Clinical and Genetic Characterization of a Cohort of Small-for-Gestational-Age Patients: Cost-Effectiveness of Whole-Exome Sequencing and Effectiveness of Treatment with GH.

Background/Objectives: Develop a clinical and genetic characterization, in a group of small-for-gestational-age (SGA) patients who did not experience catch-up growth Methods: In an ambispective cohort study with (SGA) patients. These patients received one treatment with growth hormone (GH) over 14 years. This study analyzes their response to treatment and conducts a genetic analysis in order to identify cases with specific phenotypic and auxological characteristics, defined as presenting two or more dysmorphic traits and/or a stature below -3 SDS (standard deviation score). Whole-exome sequencing (WES) was performed on selected patients. Results : Forty-four SGA patients were examined, with an average age of 6.4 (2.49) years and an initial size of -3.3 SDS. The pubertal growth was 24.1 (5.2) cm in boys and 14.7 (4.3) cm in girls. WES in 11 SGA patients revealed conclusive genetic variants in eight, including two pathogenic ACAN variants, one 15q26.2-q26.3 deletion, and four variants of uncertain significance in other genes. Conclusions : Treatment with GH in SGA patients was shown to be effective, with a similar response in the group with positive genetic results and in the group who did not undergo a genetic study. Genetic testing based on auxological and clinical criteria proved highly cost-effective.