Diagnostic des mningites communautaires

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Diagnostic des méningites communautaires

• Bruno Hoen
• 4ème Journée Maurice Rapin
• 16 octobre 2003

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Les étapes du diagnostic des méningites
communautaires

• Diagnostic positif de méningite
• Place de l'imagerie dans la démarche diagnostique
  initiale
• Diagnostic étiologique (bactérie vs. virus)

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Les étapes du diagnostic des méningites
communautaires

• Diagnostic positif de méningite
• Place de l'imagerie dans la démarche diagnostique
  initiale
• Diagnostic étiologique (bactérie vs. virus)

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The Diagnostic Accuracy of Kernigs Sign,
Brudzinskis Sign, and Nuchal Rigidity in Adults
with Suspected Meningitis

• To determine the diagnostic accuracy of Kernigs,
  Brudzinskis, and nuchal rigidity, 297 adults
  with suspected meningitis were prospectively
  evaluated for the presence of these signs before
  LP. 80 had meningitis (gt 5 cells/mm3)
• Kernig's, Brudzinski's
• Se 5
• Sp 95
• PPV 27
• NPV 72
• Nuchal rigidity
• Se 30
• Sp 68
• PPV 26
• NPV 73

Thomas, CID 2002
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The Diagnostic Accuracy of Kernigs Sign,
Brudzinskis Sign, and Nuchal Rigidity in Adults
with Suspected Meningitis

• Diagnostic accuracy of Kernig's sign,
  Brudzinski's sign, and nuchal rigidity in the 29
  patients with ? 100 WBCs/mm3
• Kernig's, Brudzinski's
• Se 9
• Sp 96
• PPV 18
• NPV 91
• Nuchal rigidity
• Se 52
• Sp 71
• PPV 16
• NPV 93

Thomas, CID 2002
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Les étapes du diagnostic des méningites
communautaires

• Diagnostic positif de méningite
• Place de l'imagerie dans la démarche diagnostique
  initiale
• Diagnostic étiologique (bactérie vs. virus)

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Conférence de consensus 1996

• A la prise en charge initiale d'une méningite
  purulente, les indications d'imagerie cérébrale
  doivent rester très limitées.
• L'urgence est à la mise en route de
  l'antibiothérapie qui doit être précédée d'une
  ponction lombaire.
• Les risques de la PL sont faibles et de loin
  inférieurs à ceux de la méningite. La réalisation
  d'un scanner avant la PL expose au risque de
  retarder la mise en route de l'abthérapie, a un
  rendement diagnostique faible et a en fait peu
  d'influence sur la prise en charge thérapeutique
  initiale.
• Pour toutes ces raisons, la PL doit précéder le
  scanner, même en cas de coma. Ce n'est que devant
  des signes neurologiques focalisés, faisant
  évoquer un autre diagnostic ou craindre une
  complication intracrânienne, que la démar-che
  diagnostique doit être modifiée. Le scanner
  suffit pour le diagnostic de la plupart des
  complications intracrâniennes.

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CT scan of the head before LP in adults with
suspected meningitis
Hasbun, N Engl J Med 2001
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CT scan of the head before LP in adults with
suspected meningitis

• characteristics
• gt 60 years
• immunosuppression
• history of a CNS disease
• seizure within 1 week before presentation
• and the following abnormalities
• abnormal level of consciousness
• inability to answer 2 consecutive questions
  correctly
• inability to follow two consecutive commands
  correctly
• gaze palsy
• abnormal visual fields,
• facial palsy,
• arm drift, leg drift,
• abnormal language.

Hasbun, N Engl J Med 2001
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CT scan of the head before LP in adults with
suspected meningitis

• Negative predictive value of clinical
  examination 97 .
• Of the 3 misclassified patients, only one had a
  mild mass effect on CT, and all three
  subsequently underwent LP, with no evidence of
  brain herniation one week later.
• In adults with suspected meningitis, clinical
  features can be used to identify those who are
  unlikely to have abnormal findings on CT of the
  head.

