Question?Question?

• Differentials Diagnosis : Differentials Diagnosis : Epidemic encephalitis BEpidemic encephalitis B and and Epidemic cerebrospinal meningitisEpidemic cerebrospinal meningitis

Differentials

EtiologyEpidem-iology

Lab PreventionClinical

manifestationTreatment

Dr.Huijuan ZhouDr.Huijuan ZhouDept. of Infectionous Diseases,RDept. of Infectionous Diseases,R

uijin Hosp.uijin Hosp.

Epidemic encephalitis BEpidemic encephalitis Bor Japanese encephalitisor Japanese encephalitis

General descriptionGeneral description• Epidemic encephalitis B is Epidemic encephalitis B is acute infectious diseaseacute infectious disease

caused by encephalitis B viruscaused by encephalitis B virus 急性传染病，乙脑病毒急性传染病，乙脑病毒引起引起

• Usually occurs in summer &fall , from July to SepteUsually occurs in summer &fall , from July to Septembermber 秋夏多发秋夏多发

• Pathologic lesions: cerebral parenchymaPathologic lesions: cerebral parenchyma 脑实质炎症脑实质炎症为主为主

• virus is transmitted by Culex mosquitovirus is transmitted by Culex mosquito 库蚊库蚊• AreaArea ：： distribution of J.E in Asiadistribution of J.E in Asia• Clinical feature: high feverClinical feature: high fever 高热高热 altered consciousnessaltered consciousness 意识障碍意识障碍 convulsionconvulsion 抽搐抽搐 meningeal irritationmeningeal irritation 脑膜刺激症脑膜刺激症 respiratory failurerespiratory failure 呼吸衰竭呼吸衰竭

EtiologyEtiology

• Causative agent:Causative agent:Encephalitis B VirusEncephalitis B Virus,, Japanese encephalitis virusJapanese encephalitis virus• genus flavivirus of flaviviridae genus flavivirus of flaviviridae 虫媒病毒虫媒病毒 BB 组组 – 黄病毒科– 黄病毒科• virion is spheric, diameter: 15 - 22nmvirion is spheric, diameter: 15 - 22nm 球形球形• single strain of positive-sense RNA,single strain of positive-sense RNA, 单股正链单股正链 RNARNA• Resistance: unstable in environment, sensitive to heat, disinfResistance: unstable in environment, sensitive to heat, disinf

ectants, ultraviolet raysectants, ultraviolet rays• antigenicity: stableantigenicity: stable

• hemagglutination inhibiting Abhemagglutination inhibiting Ab• complement fixing Abcomplement fixing Ab• neutralizing Abneutralizing Ab

EpidemiologyEpidemiologySource of infectionSource of infection domestic animals: pig, horse, dog domestic animals: pig, horse, dog poultry: chicken, duck, goosepoultry: chicken, duck, goose patients: patients: Others: batOthers: bat

EpidemiologyEpidemiology

Route of transmissionRoute of transmission insect borne: mosquito biting , insect borne: mosquito biting , vector: mosquito, culex tritaeniorhynchus.vector: mosquito, culex tritaeniorhynchus.

vector 传媒

reservior host

Survived winter mosquitoes

EpidemiologyEpidemiology

• vectorvector 传媒传媒

Culex mosquito

Image: Image: CulexCulex mosquito laying eg mosquito laying eggs.gs.

http://www.cdc.gov/ncidod/dvbid/westnile/culex-image.htmhttp://www.cdc.gov/ncidod/dvbid/westnile/culex-image.htm

EpidemiologyEpidemiology

The distribution of J.E in The distribution of J.E in AsiaAsia

PathogenesisPathogenesis

virus vector replication in mononuclear-phagocyte

system (MPS)

cellular immunity↓No. of virus of invasion

blood-brain barrier

blood stream brief viremia

onset of illness 脑 炎 subclinical inf.

mosquito biting

PathologyPathology Place of lesion: Place of lesion:

– all of CNSall of CNS– cerebral cortex, midbracerebral cortex, midbra

in and thalamus in and thalamus 丘脑丘脑 ..

microscopic examination:•vascular lesion: endothelial cells swelling, necrosis•neuron degeneration & necrosis•neurogliocyte hyperplasia & inflammatory cells infiltration,•perivascular cuffing , neuronophagia.

