Cri du Chat Syndrome Flashcards
A 3-month-old female is brought to the pediatrician for a follow-up after concerns were raised during her neonatal evaluation. The parents report that the baby has a weak, high-pitched cry that sounds like a cat meowing. Physical examination reveals microcephaly, hypertelorism, epicanthal folds, low-set ears, and micrognathia. The infant also has feeding difficulties and is not meeting developmental milestones. Genetic testing reveals a chromosomal deletion.
What is the most likely diagnosis, and which chromosomal abnormality is associated with this condition?
A. Trisomy 21, an extra copy of chromosome 21
B. Cri du Chat syndrome, deletion on the short arm of chromosome 5
C. Turner syndrome, loss of an X chromosome
D. Edwards syndrome, trisomy 18
E. Angelman syndrome, deletion on maternal chromosome 15
Correct Answer: Cri du Chat syndrome, deletion on the short arm of chromosome 5
Explanation: Cri du Chat syndrome is caused by a deletion on the short arm of chromosome 5 (5p deletion). It is characterized by a high-pitched, cat-like cry in infancy due to laryngeal and neurological abnormalities. Additional features include distinctive facial characteristics (microcephaly, hypertelorism, epicanthal folds, low-set ears, micrognathia), feeding difficulties, global developmental delays, and intellectual disability. Genetic testing, such as fluorescence in situ hybridization (FISH), confirms the diagnosis.
Incorrect Answers:
A. Trisomy 21: Associated with Down syndrome, which presents with flat facial profile, epicanthal folds, and intellectual disability, but not a cat-like cry. C. Turner syndrome: Found in females with a missing X chromosome, associated with short stature, webbed neck, and primary amenorrhea, but not the described features. D. Edwards syndrome: Trisomy 18 presents with overlapping fingers, rocker-bottom feet, and severe intellectual disability, but does not involve a cat-like cry or 5p deletion. E. Angelman syndrome: Characterized by inappropriate laughter, ataxia, and intellectual disability due to a maternal chromosome 15 deletion, not the features described here.
What is the genetic cause of Cri du Chat syndrome?
Cri du Chat syndrome is caused by a deletion on the short arm of chromosome 5 (5p deletion).
What is the hallmark clinical feature of Cri du Chat syndrome in neonates?
The hallmark feature is a high-pitched, cat-like cry in neonates due to laryngeal and neurological abnormalities.
What are the characteristic facial features of Cri du Chat syndrome?
Facial features include microcephaly, hypertelorism (widely spaced eyes), epicanthal folds, low-set ears, and a small jaw (micrognathia).
What are the developmental and intellectual outcomes in Cri du Chat syndrome?
Patients typically have global developmental delays, intellectual disability, and delayed speech and motor milestones.
What is the typical growth pattern seen in Cri du Chat syndrome?
Patients often have low birth weight, failure to thrive, and postnatal growth retardation.
What are the common behavioral characteristics in Cri du Chat syndrome?
Behavioral characteristics may include hyperactivity, self-injurious behavior, and repetitive movements.
What are the potential complications of Cri du Chat syndrome?
Complications include feeding difficulties, recurrent respiratory infections, scoliosis, and congenital heart defects.
How is Cri du Chat syndrome diagnosed?
Clinical presentation
Plus
Diagnosis is confirmed with cytogenetic analysis or fluorescence in situ hybridization (FISH) to identify the 5p deletion.
What is the management strategy for Cri du Chat syndrome?
Management includes supportive care, early intervention programs, speech and physical therapy, and treatment of associated medical conditions.
What is the prognosis for patients with Cri du Chat syndrome?
With appropriate care, most patients survive into adulthood, although they often have significant intellectual and physical disabilities.
