Tall stature

 

Tall stature is defined as height above 98th centile (2 SD above the mean).

Referral for tall stature is less common, as this may be more socially acceptable than short stature.

However, rapid growth may raise concern of underlying medical disorder.

 

Cause

– Familial tall stature (commonest, normal height velocity & bone age)

– Constitutional tall stature (increased height velocity in preschool age)

– Obesity

– Endocrine disorders

    GH excess – gigantism/acromegaly

    Pituitary adenoma

    Precocious puberty

    Androgen excess (eg CAH)

    Hyperthyroidism

– Genetic syndromes

    Marfan

    BeckwitheWiedemann Synd

    Klinefelter (XXY)

    Sotos

 

History

– Perinatal history: maternal gestational diabetes, macrosomia/ LGS at birth

– Early feeding (BWS often require NG feeds in neonatal period)

– Early growth in infancy- review previous growth measurements

– Has weight gain been excessive too? BMI increasing with obesity?

– Early onset puberty?

– Any dysmorphism? Body proportion abnormal e.g. long arm span?

– Learning or developmental issues? School performance?

– Any features of intracranial pressure / headaches / visual disturbance?

– Any features of hormonal disorder?

– Family h/o tall stature or endocrine or syndrome diagnosis?

 

Examination

Accurate recording & plotting of height, weight, arm span, pubertal stage (Tanner), and calculate height velocity over 6months.

Disproportionate body segments? Increased arm span? (>5cm than height)

Measure height of parents to calculate mid-parental target height*

Any features of dysmorphism, obesity, goitre

Precocious puberty <8y in girls or <9y in boys

Orchidometry in boys- larger testes in precocious puberty; small firm testes in Klinefelters

Slit lamp exam of eyes- lens dislocation superiorly in Marfans & inferiorly in Homocystinuria

 

Investigations

(Consider if not suspecting familial or obesity)

– T3/T4/TSH, Serum IGF-1 & IGFBP-3, LH, FSH, Testosterone/ Oestrogen, DHEAS, 17OHP, Karyotype

– Bone age estimation by x-ray of left wrist

– Consider MRI brain for pituitary stalk & GH suppression test (oral GTT) if suspecting GH excess

– Consider GnRH (LHRH) test if suspecting precocious puberty

 

Management

Ensure accurate measurements & estimation of height velocity & Mid-Parental Target Height

Reassurance for Familial & Constitutional tall stature

Obesity requires dietary advice to prevent metabolic syndrome & other complications

Precocious puberty may require endocrinology specialist advice but intervention is rare unless pituitary adenoma which may require surgery.