title: The diagnostic value of cerebrospinal fluids procalcitonin and lactate for the differential diagnosis of post-neurosurgical bacterial meningitis and aseptic meningitis.
abstract: OBJECTIVE
  Distinguishing between post-neurosurgical bacterial meningitis (PNBM) and aseptic meningitis is difficult. This study aims to evaluate the combined diagnostic value of CSF procalcitonin and lactate as novel PNBM markers in hospitalized post-neurosurgery patients.
  
  
  METHODS
  This study was performed using CSF samples, collected by lumbar puncture, from 178 PNBM-suspected patients enrolled in a retrospective clinical study. The levels of CSF procalcitonin and lactate were appropriately assayed and the combined diagnostic value of these markers was assessed using receiver operating characteristic (ROC) curves, a two by two table, and non-parametric tests.
  
  
  RESULTS
  Fifty of the 178 patients were diagnosed with PNBM, based on the clinical symptoms and laboratory results. These PNBM patients showed significantly elevated levels of CSF procalcitonin and CSF lactate compared with the non-PNBM group (p<0.001 for both). It was revealed that the cut-off values for the diagnosis of PNBM were: 0.075ng/mL (sensitivity, 68%; specificity, 73%) for procalcitonin and 3.45mmol/L (sensitivity, 90%; specificity, 85%) for lactate. A serial test combining the levels of these two markers showed decreased sensitivity (64%) and increased specificity (91%), compared with either marker alone. In contrast, a parallel test combining the levels of these both markers showed increased sensitivity (96%) and decreased specificity (65%), compared with either marker alone.
  
  
  CONCLUSIONS
  Our study shows that the combined use of CSF procalcitonin and lactate can reliably distinguish between PNBM and non-PNBM and can be included in the design of diagnostic approaches to circumvent the shortcomings of conventional methods.
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Youran
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, Beijing, China. Electronic address: tiantanzgj@163.com.
authors.forename: Guojun
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Ruimin
authors.initials: R
authors.lastname: Ma
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Yamei
authors.initials: Y
authors.lastname: Du
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Fangqiang
authors.initials: F
authors.lastname: Li
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Lv
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Beijing Tiantan Hospital, Capital Medical University, Beijing, China; China National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
authors.forename: Xixiong
authors.initials: X
authors.lastname: Kang
mesh_terms: D000293:Adolescent; D000328:Adult; D002116:Calcitonin / Q000134:cerebrospinal fluid*; D015740:Calcitonin Gene-Related Peptide; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000134:cerebrospinal fluid*; D008297:Male; D008582:Meningitis, Aseptic / Q000134:cerebrospinal fluid* / Q000175:diagnosis*; D016920:Meningitis, Bacterial / Q000134:cerebrospinal fluid* / Q000175:diagnosis*; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D011498:Protein Precursors / Q000134:cerebrospinal fluid*; D012372:ROC Curve; D055815:Young Adult
chemical_list: C000606589:CALCA protein, human; D011498:Protein Precursors; D019344:Lactic Acid; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide
keywords: Bacterial meningitis; CSF; Lactate; Procalcitonin