Diagnostic Criteria for Possible AIE
Diagnostic Criteria for Possible AIE
Diagnosis requires fulfillment of the 3 following criteria
.
Subacute onset (rapid progression of less than 3 months) of working memory deficits (short term memory loss), altered mental status*, or psychiatric symptoms
*Altered mental status:
- Decreased or altered level of consciousness, lethargy or personality change.
.
At least one of the following
a. New focal CNS findings
b. Seizures not explained by a previously known seizure disorder
c. CSF pleocytosis (white blood cell count of more than five cells per mm³)
d. MRI suggestive of encephalitis.
.
Reasonable exclusion of alternative causes.
Reference: Graus F, Titulaer MJ, Balu R, et al. A clinical approach to diagnosis of autoimmune encephalitis. Lancet Neurol. 2016;15(4):391-404. doi:10.1016/S1474-4422(15)00401-9
Diagnostic Progression in AIE (excluding ADEM, Bickerstaff’s)
Progression from a possible diagnosis to a probable or definite diagnosis requires antibody positivity or other positive paraclinical findings (imaging/CSF) in the case of antibody negative cases. See the chart below for further details
Reference: Hahn C, Budhram A, Alikhani K, et al. Canadian Consensus Guidelines for the Diagnosis and Treatment of Autoimmune Encephalitis in Adults. Can J Neurol Sci. Published online February 5, 2024. doi:10.1017/cjn.2024.16
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