Alternatives to growth hormone stimulation testing in children

Despite more than 40 years of pediatric growth hormone (GH) replacement, we are still limited in our ability to make a definitive diagnosis of GH deficiency (GHD) in children. Historically, GH stimulation tests (GHSTs) have been used to discriminate between GHD and idiopathic short stature. Over the years, increases in the peak diagnostic GH cutoffs and the proliferation of GH assays have fundamentally changed the nature of the GHST. In our opinion, today's GHSTs lack reproducibility and accuracy, are expensive, and can be dangerous. Moreover, newer diagnostic tools, such as high-resolution neuroimaging, measurements of serum insulin-like growth factor 1 and insulin-like growth factor-binding protein 3, and an increasing number of genetic tests, have emerged. We believe that it is no longer appropriate to use GHSTs to diagnose childhood GHD. Instead, diagnosis should be based on a combination of auxological, biochemical, neuroradiological and genetic considerations. Here, we examine the alternatives to the GHST that are currently available and literature that supports their use. We believe that these alternative methods should replace the GHST.