A REVIEW OF MENTAL RETARDATION AND IT S ETIOLOGIC CAUSES IN CHILDREN BETWEEN 4-15 YEAR OLD REFERRED TO MOFID PEDIATRIC HOSPITAL

Mental retardation in children creates one of the most important for every society. Taking care of menatally retarded child causes many emotional and financial difficulties for the family. Needless to say, the prevention of mental retardation is the keyword in the management of the problem which is feasible in many situations. To acertain the etiologic factors causing mental retardion, all children with Intelligence Quotient (IQ) less than 70, who were referred to Mofid pediatrics hospital during a 9 months period from Mehr 1375 to Khordad 1376 (Sept 1996 – May 1997) constitute the subjects of this investigation. 150 children in the age range of 4 – 15 year old were included in the protocol. Based upon diagnositc studies, mental retardation in 20% of the cases (30 of 150 ) is attributed to prenantal causes, which the most important of them were: Genetic disorders, chromosomal aberration, metabolic diseases and intrauterine infections. In 24% of the cases (36 of 150), mental retardation could be attributed to perinatal causes, like: Brith asphyxia, premature labor, traumatic brith and twin delivery. Among postnatal factors which caused mental retardtion in 27.3% of cases (41 of 150), infections, trauma, intracranial hemorrages and hypothyroidism constituted the most predminant etiologic agents. We could not delineate the causes of mental retardation in 28.7% of the patients (43 of 150). Althogh our patients were in 4 – 15 years age group, but the majority of these children were aged 4 – 5 years. 72% of them had motor developmental delay and 65% suffered from epliepsy. Behavior disorder, visual and auditory impariments and cerebral palsy were aditional findings in mentally handicaped child. 42.7% of our study group were product of consanguineous marriage. Based upon this study it seems that considering the following steps can reduce occurrence of mental retardation to a significant degree. Prevention of premature birth when feasibel, treatment and control of infectious disease, paying more attention to prevention of trauma and accidents, performing screeing test at birth for early diagnosis of some metabolic disease (PKU) and hypothyroidusm and finaly avoiding consanguineous marriage, if any case of mental retardation has happened in the family previously.