The psychiatric profiles of patients with temporal lobe epilepsy associated with neuronal auto-antibodies

Abstract

Objective: Neuronal auto-antibodies (NAA) have recently been shown in some patients with chronic temporal lobe epilepsy (TLE). Psychiatric comorbidity is a significant part of the TLE course and a different profile can be a marker for "autoimmune" epilepsy. For this reason, we aimed to determine the psychiatric profiles of TLE patients associated with NAA and their differentiating features. Methods: The sera of the included TLE patients have been tested for 8 neuronal auto-antibodies. The standardized, detailed psychiatric interviews and questionnaires (International Neuropsychiatric Interview; M.I.N.I. Turkish edition, Yale - Brown Obsessive Compulsive scale (YBOCS), The Scale for the Assessment of Positive Symptoms (SAPS)) were performed by the same researcher blindfolded to the NAA status of the patients. Results: We evaluated 37 consecutive patients (12 male, 25 female) with TLE. NAAs had already been detected for research purposes in the sera of 20 included patients; the antibodies were found against contactin associated protein-2 (CASPR2) in 7, N-methyl-D-aspartate receptor (NMDAR) in 6, voltage-gated potassium channel complex (VGKC-complex) in 3, glycine receptor in 3 and glutamic acid decarboxylase in one patient. Social phobia was found remarkably common in the seronegative group (p:0.015). Other psychiatric symptoms did not show any difference between the seropositive and seronegative groups. Conclusion: We could not demonstrate an alarming psychiatric profile related to NAAs in chronic TLE patients, in our small sized study. It was important to note that depression and psychosis are more frequent in patients with NAA, whereas seronegative patients displayed social phobia more frequently.