Cri du chat syndrome/ Lejeune syndrome/ 5p minus syndrome/ Cat cry syndrome/ Chromosome 5p deletion syndrome.
Incidence
The cri-du-chat syndrome appears to be one of the most common human deletion syndromes, with an incidence varying between 1 in 20,000 to 1 in 50,000 births. The syndrome is familial and is transmitted as an autosomal dominant trait. (Updated August 2017 by MGJM)
Clinical Characteristics
Cri du Chat Syndrome, a rare chromosomal disorder that is apparent at birth, is characterized by a distinctive high, shrill, mewing, \\\\\\\"kitten-like\\\\\\\" cry during infancy. This distinctive cry can become less pronounced during late infancy. Other findings and symptoms may include low birth weight and failure to grow at the expected rate (failure to thrive); distinctive abnormalities of the head and face (craniofacial area) including an unusually small head (microcephaly), widely spaced eyes (ocular hypertelorism), and an unusually small jaw (micrognathia) and mental retardation. Cri du Chat Syndrome is caused by the absence of genetic material (deletion) on the short arm (p) of chromosome 5. Cri-du-chat syndrome is characterized in young children by microcephaly, round face, hypertelorism, micrognathia, epicanthal folds, low-set ears, hypotonia, and severe psychomotor and mental retardation. One of the most characteristic features in newborn children is a high-pitched cat-like cry that is usually considered diagnostic for the syndrome. However, a family has been described in which the characteristic cat-like cry was present without the morphologic features and in which the deletion was confined to 5p15.32. Although the majority of patients die in early childhood, some survive into adulthood and exhibit an IQ below 20, a loss of hypertelorism and epicanthic folds, and development of a thin, narrow face with prominent nasal bridge. Deletion of the short arm of chromosome 5 characterized by a variable clinical picture consisting of severe mental deficiency, growth retardation, multiple abnormalities and a peculiar crying sound resembling that of a suffering kitten (hence the synonym crying cat syndrome or cri du chat syndrome), that disappears within weeks or months after birth.
Precipitants
None
Provocation Tests
None
Diagnostic Procedures
Karyotype. Cri du Chat Syndrome is caused by the absence of genetic material (deletion) on the short arm (p) of chromosome 5.