Sunday, October 28, 2007

Meningitis by Dr. Nadeem Khawer

MENINGITIS
NADEEM KHAWAR

Etiology
Viral
Bacterial
Fungal
Parasitic

Bacterial Meningitis
Nasopharyngeal Carriage
H.Influenzae
Meningococcus
Pnemococcus
Maternal Vaginal Flora
Gram negative organisms < 2 months



Multicentre Meningitis Study Data: Oct. 01 to Sept.05
H.Influenzae 70
N.Meningitidis 16
S.Pneumoniae 55
No Growth 71
Total 212
Unpublished data/AKUH
Karachi & Hyderabad
Route of infection
Ø Inhalation --- Bacterimia --- CNS

Ø Direct
Ø Anatomical defects
Ø Clinical Features
Ø Non specific (infancy)
Ø Fever , irritability,vomiting,anorexia
Ø Specific (children)
Ø Neck rigidity
Ø Signs of raised intra cranial pressure
Ø Seizures
Ø Focal CNS signs
Remember
1. Neck stiffness may not be present in infants and young children
2. Absence of neck stiffness does not rule out meningitis in infants and young children
3. Always consider meningitis in any child with fever and neurological signs
4. Always admit the child with suspected meningitis
5. Diagnosis
6. High index of suspicion in non specific cases
7. Straight forward in specific cases
8. Lumber puncture and CSF analysis confirms the diagnosis
Lumber Puncture
lIndications
–Suspected meningitis
–Not always required in ‘clear cut ‘ cases
lDisadvantage : causative organism missed. esp.TBM in our setup
lAdvantage :invasive procedure,potential complications
lContra indications
Comatose child or with focal CNS signs
Papiledema
Hemodynamically unstable
Bleeding disorder
Local infection
Normal CSF values
Cells: < 5/mm
Protein : 25 to 45 mg /dl
Glucose : 2/3rd of plasma glucose
Color: clear fluid
Other CSF tests
Gram stain
Culture
Rapid antigen tests
Latex particle agglutination
Counter immune electrophoresis

Other Investigations
Ø Blood count (CBC)
Ø Blood culture
Ø Electrolytes
Ø Glucose

Ø CT brain
Differential Diagnosis
v Cerebral Malaria
v Tuberculous Meningitis
v Herpes Encephalitis
v Viral Meningoencephalitis
v Brain abscess
v Leukemia
v Collagen Disorders

Treatment
ü Hospitalize
ü Supportive care
§ Nutrition
§ Fluid balance
§ Respiratory
§ Seizures/ raised ICP
ü Specific
ü Antibiotics
ü Always parenteral preferably IV
ü 3rd generation cephalosporins alone may be sufficient but expensive.
ü Ampicillin (200mg/kg/24hrs) + Chloremphenicol (100mg/kg/24 hrs) suitable & affordable regime

ü Third Generation Cephalosporins
ü Ceftrioxone (Rocephin) :100 mg/kg/24 hrs advantage: OD dosage
ü Cefotaxime (Claforan) :200 mg /kg/24 hrs needs TID regime
ü Ceftazidime (Fortum):150 mg/kg/24 hrs
ü esp. for pseudomonas cover

ü Vancomycin for resistance Pnemococcus


Antibiotic Resistance
Pnemococcus
o Penicillin 25 to 50 %
o 3rd gen.cephalosporins 5 to 10 %
H Influenzae
o Penicillin 30 to 40 %
Duration of Antibiotics
lGeneral rule : 10 days or 72 hours after defervescence
lMeningococcus
–7 days
lH Influenzae
–10 days
lPnemococcus
–14 days
Steroid Use
H.Influenzae type b
Prevent sensorineural deafness

0.15 mg/kg/dose qid x 2 days
1 to 2 hours prior to antibiotic

Complications
Seizures
Cranial nerve palsies
Hydrocephalus
Cerebral infarction/ Stroke
Dural venous sinuses thrombosis
Subdural effusions/ empyema
SIADH
DIC
Persistent Fever
v Intercurrent viral infection
v Nosocomial bacterial infection
v Partially treated meningitis(dose/ resistance)
v Drug reaction
v Thrombophlebitis
v Malaria
Prevention
· Vaccination

· Antibiotic Prophylaxis of contacts
§ Meningococcus
§ H. Influenzae type b
§ Rifampicin x 2 days

Thank you

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