Use of sodC versus ctrA for real-time polymerase chain reaction-based detection of Neisseria meningitidis in sterile body fluids

Fábio Takenori Higa,Claudio Tavares Sacchi,Ana Paula Silva De Lemos,Lee H Harrison,Maria Gisele Gonçalves,Lucila Okuyama Fukasawa,Carla Naufal Da Silva,Priscilla Lima De Oliveira,Maristela Marques Salgado

doi:10.1590/0074-0276108022013020

Fábio Takenori Higa, Claudio Tavares Sacchi + Show 7 more

Open Access

https://doi.org/10.1590/0074-0276108022013020

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Abstract

We evaluated the use of a newly described sodC-based real-time-polymerase chain reaction (RT-PCR) assay for detecting Neisseria meningitidis in normally sterile sites, such as cerebrospinal fluid and serum. The sodC-based RT-PCR assay has an advantage over ctrA for detecting nongroupable N. meningitidis isolates, which are commonly present in asymptomatic pharyngeal carriage. However, in our study, sodC-based RT-PCR was 7.5% less sensitive than ctrA. Given the public health impact of possible false-negative results due to the use of the sodC target gene alone, sodC-based RT-PCR for the diagnosis of meningococcal meningitis should be used with caution.

Highlights

Meningococcal disease (MD) is a serious and often fatal infection
The assay is composed of three sets of primers and three probes targeting the ctrA gene of Neisseria meningitidis (Mothershed et al 2004), the lytA gene of Streptococcus pneumoniae (Carvalho et al 2007) and the bexA gene of Haemophilus influenzae (Corless et al 2001). ctrA is a frequently targeted gene used to detect N. meningitidis using real-time-polymerase chain reaction (RT-PCR) (Corless et al 2001, Mothershed et al 2004)
A new target based on the sodC gene in meningitidis RT-PCR has been proposed as an alternative for clinical specimens, such as cerebrospinal fluid (CSF) and serum (Thomas et al 2011, WHO 2011)

Summary

Introduction

Meningococcal disease (MD) is a serious and often fatal infection. In Brazil, approximately 3,200 new cases of sporadic and outbreak-associated MD are reported each year, making this disease an important public health concern. Our laboratory at Adolfo Lutz Institute (IAL) uses a multiplex real-time-polymerase chain reaction (RT-PCR) assay developed and performed at IAL (Sacchi et al 2011). CtrA is a frequently targeted gene used to detect N. meningitidis using RT-PCR (Corless et al 2001, Mothershed et al 2004).

Results

Conclusion