Diagnostic value of single photon emission computed tomography (SPECT) for patients with non-herpetic acute limbic encephalitis.

To evaluate the diagnostic value of SPECT (single photon emission computed tomography) brain blood flow imaging for patients with non-herpetic acute limbic encephalitis (NHALE). A retrospective review of three patients who had clinical symptoms compatible to NHALE and were positive for anti-N-methyl-d-aspartate-type glutamate receptor (GluRε2) antibody. The patients consisted of a 6-year-old female, a 10-year-old female and a 13-year-old male, all of whom had limbic symptoms and were anti-GluRε2 antibody-positive. In all cases, brain MRI failed to detect any abnormality, but SPECT brain blood flow imaging was able to detect blood flow changes. All three cases showed some abnormality in their brain waves, and one of them also developed epilepsy. SPECT brain blood flow imaging may therefore be helpful for diagnosing NHALE which can lead to the development of either epilepsy or cognitive impairment.