The pathology consist of perivaThe pathology consist of perivascular congestion and hemorrhscular congestion and hemorrhageage

Clinical manifestationClinical manifestation

• Incubation period:10~14 days (4~21days )Incubation period:10~14 days (4~21days )• Typical encephalitis BTypical encephalitis B -Initial period-Initial period -Crisis period-Crisis period -Convalescent period-Convalescent period -Sequela period-Sequela period

• Initial period : on the 1st to 3rd Initial period : on the 1st to 3rd daysdays– abrupt onsetabrupt onset– fever with headache , nausea, fever with headache , nausea,

vomiting lethargy,vomiting lethargy,

– abdominal pain , diarrhea,abdominal pain , diarrhea,

Clinical manifestationClinical manifestation

Clinical manifestationClinical manifestationCrisis periodCrisis period ：： on the 4th ~10th dayson the 4th ~10th days

– high fever: >40 , sustained for 7~10 days .℃high fever: >40 , sustained for 7~10 days .℃ 持持续稽留高热：热度高、热程长→病情重续稽留高热：热度高、热程长→病情重

– altered consciousness:altered consciousness: 意识障碍：意识障碍： lethargy, stupor, semicoma, coma.lethargy, stupor, semicoma, coma. 嗜睡、昏嗜睡、昏

睡、昏迷睡、昏迷– convulsion or twitch:(40~60%) convulsion or twitch:(40~60%) 惊厥，抽搐惊厥，抽搐– respiratory failure: 15~40%respiratory failure: 15~40%

Clinical manifestationClinical manifestation• Convalescent periodConvalescent period 恢复期：恢复期： after the course :dafter the course :d

ay 8~10ay 8~10– T drop to normal in 2~5 daysT drop to normal in 2~5 days– neurologic function regain gradually(2W)neurologic function regain gradually(2W)– remain some behavioral & psychologic abnormaremain some behavioral & psychologic abnorma

lities, aphasialities, aphasia 失语失语 , dementia, dementia 痴呆痴呆 , rigidity para, rigidity paralysislysis

• Sequela periodSequela period 后遗症期后遗症期– 5~20% patients5~20% patients– >6month >6month – behavioral & psychologic abnormalitiesbehavioral & psychologic abnormalities

.

ComplicationsComplications

• 10%10%• bronchopneumoniabronchopneumonia ： ： occurs mostoccurs most• incomplete expansion of the lungincomplete expansion of the lung•Septicemia• Urine infectionUrine infection• bedsorebedsore 褥疮褥疮

Laboratory FindingsLaboratory Findings

-Blood picture: WBC 10~20×109 /L

neutrophil >80%

-Cerebrospinal fluid aseptic meningitis 无菌脑膜炎 ： transparent or slightly cloudy, pressure may be elevatedpleocytosis: 50~500×106/Lprotein may be elevated mildlyglucose and chloride are normal

lumbar plumbar punctureuncture腰穿腰穿

Laboratory FindingsLaboratory FindingsCerebrospinal fluidCerebrospinal fluid CSF: CSF: aseptic meningitisaseptic meningitis

normalnormal Viral Viral meningitismeningitis

purulent purulent

meningitismeningitis

tuberculous menituberculous meningitisngitis

appearanceappearance transparentransparentt

transparent transparent or slightly or slightly

cloudycloudy

cloudycloudy Ground glass Ground glass alikealike

pressure(pressure(cm cm HH22O)O)

5-125-12 may be may be elevatedelevated

>20>20 may be may be elevatedelevated

pleocytosispleocytosis /L/L 0~8 x 0~8 x 101066

50~550~500×100×106/L06/L

>1000 x >1000 x 101066

100-500 x 10100-500 x 1066

proteinprotein(g/L)(g/L) 0.15~0.40.15~0.455

may be may be elevated elevated

mildlymildly

~1~1 1~2 ou >21~2 ou >2

glucoseglucose((mmol/mmol/L)L) 2.8~4.2.8~4.

22

normalnormal ↓↓ ↓↓

((mmol/Lmmol/L)) 120~130120~130 normalnormal ↓↓ ↓↓

smearsmear -- -- ++ ++

实验室检查实验室检查Serological test:Serological test:

– specific IgM Ab: specific IgM Ab: blood or CSF,blood or CSF,

3~4d after onset, peak on 2 week3~4d after onset, peak on 2 week– complement fixing Abcomplement fixing Ab– hemagglutination inhibition Abhemagglutination inhibition Ab– neutralized Abneutralized Ab

pathogenic test pathogenic test -virus isolation: -virus isolation: blood, CSF, brblood, CSF, br

ain tissueain tissue -RT-PCR :-RT-PCR : RNA RNA

Image testImage test

DiagnosisDiagnosis• 流行病学资料流行病学资料 Epidemiological dEpidemiological d

ata:ata:– 7~9 month7~9 month– <10yrs<10yrs

• 临床表现临床表现 Clinical manifestation:Clinical manifestation: -fever, headache, vomiting, alter-fever, headache, vomiting, alter

ed consciousness, ed consciousness, -convulsion, meningeal irritation, -convulsion, meningeal irritation,

pathologic reflexes positive.pathologic reflexes positive.• 实验室检查实验室检查 Laboratory findings:Laboratory findings:• WBC, CSF, IgMWBC, CSF, IgM

