Download pdf - Tall Stature

7/27/2019 Tall Stature

1/24

Tall StatureDr. Kandi Catherine Muze


2/24

Introduction

As tall stature becomes more prevalent and moreacceptable, referrals, particularly of tall girls, appear tobe decreasing.

The referral of a child with tall stature is frequently theresult of parental concern about actual or future finalheight.

However, knowledge of the pathogenesis, clinical andbiochemical associations and potential treatment of tallstature is clinically relevant.


3/24

Tall Stature

a statue of RobertWadlow, who wascalled the Alton giant.

He was the tallestperson ever recordedand was 8 feet 11inches tall at the time

of his death.


4/24

MacCune Albright Syndrome

Photograph showsa 12-year-old boywith McCune-

Albright syndrome.His growth-hormone excessmanifested as tall

stature, coarsefacial features, andmacrocephaly


5/24

CausesTall stature is usually associated with one of

three etiological categories:

Familial advanced growth;

a syndrome associated with tall stature,

(which has usually been present since

infancy);

abnormal increase in growth rate of

endocrine origin.


6/24

Differential Diagnosis

1. Familial tall stature

2. Syndromes associated with tall stature: chromosomal defects

Klinefelters syndrome

XXXY, XYY syndromes

overgrowth syndromes Soto's syndrome

Weavers syndrome

MarshallSmith syndrome

BeckwithWiedemann syndrome, hyperinsulinism Marfans syndrome

MEN 2B

ACTH resistance

Homocysteinuria


7/24

Differential diagnosis

3. Tall stature of endocrine origin:

GH secreting pituitary tumour

precocious puberty Hyperthyroidism

4. Simple obesity


8/24

Sotos Syndrome

Increased birth length

Increased birth head circumference

Recognizable facies

downslanting eyes

bossed forehead

prominent jaw

Hypotonia, clumsiness

Early puberty

50% need special education

Rare, autosomal dominant inheritance


9/24

Marfans SyndromeAutosomal dominant

Fibrillin gene defect One in 10 000 birthsArm span 8 cm > heightArachnodactyly Skeletal features

kyphoscoliosisjoint laxity pectus excavatum

pes planus High arched palateAortic dilatation, aortic, mitral valve anomalies Myopia, lens dislocation


10/24

Marfans Syndrome

Tall stature

Arm span> Height

Kyphoscoliosis


11/24

Beckwith-Wiedenman Syndrome

Increased birth weight and length

Growth velocity and bone age advanced duringfirst 46 years

Macroglossia

Hemihypertrophy Ear signs

ear lobe creases (see Chapter 2)

pits on pinna

Hypoglycaemia

Omphalocoele

Malignancies (e.g. Wilms tumour)

Learning difficulties


12/24

Assessment Procedure Height, weight, height velocity

Heights of parents, siblings

Birth weight, length, head circumference

History of previous growth, past medical history

Intellectual development

Systematic inquiry


13/24

Assessment

Examination for dysmorphic features

Systematic examination

Pubertal development staging withmeasurement of testicular volume

Bone age and final height prediction


14/24

Baseline Investigation

Karyotype

T4, TSH

IGF-I

Bone age and final height prediction

f


15/24

Investigations for suspected

GH secreting pituitary adenoma.

Glucose tolerance test for GH secretion

MRI scan of pituitary

Visual fields

Cortisol (9.00 a.m.)

Prolactin

Testosterone, LH, FSH (depending on age)


16/24

Treatment of GH secreting Pit tumour

A GH secreting tumour causes tall stature andgigantism in childhood and adolescence, andacromegaly in adult life. An association with

McCuneAlbright syndrome is recognized.

Suppression of GH secretion may requirepituitary surgery, radiotherapy, somatostatinanalogue or GH receptor antagonist therapy.

T t t f f ili l


17/24

Treatment of familial(constitutional) tall stature

Sometimes treatment is indicated to try toslow down growth and reduce the finalheight.

Two forms of therapy are currently used: High dose Sex steroid therapy and

GH suppressive therapy using a

somatostatin analogue.NB: In future, GH receptor antagonist

therapy may be appropriate.


18/24

Sex-steroid therapy

Abnormally high circulating levels will

advance skeletal maturation andeventually cause early epiphyseal fusion.

De Waal et al:

In Girls, ethinylestradiol 100300 mg/day orallycombined with cyclical progesterone (i.e.norethisterone 5 mg/day for days 114 of each

calendar month), if used relatively early,reduced final height by up to 7 cm. In boys,testosterone 2501000 mg monthly caused asimilar reduction.


19/24

Somatostatin analogue therapy

Suppression of GH levels shouldtheoretically slow down growth and ifused on long time basis, may reduce finaladult height.

Hindmarsh et al:use of the somatostatin analogue octreotide ina dosage of 37.550 mg once or twice dailycaused significant decrease in height velocity,with reduction in height prediction of up to 5cm.

NB:Given by SC inj, may cause gastrointestinal side effects


20/24

Controversial Points

The treatment of tall stature in girls iscontroversial.

High dose oestrogen therapy is rarely practisednow. Treatment with a somatostatin analoguemay be effective but is invasive and associatedwith side effects.

New therapy using a GH receptor antagonist ispromising but not yet established to bebeneficial.


21/24

Controversial Points

As tall stature is better tolerated bysociety, there seems to be less indicationfor therapy.

Rare conditions, such as GH secretingpituitary tumours, are very infrequently

seen in paediatric practice. These patientsmust be managed jointly with an adultendocrine unit.


22/24

Potential pitfalls

Failure to consider the diagnosis of orexamine the patient carefully fordysmorphic features suggestive of

Marfans syndrome.

The diagnosis may have seriousconsequences as these patients need life-long cardiovascular surveillance


23/24

Potential pitfalls

Failure to appreciate that tall stature anddelayed puberty are an unusualcombination.

An important differential diagnosis isKlinefelter syndrome, which should be

considered.


24/24

Future developments

Molecular analysis of tall stature andovergrowth syndromes is likely to identifynew genetic causes of these disorders.