How do you approach a mildly positive finding on an autoimmune encephalitis panel when there is no other evidence of encephalitis (such as elevated CSF protein, abnormal imaging, or EEG findings)?

In general, low positive Abs by ELISA or radioimmunoprecipitation assays have low predictive value for neurological disease and cancer outside of specific clinical contexts (e.g. a PQ of 0.03 nmol/L in a patient with myasthenic syndrome).

For encephalitis, GAD65 < 20 nmol/L, and PQ type calcium chann...

Antibody levels can fluctuate; therefore, I don’t think there’s one good answer. If one goes with clinical symptomatology and follows the patient clinically, it might be too late because the fundamental premise is to get treatment initiated early. So I tend to RX antibody negative cases because the ...