Related Experiment Video
Updated: Dec 17, 2025
High-throughput Detection of Respiratory Pathogens in Animal Specimens by Nanoscale PCR
Published on: November 28, 2016
Towards accurate exclusion of neonatal bacterial meningitis: a feasibility study of a novel 16S rDNA PCR assay
Arthur Abelian1, Thomas Mund2, Martin D Curran3
1Department of Paediatrics, Maelor Hospital, Betsi Cadwaladr University LHB, 12 Fleming Drive, Wrexham, LL11 2BP, UK. abelartur@doctors.org.uk.
Background:
PCRctic is an innovative assay based on 16S rDNA PCR technology that has been designed to detect a single intact bacterium in a specimen of cerebro-spinal fluid (CSF). The assay's potential for accurate, fast and inexpensive discrimination of bacteria-free CSF makes it an ideal adjunct for confident exclusion of bacterial meningitis in newborn babies where the negative predictive value of bacterial culture is poor. This study aimed to stress-test and optimize PCRctic in the "field conditions" to attain a clinically useful level of specificity.
Methods:
The specificity of PCRctic was evaluated in CSF obtained from newborn babies investigated for meningitis on a tertiary neonatal unit. Following an interim analysis, the method of skin antisepsis was changed to increase bactericidal effect, and snap-top tubes (Eppendorf™) replaced standard universal containers for collection of CSF to reduce environmental contamination.
Results:
The assay's specificity was 90.5% in CSF collected into the snap-top tubes - up from 60% in CSF in the universal containers. The method of skin antisepsis had no effect on the specificity. All CSF cultures were negative and no clinical cases of neonatal bacterial meningitis occurred during the study.
Conclusions:
A simple and inexpensive optimization of CSF collection resulted in a high specificity output. The low prevalence of neonatal bacterial meningitis means that a large multi-centre study will be required to validate the assay's sensitivity and its negative predictive value.
Insights
Optimizing cerebrospinal fluid collection methods significantly improved the specificity of the PCRctic assay for detecting bacterial meningitis in newborns. This enhancement aids in accurately ruling out bacterial meningitis when cultures are negative.
Area of Science:
- Microbiology
- Neonatal Medicine
- Diagnostic Assay Development
Background:
- PCRctic is a 16S rDNA PCR assay designed to detect single bacteria in cerebrospinal fluid (CSF).
- It offers potential for rapid, cost-effective exclusion of bacterial meningitis in neonates, where culture sensitivity is limited.
- This study aimed to optimize PCRctic under real-world conditions to improve its specificity.
Purpose of the Study:
- To evaluate and enhance the specificity of the PCRctic assay for bacterial meningitis detection in newborns.
- To identify optimal methods for CSF collection to minimize contamination and maximize assay performance.
Main Methods:
- The specificity of PCRctic was assessed using CSF samples from neonates suspected of meningitis.
- CSF collection methods were modified, changing skin antisepsis and switching to snap-top tubes for sample collection to reduce environmental contamination.
Main Results:
- Specificity increased from 60% with universal containers to 90.5% with snap-top tubes.
- Changes in skin antisepsis method did not impact specificity.
- All CSF cultures were negative, and no cases of neonatal bacterial meningitis were clinically diagnosed.
Conclusions:
- A simple optimization in CSF collection technique substantially improved PCRctic assay specificity.
- Further multi-center studies are necessary to validate the assay's sensitivity and negative predictive value due to the low prevalence of neonatal bacterial meningitis.
