Screening for inborn errors of metabolism among mentally retarded patients. Outcome of a surgery at the Witrand Care and Rehabilitation Centre.

The prevalence of different types of inborn errors of metabolism among the mentally retarded patients at the Witrand Care and Rehabilitation Centre, were determined by means of a biochemical screening survey. These results are compared with those of other surveys in South Africa and abroad. One important result points to substantial differences in the recorded incidences of metabolic defects between surveys. This observation could partially be due to significant differences between the different studies in terms of methodology employed and sampling procedures. The questions raised in this regard are documented and discussed.