Meningitis B - Protecting your baby against meningitis and ...
Meningitis
-
Upload
the-medical-post -
Category
Health & Medicine
-
view
1.992 -
download
0
Transcript of Meningitis
Meningitis
Dr. Kalpana MallaMD Pediatrics
Manipal Teaching Hospital
Download more documents and slide shows on The Medical Post [ www.themedicalpost.net ]
Definitions
• Meningitis : inflammation of the lepto-meninges covering the brain and the spinal cord
• Encephalitis : inflammation of brain parenchyma, with cerebral dysfunction.
• Encephalopathy : cerebral dysfunction , due to toxins, metabolites, poisons etc , affecting neurons without inflammatory response.
Classification:
1) Viral2) Bacterial 3) Tubercular4) Others: Parasitic: malarial, amebic, toxoplamosis
Fungal: candiadiasis, cryptococcal, histoplasmosis
Bacterial Meningitis• Causes:• 0-2months: - Group B & D streptococcus - Gram neg enteric bacilli - E.coli, Klebsiella pneumoniae - L. monocytogenes - Sometimes H influenza2mo-5years: - H. influenzae typeb - Strep. Pneumoniae
- N. meningitidis>5 years: - S. pnemoniae - N. meningitidis
May spread to the meninges either Hematogenously, or by contiguous spreadPredisposing factors include:1) Septicemia2) Septic foci in skin, lungs, bones3) Trauma ie. Fracture base of the skull4) Neural tube defects5) Suppurative ear, mastoid infec
Etiology • N meningitis – epidemics• S. Pneumoniae – epidemics• H influenza – uncommon after 3 years,
incidence decreased after Hib vaccine.• Less common – staph – seen in vp shunt• Less common – E. coli, pseudo, proteus –
neonates, immuno compromised.
PATHOGENESIS Host : • Young age , close contact with bacteria , altered
immunoglobulin response, defect of complement system – C5-8 – recurrent meningococcal inf.,
• Defect of properdin system : meningococcal inf.,• Splenic dysfunction : pnemococcal and H influenza• T lymphocyte defect : L monocytogens• Altered mucocutaneous barrier : cribiform plate
damage, middle ear inf. – pneumococcal• Lumbosacral myelocele : staph and gram neg. enteric
bacilli
BACTERIAL COLONISATION OF NASOPHARYNX with pathogenic bacteria(eg N meningitis and H influenza attach to mucosal surface by pilli and enter circulation)
Blood stream Invasion / Bacteremia
CNS PENETRATION
DIRECT INVASION
THROUGH choroid plexus Lat ventricle, meninges
BLOOD CYTOKININE RELEASE
Intravascular Volume decreases
↓CSF flow
EndothelialLeukocyte activation
Release ofSecondary mediators
Bacteria rapidly multiply As CSF conc. Of complement And antibody LOW
Complement system activation CSF cytokine release
BBB disturbedPMN STIMULATION
FREE RADICAL RELEASE
↓CSF flow
Meningeal inflammation
Brain edema
Brain damage
Clinical features:
• Constitutional symptoms : Lethargy, irritability , anorexia, vomiting, fever – mild, high, hypothermia in infants, Poor
feeding, Arthralgia, myalgia
Meningeal features: Neck rigidity, kernig’s, brudzinski’s sign. These may be absent in infants, Neck pain,
Clinical features:
• Features of raised ICP: - HTN with bradycardia, - Apnea or hyperventilation, - Head ache , photophobia, - Vomiting- projectile - Buldging AF if open, 6th nerve palsy - Hypertonia, extensor plantars - Decorticate/decerebrate posturing - Papilledema
Raised ICP due to:
1) Cell death (cytotoxic cerebral edema)2) Cytokine induced increased vascular
permeability(vasogenic cerebral edema)3) Increased hydrostatic pressure after
obstructed reabsorption of CSF in the villus or obstruction of the flow of fluid from the ventricle
4) SIADH
Clinical features:
Features of parenchymal involvement: Altered sensorium, seizures, Coma and focal
neurological signs• Cutaneous features: erythamatous macular
rashes, petechiae
Clinical features:
• Extra CNS manifestations: Rashes, petechiae, athralgia, shock, DIC,
depending on etiology
In very young, immunocompromised, severely malnourished child signs of overt meningitis may be absent
Meningitis in neonates and infants
• Vacant stare, persistent vomiting, refusal to suck, poor tone, poor cry, shock, circulatory collapse, hypothermia/fever, convulsions, neurological signs.
