- Ultrasensitive qualitative detection of Neisseria
meningitidis by real time polymerase chain
Neisseria meningitidis is the etiologic agent of meningococcal
meningitis. It is a non-spore forming, gram-negative, nonmotile,
diplococcal bacterium. These bacteria are aerobic and have
fastidious growth requirements, with optimal growth in warm,
moist environments. Five
N. meningitidis serotypes cause most associated disease
worldwide: serotypes circulating in the US are likely to be B,
C, or Y, while serotypes A and W-135 are found outside the US.
The natural habitat of
N. meningitidis is the human nasopharyngeal tract. Five to fifteen
percent of the human population carries the bacteria in its
nonpathogenic form. Infection can occur via respiratory
droplets, but normally requires close and prolonged exposure, or
direct contact with saliva and respiratory secretions. Ill
patients or asymptomatic carriers can transmit the organism.
Meningitis is a common symptom of the resultant infection,
characterized by fever, severe headache and stiff neck. Patients
with meningococcal sepsis may develop high fever, hypotension
(low blood pressure), and profound weakness. In either case,
patients may develop a characteristic rash including petechiae
(pinpoint red spots that do not blanch with pressure) or purpura
(purple areas similar to bruises), that are both caused by
bleeding into the skin. Purpura fulminans, a hemorrhagic
condition causing tissue necrosis and small vessel thrombosis,
can result in scarring or limb amputations. Approximately 10-14%
of cases of meningococcal disease are fatal. About 11-19% of
patients who recover from the infection may develop permanent
hearing loss, mental retardation, loss of limbs or other severe
No known animal reservoir exists for
N. meningitidis; however, experimental infection of nonhuman
primates, mice, guinea pigs and rats has been reported.
Culture detection of N.
meningitidis has low sensitivity because the organism
has fastidious growth requirements. Molecular detection by
PCR can detect N.
meningitidis with high sensitivity and specificity (Sacchi
et al., 2011).
Help confirm the disease causing agent
Shorten the time required to confirm a clinical diagnosis of
Neisseria meningitidis infection.
Help ensure that colonies are free of N. meningitidis
Early prevention of spread of N. meningitidis
Minimize personnel exposure to N. meningitidis
Safety monitoring of biological products
Sacchi, C.T., Fukasawa,
L.O., Gonçalves, M.G., Salgado, M.M., Shutt, K.A., Carvalhanas,
T.R., Ribeiro, A.F., Kemp, B., Gorla, M.C., Albernaz, R.K.,
Marques, E.G,, Cruciano, A., Waldman, E.A., Brandileone, M.C.,
Harrison, L.H,. São Paulo RT-PCR Surveillance Project Team.
(2011) Incorporation of real-time PCR into routine public health
surveillance of culture negative bacterial meningitis in São
Paulo, Brazil. PLoS One. 6:e20675.
Nasal swab, or
throat swab, or 0.5 ml whole blood in EDTA (purple top) or ACD
(yellow top) tube; or 0.5 ml CSF, or aspirate from skin lesions,
or cell culture.
For specimen types other than those listed here, please call to
confirm specimen acceptability and shipping instructions.
For all specimen types, if there will be a delay in shipping, or
during very warm weather, refrigerate specimens until shipped
and ship with a cold pack unless more stringent shipping
requirements are specified. Frozen specimens should be shipped
so as to remain frozen in transit. See
shipping instructions for
Turnaround time: 2 business days
Qualitative real time PCR
Normal range: Nondetected