- Etiology/Pathophysiology
- Chromosomal deletion: Deletion of short arm of chromosome 5 (5p-)
- Sporadic mutation (most cases); rarely inherited
- Loss of critical genes on 5p15.2 region
- Clinical Features
- Characteristic high-pitched, cat-like cry in infancy (due to laryngeal abnormalities)
- Craniofacial abnormalities:
- Microcephaly
- Hypertelorism (widely spaced eyes)
- Low-set ears
- Micrognathia (small jaw)
- Round face
- Severe intellectual disability
- Hypotonia in infancy
- Growth retardation
- Congenital heart defects (in some cases)
- Diagnostics
- Clinical diagnosis based on characteristic cry and dysmorphic features
- Confirmed by karyotype analysis or FISH (fluorescence in situ hybridization) showing 5p deletion
- Prognosis
- Most survive to adulthood with supportive care
- Cry typically disappears after infancy
- Lifelong developmental delays and intellectual disability
- Key Association
- “Cri-du-chat” = French for “cry of the cat”
- Think: 5p- = cat cry