• More risk if – premature, LBW, coplicated labour, PROM, maternal sepsis……
Signs:
• Neck rigidity• Kernig’s sign• Brudzinski’s sign• Bulged fontanelle• Sutural diastasis• Cranial n. palsies (oculomotor, abducens,
facial, auditory)• photophobia
Tubercular Meningitis• Most serious complication & fatal without Rx• Commonly affects children from 6mo- 4years
of age• Rapid progression occur in infants & young
children
TBM
• Pathogenesis:1) Rupture of subependymal tubercles – TB
bacilli in subarachnoid space2) Lymphohematogenous dissemination of
primary infection
First stage
• Over 1-2 weeks – 2-8 weeks• Stage of invasion/prodromal stage• Nonspecific and vague● Fever ● Headache● Irritability ● Drowsiness● Malaise ● Shrill cry 100% cure
Second stage - Stage of meningitis
• Over 1-2 wks• More abrupt• Lethargy - Projectile vomiting• Nuchal rigidity - Bulging frontanelle• Seizures - Cranial nerve palsies• Kernig/brudzinisky’s sign +• 25% mortality, 25 % sequelae
• Hypertonia• Cranil N palsies 3rd-7th • Ocular paralysis• Strabismus, nystagmus• Hemiplegia/quadriplegia• Semicoma/coma
Third stage - Stage of coma• Unconscious- Coma• Repeated convulsions • High fever: “terminal fever”• Severe neurological involvements – - Hemiplegia/paraplegia - Quadriplegia/ decerebrate rigidity - Decerebrate posturing - Opsithotonus - Deteriorating mental status• Deteroration of vital signs- Hypertension• 50% mortality • 50% cure but almost all have sequelae
Disabilities of TBM
• Blindness ● deafness● paraplegia /hemiplegia● squint ● MR● epilepsy ● CP● CN palsies ● Endocrine disturbances
INVESTIGATIONS
1)Lumbar puncture: should be done before any antibiotics started
precautions: C/I for an immediate LP : - EVIDENCE OF increased ICT ( other than
bulging fontanels). - Fundoscopy, to rule out papilloedema -
-infections overlying the site of puncture
-Relative C/I - Thrombocytopenia-Cardiopulmonary compromise & shock
LP• DO RBS 30 min before LP.• CHILD IN LATERAL POSITION with knee, hip, head
flexed.• Clean site L4-5, L3-4.• LP stilleted needle, with direction towards umblicus ,
perpendicular to spine.• Collect CSF – TUBE 1 – cell count, type• Tube 2 – C/S.• TUBE 3 – glucose, protein• Tube 4 – latex fixation tests• 0.5 to 1 ml each tube.
Investigations 2) Blood Culture: 3) Chest Roentogram4) S. electrolytes5) CBC, CRP6) Skin scraping for C/S7) Mantoux Test7) Serology: Latex agglutination, counter
current immunoelectrophoresis8) CT,MRI- for detection of hydrocephalus,
abcess, effusion, exudates, edema
Normal PYOGENIC VIRAL MYCOBACTERIAL
FUNGAL
GROSSCLEAR
TURBID CLEAR COBWEB CLEAR-TURBID
Pressure Mm H20
50-80
100-300 80-150 >80 >80
PYOGENIC VIRAL MYCOBACTERIAL
FUNGAL
SUGARMG/DL
>50(75% OF RBS
<40(<50% OF RBS)
N ( < 40 IN
MUMPS)
<50 <50
PROTEIN
MG/DL20-45
100-500 50-200 100-3000 25-500
PYOGENIC VIRAL MYCOBACTERIAL
FUNGAL
TOTAL CELL
<5
100-10,000 100 10-500 5-500
PREDOMINAT TYPE,>75%
Lympho
PMN lymphocytes
Lympho Monnuclear
PARTIALLY TREATED MENINGITIS
• Culture : sterile in 48 hrs• Sugar normalize by 48 hrs• Cells may increase initially, persistence of
neutrophil indicates poor response.• Protein : take longer time to normalize, thus
not good parameter for adequacy of treatment.
