[Epileptiform activity in psychiatric disorders in children].
BACKGROUND
Abnormalities are often observed in the electrical activity of the brain in patients with brain dysfunction.


METHODS
We conducted a retrospective analysis of the results of electroencephalogram studies carried out between August and December 2006 on children who had been clinically diagnosed with a psychiatric disorder, without taking into account those with epilepsy.


RESULTS
A total of 1000 electroencephalogram (EEG) studies were reviewed; the age of the patients ranged from 0 to 18 years, with an average of 9.7 years, and the ratio between sexes was 67.9% males and 32.1% females. The four most frequently observed psychiatric disorders were: attention deficit hyperactivity disorder, 422; depressive disorder, 103; mental retardation, 99; and behavioural disorder, 96. The EEG findings were divided into normal (37.8%) and abnormal patterns (61.9%). The most frequent abnormality was bioelectric immaturity (56.4% of cases). On analysing epileptiform activities, we found 26 studies (2.6%) and evidence of cortico-subcortical irritability in 6.7%. The total number of children with epileptiform patterns was 71. The most common pattern was the sharp wave (97.2%) and the most frequent location was the temporal lobe (42.3%).


CONCLUSIONS
A high percentage of patients with psychiatric disorders also have abnormalities in the electrical activity of their brains, and even epileptiform activity. Electrical abnormalities in the general population of healthy children have been reported in the literature, but the figures that we found are higher for patients with psychiatric disorders. Functioning of the neurons is incorrect and this results in a range of different pathologies. The repercussion of abnormal electrical activity of the brain on the clinical data of the patients is open to discussion, and we consider it to be an epiphenomenon.
Reséndiz-Aparicio
J C
JC
Departamento de Neurología Pediátrica, Hospital Psiquiátrico Infantil Dr. Juan N. Navarro, Tlalpan, México. jc_doc@yahoo.com
Coiscou-Domínguez
N R
NR
Yáñez-Acosta
L
L
Rodríguez-Rodríguez
E
E
Rivera-Quintero
J
J
Aguirre-García
E
E
Cruz-Martínez
E
E
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004827:Epilepsy / Q000150:complications; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000503:physiopathology*; D012189:Retrospective Studies