Fragile X, iron, and neurodevelopmental screening in 8 year old children with mild to moderate learning diYculties

Objective—To examine the value of neurodevelopmental examination, fragile X testing, iron studies, and other screening procedures in children with mild to moderate learning diYculties. Design—A cross sectional case-control study. Subjects—A 34% random sample (n = 130) of children withmild tomoderate learning diYculties born between 01/07/83 and 30/06/84 and resident in North and West Belfast. Controls were 130 children without learning diYculties matched for age and geographical area. Results—The prevalence of mild to moderate learning diYculties in North and West Belfast was 16%; 115 (89%) of the learning diYculties group and 80 (58%) of the control group consented to participate. Children in the learning diYculties group scored significantly lower in neurodevelopmental testing and were more likely to fail their audiometry assessment than controls. Children in the learning diYculties group were also more likely to be anaemic and had lower serum iron and transferrin saturation than controls. No cases of fragile X were identified. Thyroid function tests and urinary amino acids were all within normal limits There were no significant diVerences in anthropometry, head circumference, or formal neurological examinations. Conclusions—Children with learning difficultiesaremorelikelytobeneurodevelopmentally immature and iron depleted than controls. Iron depletion should be aggressively sought and treated. The role for routine assessment for fragile X, thyroid function tests, and amino acid chromatography is doubtful. (Arch Dis Child 1997;76:264–267)