Comparison of children with bioinactive growth hormone, small for gestational age, and idiopathic short stature

Esma Kaya Özdemir1, Esra Döğer1, M Orhun Çamurdan1

  • 1Gazi University Faculty of Medicine, Department of Child Health and Diseases, Department of Pediatric Endocrinology, Ankara, Türkiye.

Frontiers in Endocrinology
|September 29, 2025
PubMed

Insights

Children with bioinactive growth hormone (GH) show a distinct, highly responsive subgroup to recombinant human GH therapy. This condition, characterized by ineffective GH, leads to significant growth improvements and normal stature achievement.

Area of Science:

  • Pediatric endocrinology
  • Genetics and molecular biology
  • Growth disorders

Background:

  • Short stature affects numerous children, with rare growth hormone (GH) function disorders being a significant cause.
  • Bioinactive GH, defined by immunoreactive but biologically ineffective GH, represents a specific phenotype within short stature.
  • Understanding the treatment response in different short stature subgroups is crucial for effective management.

Purpose of the Study:

  • To compare the growth response to recombinant human GH (rhGH) therapy in children with bioinactive GH versus those born small for gestational age (SGA) and idiopathic short stature (ISS).

Main Methods:

  • Retrospective, single-center study analyzing medical records of short-statured patients (height ≤ -2 z-score) with normal peak GH response to stimulation tests.
  • Exclusion of patients with chronic illnesses, malnutrition, syndromic/endocrine disorders, or prior pubertal suppression.
  • Inclusion of eligible patients meeting definitions for bioinactive GH, SGA, or ISS.

Main Results:

  • Bioinactive GH patients (n=8) had significantly lower baseline IGF-1 and IGFBP-3 levels compared to SGA (n=27) and ISS (n=74) groups (p < 0.001).
  • Despite similar rhGH doses, bioinactive GH patients showed superior gains in growth velocity and height z-score.
  • All bioinactive GH patients achieved normal final height, surpassing target height, unlike fewer SGA and ISS patients.

Conclusions:

  • Children with bioinactive GH represent a distinct, highly treatment-responsive subgroup within non-GH deficient short stature.
  • IGF-1 generation testing is highlighted as diagnostically valuable for identifying this subgroup.
  • Further multicenter studies are needed to confirm findings and establish international diagnostic guidelines.
Abstract

Related Concept Videos

Nature and Nurture01:10

Nature and Nurture

Many human characteristics, like height, are shaped by both nature—in other words, by our genes—and by nurture, or our environment. For example, chronic stress during childhood inhibits the production of growth hormones and consequently reduces bone growth and height. Scientists estimate that 70-90% of variation in height is due to genetic differences among individuals, and 10-30% of variation in height is due to differences in the environments that individuals experience,...
22.2K
Pharmacokinetics in Pediatric Patients: Drug Metabolism01:24

Pharmacokinetics in Pediatric Patients: Drug Metabolism

In pediatric care, understanding the nuances of hepatic drug metabolism is crucial, as it significantly differs from that of adults. This divergence is primarily due to the developmental stage of drug-metabolizing enzymes, which affects how medications are processed in the body. In neonates, for instance, the activity of Phase I enzymes—critical for the initial breakdown of drugs—is markedly reduced, functioning at just 20–40% of the levels seen in adults. This reduction poses...
193
Polygenic Traits01:18

Polygenic Traits

When more than one gene is responsible for a given phenotype, the trait is considered polygenic. Human height is a polygenic trait. Studies have uncovered hundreds of loci that influence height, and there are believed to be many more. Due to the high number of genes involved, as well as environmental and nutritional factors, height varies significantly within a given population. The distribution of height forms a bell-shaped curve, with relatively few individuals in the population at the...
68.9K