The clinical impact of chromosomal microarray on paediatric care in Hong Kong.

Abstract

ObjectiveTo evaluate the clinical impact of chromosomal microarray (CMA) on the management of paediatric patients in Hong Kong.MethodsWe performed NimbleGen 135k oligonucleotide array on 327 children with intellectual disability (ID)/developmental delay (DD), autism spectrum disorders (ASD), and/or multiple congenital anomalies (MCAs) in a university-affiliated paediatric unit from January 2011 to May 2013. The medical records of patients were reviewed in September 2013, focusing on the pathogenic/likely pathogenic CMA findings and their "clinical actionability" based on established criteria.ResultsThirty-seven patients were reported to have pathogenic/likely pathogenic results, while 40 had findings of unknown significance. This gives a detection rate of 11% for clinically significant (pathogenic/likely pathogenic) findings. The significant findings have prompted clinical actions in 28 out of 37 patients (75.7%), while the findings with unknown significance have led to further management recommendation in only 1 patient (p ConclusionThe application of CMA in children with ID/DD, ASD, and/or MCAs in Hong Kong results in a diagnostic yield of ∼ 11% for pathogenic/likely pathogenic results. Importantly the yield for clinically actionable results is 8.6%. We advocate using diagnostic yield of clinically actionable results to evaluate CMA as it provides information of both clinical validity and clinical utility. Furthermore, it incorporates evidence-based medicine into the practice of genomic medicine. The same framework can be applied to other genomic testing strategies enabled by next-generation sequencing.