noonan syndrome

NOONAN SYNDROME

T.Kamala Priya T.Gowthami

Case ReportA 3 year old male child was admitted to pediatric

ward with cough, cold and breathlessness of 7 days duration.

Cough was productive, associated with breathlessness which was sudden in onset, progressed to grade 4.

There was history of recurrent respiratory tract infections.

At 7 months of age the child was diagnosed at a private hospital to have a congenital heart disease.

He was the first child born by LSCS to non-consanguinous couple.

What is Noonan Syndrome?Noonan Syndrome (NS) is a relatively common

congenital disease that affects both males and females equally.

This is an autosomal dominant disorder.The history of NS begins with a woman named Dr. Jacqueline Noonan.Dr. John Opitz proposed that Noonan’s Syndrome be given the name because Dr. Jackie Noonan was the first to recognize and describe the condition that occurred in both sexes.

It used to be referred to as the male version of TURNER’S SYNDROME (and is still sometimes described in this way); however, the genetic causes of Noonan syndrome and Turner syndrome are distinct.

IncidenceIt is believed that between approximately 1 in

1,000 and 1 in 2,500 children worldwide are born with NS.

It is one of the most common genetic syndromes associated with congenital heart disease, similar in frequency to Down syndrome.

However, the range and severity of features can vary greatly in patients with NS. Therefore, the syndrome is not always identified at an early age.

TYPESBased on the gene in which mutation has occurred,NS is of 5 types: 1. NS 1 – PTPN 11 – a gene on chromosome 12q24.1

which nc encodes pr otein tyrosine phosphatase SHP- 2.

2. NS 2 – Unknown (autosomal recessive)3. NS 3 – KRAS 4. NS 4 – SOS 1 – a gene that positively regulates

n Ras/MAP kinase Pathway.5. NS 5 – RAF 1- less common type.

CLINICAL MANIFESTATIONSThe clinical features the child would have

Cardio-vascular System: Pulmonary Valvular StenosisSeptal defects- Atrial and VentricularHypertrophic cardiomyopathy

Gastro-Intestinal System :Decreased appetite.Frequent vomiting.Failure to thrive.Intestinal malrotation.

Genito- Urinary System:Cryptorchidism.

Lymphatic System: Posterior Cervical Hygroma.Lymphedema.

Developmental :Intellectual disability.Clumsiness.Motor developmental delayLearning disabilities.Autism,Pervasive developmental disorder can

occur.

Haematologic: Easy bruisingThrombocytopeniaVon- Willebrand Disease.Prolonged Partial thromboplastin timePartial deficiency of Factor VIII, XI, XII.Platelet dysfunction.

Stature and posture:Short statureCervical spine fusionScoliosisPectus Excavatum or Pectus Carinatum.Growth retardationWinging of ScapulaHypotoniaLordosis

Head: Large HeadTriangular faceBroad foreheadShort neckWebbed neckCurly Hair

Eyes:HypertelorismPtosisEpicanthal foldsProptosisRefractive errorsStrabismusNystagmus

Ears:Low Set earsBackward rotated earsThick helix of earIncomplete folding of earsSensorineural deafnessChronic Otitis Media

Mouth and Speech:Deeply grooved philtrumMicrognathiaHigh arched palateDental problemsPoor tongue control

LimbsBluntly ended fingersExtra padding on fingers and toesEdema of the back of hands and tops of feetCubitus valgus.

SkinKeloid formationHyperkeratosisPigmented NaeviConnective tissue disesae