• Initial Symptoms in Patients with Meningitis
90 %
90 %
85 %
Altered sensorium
>80 %
Kernig's Brudzinski's sign
50 %
35 %
30 %
Meningitis: CSF profile
DIAGNOSIS - Cerebrospinal Fluid Examination
• The CSF in cases of acute bacterial meningitis often
demonstrates a purulent (cloudy) appearance and contains
large numbers of neutrophils (5,000 to 10,000 per cubic
millimeter of CSF). In addition, the protein is usually
elevated and the sugar decreased. A definitive diagnosis of
pyogenic meningitis depends on the demonstration of
bacteria with a gram stain and/or subsequent culture.
Elevated protein
Decreased sugar
Positive gram
DIAGNOSIS - Cerebrospinal Fluid Examination
• In cases of granulomatous and lymphocytic meningitis , the
CSF is, in general, not cloudy and the cellular infiltrate
consists of lymphocytes, although the CSF may contain
neutrophils in the early stages. As in pyogenic meningitis,
the CSF protein and sugar are increased and reduced,
Granulomatous &
Viral Meningitis
Elevated protein
Decreased sugar
Negative gram
Meningitis: Treatment
• The initial management of a patient with presumed bacterial
meningitis includes performance of a lumbar puncture to determine
whether the CSF formula is consistent with that diagnosis
• If purulent meningitis is present, institution of antimicrobial therapy
should be based on the results of Gram staining or rapid bacterial
antigen tests.
• However, if no etiologic agent can be identified by these means or if
performance of the lumbar puncture is delayed (i.e., longer than 90
to 120 minutes), institution of empirical antimicrobial therapy should
be based on the patient's age and underlying disease status.
Recommended Antimicrobial Therapy for
Acute Bacterial Meningitis Based on the
Presumptive Pathogen Identified by
Positive Gram Stain or Bacterial Antigen Test
• Haemophilus influenzae type B
3rd-gen cephalosporin
• Neisseria meningitidis
Penicillin G or ampicillin
• Streptococcus pneumoniae
Vancomycin plus a
3rd-gen cephalosporin
• Listeria monocytogenes
Ampicillin or penicillin G
• Streptococcus agalactiae
Ampicillin or penicillin G
• Escherichia coli
3rd-gen cephalosporin
Empirical Therapy for Purulent
0-4 wk
Ampicillin plus cefotaxime;
or ampicillin plus an aminoglycoside
4-12 wk
Ampicillin plus a third-gen cephalosporin
3 mo to 18 yr
Third-generation cephalosporin ;
or ampicillin plus chloramphenicol
18-50 yr
Third-generation cephalosporin
>50 yr
Ampicillin plus a third-gen cephalosporin
Empirical Therapy for Purulent
• Immunocompromised
Vancomycin + ampicillin + ceftazidime
• Basilar skull fracture
Third-generation cephalosporin
• Head trauma
Vancomycin plus ceftazidime
• Postneurosurgery
Vancomycin plus ceftazidime
• Cerebrospinal fluid shunt
Vancomycin plus ceftazidime
• The duration of antimicrobial therapy in patients with bacterial
meningitis has been 10 to 14 days for cases of nonmeningococcal
meningitis. Meningococcal meningitis can be treated for 7 days with
intravenous penicillin.
Therapy for Viral Meningitis
• Treatment of acute viral encephalitis and meningitis (except
herpes) is directed at symptom relief, supportive care, and
prevention and management of complications.
• Although seizures sometimes complicate encephalitis,
prophylactic anticonvulsants are not routinely recommended.
• If seizures develop, they can usually be managed with
phenytoin and phenobarbital.
• Steroids should probably generally be avoided in the treatment
of encephalitis because of their inhibitory effects on host
immune responses.
• Full recovery from viral meningitis usually occurs within
1 to 2 weeks of onset
Therapy for Meningitis
• In patients who present with focal neurologic findings or who
have papilledema and bacterial meningitis is suspected, a CT
scan of the head should be performed before lumbar puncture to
rule out the presence of an intracranial mass lesion because of
the potential risk of herniation.
• After obtaining blood cultures, the emergency empirical
antimicrobial therapy should be initiated before sending the
patient to the CT scanner.
• Once the infecting meningeal pathogen is isolated and
susceptibility testing known, antimicrobial therapy can be
modified for optimal treatment.
Therapy for Meningitis
• In addition, certain patients should receive adjunctive
dexamethasone therapy when presenting with suspected or
proven bacterial meningitis .
• Currently, data support the routine use of adjunctive
dexamethasone therapy (0.15mg/kg every 6 hours for 2 to 4
days) in infants and children with meningitis caused by
H. influenzae type B
• In adults or in patients with meningitis caused by other bacteria,
dexamethasone is not routinely recommended, although some
authors recommend its use in all patients with presumed
bacterial meningitis.