Cri-du-chat syndrome, also known as cat's cry syndrome and 5p- syndrome, is a genetic condition that causes infants to let out a high-pitched cry that sounds similar to that of a cat crying. Cri-du-chat is a French phrase that, in English, means "cat’s cry."
This rare condition is typically seen in only 1 of 15,000 to 50,000 babies around the world.
What Causes Cat’s Cry Syndrome?
Chromosome 5 is one of the 23 pairs of chromosomes seen in human beings. Cat’s cry syndrome is caused by a missing piece of genetic material from a part of chromosome 5 called the p arm. This is why cat's cry syndrome is also called 5p- syndrome.
Only 10% of people with cat’s cry syndrome develop the condition by inheriting the chromosome with the missing part from a parent who isn’t affected by the condition itself. The vast majority of people affected by the condition get it randomly when the eggs or sperm cells are being formed or while the fetus is growing inside the uterus.
The symptoms, signs, severity, and development of the condition depend on the size and the location of the missing genetic piece. Symptoms can vary from person to person and can include:
- A high-pitched cat-like cry
- Mental disability
- Delayed development
- Distinctive facial features
- Microcephaly (small head size)
- Hypertelorism (widely-spaced eyes)
- Low birth weight and hypotonia, or weak muscle tone, in infancy
- Issues with behavior
Other symptoms seen in newborn babies. Babies who have cat’s cry syndrome can also have difficulties with feeding and breathing. Sometimes, they may have problems with the way the heart functions and may need to get surgery. Other symptoms include not being able to suckle properly, needing to be placed in an incubator for care, respiratory distress, jaundice, pneumonia, and dehydration.
Other symptoms seen in children. Children who have cat’s cry syndrome may also have:
- Malocclusion of the teeth
- Short third-fifth metacarpals
- Upper respiratory tract infections
- Otitis media
- Severe constipation
People with cat’s cry syndrome experience difficulties with language and communication. About half learn enough skills to communicate verbally. These can include short sentences. Other patients communicate using basic words, by making movements with their hands, or through sign language.
People who have the syndrome, despite the difficulties, are seen to be happy and friendly and enjoy engaging with others.
Cat’s cry syndrome is usually diagnosed in the hospital at the time of birth. Your health care provider may note the symptoms usually seen in this condition, especially the cat-like cry which is unique to the syndrome. The condition can also be diagnosed while the baby is in the womb through amniocentesis, which can show you that there is a missing part in chromosome 5.
Typical lab tests that may be performed include:
- Conventional cytogenetic studies
- High-resolution cytogenetic studies
- Fluorescence in situ hybridization (FISH)
- Microarray CGH
- Chromosome comparative genomic hybridization (CGH)
- Single-nucleotide polymorphism (SNP)–based prenatal test
- Imaging studies such as skeletal radiography, magnetic resonance imaging (MRI), and echocardiography
There's no specific treatment presently available for cat's cry syndrome. Instead of treatment, those who have cat’s cry syndrome benefit from ongoing support from a team that includes their parents, therapists, and specialists. Some of the specialists who may be able to offer support include:
- Medical geneticists
- Physical therapists
- Occupational therapists
- Speech therapists
- Ear, nose, and throat (ENT) specialists
- Behavior or development specialists
As stated, the outlook of the condition depends on the size and location of the missing piece of chromosome 5. Deaths related to the syndrome take place in 75% of infants during their first month of life, and 90% of babies during the first year. Early diagnosis is critical. The right support early on can help babies with cat's cry syndrome achieve as much as they are capable of and experience satisfying lives.
For a newborn baby, it's advised to start physical therapy in the first week of life to help them with any difficulties they have with suckling or swallowing. It may help the baby breastfeed and intensive care may not be needed. Long-term support includes a combination of educational, physical, and language therapy. These go a long way to help the patient develop physically and improve their psychomotor and social skills.
While cat’s cry syndrome can be life-threatening to babies, most people who are born with this condition can achieve normal life expectancy.