EncephalitiEncephalitiss

Dr.Ibrahim Khasraw Jaf

Department of Pediatrics

School of Medicine

Sulaymani University

Definition-:

It is inflammatory process of the brain parenchyma , mainly caused by special types of viruses , leading to mortality and morbidity among

children due to cerebral dysfunction.

Classification-:

According to the onset;

Acute: abrupt onset with rapidly developing clinical features , e.g.: enteroviruse , herpes

simplex virus encephalitis.

Subacute: slower developing symptoms within days to few weeks , e.g.: measles ,

HIV.

Chronic: develop over long period(months),

e.g.: S.S.P.E. , T.B . .

Classification (continue..)-:

According to anatomical site of involvement;

Focal: when one or more points of the brain lobes involved like , temporal , parietal

lobes of the brain , limbic system.

Diffuse: (generalized) when whole brain tissues involved .

Classification (continue..)-:

According to pathological process;

Direct: when the infective agent itself invade the brain and induce inflammation.

Indirect (post infectious) : when the infectious agent , after cure induce immune mediated inflammatory reaction in the brain due to antibody-antigen reaction , e.g.: post ,

chickenpox crebellitis .

Etiology-:

Viral : includes these viruses according to the incidence.

Enteroviruses : about 50% of cases due to these groups of viruses , e.g.: coxachi &

echo viruses (non polio viruses).

Herpes virus group : about 10-20% of cases (herpes simplex virus , Epstein-Barr virus , cytomegalovirus , varicella zoster virus ,

human herpes viruse 6,7 ).

Etiology (continue..)-:

Other viruses : may be caused by viruses which cause systemic diseases rarely as a part of complication they cause encephalitis like influenza virus , measles , mumps ,

rubella (german measles) , rabies , HIV.

Nonviral causes : (mainly bacteria) : like mycoplasma , rickettsia , fungi , parasites , mychobacterium(T.B.) , collagen tissue ,

e.g.: S.L.E. .

1/3rd of cases still no cause could be found.

Clinical features-:

-The onset is sudden or insidious (gradual). -Prodromal phase usually starts with flue-like

illness with cough , sore throat , fever. -Headache , nausea , vomiting , blurring of

vision , papillodema (due to increase intra cranial pressure) .

-Disturbance of consciousness , from lethargy to deep coma ,covulsion.

-Focal neurological signs : according to area involved.

-Skin rash & conjunctivitis in special types.

Diagnosis-:

- -C.S.F. : show lymphocytic pleocytosis , slight increase in protein with normal sugar (only decreased in mumps encephalitis) occasionally may be normal . Very high protein with very low sugar suggestive of tuberculus

infection (e.g.: tuberculoma ).

-E.E.G. : show diffuse slow wave , focal changes e.g.: temporal lobe abnormal finding

highly suggestive of herpes simplex virus.

Diagnosis (continue..)-:

-Neuro imaging : C.T. scan , M.R.I. may be normal but may show focal lesion according

to the site involved or may show diffuse brain swelling . Temporal lobe lesion suggestive of

herpes simplex virus(H.S.V.).

-Serology : antibody-antigen reaction test rising of titer against special virus like H.S.V.

4 fold or Igm type significant .

Diagnosis (continue..)-:

-Viral culture of C.S.F. , urine , stool , nasopharyngeal swab commonly reveal the

virus.

-P.C.R. : it is identify the virus through its DNA , it is highly specific and sensitive for C.S.F. ,

nowadays replaced the brain biopsy.

-Brain biopsy : the last and invasive procedure rarely done for special types like T.B. & non infectious causes

Differential diagnosis-:

-Reye syndrome(aform of hepatic encephalopathy).

-Hypoglycemia.

-Collagen vascular disease (C.V.A.).

-Drugs & toxins.

-Hypertensive encephalopathy.

Treatment-:

Non specific : measures to be taken like admission to I.C.U. then A,B,C,D.

Control convulsions by phenobarbiton.

Decrease intra cranial pressure by dexametasone

and or mannitol.

Pay attention to fluid & electrolytes.

Treatment (continue..)-:

Specific : intra venous acyclovir for H.S.V , V.Z.V. they are only viruses susceptible to drug therapy , otherwise there is no specific

treatment for other viral encephalitis.

Antibiotics for bacterial causes , e.g.: mycoplasma (erythromycin) , T.B. (anti T.B.).

Others according to the cause , e.g. steroid for S.L.E. .

Complication -:

Happen when there was no recovery within 2-3 weeks and they are common in spite of

proper treatment like;

-Death : generally occur in about 5% of cases.

-Paresis , spasticity , ataxia.

-Cognitive impairment.

-Epilepsy due to recurrent seizures.

