Table 1.

Diagnostic findings.

Serum basic diagnostics and blood count	Normal renal, liver, and thyroid values; Slightly increased C3d concentration (11.1 mg/l; reference value <9 mg/l); Normal blood count.
Serum autoantibody analyses	Normal thyroid autoantibodies (against thyroglobulin, thyroid peroxidase, and thyroid-stimulating hormone); Rheumatological screening: increased antinuclear antibodies (titer: 1:400; reference value <1:50) without clear extractable nuclear antigens; the anti-nucleosome antibodies were weakly positive; No antibodies against intracellular onconeural antigens (Yo, Hu, CV2/CRMP5, Ri, Ma1/2, SOX1), or the intracellular synaptic antigens (GAD, amphiphysin).
Cerebrospinal fluid (CSF) analyses	Normal white cell count, no blood–brain barrier dysfunction (normal protein concentration and albumin quotient); No CSF-specific oligoclonal bands, but a weak identical band in the CSF and serum; Antibodies against neuronal cell surface antigens [NMDAR, AMPA-R, GABA-B-R, VGKC complex (LGI1, Caspr2)] were negative.
Cerebral magnetic resonance imaging (1.5 T)	Normal brain findings; Additional examination findings included a benign lesion of the right frontoparietal skull without contrast enhancement (most likely equivalent with dermoid cysts; the criteria for monoclonal gammopathy of undetermined significance or multiple myeloma were not fulfilled).
Electroencephalography (during the first admission to our clinic in 2013, under the treatment with clozapine, aripiprazole, and citalopram)	Frontal accentuated intermittent rhythmic delta activity (FIRDA) and generalized 3 Hz polyspike wave complexes.