Comprehensive Evaluation of the Child With Intellectual Disability or Global Developmental Delays

Abstract: Global developmental delay and intellectual disability are relatively common pediatric conditions. This report describes the recommended clinical genetics diagnostic approach. The report is based on a review of published reports, most consisting of medium to large case series of diagnostic tests used, and the proportion of those that led to a diagnosis in such patients. Chromosome microarray is designated as a first-line test and replaces the standard karyotype and fluorescent in situ hybridization subtelomere tests for the child with intellectual disability of unknown etiology. Fragile X testing remains an important first-line test. The importance of considering testing for inborn errors of metabolism in this population is supported by a recent systematic review of the literature and several case series recently published. The role of brain MRI remains important in certain patients. There is also a discussion of the emerging literature on the use of whole-exome sequencing as a diagnostic test in this population. Finally, the importance of intentional comanagement among families, the medical home, and the clinical genetics specialty clinic is discussed.

Link to article: https://pediatrics.aappublications.org/content/134/3/e903

PubMed:  https://pubmed.ncbi.nlm.nih.gov/25157020/

Authors: John B. Moeschler, Michael Shevell

Key Terms: Non-CCDS disease, Diagnostic, Basic Science, Pediatric Patient