21
Autoimmune Encephalitides Dr.Roopchand.P.S Senior Resident Academic Department of Neurology

Autoimmune encephalitides

Embed Size (px)

DESCRIPTION

Autoimmune encephalitis

Citation preview

Page 1: Autoimmune encephalitides

Autoimmune Encephalitides

Dr.Roopchand.P.SSenior Resident AcademicDepartment of Neurology

Page 2: Autoimmune encephalitides

Introduction.

• Autoimmune Encephalitis resulting from an attack of the brain by the body's immune system– Acute Disseminated Encephalitis (ADEM)– Hashimoto's Encephalitis– Rasmussen's Encephalitis– NMDA-Receptor Antibody Encephalitis– Limbic Encephalitis

Page 3: Autoimmune encephalitides

ADEM

• occurs in association with an immunization or vaccination (postvaccination encephalomyelitis) or systemic viral infection (parainfectious encephalomyelitis).

• perivascular inflammation, edema, and demyelination within the CNS in characteristic.

Page 4: Autoimmune encephalitides

• Postvaccination Acute Disseminated Encephalomyelitis.– subject of medicolegal controversy.

• Measles-Induced Acute Disseminated Encephalomyelitis.– complicate 1 in 400 to 1 in 1000 cases of measles

infection.• Idiopathic Acute Disseminated

Encephalomyelitis– in the setting of nonspecific viral illness.

Page 5: Autoimmune encephalitides

• bilateral ON• loss of consciousness,• Meningismus• loss of deep tendon reflexes and retained

abdominal reflexes in the presence of Babinski sign

• central body temperature over 100°F• severe shooting limb pains.

Page 6: Autoimmune encephalitides

• development of a focal or multifocal neurological disorder following exposure to virus or receipt of vaccine.

• peak dysfunction within several days.• Recovery can begin within days• Complete resolution day to months.• Measles virus–associated ADEM may carry a

worse prognosis.

Page 7: Autoimmune encephalitides

Investigations

• MRI: multifocal CNS lesions.– majority of the T2 lesions enhance, suggesting

they were of recent onset.– after several weeks, lesions show at least partial

resolution.• CSF:– Normal pressure, cells <100/mm3, moderate

increase in protein.– OCB not usually seen.

Page 8: Autoimmune encephalitides

• The current favored therapy for ADEM is high-dose corticosteroids.

• Acute Hemorrhagic Leukoencephalitis.• Isolated ON• Cerebellitis• ATM.• c/c recurrent.

Page 9: Autoimmune encephalitides

Hashimoto encephalopathy

• acute to subacute• evidence of cognitive impairment• variable psychiatric symptoms, alteration in

consciousness, hallucinations• Involuntary movements, seizures, myoclonus,

opsoclonus, chorea, ataxia, stroke like episodes, and myelopathy.

• Adolescent females are mostly affected.

Page 10: Autoimmune encephalitides

• Diagnosis:– Clinical triad of neuropsychiatric symptoms,

detection of antimicrosomal or antithyroglobulin antibodies, and exclusion of other causes.

– antithyroid– peroxidase, antithyroglobulin, – lesser extent thyroid-stimulating hormone

receptor–blocking antibodies.– α-enolase

• autoimmune cerebral vasculitis perhaps related to immune complex deposition.

Page 11: Autoimmune encephalitides

• CSF show moderately elevated protein, may be positive for anti thyroid Ab, OCB seen

• EEG: slowing, triphasic waves, epileptiform discharges.

• MRI usually normal, occasionally non-specific sub cortical white matter T2 signal changes.

• Thyroid status may be normal.• Treatment: short course high dose steroids

(55% full recovery)• Recurrence – continued steroids, IVIG, other

immunomodulatory drugs.

Page 12: Autoimmune encephalitides

Rasmussen's encephalitis

• chronic focal encephalitis (CFE)• rare inflammatory neurological disease• frequent and severe seizures, loss of motor

skills and speech, hemiparesis encephalitis and dementia.

• Usually <15 yrs• Affects one cerebral hemisphere.

Page 13: Autoimmune encephalitides

• auto-antibodies against the glutamate receptor GluR3.

• T lymphocyte mediated destruction of neurons.

• C/F:– mostly affects children(avg 6yrs)– prodromal stage ,Acute stage and residual stage.

Page 14: Autoimmune encephalitides

• Diagnosis is usually clinical.• EEG shows slowing in affected hemisphere.• MRI : gradual shrinkage of the affected

hemisphere with signs of inflammation or scarring.

• Treatment:– Control of seizures– Steroids, IVIG– Severe cases Hemispherectomy.

Page 15: Autoimmune encephalitides

Anti-NMDA receptor encephalitis:

• acute form of encephalitis.• Potentially Lethal.• caused by autoimmune reaction against NR1- and

NR2-subunits of the glutamate NMDA receptor.• Associated with ovarian teratomas.• Previously thought entirely as a paraneoplastic

manifestation.• psychiatric symptoms or memory problems,

seizures, unresponsiveness , dyskinesias, autonomic instability, hypoventilation.

Page 16: Autoimmune encephalitides

• MC in young women and children.• Treatment with Steroids, IVIG.– PLEX– Cyclophosphamide and /or rituximab.

Page 17: Autoimmune encephalitides

Limbic and Brainstem Encephalitis:

• Limbic encephalitis: Confusion,depression, agitation, anxiety, memory deficits, dementia, and partial complex seizures.

• Brainstem encephalitis: oscillopsia, diplopia, dysarthria, dysphagia, gaze abnormalities, and subacute hearing loss.

• Symptoms can overlap.

Page 18: Autoimmune encephalitides

• MRI:– unilateral or bilateral mesial temporal lobe

abnormalities on T2-weighted and FLAIR images’– The temporal-limbic regions may be hypointense on

T1-weighted sequences and may enhance with contrast.

• Associated with testicular germ cell tumors, Hodgkin lymphoma, thymoma.

• Antigens:– Intra cellular: Hu, Ma2, CV2/CRMP5– Cell surface antigens: AMPA receptors, leucine-rich

glioma inactivated 1 (LGI1) and γ-aminobutyric acid type B [GABA-B] receptors.

Page 19: Autoimmune encephalitides

Graus and Saiz criteria(2005)

All four of• Subacute onset (<12 weeks) of seizures, short-term

memory loss, confusion, and psychiatric symptoms• Neuropathologic or radiologic evidence (MRI, SPECT, PET)

of involvement of the limbic system• Exclusion of other possible aetiologies of limbic dysfunction• Demonstration of a cancer within 5 years of the diagnosis

of neurologic symptoms, or the development of classic symptoms of limbic dysfunction in association with a well-characterized paraneoplastic antibody (Hu, Ma2, CV2, amphiphysin, Ri)

Page 20: Autoimmune encephalitides

Treatment:

• immunomodulation with steroids and IVIg.– The likelihood of improvement is higher if the

disorder is associated with antibodies to cell-surface receptors or ion channels.

• removal of the antigenic source (tumor) and antibodies with antibody depleting treatments are often successful.

• Treatment is disappointing when antigens are intracellular.

Page 21: Autoimmune encephalitides

THANK YOU