2. Meningitis
• Infection and inflammation of the meninges
surrounding the brain by direct inoculation or
hematogenous spread.
3. • Epidemiology:
• can be caused by bacteria, viruses, or, rarely,
fungi.
• Viral meningitis is caused principally by
entero-viruses, including coxsackieviruses,
echoviruses, and, in unvaccinated individuals,
polioviruses.
Meningitis
4. • The organisms commonly causing bacterial meningitis :
S. pneumoniae , N. meningitidis and H. influenzae
type b .
• Incidence of H. influenzae type b meningitis has
decreased dramatically as a result of immunization.
the most frequent pathogens varied according to age
as follows:
• 1 month and <3 months—GBS (39%), gram-negative
bacilli (32%), S. pneumoniae (14%), N. meningitidis
(12%).
• ≥3 months and <3 years—S. pneumoniae (45%), N.
meningitidis (34%), GBS (11%), gram-negative bacilli
(9%).
• ≥3 years and <10 years—S. pneumoniae (47%), N.
meningitidis (32%).
• ≥10 years and <19 years—N. meningitidis (55%).
Meningitis
5. • Clinical manifestations: Preceding
upper respiratory tract symptoms are
common.
• Rapid onset is typical of S. pneumoniae and N.
meningitidis.
• Indications of meningeal inflammation include
headache, irritability, nausea, nuchal rigidity,
lethargy, photophobia, and vomiting.
• Fever usually is present.
Meningitis
6. • Kernig and Brudzinski signs of meningeal
irritation usually are positive in children older
than 12 months of age.
• In young infants, signs of meningeal
inflammation may be minimal with only
irritability, restlessness, depressed mental
status, and poor feeding.
Clinical manifestations
7. • Focal neurologic signs, seizures, arthralgia,
myalgia, petechial or purpuric lesions, sepsis,
shock, and coma may occur.
• Increased intracranial pressure is reflected in
complaints of headache, diplopia, and vomiting.
• A bulging fontanel may be present in infants.
• Ptosis, sixth nerve palsy , bradycardia with
hypertension, and apnea are signs of increased
intracranial pressure with brain herniation.
• Papilledema is uncommon, unless there is
occlusion of the venous sinuses, subdural
empyema, or brain abscess.
Clinical manifestations
8. • Neurologic sequelae include focal deficits,
seizures, hearing loss, and vision impairment.
• The most common permanent neurologic
sequel is hearing loss.
Complications
10. Diagnosis
Cerebrospinal Fluid Evaluation (CSF)
Normal Bacterial Viral Tuberculosis
WBC per mL 0–5 (allow up
to 30 in
neonates)
100–100,000 50–1,000 100 s
Glucose
(mg/dL)
45–65 Low Normal Low
Protein
(mg/dL)
20–45 High Slightly
increased
High
Gram stain Negative Positive Negative Negative
Meningitis
11. Treatment
• In neonates, initiate ampicillin plus
cefotaxime.
• Cefotaxime will treat GBS and gram-negative
enterics and penetrates the CSF.
• Ampicillin is mainly used for its effectiveness
against Listeria monocytogenes.
Meningitis
12. • In infants and children outside of the neonatal
age group, third-generation cephalosporin &
Vancomycin
• Third-generation cephalosporin is generally used
empirically, as it treats pathogens most likely
recovered at this age, including S. pneumoniae,
N. meningitidis & H. influenzae type b .
• Vancomycin is added for resistant S.
pneumoniae.
Treatment
Meningitis
13. • Duration of treatment is 10 to 14 days for S.
pneumoniae, 5 to 7 days for N. meningitidis, and
7 to 10 days for H. influenzae.
• Dexamethasone shown to decrease hearing loss
in those with meningitis due to H. influenzae type
b (given before or concurrently with first dose of
antibiotics).
• Antibiotic prophylaxis of close contacts to those
with meningococcal meningitis and H. influenzae
type b meningitis is indicated.
Treatment
Meningitis