[Sub-acute encephalopathy that responds to steroids without any evidence of autoimmune thyroid disease: a case of non-vasculitic autoimmune meningoencephalitis].

AIM: To report a case of sub-acute encephalopathy with all the extension study negative and with response to steroid therapy.

CASE REPORT: The study involves a 22-year-old female with no relevant past history who presented symptoms of sub-acute encephalopathy consisting in behavioural disorders, generalised seizures and bradypsychia, which gradually progressed to a state of low-level consciousness. While she was in hospital all kinds of diagnostic tests were conducted, the results of which were either normal or negative; the electroencephalogram was repeatedly abnormal and detection of protein 14-3-3 in cerebrospinal fluid was positive. Empirical corticoid therapy was begun with clinical and electrophysiological improvements and the patient recovered completely without any sequelae.

CONCLUSIONS

With no evidence of autoimmune thyroid disease, although non-specific autoimmunity was present, the patient was diagnosed as having non-vasculitic autoimmune meningoencephalitis.