Hasbun, N Engl J Med 2001
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CT scan of the head before LP in adults with
suspected meningitis

• 75 consecutive cases of pneumococcal meningitis
• Cerebral herniation occurred in 10 patients and
  could not be predicted by
• Focal signs
• 3/10 vs 17/65, p1
• Seizures within past 24 hours
• 3/10 vs. 11/65, p0.38
• GCS lt 12
• 7/10 vs. 43/65, p1
• CT scan abnormalities
• 2/10 vs 27/65, p0.3

Kastenbauer, N Engl J Med 2002
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Timing of antibiotic administration and mortality
in adult acute bacterial meningitis

• Retrospective review of 123 cases of AABM
• Does increased door-to-antibiotic time (DAT)
  increase mortality?
• 2 independant predictors of mortality
• Severely impaired mental status (OR 12.4,
  p0.001)
• DAT gt 6 h (OR 9.7, p 0.002)
• Does CT scan before LP increase DAT?
• AB / CT/ LP was associated with the lowest DAT
  (2.5 h)
• CT / LP / AB was associated with the highest DAT
  (12 h).

Proulx, ICAAC 2003, abstract L-614
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(No Transcript)
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Les étapes du diagnostic des méningites
communautaires

• Diagnostic positif de méningite
• Place de l'imagerie dans la démarche diagnostique
  initiale
• Diagnostic étiologique (bactérie vs. virus)

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Les caractéristiques du LCR pour le diagnostic
étiologique des méningites
Hoen, Eur J Clin Microbiol Infect Dis 1995
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Quelle place pour la détection dantigènes
bactériens dans le LCR ?

• Lack of sensitivity of the latex agglutination
  test to detect bacterial antigen in the CSF of
  patients with culture-negative meningitis
  (Tarafdar CID 2001)
• Sensitivity 7
• Rapid bacterial antigen detection is not
  clinically helpful (Perkins, J Clin Microbiol
  1995)
• Retrospective analysis of positive CSF latex
  antigen tests
• Specificity 71
• GSF Gram stain and/or culture were positive in
  all cases

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Modèle mathématiqued'aide au diagnostic

• Le modèle
• établi sur 500 cas de méningites aiguës
  primitives
• pABM 1/(1e-L), où
• L 32,13 x 10-4 x nb PNN LCR (106 /l) 2,365
  x protéinorachie (g/l) 0,6143 x glycémie
  (mmol/l) 0, 2086 x nb de GB sanguins (109/l)
  11
• Ses performances pour la valeur de pABM 0,1
• Sensibilité 97 VPN 99
• Spécificité 82 VPP 85
• AUCROC 0,98

Hoen, Eur J Clin Microbiol Infect Dis 1995
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Prospective Validation of a Diagnosis Model as an
Aid to Therapeutic Decision in Acute Meningitis

• 109 consecutive patients with acute meningitis
  and negative cerebrospinal fluid Gram stain.
• pABM was computed before therapeutic decision and
  diagnosis was established in 3 steps
• Clinical before pABM computation, bacterial,
  viral, uncertain
• Computed viral if pABMlt0.1, bacterial otherwise
• Definite bacterial positive cerebrospinal fluid
  culture viral negative cerebrospinal fluid
  culture, no other aetiology and no
  treatmentuncertain fitting neither of the
  first two

Baty, Eur J Clin Microbiol Infect Dis 2000
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Prospective Validation of a Diagnosis Model as an
Aid to Therapeutic Decision in Acute Meningitis

• Computed diagnoses were
• viral in 78 of the 80 definite viral cases
• bacterial in 4 of the 5 definite bacterial cases.
  
• Negative predictive value of the model was 98.7
• Clinical diagnosis was uncertain in 22 cases
• 15 of which were definite viral cases
• in all of these 15 cases, computed diagnosis was
  viral, leading the physician to refrain from
  starting antibiotics in all of them.
• The model is reliable and helps physicians
  identify patients in whom antibiotics can be
  avoided safely.

Baty et al. Eur J Clin Microbiol Infect Dis 2000
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Validation of a diagnosis model for
differentiating bacterial from viral meningitis
in infants and children under 3.5 years of age
Distribution of the causative microorganisms in
103 cases of acute meningitis
Jaeger et al. Eur J Clin Microbiol Infect Dis 2000
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Validation of a diagnosis model for
differentiating bacterial from viral meningitis
in infants and children under 3.5 years of age
Performance of the model for different cut-off
points of the probability of bacterial meningitis
(pABM).
Jaeger et al. Eur J Clin Microbiol Infect Dis 2000
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Measurement of procalcitonin levels in children
with bacterial or viral meningitis

• CRP 2 patients with bacterial meningitis and 5
  with viral meningitis had overlapping CRP values
  of 2050 mg/l.
• PCT gt 5 mg/l, for diagnosis of bacterial
  meningitis
• sensitivity 94,
• specificity 100.

