title: Laron syndrome (primary growth hormone insensitivity): a unique model to explore the effect of insulin-like growth factor 1 deficiency on human hair.
abstract: BACKGROUND
  Classical Laron syndrome is a recessive disease of primary insulin-like growth factor 1 (IGF-1) deficiency and primary growth hormone insensitivity. Affected children have, among other defects, sparse hair growth and frontal recessions. The hair is thin and easy to pluck. Young adults have various degrees of alopecia, more pronounced in males.
  
  
  OBJECTIVE
  The aim of the present study was to investigate the effect of primary IGF-1 deficiency on hair structure. The study sample included 11 patients with Laron syndrome--5 children (2 untreated) and 6 adults (5 untreated). Hairs were examined by light and electron microscopy.
  
  
  RESULTS
  The most significant structured defect, pili torti et canaliculi, was found in 2 young, untreated patients. Grooving, tapered hair and trichorrhexis nodosa were found in the remainder. IGF-1-treated patients had either none or significantly fewer pathological changes compared to the untreated patients.
  
  
  CONCLUSIONS
  This is the first documentation of the role of primary IGF-1 deficiency on hair structure in human beings.
authors.affiliation: Unit of Pediatric Dermatology, Schneider Children's Medical Center of Israel, Petah Tiqva, Israel.
authors.forename: R
authors.initials: R
authors.lastname: Lurie
authors.forename: D
authors.initials: D
authors.lastname: Ben-Amitai
authors.forename: Z
authors.initials: Z
authors.lastname: Laron
mesh_terms: D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006130:Growth Disorders / Q000473:pathology*; D006197:Hair / Q000473:pathology* / Q000648:ultrastructure; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000172:deficiency* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D013577:Syndrome
chemical_list: D007334:Insulin-Like Growth Factor I