While children with cri du chat syndrome are born hypotonic (low muscle tone), they tend to become hypertonic (high muscle tone) as they grow older.Affected infants may have feeding difficulties due to low muscle tone, poor suck, and gastroesophageal reflux disease.Additional symptoms affecting different organ systems of the body can also occur.Most cases are thought arise from spontaneous (de novo) genetic errors very early in embryonic development.Summary Cri du chat syndrome (Cd CS or 5p-) is a rare genetic disorder in which a variable portion of the short arm of chromosome 5 is missing or deleted (monosomic).Symptoms vary greatly from case to case depending upon the exact size and location of the deleted genetic material.Common symptoms include a distinctive cry that resembles the mewing of a cat, characteristic facial features, slow growth, and microcephaly, a condition that indicates that head circumference is smaller than would be expected for an infant's age and sex.
In French, Cri du chat translates into “cry of the cat”.
Distinctive facial features may include an abnormally round or plump (moon) face, a broad nasal bridge, widely spaced eyes (hypertelorism), crossed eyes (strabismus), downwardly slanting eyelid folds (palpebral fissures), vertical skin folds that may cover the eyes’ inner corners (epicanthal folds), low-set ears, and an abnormally small jaw (micrognathia).
Improper alignment of the upper and lower teeth (malocclusion) may also occur.
As affected infants age the face may lose its plumpness and become abnormally long and narrow.
Most affected infants also display some degree of psychomotor and intellectual disability.