ESPE Yearbook of Paediatric Endocrinology

Brief summary: In this meta-analysis, data of 2030 patients with idiopathic growth hormone deficiency (IGHD) extracted from 25 studies were reanalyzed for reversal of GHD on GH retesting. The reversibility of IGHD varied depending on GH retest cut-offs and testing time-point/age. Higher GH cut-offs and earlier testing resulted in lower GHD reversal rate, but even with a cut-off of 7.7–10 ng/mL the reversal rate was 55%, and retesting before final height revealed also a reversal rate of 48%.

GHD reversal is an important topic in pediatric endocrine health care to protect children and families from unnecessary long-term rhGH treatment and related clinical visits, and to save unnecessary drug costs. Currently, most pediatric endocrinologists use a threshold peak GH value of ~7 ng/mL on stimulation tests to diagnosis GHD in children. Guidelines recommend retesting only after full pubertal development and attaining final height (using a threshold peak GH value then of 3–5 ng/mL). The presented systematic review provides an excellent summary of GHD retesting practices over the last decades.

Two hypotheses have been proposed to explain GHD reversal in children with IGHD: first, maturation of the GH axis related to puberty and exposure to sex hormones; second, false-positive initial GH stimulation tests leading to a false diagnosis of IGHD due to diagnostic inaccuracy of our current GH testing.

Given the high GHD reversal rates after retesting, as presented in several studies and confirmed in this meta-analysis, it is time to rethink our practice with respect to both time of retesting as well as initial test methods and cut-offs. Updated guidelines for the management of patients with IGHD are therefore needed.