Transcript Acute Bacterial Meningitis

DIAGNOSIS AND
MANAGEMENT OF
MENINGITIS
Created by Stephanie Singson
Updated by Saahir Khan
Objectives
Learn how to classify meningitis into
bacterial, aseptic, or
fungal/mycobacterial categories.
 Learn diagnostic workup for
meningitis
 Learn empiric and targeted therapy
for meningitis

Classify Patient by Presentation

Bacterial Meningitis
 Triad
of fever, nuchal rigidity, change in mental status
 Rapid progression to coma and death

Aseptic Meningitis/Encephalitis
 Less
febrile, less acute, headache with flu-like symptoms
 May have focal neurological symptoms (encephalitis)

Fungal/Mycobacterial Meningitis
 Indolent
onset, usually immunosuppressed
 May have increased ICP (vomiting, double vision)
Tunkel et al. IDSA: Bacterial Meningitis. Clinical Infectious Disease. 2004.
Classify Patient by Physical Exam

Bacterial Meningitis
Kernig and Brudzinski signs are specific but insensitive
 Petechial rash may indicate meningococcemia


Aseptic Meningitis/Encephalitis


May have focal temporal signs (HSV) or paralysis (West-Nile)
Fungal/Mycobacterial Meningitis
Respiratory signs may indicate TB or cocci
 Increased ICP (papilledema) may indicate TB or crypto

LeBlond, RF et al. DeGowin’s Diagnostic Examination. 10th Edition. McGraw-Hill Education.
Diagnose Patient: Approach
Tunkel et al. IDSA: Bacterial Meningitis. Clinical Infectious Disease. 2004.
Diagnose Patient: Lumbar Puncture
Etiology
Normal
Bacterial
Viral/Syphilis
Fungal/TB
Appearance
Clear
Cloudy
Clear
Cloudy
OP (cm H2O)
< 20
> 25
20-25
> 25
WBC Count
<5
> 100
(>90% PMN)
10-500
(>50% lymph)
10-500
(>50% lymph)
CSF/Serum Glucose
> 0.6
< 0.4
> 0.6
< 0.4
Protein (mg/dL)
< 45
> 50
> 50
> 50
Gram Stain
Culture
S. pneumo Ag
HSV, WNV PCR
CMV, VZV PCR
Enterovirus PCR
VDRL
Crypto Ag
Cocci, Toxo Ab
AFB + Culture
Fungal Culture
CXR
Further Testing
(if indicated)
Medscape
Treat Patient: Bacterial Meningitis

Initial Therapy

Strep pneumo, Neisseria meningitides, H. influenza


Listeria monocytogenes (age>50 or immunocompromise)


Add ampicillin
MRSA, Pseudomonas (post-neurosurgery or skull trauma)


Treat with ceftriaxone and vancomycin (better strep coverage)
Switch ceftriaxone to cefepime or meropenem
Adjunctive Measures
Add dexamethasone (reduces death by pneumococcus)
 Droplet isolation (until meningococcus ruled out)


Target therapy to CSF gram stain and culture
Treat Patient: Aseptic Meningoencephalitis

Initial Therapy
 HSV
in community, VZV if zoster, CMV post-transplant
 Add
acyclovir (HSV, VZV) or ganciclovir (CMV)
 Syphilis
 Add

if STI risk or immunocompromise
penicillin
Adjunctive Measures
 Consider
UpToDate
IFN, IVIG for refractory WNV (minimal data)
Treat Patient: Fungal/TB Meningitis

Targeted Therapy
 IV
amphotericin B + flucytosine for crypto
 Sulfadiazine + pyrimethamine for toxo
 Fluconazole for cocci (+ intrathecal ampho if severe)
 RIPE for at least 1 year for TB

Adjunctive Measures
 Consider
serial LP or ventricular drain for elevated ICP
 Add dexamethasone for TB (reduces mortality)
 Airborne isolation for active TB if respiratory symptoms
Galgiani et al. IDSA: Coccidiomycosis. Clinical Infectious Disease. 2005.
UpToDate
Case Example


Mr. B is a 70-year-old man with history of CAD and
HTN brought by family from home to the ED for
fever and confusion that started this morning.
On presentation, vitals were T 38.3C (101F), BP
96/52, HR 101/min, RR 20/min. On exam, mental
status was drowsy, patient was oriented only to
person, and neurological exam was non-focal.
How would you manage Mr. B?
Droplet isolation. Non-contrast head CT.
Indication: Abnormal level of consciousness
Result: Negative for bleed or acute abnormality
Draw blood cultures. Perform LP.
Result:
Opening pressure 300 mmH2O
Leukocyte count 600/uL (80% neutrophils, 20% lymphocytes)
Glucose level 30mg/dL
Protein level 350mg/dL
Gram stain negative
Administer empiric therapy:
Dexamethasone, Vancomycin, Ceftriaxone, Ampicillin (age> 50)
Await culture results to target antibiotic regimen.
Summary


Meningitis can be divided into bacterial, aseptic (viral
or syphilis), and fungal/mycobacterial categories
Lumbar puncture is primary tool for diagnosis
 Preceded

by imaging if risk for CNS pathology
Treatment is initially empiric, then targeted to pathogen
 Empiric
vancomycin/ceftriaxone/ampicillin/dexamethasone
for community-acquired bacterial meningitis and acyclovir
for aseptic meningoencephalitis