** NOT PEER REVIEWED **
In this complex care program, genetic testing often did not provide an answer.
An underlying and unifying genetic diagnosis is often sought by families and providers caring for children with medical complexity. However, little has been published on the types of testing pursued or on the likelihood of discovering a diagnosis in this patient population. This retrospective chart review of children enrolled in a single center complex care program examined the rates and types of genetic testing pursued, the associated costs, the duration of testing, and the likelihood of finding an underlying genetic etiology for the child’s condition. Researchers found that 76% of eligible patients underwent some type of genetic testing. The first-line testing performed was a genome/exome-wide microarray, which was then followed by multiple targeted specific gene sequencing tests. On average, patients underwent 4 unique genetic tests during the study period and the length of the testing period was over 2 years; the average cost was over $4000 for all subjects, and over $8000 for those who did not ultimately received a diagnosis. Despite extensive and costly screening, a genetic etiology was only identified in less than half of patients.
This study highlights the high costs as well as the lengthy duration of investigation for a genetic diagnosis in children with medical complexity; additionally, it offers insight into the likelihood of uncovering a diagnosis in this patient population. The study also suggests that whole exome/genome sequencing, the new frontier of genetic diagnosis, may be more cost effective, less time intensive and more likely to yield a positive result than a targeted sequencing approach. As whole exome sequencing becomes more widely available, further research will be needed to evaluate its impact on discovering an underlying diagnosis in children with medical complexity.
Nicki Brodie, MD Pediatric Chief Resident, St. Christopher’s Hospital for Children
Oei K, et al. Genetic testing among children in a complex care program. Children (Basel). 2017 May 22;4(5). PMID: 28531152