Clin Exp Emerg Med.  2017 Mar;4(1):25-31. 10.15441/ceem.16.152.

Hematologic parameters to predict negative cerebrospinal fluid examination results among neurologically intact patients who underwent lumbar puncture on suspicion of central nervous system infection

• Kim JH
• Kim HJ
• Na JU
• Han SK
• Choi PC
• Shin DH

• KMID: 2376721
• DOI: http://doi.org/10.15441/ceem.16.152

Abstract

OBJECTIVE
Cerebrospinal fluid (CSF) examination is mandatory whenever central nervous system (CNS) infection is suspected. However, pleocytosis is not detected in a substantial number of suspected patients who undergo CSF examination. This study aimed to identify parameters that can aid in predicting negative CSF examination results (defined as a white blood cell count of <5 cells/high-power field).
METHODS
The study included 101 neurologically intact patients who underwent lumbar puncture because of suspicion of CNS infection. Patients were divided into negative and positive CSF examination groups, and their initial blood tests were comparatively analyzed.
RESULTS
The negative group had a significantly higher proportion of neutrophils in white blood cells (81.5% vs. 75.8%, P=0.012), lower proportion of lymphocytes in white blood cells (9.3% vs. 16.7%, P=0.001), a higher neutrophil-to-lymphocyte ratio (9.1 vs. 4.4, P=0.001), a lower lymphocyte-to-monocyte ratio (1.6 vs. 2.4, P=0.008), and a higher C-reactive protein level (21.0 vs. 5.0 mg/L, P<0.001) than the positive group. In the receiver-operating characteristic analysis, neutrophil-to-lymphocyte ratio and C-reactive protein had an area under the curve of >0.7, and the best cutoff values were 6.0 (accuracy 70.3%) and 12.7 mg/L (accuracy 76.2%), respectively.
CONCLUSION
The neutrophil-to-lymphocyte ratio ≥6 and C-reactive protein level ≥12.7 mg/L was significantly associated with negative CSF examination result.

Keyword

Neutrophils; Neutrophil-to-lymphocyte ratio; C-reactive protein; Central nervous system infection

MeSH Terms

C-Reactive Protein
Central Nervous System Infections*
Central Nervous System*
Cerebrospinal Fluid*
Hematologic Tests
Humans
Leukocyte Count
Leukocytes
Leukocytosis
Lymphocytes
Neutrophils
Spinal Puncture*
C-Reactive Protein