Towards accurate exclusion of neonatal bacterial meningitis: a feasibility study of a novel 16S rDNA PCR assay.
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 (EppendorfTM) 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.
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Due to technical limitations, tables are only available as a download in the supplemental files section
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Posted 13 Jun, 2020
On 09 Jun, 2020
Received 14 Dec, 2019
Received 14 Dec, 2019
On 25 Nov, 2019
On 20 Nov, 2019
Invitations sent on 20 Nov, 2019
On 20 Nov, 2019
On 13 Nov, 2019
On 13 Nov, 2019
On 12 Nov, 2019
Towards accurate exclusion of neonatal bacterial meningitis: a feasibility study of a novel 16S rDNA PCR assay.
Posted 13 Jun, 2020
On 09 Jun, 2020
Received 14 Dec, 2019
Received 14 Dec, 2019
On 25 Nov, 2019
On 20 Nov, 2019
Invitations sent on 20 Nov, 2019
On 20 Nov, 2019
On 13 Nov, 2019
On 13 Nov, 2019
On 12 Nov, 2019
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 (EppendorfTM) 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.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Due to technical limitations, tables are only available as a download in the supplemental files section