Cat’s cry syndromePrader-Willi syndromeMohd Nasiruddin Mansor

It was first described by Jérôme Lejeune in 1963

•Cat’s cry syndrome(Cri du chat syndrome/5p- syndrome/Lejeune’s syndrome)

A rare genetic disorder due to a missing part (deletion) of chromosome 5.

Affects 1 in 50,000 live births, strikes all ethnicities

More common in females by a 4:3 ratio

•Overview

-infants produce a high-pitched cry

-also carries many disabilities and abnormalities.

-some are born with serious organ defects or complications that can result in death

-Most fatal complications occur before a child’s first birthday.

Most cases of cri-du-chat syndrome are not inherited

The deletion occurs most often as a random event

•Can cri-du-chat syndrome be inherited?

• A high-pitched cry(abnormal larynx development and CNS )• Low birth weight• Feeding problems• Severe cognitive, speech, and motor delays• Behavioral problems

•Symptoms

• Small chin• Unusually round face• Small bridge of the nose• Abnormally wide-set eyes (ocular or orbital hypertelorism)

• Hypotonia • Low-set ears• Short fingers• Single palmar creases• Cardiac defects (eg, ventricular septal defect)

•SymptomsCommon findings

• Severe mental retardation • Dropped-jaw, open-mouth expression• Malocclusion of the teeth • Scoliosis • Chronic medical problems(URTI,OM,constipation…)• Cleft lip and palate

•Other symptoms

•A-8 months

•B- 2 years

•C- 4 years

•D- 9 years 6 months

•Diagnosis• at birth, based on physical abnormalities and

displayed symptoms.

• X-ray on head to detect abnormalities in the base of the skull

• MRI,CT,EchoCG

• To confirm a diagnosis, a chromosome test often will be performed.

•DiagnosisFluorescence in situ hybridization (FISH)

• Patau syndrome(Trisomy- 13)

•Differential diagnosis

• Wolf-Hirschhorn syndrome(partial deletion of chromosome 4)

• No cure is available for cri-du-chat syndrome

• Speech therapy

• Behavior modification programs

• Surgical treatment(cleft palate,congenital heart problems)

•Treatment

o A rare, genetic disorder

o Seven genes on chromosome 15 (q 11–13)are deleted or unexpressed on the paternal chromosome.

o first described in 1956 in Swiss

o 1 in 10,000 live births.

•Prader-Willi syndromeP.W

•GeneticsChromosome 15

• An individual without Prader-Willi syndrome receives a chromosome 15 from the mother and another from the father.

• In Prader-Willi syndrome there are three genetic subtypes: deletion, maternal disomy and imprinting defect.

•Genetics1.Deletion(70%)

• A deletion including the q12 band

• The imprinted q11-q13 is normally active on the father's chromosome 15 and inactive on the chromosome 15 inherited from the mother. 

• Therefore, the paternally expressed genes from this region of chromosome 15 are missing in the deleted region of chromosome 15 and Prader-Willi syndrome occurs.

• both chromosome 15s are inherited from the mother and no chromosome 15 is present from the father.

• missing chromosome 15 from the father which contains the active genes required for normal development.

•Genetics2. Maternal Disomy or UPD (25%)

• imprinting defect inherited from the father of the chromosome 15 involving the q11-q13 region.

• normal expression of genes that are active on the chromosome 15 from the father is not allowed

• Prader-Willi syndrome then occurs

•Genetics3. Imprinting defects

1)Infants:• Poor muscle tone(hypotonia)• Distinct facial features• Failure to thrive.(poor feeding)• Lack of eye coordination (strabismus)• Generally poor responsiveness(tired,slow response)

•Signs and SymptomsGenerally occur in 2 stages

• narrow temples,elongated face, thin upper lip and a prominent nose.

2)Early childhood• Food craving and weight gain• Underdeveloped sex organs• Poor growth and physical development.(low muscle mass)• Learning disabilities.• Delayed motor development.• Speech problems.• Behavioral problems. • Scoliosis.

•Signs and symptoms2nd Stage

A -8 month female hypotonia, hypogonadism, and need for assisted feedingB- 19 year old obese male C- 34 year old male(with controlled diet)

•Diagnosis

•Based on clinical presentation•Genetic testing

•No cure•Treatment is to lessen the symptoms.• Physiotherapy during infancy•Speech therapy•Growth hormone therapy•They have high pain tolerance-may unaware of acute gastritis,cholecystitis and appendicitis.

•Treatment