Prevention-:

Only two viral forms of encephalitis could be prevented by vaccination against them , they are influenza virus and rabies virus vaccines done for

whom they are liable to get them.

Figure:   EBV encephalitis. a Axial FLAIR image demonstrates abnormal T2-W signal in the bilateral frontal cortex and subcortical white matter. This is a typical pattern for viral encephalitis. The multiple vascular territories involved make ischemia unlikely. Additionally, a child presenting with multifocal strokes of this magnitude would have a profound clinical presentation with fixed neurologic deficits. b, c Axial (b) and coronal (c) FLAIR images demonstrate increased signal in the bilateral basal ganglia reflecting the unique tropism of EBV for this area

Meningitis :Definition:

It’s inflammation of leptomeninges caused by pathogenic microorganisms:

Bacteria:-strept.pneumoniae ,H.infleunzae ,meningococus

Viruses:- H.S.V,H.I.V,C.M.V,Mumps,enterovirus, HLCM.

Fungi:-coccidiomycosis,Histoplasmosis,

Uncommon:-Lyme disease ,catscratch dis. ,T.B. ,Toxoplasmosis,

Entameba: Acanthomeba

:Acute bacterial(septic)meningitis-:Bacteriology:

-Strept.pn.,nowadays commonest one -H.infleunzae,about 5% of cases(b.of vaccination.)

-Meningococcus (Niserea meningitidis) .rare but most serious and Weakest bacterium.

-Staph.aureas, common in post-surgical cases&penetrated wounds.

-Pneunococcus:in fracture base of skull &C.S.F leak

Clinical features:

*It’s variable according to the age of the patient:

-Neonates and infants:

*Fever or hypothermia, drowsiness' or irritability

*Tense anterior fontanel, convulsion, unexplained

*Repeated vomitting,lethargy, relactant to feed.

-Older aged children:

, meningisim *headache ,repeated vomiting ,toxicity (neck stiffness ,kerning&brudzinesky signs.)

C.F.continue:Skin rash in form of purpura ,called purpura

Fulminance(in meningococcemia)

Adrenal hemorrhag:shock state called (water -house fridrichsen syndrom)

-Signs of increase intracranial pressure (hypertention,bradycardia ,irregular respiration).

-Focal nearological signs: ptosis , 6th N.pulsy, anisocoria

Usually there's no papilodema.

Diagnosis:

-C.B.P. :Shows neutrophil leukocytosis,with picture ofacute bacterial inf.

-Positive acute phase reactants: high E.S.R.,+Ve C.R.P

-Blood culture &sensitivity may be +ve in about 90%

of cases.

-L.P for C.S.F. examination: us .show increase preasure, cell count,(majority are neutrophils),protein ,

&decrease sugar,coloure may be turbid.

-Signs of consumptive coageolopathy.or D.I.C.in

meningococcemia .

Contraindications of L.P:.

*Cardiopulmonary instability

*Infection in the site of L.P.

*Bleeding tendency.

*Papillodema.( absolute C.I.)

Normal C.S.F. parameter:

*Colure : clear

*pressure: <160mmH2O

*Cell count: 0-5Lymphocytes, No Neutrophils

*Protein: 15-35mg/dl

*Sugar: 50-80mg/dl(or 2/3rd of blood sugar)

*Culture: -ve .

But normal C.S.F. doesn't exclude meningitis.

D.Dx-:

*Encephalitis

*Intracranial hemorrhage.

*Encephalopathy.

*Posterior fossa tumore.

Treatment:

-Its one of ped. Top medical emergensy.

-Admission to hospital &in special isolated word.

-Control convulsion.

-Give I.V. fluid 2/3red of the daily requirement(to pre

-vent S.I.A.D.H.(

-Anti-biotics :Empirical choice is combination of vancomycine +one of third genration cephalosporins

-)cefotaxime or ceftriaxon (double of the simple dose.

-Steroid:Dexamethasone twice daily for two days.

Comlications:

*Early :Sub-dural effusion, Hydrocephalus,c.v.a .

Cerebral herniaition ,D.I.C, Adrenl hemorrhage

)water-house fridrichsen syndrome(

*Late :cerebral abscess ,cerebral pulsy,mental retardation, epilepsy, deafness,blindness .

Prevention: *Meningococcal vaccine for overcrowded areas

* Pneumococal vaccine: for Immune compromised children .

* Chemoprophylaxis.:Rifampicin10mg/kg/dos

12hourly for 2 days for contacts with meningoco- Ccemia .

& 10mg/kg/day single dose for 4days in H.infl.

- single inj. Of ceftriaxon ,oral ciprofloxacine are

Ulternatives.

THE END THANKS