Campus Großhadern, LMU, Marchioninistr. 15, Munich 81377, Germany (e-mail: firstname.lastname@example.org).
Received August 11, 2017
Accepted January 15, 2018