Differential DiagnosisDifferential Diagnosis• 化脓性脑膜炎化脓性脑膜炎 purulent meningitispurulent meningitis• 结核性脑膜炎结核性脑膜炎 tuberculous meningitistuberculous meningitis• 霉菌性脑膜炎霉菌性脑膜炎 fungicidal meningitisfungicidal meningitis• 中毒性菌痢中毒性菌痢 toxic bacillary dysenterytoxic bacillary dysentery

– high fever,convulsion,coma.high fever,convulsion,coma.

– <24h <24h

– circulatory failure: earlycirculatory failure: early

– stool examination: WBC, RBCstool examination: WBC, RBC

– CSF: normalCSF: normal

– meningeal irritation: negativemeningeal irritation: negative• 其它病毒其它病毒 other viral encephalitisother viral encephalitis : CMV, HSV,EBV,HIV: CMV, HSV,EBV,HIV

TreatmentTreatmentGeneral therapy:General therapy:

– Isolation:Isolation:

preventing mosquito bitipreventing mosquito biti

ng, T<30℃ng, T<30℃– nursing: nursing:

mouth, skin, eye,mouth, skin, eye,

turn overturn over

clapping back clapping back

sputum aspirationsputum aspiration

– fluid & electrolyte supplfluid & electrolyte suppl

ementationementation

TreatmentTreatment

Symptomatic therapySymptomatic therapyhigh fever:high fever:– physical cooling physical cooling

(ice bag, alcohol bathing, cold saline enema(ice bag, alcohol bathing, cold saline enema 低温灌肠低温灌肠 ))

– drug cooling drug cooling

antipyreticantipyretic 退热剂退热剂 subhibernationsubhibernation 冬眠治疗冬眠治疗 ::

chlorpromazine 0.5~1mg/kg/timechlorpromazine 0.5~1mg/kg/time 氯丙嗪氯丙嗪 phenergan 0.5~1mg/kg/time phenergan 0.5~1mg/kg/time 异丙嗪异丙嗪 4~6h, 3~5day4~6h, 3~5day

TreatmentTreatment

convulsion: convulsion:

fever: fever: coolingcooling

brain edema: brain edema: 20% mannitol 1~2g/kg/time20% mannitol 1~2g/kg/time

50% glucose50% glucose

dexamethasondexamethason

TreatmentTreatmentrespiratory failure:respiratory failure:

keep airway clearkeep airway clear• sputum aspirationsputum aspiration• turn over , clapping back, postural drainageturn over , clapping back, postural drainage 体位排出体位排出• AerosolizationAerosolization 雾化雾化• inhalation of oxygeninhalation of oxygen

respiratory stimulantrespiratory stimulant 呼吸兴奋剂呼吸兴奋剂 lobeline: adult: 3~9mg/timelobeline: adult: 3~9mg/time

children: 0.15~0.2mg/kg/timechildren: 0.15~0.2mg/kg/time coramine: adult: 0.375~0.75g/timecoramine: adult: 0.375~0.75g/time

children: 5~10mg/kg/timechildren: 5~10mg/kg/time tracheal intubation or tracheotomy, biomotortracheal intubation or tracheotomy, biomotor 呼吸机呼吸机

Anti-virus:Anti-virus:Acyclovir & Gancyclovir, ribavirinAcyclovir & Gancyclovir, ribavirin

New drugNew drug ：：纳洛酮纳洛酮 0.8mg v q2h0.8mg v q2h

Convalescent & sequela periodConvalescent & sequela period– AcupunctureAcupuncture 针灸针灸– massage massage 按摩按摩– exercise etc.exercise etc.

PreventionPrevention• Isolation source of infectiIsolation source of infecti

onon -isolating patients -isolating patients -pig immunization,-pig immunization, killed virus vaccikilled virus vacci

ne: 60~90%ne: 60~90% preventing mosquito ,preventing mosquito , • Protect susceptible popuProtect susceptible popu

lationlation : :vaccinationvaccination

• Cut the route of transmissCut the route of transmissionion （（ importantimportant ））– Kill mosquitoKill mosquito

PreventionPrevention

• vaccination vaccination – Immunity in Immunity in

plan plan