Aseptic meningitis

Prof. Alain Gervaix

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Aseptic meningitis

TERMINOLOGY:

o Meningitis is inflammation of meninges

o Meninges are the membranes that

envelop the central nervous system

(cerebrum and spinal cord)

o Meninges consist of 3 layers: the dura

mater, the arachnoid mater, and the pia

mater

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Aseptic meningitis

ANATOMY:

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Aseptic meningitis

ANATOMY:

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Aseptic meningitis

TERMINOLOGY:

o ASEPTIC MENINGITIS is the clinical

syndrome of meningeal inflammation

with NEGATIVE CULTURE FOR ROUTINE

BACTERIAL PATHOGENS in a patient who

did not receive antibiotics before lumbar

puncture

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Aseptic meningitis

ETIOLOGY:

o Aseptic meningitis has a number of

infectious causes

http://www.uptodate.com/contents/viral-meningitis

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Aseptic meningitis

ETIOLOGY:

o Aseptic meningitis has a number of

infectious causes

o Viruses (usually enterovirus) are the most

common pathogens.

o Because viruses are the most common

cause of aseptic meningitis, the terms of

aseptic meningitis and viral meningitis are

sometimes used synonymously

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Aseptic meningitis

ETIOLOGY:

o Aseptic meningitis has also a

number of non-infectious causes

http://www.uptodate.com/contents/viral-meningitis

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Aseptic meningitis

Cases of aseptic meningitis have been reported after

immunization with several live attenuated virus vaccine

including:

o Oral polio

o Combined measles-mumps-rubella (MMR)

o Varicella

o Yellow fever

o Smallpox

o Rabies

Occurrence 2-7 weeks following immunization

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Estimates of the incidence of aseptic meningitis associated

with mumps vaccine have varied widely. Discrepancies in

estimated rates are likely due to differences in study design or

case ascertainment, age-specific immunity or vaccine strains.

Reported incidences have ranged from a frequency of

o 1: 2041 for the Urabe strain to

o 1 > 1,800,000 for Jeryl-Lynn.

In one study, the incidence of aseptic meningitis after mass

immunization with measles–rubella vaccine (i.e., without a

mumps vaccinestrain) has been reported to be low with an

incidence of 1:867,000 doses.

Aseptic meningitis following immunization usually is

benign and resolves without sequelae

Aseptic meningitis

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Aseptic meningitis

CLINICAL FEATURES:

o The manifestations of viral meningitis are

generally similar to those of bacterial

meningitis, but often less severe

o Signs and symptoms of aseptic meningitis in

children vary with age, immune status, and

etiologic agent

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Aseptic meningitis

Abrupt onset of fever

Nonspecific symptoms o Thermal instability

o Poor feeding

o Vomiting

o Diarrhea

o Rash

Neurologic symptoms o None (to)

o High pitched cry

o Irritability and lethargy

o Nuchal rigidity

o Bulging fontanelle

o Convulsion

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Aseptic meningitis

Abrupt onset of fever

Headache (81-100%)

Nausea

Vomiting (70-92%)

Stiff neck (39-70%)

Photophobia

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Aseptic meningitis

Bulging fontanelle

Nuchal rigidity

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Aseptic meningitis

o Bacterial meningitis

(always treat with antibiotics if suspicion)

o Encephalitis

Personnality changes, alteration of consciousness,

absent eye contact, diminished response to painful stimuli

Seizures

Neurologicalsigns of focal deficits

o Malaria (cerebral) Positive Plasmodium falciparum in blood or CSF

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Aseptic meningitis

o Because signs and symptoms cannot

differentiate viral from bacterial meningitis

o Because outcome is dramatically different

in viral and bacterial meningitis (excellent

and poor, respectively)

a precise diagnosis is required

and necessitates a

LUMBAR PUNCTURE

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Aseptic meningitis

To see a video of lumbar puncture go to:

http://www.nejm.org/doi/full/10.1056/NEJ

Mvcm054952

DIAGNOSTIC PROCEDURE:

Lumbar puncture

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Aseptic meningitis

LUMBAR PUNCTURE:

In the Cerebral Spinal Fluid (CSF) determine :

o Pressure

o Aspect /color

o Cell count

o Protein

o Glucose

o Gram / Ziehl stain

o Culture

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Normal values Bacterial meningitis TB meningitis Viral meningitis

Pressure < 8cm H2O increased ++ variable increased +

Aspect clear, colorless yellowish, turbid yellowish, viscous clear fluid

Cell count/mm3 < 5 leuco > 1'000 leuco 10 -500 leuco 10 -500 leuco

neonate < 25 > 80 % neutrophils > 50% lympho > 50% lympho

Protein < 0.4 g/L 0.5 - 6.0 g/L 1.0 - 5.0 g/L 0.1 - 1.0 g/L

neonate < 1.5 g/L

Glucose > 2.2 mmol/L* low low normal

Gram/Ziehl stain negative Gram: positive Ziehl: positive negative

Culture negative positive positive negative

Aseptic meningitis

CSF value in meningitis

Frequent overlap of values * > 0.4g/L

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The most common bacteria in meningitis

beyond the neonatal period are

- Streptococcus pneumoniae

- Haemophilus influenzae type B

- Neisseria meningitidis

(sérogroupe A, B, C, Y, W135)

Diplococci positive

gram stain

Rods negative gram

stain

Diplococci negative

gram stain

Aseptic meningitis

In aseptic meningitis Gram stain must be always NEGATIVE

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Aseptic meningitis

A score of 0 rules out a bacterial meningitis by 100% (95 CI 97%-100%)

A score ≥ 2 predicts a bacterial meningitis by 87%

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Aseptic meningitis

Blood tests

o White blood cell count (WBC)

o WBC and abslute neutrophil counts (ANC) are elevated in bact. meningitis

o Blood culture

o Keep one more tube of blood for freezing (for later serology, other..)

o HIV serologies

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Aseptic meningitis

Keep a CSF sample for supplementary examinations

o PCR test for viruses, bacteria and parasites o Toxin investigation

o Autoantibodies

Aseptic meningitis

Other exams (in case of diagnostic doubt)

o Cerebral imaging (Ct-scan, MRI) especially if suspicion of

encephalitis

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Aseptic meningitis

o No antibiotic treatment is required in aseptic

meningitis

o Symptomatic treatment

Rest in a quiet, dimly lit room

Acetaminophen, ibuprofen for headache, pain and fever

(avoid aspirin)

TREATMENT

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Aseptic meningitis

Level 1 diagnostic certainty

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Aseptic meningitis

Level 2 diagnostic certainty

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Aseptic meningitis

REFERENCES

T. Tapiainen, et al. « Aseptic meningitis: Case definition and

guidelines for collection, analysis and presentation of immunization

safety data »

Vaccine ( 2007) 25: 5793 - 5802

DM Kulik, et al. « Does this child have bacterial meningitis? A

systematic review of clinical prediction rules for children with

suspected bacterial meningitis »

J Emerg Med. ( 2013) 45(4):508-19.

Nigrovic LE, et al. « Meta-analysis of bacterial meningitis score

validation studies »

Arch Dis Child. (2012) 97(9):799-805.

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Thank you

Prof. Alain Gervaix