Noonan Syndrome can be clinically diagnosed if certain findings are present. Identification of an associated genetic defect can confirm the diagnosis.
Parameters:
(1) facial dysmorphology
(2) cardiac defect
(3) short stature
(4) chest wall malformation
(5) family history
(6) 3 other findings (mental retardation, cryptorchidism, lymphatic dysplasia)
|
Parameter |
Finding |
Criteria |
|
facial dysmorphology |
typical |
major |
|
|
suggestive |
minor |
|
|
neither |
none |
|
cardiac defect |
pulmonic valve stenosis, hypertrophic obstructive cardiomyopathy (HOCM), ECG typical for Noonan syndrome |
major |
|
|
other defect |
minor |
|
|
neither |
none |
|
short stature |
below 3 rd percentile for age and gender |
major |
|
|
below 10 th percentile |
minor |
|
|
above 10 th percentile |
none |
|
chest wall malformation |
pectus excavatum or pectus carinatum |
major |
|
|
broad thorax |
minor |
|
|
none |
none |
|
family history |
first degree relative with definite Noonan syndrome |
major |
|
|
first degree relative with findings suugestive of Noonan syndrome |
minor |
|
|
neither |
none |
|
other findings |
all 3 |
major |
|
|
at least 1 of the 3 |
minor |
|
|
none of the 3 |
none |
|
Facial Dysmorphology |
Major |
Minor |
Diagnosis |
|
typical |
>= 1 |
NA |
definite |
|
typical |
0 |
>= 2 |
definite |
|
suggestive |
>= 2 |
NA |
definite |
|
suggestive |
< 2 |
>= 3 |
definite |
where:
• There probably needs to be an additional criteria covering suggestive facial dysmorphology, 1 major nonfacial criteria and >=2 minor.
Specialty: Genetics
