Characteristics/Symptoms

Not all people with Noonan syndrome will have all of these features.

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  • May have had surgery and/or be on medications
  • Most common deficit is pulmonary valve stenosis
  • Hypertrophic cardiomyopathy occurs in 20%
  • Lifetime cardiac follow-up is important for all

  • Final adult height approaches lower limit of normal

  • Increase in learning disabilities
  • Increase in brain differences
    • Wide array of neurologic problems
    • Seizures possible
  • Speech articulation difficulties in 72%

  • Broad neck or extra tissue at back of neck
  • Unusual shape to the chest
    • prominence at the top of the breast bone and sunken area at the bottom
    • Nipples wide spaced and low set
    • Rounded shoulders
  • Spinal abnormalities
    • Scoliosis (10-15%)
    • Less common spinal differences such as kyphoscoliosis (hunchback), spina bifida, and changes in vertebrae and ribs
  • Clubfoot 10-15%
  • Ability to hyperextend at the elbow
    • Abnormal forearm angles found in >1/2 males and females.
    • may have leg pain

  • Low set ears
  • Pale blue or blue green irises
    • Iris’ typically lighter in color
  • Wide spaced eyes with epicanthal folds (extra fold at the inner part of the eye lid) and thick or droopy eyelids
  • Lack of affect or expression

  • Problems affecting color and texture of the skin
    • Lotions or short courses of topical steroids help dry skin
    • Avoid long hot baths, perfumed soaps, and dry atmosphere
  • May have curly, coarse, or sparse hair

  • Specific testing will identify the problem and treatment if necessary.
  • May include bruising or nose bleeds, bleeding with surgery
  • Avoid aspirin unless documented that they don’t have coagulation defects

  • Poor bite in 50-66%

  • May be in one area or widespread
  • May be before or after birth
  • Overall incidence in all age groups is 20%
  • Lymphedema in the arms or legs is the most common
    • Typically resolves in first few years of life
    • Adolescents and adults can also develop peripheral lymphedema

  • Strabismus/crossed eyes
  • Refractive errors
  • Amblyopia (lazy eye)
  • Nystagmus (rhythmic movement of the eyes from side to side)

  • Present in  about 11% and are generally minor
  • Kidney swelling is most common

  • Male puberty and fertility may be normal, delayed (about age 13.5-14.5), or inadequate
  • Female puberty may be delayed
    • Mean age of first period is 13-14 years
    • Normal fertility typically