The case against routine electroencephalography in specific language impairment.
BACKGROUND
Specific language impairment is a primary developmental language disorder in which language is impaired disproportionately to other developmental domains. Electroencephalography is often conducted in the medical investigation of a child with specific language impairment; however, at present, there is uncertainty regarding necessary testing using electroencephalography.


METHODS
The cases of 111 children with the diagnosis of specific language impairment over a 10-year interval, who also underwent electroencephalography, were systematically reviewed in a retrospective manner. Children with a history of previous afebrile seizures, acquired language delay, or documented language regression, developmental delay, hearing loss, coexisting autistic features, and known central nervous system disorders were excluded.


RESULTS
The majority (76%) of the children were boys. Thirty-five (31.5%) children had abnormal electroencephalography results, including 7 (6.3%) children with epileptiform activity. This is higher than the prevalence rate of epileptiform activity in a historical cohort of 3726 (3.54%) children but not statistically significant. The epileptiform activity was deemed active in only 3 of 7 patients and was not related to the specific type of language delay observed. CONCLUSIONS. Although abnormal electroencephalographic activity is seen frequently in children with specific language impairment, epileptiform activity is rare and without apparent impact on clinical care. Awake electroencephalography does not seem to be useful in the routine diagnostic evaluation of young children with specific language impairment, although further investigations of both wake and sleep electroencephalography in this homogenous population must be conducted before definitive recommendations can be made.
Venkateswaran
Sunita
S
Department of aNeurology/Neurosurgery, Montreal Children's Hospital-McGill University Health Center, Montreal, Quebec, Canada.
Shevell
Michael
M
D002675:Child, Preschool; D003937:Diagnosis, Differential; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007805:Language Development Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D008297:Male; D015995:Prevalence; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies; D013997:Time Factors