title: Leprechaunism (Donohue syndrome): a case bearing novel compound heterozygous mutations in the insulin receptor gene.
abstract: Leprechaunism (Donohue syndrome) is the most severe type of insulin receptor (INSR) gene anomaly with the majority of patients surviving for only 2 years.  We report a surviving 2 -year-old male with leprechaunism, bearing novel compound heterozygous mutations in the INSR.  The patient is a Japanese boy with acanthosis nigricans, lack of subcutaneous fat, hirsutism, thick lips, gum hypertrophy and extremely high insulin levels (6702 mU/mL).  He was as having identified novel compound heterozygous mutations in INSR (p.T910M and p. E1047K).  At 24 day-old, recombinant human insulin-like growth factor 1 (rh-IGF1) treatment was started because of poor weight gain.  At 2 years old, the patient's serum glucose level and HbA1C value had worsened, and both a bolus of rh-IGF-1 and a subcutaneous injection of a rapid-acting insulin analog after meals, in addition to α-glycosidase inhibitor, were initiated from 2 years onward.  Oxygen administration and biphasic positive airway pressure treatment were also initiated from 2 years old due to upper airway obstruction with adenoidal hypertrophy.  In the experiments conducted using COS7 cells homozygously transfected with the INSR mutation, T910M INSR failed to process the proreceptor and decreased insulin-stimulated tyrosine phosphorylation.  E1047K INSR resulted in a complete absence of insulin-stimulated tyrosine phosphorylation.  These findings suggest the near absence of INSR in this patient.  We consider that the rhIGF1 treatment contributed to his long survival, but it was not able to prevent his diabetic condition.  Our report provides important insights into the function of INSR, and for the treatment of leprechaunism.
authors.affiliation: Division of Pediatrics & Perinatology, Tottori University Faculty of Medicine, Yonago 683-8504, Japan. yuki.kawashima@med.tottori-u.ac.jp
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawashima
authors.forename: Rei
authors.initials: R
authors.lastname: Nishimura
authors.forename: Akari
authors.initials: A
authors.lastname: Utsunomiya
authors.forename: Reiko
authors.initials: R
authors.lastname: Kagawa
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Funata
authors.forename: Masanobu
authors.initials: M
authors.lastname: Fujimoto
authors.forename: Keiichi
authors.initials: K
authors.lastname: Hanaki
authors.forename: Susumu
authors.initials: S
authors.lastname: Kanzaki
mesh_terms: D002675:Child, Preschool; D056731:Donohue Syndrome / Q000188:drug therapy / Q000235:genetics*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007223:Infant; D061266:Insulin, Short-Acting / Q000627:therapeutic use; D007334:Insulin-Like Growth Factor I / Q000627:therapeutic use; D008297:Male; D009154:Mutation; D011972:Receptor, Insulin / Q000235:genetics*; D011994:Recombinant Proteins / Q000627:therapeutic use
chemical_list: D007004:Hypoglycemic Agents; D061266:Insulin, Short-Acting; D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I; D011972:Receptor, Insulin