Cri-du-chat Syndrome
A chromosome 5 deletion disorder with a characteristic high-pitched cry
Quick Facts
- Type: Chromosomal (genetic) disorder
- Cause: Missing part of chromosome 5 (5p)
- Hallmark: High-pitched, cat-like cry in infancy
- Diagnosis: Genetic (chromosome) testing
Overview
Cri-du-chat syndrome, French for "cry of the cat," is a genetic condition caused by the loss of a piece of the short arm of chromosome 5 (the 5p region). It is named for the distinctive high-pitched, cat-like cry that many affected babies make in the first weeks of life.
The syndrome leads to developmental delay, intellectual disability, and characteristic physical features. The severity varies depending on how much of the chromosome is missing. With early support and therapies, many children make meaningful developmental progress, and many people with the condition live into adulthood.
Symptoms
Features differ from person to person but commonly include:
- A high-pitched, cat-like cry in infancy that usually becomes less noticeable with age
- Low birth weight and slow growth
- A small head (microcephaly) and a rounded face
- Wide-set eyes, a small jaw, and low-set ears
- Weak muscle tone (hypotonia) in infancy
- Delayed development and intellectual disability
- Feeding and swallowing difficulties in early life
- Behavioral features such as hyperactivity in some children
The cat-like cry results from changes in how the larynx (voice box) and nervous system develop and tends to fade over time.
Causes
Cri-du-chat syndrome is caused by a deletion of genetic material from the short arm of chromosome 5. The amount of missing material varies and affects how severe the condition is.
- New (de novo) deletion: Most cases result from a random deletion that occurs when the egg or sperm forms, or in early development. These are not inherited.
- Inherited (translocation): A minority of cases occur when a parent carries a balanced chromosome rearrangement that can lead to the deletion in a child.
In most cases, the deletion happens by chance and is not caused by anything the parents did.
Risk Factors
- A parent who carries a balanced chromosome 5 translocation, which raises the chance of an affected child
- A previous child with cri-du-chat syndrome in a family where a parent carries a translocation
Most cases arise from a random deletion with no family history and no identifiable risk factor.
Diagnosis
The diagnosis is often suspected from the distinctive cry and physical features in infancy and confirmed with genetic testing.
- Chromosome analysis (karyotype): Can show a deletion of the 5p region.
- Chromosomal microarray: Detects small deletions and measures how much material is missing.
- FISH testing: A targeted test that can confirm a 5p deletion.
If a deletion is found, testing the parents' chromosomes can show whether a translocation is involved, which is important for genetic counseling.
Treatment
There is no cure for cri-du-chat syndrome, but early intervention and ongoing support help children reach their potential and improve quality of life.
- Early intervention programs: Physical, occupational, and speech therapy support movement, daily skills, and communication.
- Feeding support: Help with feeding and swallowing in infancy, and attention to growth.
- Educational support: Individualized learning plans for intellectual disability.
- Treating associated problems: Managing any heart, vision, hearing, or orthopedic issues that arise.
A coordinated team of specialists and family support are key to long-term care.
Prevention
Cri-du-chat syndrome usually cannot be prevented because most cases result from a random chromosome deletion. Families can take informed steps:
- Genetic counseling, especially if a parent carries a chromosome translocation or there is a previous affected child
- Prenatal testing options can be discussed for families at higher risk
When to See a Doctor
See a pediatrician if a baby has an unusually high-pitched cry, poor growth, weak muscle tone, or delayed development. Early evaluation allows prompt referral for genetic testing and supportive therapies. Seek emergency care if an infant has trouble breathing, severe feeding difficulty with choking, or fails to gain weight despite feeding.
Families affected by the condition should consider genetic counseling when planning future pregnancies.
Frequently Asked Questions
Why is it called cri-du-chat syndrome?
The name is French for "cry of the cat" and refers to the distinctive high-pitched, cat-like cry many affected infants make. The cry results from differences in the larynx and nervous system and usually becomes less noticeable as the child grows.
Is cri-du-chat syndrome inherited?
Most cases happen by chance from a random deletion of chromosome 5 material and are not inherited. A minority occur because a parent carries a balanced translocation that can be passed on, which genetic testing can identify.
What is the outlook for a child with cri-du-chat syndrome?
Severity varies with the size of the deletion, but most children have intellectual disability and developmental delay. With early therapies and support, many make steady progress and live into adulthood.
How is cri-du-chat syndrome diagnosed?
It is usually suspected from the cry and physical features and confirmed with genetic testing such as a chromosome analysis or chromosomal microarray, which detect the missing piece of chromosome 5.
Can the syndrome be detected before birth?
It can sometimes be identified through prenatal genetic testing, particularly in families known to be at higher risk. Genetic counseling can explain the available screening and diagnostic options.
References
- MedlinePlus Genetics, U.S. National Library of Medicine. Cri-du-chat syndrome.
- National Organization for Rare Disorders (NORD). Cri du Chat Syndrome.
- Genetic and Rare Diseases Information Center (GARD). Cri du chat syndrome.
- Centers for Disease Control and Prevention (CDC). Birth Defects.