INTERESTING CASE OF ENCEPHALITIS

DR VASIF MAYAN M.C.,M1 UNIT

HISTORY

43 year old previously healthy maleReferred as case of

Fever 6 days(High grade with chills)

Vomiting 4 daysSeizures 4 days (2-3 epsiodes)LOC 2 days

Past historyNo history of hypertensionNo history of DiabetesNo history of Seizure disordersNo history of malaria

examination Stuporous Eye opening to pain PERL 3mm+

No pallor/icterus/cyanosis/clubbing No Bilateral Pitting pedal edema Febrile 39˚C Pulse rate 98/mt BP 130/80mm Hg RR 18/mt SpO2 97% with room air

NEUROLOGICAL EXAMINATION Stuporous, eye opening to pain, PERL 3mm+

moves limbs to painful stimuliBrainstem reflexes preservedTone normal in all 4 limbsDTR preservedPlantars Bilateral FlexorMeningeal signs Positive, Neck stiffness +Fundus examination : No hemorrhage/ No papilledema

OTHER SYSTEMSCVS

S1,S2 +, Normal, No murmurs

RSNVBS, No crackles / No wheeze

P/ASoft, No organomegalyBowel sounds presents

INVESTIGATIONS RBS 116 mg% TC 6800/mm3

DC N59 L47 E1 M3 Hb 12 Gm% PCV 38% PLC 1 lakh/mm3

S.Creatinine 0.8 mg% S.Urea 32 mg% Urine Analysis WNL VCTC Non Reactive

NEUROLOGICAL EVALUATIONCT Brain No focal lesions, Normal

CSF AnalysisProtein 54mg%Glucose 51mg%C&S No growthCytology No cells seen

Provisional DiagnosisACUTE MENINGO-ENCEPHALITIS

Treatment Inj Ceftriaxone 2gm iv BD Inj Metronidazole 500mg iv tds Inj Ampicillin 2gm iv qidTab Chloroquine 150mg 4 stat f/b 2 stat after 8hrs via RT Inj Aciclovir 200mg iv tds Inj Phenytoin 100mg iv tdsFluidsRTF and other supportive measures

Paul bunnel test

SCRUB TYPHUS

Started on Doxycyclin 100mg BDDramatic recoveryDischarged in 7days

“Tsutsugamushi triangle”, one billion people are at risk for scrub typhus (India) one million cases occur annually (India) Mortality rates in untreated patients range from 0-

30% Re-emerging disease

AgentIt is an obligate intracellular gram-ve bacterium that has a large number of serotypes.Does not have a vacuolar membrane; thus, it grows freely in the cytoplasm of infected cells.O. tsutsugamushi has a different cellwall structure and genetic composition than that of the rickettsiae.

Disease transmission

Transmitted to humans and rodents by the bite of infected larvae of the trombiculid mite Leptotrombidium deliense (“chiggers”), which feeds on lymph and tissue fluid rather than blood.

Mode of Transmission

Mite

Rats & Mice

Humans

Mite

No direct person to person transmission

(Accidental host)

CLINICAL FEATURES Illness varies from mild, self-limiting to fatal Incubation period - 6-21 days

fever, headache, myalgia, cough, gastrointestinal symptoms

a primary papular lesion(where the chigger has fed)

enlarges, undergoes central necrosis, and crusts to form a flat black eschar

Associated regional and later generalized lymphadenopathy and a macular rash may appear on the trunk

Neurological - meningoencephalitis Pulmonary - interstitial pneumonia GI - superficial mucosal hemorrhage, multiple erosions,

and ulcers Cardiac - Myocarditis with conduction blocks & CCF Septicemic shock with ARDS, DIC, with renal & hepatic

dysfunctionMortality - 7-30%

complications

Indian studiesAuthor No of Cases Neurological features Outcome

Vivekanandan et.al (2004) 50 Meningitis-14%Altered sensorium- 20%

Mortality-2%

Razak et.al(2004) 29 Meningoencephalitis-20%Cerebellar signs-3%

All improved

Mahajan et.al(2006) 27 Meningoencephalitis-14.8% Mortality-3.7%

Mahajan et.al(2010) 21 Seiures-19%Altered sensorium-23.8%

Mortality-14.2%

Chrispal et.al(2010) 189 Altered sensorium-22.2%Seizures-6.3%

Meningitis-20.6%

Mortality-12.2%

Investigations Hemogram- Leukopenia, thrombocytopenia Coagulopathy Elevation of liver enzymes and bilirubin - indicating hepatocellular damage ↑ Creatinine, Proteinuria Chest X-rays- Reticulonodular infiltrates CSF examinations show a mild mononuclear pleocytosis with normal glucose levels

Diagnostic investigationsTest CommentsWeil Felix Detects cross-reacting antibodies to Proteus mirabilis OX-K

4-fold ↑ in titre to OXK single titre ≥ 1:160 also diagnosticLacks sensitivity & but is specific

ELISA Detects Ab against infectious agents by using pooled human seraHigher sensitivity & specificity

Western Blot Presence of a 41-kD band Higher sensitivity & specificity

Indirect Fluorescent Assay Conclusive diagnosis: 4-fold ↑ in IFAs in paired serum obtained 2 wks apart Currently considered gold standard

PCR amplification most sensitiveLimited availability, expensive

Isolation Can be isolated & cultured by inoculating intraperitoneally into white mice not used routinely

treatment Recommended regimen- Doxycycline (2.2 mg/kg/dose bid PO or IV, maximum 200 mg/day for 7-15 days)

Chloramphenicol (50-100 mg/kg/day divided every 6 h IV) 500 mg qid orally for 7-15 days for adults

Azithromycin (500 mg orally for 3 days)

Rifampicin (600 to 900 mg/day)

Take home messages Scrub typhus is a growing and emerging disease grossly under-diagnosed due to its

non-specific clinical presentation, limited awareness, and low index of suspicion

consider as a differential diagnosis in acute febrile illness with thrombocytopenia, renal impairment, LFT abnormalities, altered sensorium,encephalitis, pneumonitis, or ARDS

WEIL FELIX test very Specific

Early diagnosis and treatment are imperative to reduce the mortality and the complications associated with the disease

Thank you