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Radioulnar synostosis-developmental delay-hypotonia syndrome

Disease definition

Radioulnar synostosis-developmental delay-hypotonia syndrome, also known as Der Kaloustian-McIntosh-Silver syndrome, is an extremely rare syndrome with synostosis described in about 4 patients to date with clinical manifestations including congenital unilateral radioulnar synostosis, generalized hypotonia, developmental delay, and dysmorphic facial features (long face, prominent nose and ears).


Classification level: Disorder
  • Synonym(s):
    • Der Kaloustian-McIntosh-Silver syndrome
  • Prevalence: <1 / 1 000 000
  • Inheritance: Unknown 
  • Age of onset: Neonatal
  • ICD-10: Q87.8
  • OMIM: 266255
  • UMLS: C2931776
  • MeSH: C538217
  • GARD: 1810
  • MedDRA: -
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