Endocrine disorders of development and growth Flashcards
when do individuals need further assessment of growth
Where weight or height or BMI is below the 0.4th centile, unless already fully investigated at an earlier age.
If the height centile is more than 3 centile spaces below the mid-parental centile.
A drop in height centile position of more than 2 centile spaces, as long as measurement error has been excluded.
why is monitoring heigh and weight important
Monitoring height and weight is useful to identify disorders affecting growth
what are the requirements for normal human growth
- Absence of chronic disease
- Emotional stability, secure family environment.
- Adequate nutrition
- Normal hormone/growth factor actions
- Healthy growth plates.
what 4 aspects to you use to evaluate short stature
- heigh centile versus weight centile
- when it started
- body proportions
- presenting signs
describe the 4 aspects that you use to evaluate short stature
- Height centile vs weight centile.
• Failure to thrive vs failure to grow.
2. When started. • In utero • In infancy • In childhood • In puberty
- Body proportions.
• Primary or secondary growth disorder - Presenting signs.
• Idiopathic
what are the phases of growth in the ICP model and what causes the growth
Infancy: rapid growth (nutritionally determined, up to two years).
Childhood: relatively steady (primarily regulated by GH and T4).
Puberty: acceleration and then cessation (GH, sex steroids, T4).
How do you calculate height velocity
- Serial height
- Plotted over time
what is a primary growth disorder
Primary growth disorders include clinically-defined syndromes such as Turner’s and Cornelia de Lange, children who are small for gestational age (SGA) with failure to catch up, and skeletal dysplasias.
what is a secondary growth disorder
A secondary growth disorder is a condition where there is an identifiable cause. Examples include: Disease e.g. disorder of the pituitary gland. Hormonal issues e.g. growth hormone deficiency.
What an cause disproportionate growth
Skeletal dysplasia
- achondroplasia
- hydrochondroplasia
- leri-welli dyschonrosteosis
rickets - caused by Vitamin D deficiency
List three types of skeletal dysplasia
- achondroplasia
- hydrochondroplasia
- leri-welli dyschonrosteosis
how do you know the body portions are disproportions
- calculate Standard deviation difference
Subiscial length SDS
LESS
Sitting height SDS
Followed by skeletal survey: Skull Spine Pelvis Upper limb Lower limb
what is the equation for the standard deviation score
SD = measurement - mean / SD at relevant age
What are the three classification of limb shortening
- rhizomelic
- mesmeric
- acromelic
what mutation causes achondroplasia
FGFR3 Mutations
= autosomal dominant
what does achondroplasia do
- Inhibits ossification at growth plates
- Lack of long bone elongation
what is the mutation in hypochondroplasia
Also caused by mutations in FGFR3 other than the 1138 position.
describe characteristics of hypochondroplasia
Affects structure and function of receptor
Features milder than achondroplasia:
- Short stature noticed later
describe the genetics of leri-weill dyschondrosteosis
- it is an autosomal dominant skeletal dysplasia
describe the characteristics of leri-weille dyschondrosteosis
Mesomelic (mid parts) limb shortening
Reduced subischial length
Madelung deformity of the forearm
- Bowing of the radius
- Dorsal dislocation of the ulna
- Premature epiphyseal fusion
what does madeulung deformity consist of
- Bowing of the radius
- Dorsal dislocation of the ulna
- Premature epiphyseal fusion
who has madeulung deformities
Present in
50-74% of LWD
3-7% of Turners
1-3% of Idiopathic Short Stature
what is the most important cause of short stature in humans
SHOX Haploinsufficiency/Phenotypes
• Most important monogenic cause of short stature in humans.
o Found in 1:1000.
• Wide range: idiopathic short stature and LWD.
what can cause propionate growth failure
- psychosocial assessment = psychical growth retardation
- Syndrome features karyotypes = such as turners syndrome, Noonan, Williams
- tests for systemic disorders = such as chronic renal insufficiency, gastrointestinal disease, nutritional deficiency
test for endocrine disorder s= hypothyroidism and hypercortisolism