Gendrel, CID 1997
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High Sensitivity and Specificity of Serum
Procalcitonin Levels in Adults withBacterial
Meningitis

• Prospective study of 105 consecutive adult
  patients admitted to an emergency care unit for
  suspicion of acute meningitis.

Viallon, CID 1999
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High Sensitivity and Specificity of Serum
Procalcitonin Levels in Adults withBacterial
Meningitis
Viallon et al., Clin Iinfect Dis 1999
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Damien, 15 ans, collégien

• 1 octobre 2003 syndrome méningé aigu fébrile
  évoluant depuis 8 heures au moment de la PL pas
  de purpura
• PL LCR clair, 185 GB/mm3, 70 PNN, P 0.7 g/l, G
  3.1 mmol/l
• GB 15000/mm3, 91 PNN, CRP 15 mg/l
• Procalcitonine 5 ng/ml
• pABMhoen 0,06
• Traitement par Ceftriaxone, en attendant PCR/LCR
• J5 cholécystite aiguë
• J7 diagnostic étiologique
• Recherche virus gorge et selles positive à
  enterovirus.
• PCR méningocoque négative

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Evaluation of a Rapid PCR Assay for Diagnosis of
Meningococcal Meningitis

• 281 patients with suspected bacterial meningitis
• 38 met the criteria for meningococcal meningitis
• clinical signs and symptoms of meningitis, and
• pleocytosis (gt 10 cells/mm3), and
• positive CSF or blood culture for N.
  meningitidis, or
• CSF Gram stain positive with Gram-negative
  diplococci, or
• positive PCR assay of CSF for meningococcal IS
  1106, confirmed by a second test
• 65 had other bacteria identified
• Streptococcus pneumoniae n 45
• 178 had no bacteria identified
• PCR assay was performed in all 281 CSF samples

Richardson, J Clin Microbiol 2003
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Evaluation of a Rapid PCR Assay for Diagnosis of
Meningococcal Meningitis

• Comparison of accuracy of diagnostic methods in
  the 38 cases of meningococcal meningitis
• PCR was negative in all other CSF samples
• Duration of PCR assay 2 hours.

Richardson, J Clin Microbiol 2003
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Use of universal PCR on CSF to diagnose bacterial
meningitis in culture-negative patients

• 97 cases of suspected bacterial meningitis, with
  negative CSF culture
• All negative controls negative by PCR
• All positive controls positive by PCR

Margall Coscojuela, Eur J Clin Microbiol Infect
Dis 2002
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Application of PCR for various neurotropic
viruses on the diagnosis of viral meningitis

• CSF samples were collected from 73 children
  suspected of having meningitis from November 1991
  to December 1994.
• The samples were examined for infectious viruses
  by cell culture and for viral genomes by multiple
  PCR.
• 45 diagnoses of aseptic meningitis positive PCR
  results for
• Enterovirus 25
• Mumps virus 14
• Cytomegalovirus 1
• Varicella-zoster virus 1
• Diagnosis sensitivity
• PCR alone 91.1
• PCR conventional virological methods 97.8.

Hosoya, J Clin Virol 1998
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Evaluation of a rapid real-time RT-PCR assay for
detection of enterovirus RNA in CSF specimens

• 251 CSF specimens with a differential diagnosis
  including viral meningitis from 03/00 to 11/01.

Sensitivity 57.4 72.6
Verstrepen, J Clin Virol 2002
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Impact of rapid PCR results on management of
pediatric patients with enteroviral meningitis

• CSF specimens from 113 patients with suspected EV
  meningitis were submitted for EV PCR
• 50 of 113 (44) were positive.
• 17 of 50 (34) had results available in lt24 h
• 33 of 50 (66) had results available in gt24 h.
• Patients with EV-positive results reported lt24 h
  after specimen collection had
• 20 h less of antibiotic use (P 0.006) and
• 2798 USD less in hospital charges (P 0.001)

Robinson, Pediatr Infect Dis J 2002
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Syndrome méningé fébrile sans purpura
Existe-t-il des signes neurologiques en foyer ?