Growth and Puberty: Short Stature

Question 1

What is short stature usually defined as?

Answer 1

Height below the second centile

Question 2

How many children are shorter than the 0.4 centile?

Answer 2

Only 1 in 250

These children should be assessed for a cause

Question 3

The rate of growth may be abnormal a long time prior to the child being below the second centile. How can this be identified?

Answer 3

From the child’s height falling across centile lines plotted on a height velocity chart

Question 4

What is a sensitive indicator for growth failure?

Answer 4

Height velocity

Question 5

What is a disadvantage of using height velocity calculations?

Answer 5

They are highly dependent on accuracy of height measurements - tend not to be used outside specialist growth clinics

Question 6

How can the genetic expected height be calculated?

Answer 6

The mean of the father and mother’s height with 7cm added for boy and 7cm subtracted for a girl

The 9th to 91st centile range is given by +and- 10cm for boy and +and- 8.5cm in a girl

Question 7

Most short children have short parents. What is this called?

Answer 7

Familial short stature

- but care should be taken that there is no inherited growth disorder e.g skeletal dysplasia

Question 8

What is constitutional delay in growth and puberty?

Answer 8

A variation of normal growth
Presents as short stature in teenage years due to a delay in onset of puberty
Growth in childhood in lower limits, bone age delayed and onset of secondary sexual development delayed
Final growth height is normal
Usually FH of delayed growth and puberty

Question 9

What percentage of children born small for gestational age or extremely premature, remain short?

Answer 9

About 10%

GH may be needed if insufficient catch up growth by 4 years

Question 10

What chromosomal disorders/syndromes are associated with short stature?

Answer 10

Down syndrome - usually diagnosed at birth
Turner syndrome
Russell-Silver
Noonan
Last 3 may present with short stature and minimal symptoms

Question 11

Nutritional/long term illness is a relatively common cause of abnormal growth. These children are usually short and…

Answer 11

Underweight - their weight is on the same or a lower centile than their height

Question 12

What may inadequate nutrition be due to?

Answer 12

Insufficient food
Restricted diet
Poor appetite associated with long term illness
Increased nutritional requirement from increased metabolic rate

Question 13

What chronic illnesses present with short stature?

Answer 13

Coeliac disease - can have short stature without GI symptoms
Crohn’s
CKD - may be present in absence of a history of renal disease
CF - malabsorption, recurrent infections, increased work of breathing, reduced appetite
CHD - increased work of breathing

Question 14

Children subject to emotional and physical deprivation may be short and underweight and show delayed puberty. What usually happens if placed in a nurturing environment?

Answer 14

Catch up growth

Question 15

What endocrine causes of short stature are there?

Answer 15

Hypothyroidism
GH deficiency
IGF1 deficiency
Steroid excess

Question 16

What typically causes hypothyroidism in children?

Answer 16

Autoimmune thyroiditis

Question 17

How is growth affected in cases of hypothyroidism?

Answer 17

Growth failure
Excess weight gain
May go undiagnosed for many years and lead to short stature

Question 18

When hypothyroidism is treated, what can occur?

Answer 18

Catch up growth occurs rapidly

Often with a rapid entry into puberty - this can limit final height

Question 19

Does congenital hypothyroidism, with treatment result in any abnormality of growth?

Answer 19

No

Question 20

GH deficiency may be isolated or secondary to…

Answer 20

Wider pituitary dysfunction
Pituitary function may be abnormal in congenital mid facial or midline defects or due to a craniopharyngioma (tumour affecting pituitary region), a hypothalamic tumour, trauma, meningitis, cranial irritation

Question 21

How does a craniopharyngioma present?

Answer 21

In late childhood
May cause abnormal visual fields - bitemporal hemianopia as it impinges on optic chiasm
Optic atrophy or papilloedema on fundoscopy

Question 22

What is Laron syndrome?

Answer 22

A condition due to defective GH receptors resulting in GH insensitivity
Patients have high GH levels, but low levels of the downstream active product of GH - IGF1

Question 23

Where is IGF1 produced?

Answer 23

Liver and growth plate

Question 24

Is corticosteroid therapy a potent growth suppressor?

Answer 24

Yes

Question 25

Can some growth suppression be seen even with relatively low doses of inhaled or topical steroids?

Answer 25

Yes

Question 26

Is noniatrogenic Cushing’s syndrome rare in childhood?

Answer 26

Yes

Question 27

Does normalisation of height and weight occur once steroids stopped?

Answer 27

Yes

Question 28

What rare conditions cause extreme short stature?

Answer 28

Abnormalities in the gene called short stature homeobox (SHOX) located on the X chromosome, leads to severe short stature and skeletal abnormalities when present on both copies of gene
In Turner syndrome there is thought to be absence of one SHOX gene

Question 29

How is disproportionate short stature measured?

Answer 29

Sitting height - base of spine to top of head
Subischial leg length - subtraction of sitting height from total height
Limited radiographic skeletal survey to identify the skeletal abnormalities

Question 30

Conditions with abnormal body proportions are rare and may be due to…

Answer 30

Disorders of the formation of bone e.g skeletal dysplasia
- they include achondroplasia and other short limb dysplasias
The back may be short from severe scoliosis or some storage disorders e.g the mucopolysaccharidoses

Question 31

What is achondroplasia?

Answer 31

Normal sized torso, but shorter limbs

Question 32

How is GH deficiency treated?

Answer 32

Biosynthetic GH given by subcutaneous injection, usually daily
It is expensive
Management undertaken at specialist centres
Best response seen in those with most severe GH deficiency

Question 33

What are some other indications for biosynthetic GH ?

Answer 33

Turner syndrome
Prader-Willi syndrome
CKD
SHOX deficiency 
Intrauterine growth restriction or small for gestational age with failure to catch up

Question 34

What investigations should be considered for short stature?

Answer 34

X-ray of left hand and wrist for bone age - some delay in constitutional delay do puberty, marked delay for hypothyroidism or GH deficiency
FBC - anaemia in coeliac or Crohns
Creatinine and electrolytes - CKD
TSH - raised in primary hypothyroidism
Karyotype - Turner syndrome (45XO) and other chromosomal disorders
EMA and anti-tTTG - coeliac disease
CRP and ESR - raised in crohns
Growth hormone provocation test - GH deficiency
IGF-1
Cortisol and dexamethasone suppression test - Cushing’s syndrome
MRI - craniopharyngioma or intracranial tumour