Monitoring the effect of immunotherapy in autoimmune limbic encephalitis using 18F-FDG PET.

Resumen:
A 70-year-old woman with a history of autoimmune hepatitis and renal cell carcinoma presented with subacute cognitive impairment. A brain MRI revealed mild leukoaraiosis, whereas brain F-FDG PET/CT showed diffuse cerebral hypometabolism that resembled some of the patterns described in limbic encephalitis and neurodegenerative diseases. With the suspicion of autoimmune encephalitis, the patient received immunotherapy with dramatic improvement of cognitive function and metabolic normalization at the 2-month follow-up on brain F-FDG PET/CT. Our results demonstrate that brain F-FDG PET/CT might be a useful tool in the assessment of patients with autoimmune encephalitis.