Low Yield of Positive Cerebrospinal Fluid (CSF) Culture and Bacterial PCR Tests In Paediatric Patients With A Normal CSF White Cell Count

Area of Science:

• Pediatric Infectious Diseases
• Clinical Microbiology
• Neuroscience

Background:

• Bacterial meningitis can present with elevated cerebrospinal fluid (CSF) white cell counts.
• Atypical presentations, including normal CSF white cell counts, can occur in pediatric bacterial meningitis.
• Diagnostic accuracy of CSF analysis is crucial for timely treatment.

Purpose of the Study:

• To review pediatric patients with laboratory-confirmed bacterial meningitis despite normal CSF white cell counts.
• To evaluate the clinical significance and diagnostic utility of bacterial PCR in such cases.
• To provide guidance on the appropriate use of bacterial PCR testing in pediatric meningitis.

Main Methods:

• Retrospective review of pediatric patients with positive CSF culture or bacterial PCR results.
• Inclusion criteria: CSF sample for culture (2005-2015) or bacterial PCR (2010-2015).
• Exclusion criteria: Neurosurgical and neurology patients; analysis of CSF white cell counts and diagnostic methods.

Main Results:

• 101 pediatric patients had laboratory-confirmed bacterial meningitis.
• 18% of these patients presented with normal CSF white cell counts for age.
• Only one case with a normal CSF white cell count was clinically significant, occurring after prolonged antibiotic treatment.

Conclusions:

• Normal CSF white cell counts can occur in pediatric bacterial meningitis, though infrequently.
• Routine bacterial PCR testing in patients with normal CSF white cell counts is not advised.
• Bacterial PCR should be reserved for cases with positive blood cultures or specific clinical indications by senior pediatricians.