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Growth curves for Laron syndrome

Z Laron1, P Lilos, B Klinger

  • 1Institute of Pediatric and Adolescent Endocrinology Children's Medical Center, Beilinson Campus, Sackler Faculty of Medicine, Petah Tikva, Israel.

Archives of Disease in Childhood
|June 1, 1993
PubMed

Insights

Growth curves for children with Laron syndrome reveal significant growth retardation from birth, with no clear pubertal spurt. Final heights were notably shorter than average, establishing a model for insulin-like growth factor-I deficiency.

Area of Science:

  • Pediatrics
  • Endocrinology
  • Genetics

Background:

  • Laron syndrome is a rare genetic disorder characterized by primary insulin-like growth factor-I (IGF-I) deficiency.
  • Growth retardation is a hallmark feature, evident from birth and persisting throughout childhood and adolescence.

Purpose of the Study:

  • To construct detailed growth curves for children with Laron syndrome.
  • To establish a reference model for growth patterns in primary and secondary IGF-I deficiencies.
  • To provide a basis for monitoring treatment outcomes in Laron syndrome.

Main Methods:

  • Longitudinal growth measurements (height) were collected from 24 patients (10 boys, 14 girls) with Laron syndrome.
  • Growth data were analyzed across infancy, childhood, and puberty.
  • Upper to lower body segment ratios were assessed.

Main Results:

  • Growth retardation was observed from birth (42-46 cm).
  • Postnatal growth curves deviated significantly from normal trajectories.
  • No distinct pubertal growth spurt was identified in either sex.
  • Final mean height for girls was 119 cm (16-19 years), and for boys was 124 cm (beyond 20 years).
  • Upper to lower body segment ratio exceeded 2 SD above the normal mean.

Conclusions:

  • The constructed growth curves serve as a valuable model for Laron syndrome and other IGF-I deficiencies.
  • These curves are essential for tracking growth in untreated patients and evaluating the efficacy of recombinant IGF-I therapy.

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