Meningitis Recap & The role of steroids in Bacterial Meningitis...

We recently discussed meningitis and an approach to the work-up and management of patients with meningitis. Here are a few key points:

Major causes of Community-Acquired bacterial meningitis in adults in developed nations: Streptococcus pneumonia, Neisseria meningitidis. In those >50 years, or those with immune deficiencies, consider Listeria monocytogenes.

Mortality is higher for S. pneumonia meningitis (9-26%) versus N. meningitidis (3-13%).

How good are our physical exam approaches?

Kernig’s sign: patient laying supine, with hips flexed >90; extension of knees from this position elicits resistance or pain in low back or posterior thigh

Brudzinksi’s sign: passive neck flexion in the supine patient results in flexion of the knees and hips

NOTE: both of these signs are specific, but both have a low sensitivity! These two tests were initially developed to assess patients with late, end-stage meningitis (i.e. caused by TB)

·          

        Jolt Accentuation of headache: patient turns their head horizontally at a frequency of 2-3 rotations per second. Worsening heachache = +ve sign, sensitivity 97%, specificity 60%

o NOTE: evaluated in a single study of 34 patients!

When to order a CT head prior to performing a Lumbar Puncture (LP):

·          CT head: may demonstrate structural abnormalities (ICH, brain abscess, tumor); risk of herniation in performing an LP when the patient has a mass/increased ICP

o   Evidence; those without findings on hx or physical to suggest increase ICP, can safely undergo an LP without a prior head CT

o   2004 IDSA Guidelines: A CT head is indicated before LP if there is 1 or more of:

§  Age >60

§  History of CNS disease, 

§  New onset seizures within 1 week

§  Focal neurological deficits/abnormalities

§  Papillodema

§  Obtunded/AMS

§  Immuno-compromised state (i.e. HIV infection, immune-suppressive therapy, solid organ/hematopoietic stem cell transplantation)

CT and/or performing a Lumbar Puncture: Should NOT delay empiric antibiotic therapy

• Ensure the patient is hemodynamically stable, protecting their airway, etc. 
• Draw blood cultures and administer empiric antibiotics, consider dexamethasone 0.15 mg/kg IV q6h (see Cochrane review link below)
• Cochrane Review (2010): summarized that the meta-analysis, although not demonstrating evidence of optimal strength, they recommended a 4 day regimen of dexamethasone (0.6 mg/kg daily) given before or with the first dose of antibiotics. This may reduce sequelae (i.e. hearing loss)

• Droplet precautions: H. influenza & N. meningiditis x24h of Abx
• Empiric Antibiotics “CVA”

o   Give Dexamethasone for acute bacterial meningitis 15-20 minutes before 1^st dose of Antiobiotics if suspicion for S. pneumonia (0.15 mg/kg or 10 mg IV q6h x4 days)à ? reduce mortality, ? reduce sequelae (i.e. hearing loss)

o   Ceftriaxone 2g IV q12h (or Cefotaxmine)

o   Vancomycin 1-1.5 g IV q12h: to cover resistant S. pneumonia (penicillin-resistant Pneumococci coverage until sensitivities are known!)

o   Ampicilin 2g IV q4h if: age >50, immune-compromised (to cover Listeria)

NOTE: If concern for HSV encephalitis, add acyclovir 10 mg/kg IV q8h

NOTE: IF culture comes back with N. meningididisà prophylaxis to household and those who have had intimate contact; Healthcare workers should receive prophylaxis if they have had direct contact with respiratory secretions.

Resources: Papers & Links

Infectious Disease Society of America (IDSA)- Guidelines on Meningitis

Corticosteroids for acute bacterial meningitis (Review). Cochrane Review (2010).

JAMA