There has been long discussion about the increased prevalence of electroencephalogram (EEG) abnormalities and their significance in patients with schizophrenia. ^{Reference Huber and Penin1-Reference Tucker, D'Etre, Harrow and Galser4} Although interictal epileptiform discharges presumably indicate a higher risk for seizures, ^{Reference Walczak, Jayakar, Engel and Pedley5} such abnormalities alone in a clinical case of schizophrenia are generally not regarded as having strong implications for antipsychotic therapy.

Here, we report the case of a 17-year-old student who over a period of several months developed a paranoid-hallucinatory syndrome, feeling persecuted, sidelined and out-casted by his peers. He also experienced changes in auditory perception, reported supersensitive hearing and auditory hallucinations of backbiting whispering voices of his peers. There was a prodromal phase with increasing social withdrawal, affective flattening and a drop in school grades over a period of 2 years prior to the diagnosis of schizophrenia by an out-patient psychiatrist. Treatment with 250 mg quetiapine led to some improvement but not remission. Aged 13 he had been in a road traffic accident, with subtle contusions and subarachnoid bleeding which fully recovered without any other neurological, psychiatric, cognitive or magnetic resonance imaging symptoms or signs. A routine clinical EEG showed infrequent 3 Hz spike-and-slow-wave complexes (SWCs). Video telemetry for 3 days clearly showed 3 Hz SWCs with a duration of between 200 and 3500 msec and an average frequency of about 8 per hour and a peak frequency of 18 per hour without clinical seizure correlates. Assuming that the EEG findings might play a role in the genesis of schizophreniform syndrome, medication was changed to valproate monotherapy. This resulted in full clinical and cognitive remission and considerable improvement of the EEG within a few weeks. Subsequently, the patient’s school grades returned to top levels.

The clinical relevance of such an EEG finding in a patient with schizophrenia is still an unresolved question. ^{Reference Galderisi, Mucci, Volpe and Boutros6} In spite of an intensive historical discussion of this issue, to our knowledge this is the first description of a clinical case of schizophrenia with generalized 3 Hz SWCs and excellent clinical response to valproate monotherapy. In our view, this case illustrates three clinically important points: (1) it is worthwhile doing EEG studies in patients with schizophrenia; (2) non-ictal SWCs might play a pathogenetic role in a small subgroup of patients with schizophrenia; and (3) in clear-cut cases of SWCs in patients with schizophrenia but without clinical seizures, a therapeutic trial with anticonvulsant medication might be warranted.