RAPID DIAGNOSTIC TESTS
• PCR – for diagnosis of infections ( herpes, TB, meningococci)
• Latex agglutination and ELISA- antigen antibody detection
• CSF C-RP, LDH, lactic acid – to differentiate pyogenic from non pyogenic.
ORGANISM ANTIBIOTIC DOSE DURATION
UNKNOWN
EMPERIC1)CEFTRIAXONE2)CEFOTAXIME3)AMPI/PENCILLIN G + CHRAMPHENi
100-150 MG/KGDAY4 LAC U/KG/DAY100 MG/KGDAY
10 DAYS
MENINGOCOCCUs
Pencillin G 3-4 lac U/KG/DAY
7DAYS
ORGANISM ANTIBIOTIC DOSE DURATION
Pneumococcus
Pencillin G or if resistance – Ceftriaxone plusVancomycin
40 MG/KG/D
10DAYS
Gram neg. Ceftriaxone/cefotaxime plus aminoglycogide
21DAYS
ORGANISM ANTIBIOTIC DOSE DURATION
Pseudomonas Ceftazidime 150 MG/KG/D
14-21DAYS
Staphylococci
Vancomycin 40 MG/KGDAY
28DAYS
H influenza CeftriaxoneCefotaxime
10-14 DAYS
2) Anti inflammatory therapy Dexamethasone: 0.15mg/kg/dose 6hrly for 2
daysFirst dose should be given prior to starting antibiotics
In case of TBM: prednisolone;4-6wks
STEROID THERAPY
• Rationale : to decrease cytokine related damage , esp . To 8th nerve .
• Decrease ICT• ESP. useful for children older than 6 weeks with
suspected H influenza.• Current recommendation : • Dexamethasone : 1-2 hr before first antibiotic dose• 0.15mg/kg/dose every 6 hrly for 2 days.
General Care
- Fluid and electrolytes homeostasis -Check for shock – fluid bolus NS
• NPO• Oral feeds if sensorium –ok• Care of oral cavity, eyes, bladder,bowel and skin• IF suspecting SIADH – give 2/3rd maintenance• Symptomatic Management: Paracetamol
Diazepam, Phenytoin, Phenobarbitone
Supportive care
Seizures • No role for prophylactic use of AED• For immediate control : lorazepam/diazepam, • Load on phenytion to reduce recurrence.• Phenytoin preferred than pheno as produces less
CNS depression and permits assessment of levels of consciousness.
Treatment of raised intracranial pressure• Head end elevation to 30 degree• Fluid – 2/3 rd maintaiance• Do not use hypotonic fluids• 20% mannitol• Frusemide• Acetazolamide• Glycerol
4) Treatment of complications: Shock: Volume expander, FFP,
Dopamine Subdural effusion: Aspiration
Hydrocephalus: Shunt Operation (VP)
Complications - immediate
• Seizure • Raised ICP• Stroke• Cerebral or Cerebellar herniation • Sub Dural Effusion• SIADH
• Ventriculitis• Brain abscess• Hydrocephalus• DIC• Cranial Nerve Palsy• Thrombosis of dural sinuses• Shock
CHRONIC –late
• Permanent brain damage with - CP,Mental retardation, - Epilepsy - Deafness - Blindness - Hemiplegia - Hydrocephalus• EHAVIOUR PROBLEMS
POOR PROGNOSIS
• SEIZURES THAT PERSIST after 4 days of illness and are difficult to treat
• Coma• CSF pleocytosis may be absent in
overwhelming meningitis and sepsis.• < 6 months• Focal deficit at presentation• Pnemococcal organism
PREVENTION
• Immuno prophylaxis : - Hib vaccine - routine- Meningococcal vaccine - epidemics
PREVENTION
• Chemo prophylaxis: ( for house hold contacts)1. H influenza : Rifampicin : 20 mg/kg/day, single
dose/day for 4 days 2.Meningococcus : Rifampicin : 20 mg/kg/day, in
2 divided doses for 2 days Or
Ciprofloxacin- single dose 500mg
Thank youDownload more documents and slide shows on The Medical Post
[ www.themedicalpost.net ]