Endo - GH Deficiency Flashcards
What does GH stimulate the release of?
Insulin-like growth factor 1 (IGF-1) by the liver
What is congenital growth hormone deficiency?
Disruption to GH axis at hypothalamus or pituitary gland
What can cause a disruption to the GH axis?
Genetic mutations in GH1 or GHRHR (GHRH receptor) genes
Empty sella syndrome
What is empty sella syndrome?
Pituitary gland is under-developed or damaged
What can cause acquired GH deficiency?
Infection
Trauma
Interventions e.g. surgery
What can occur alongside GH deficiency?
Can be in isolation
or
Combination with other deficiencies e.g. hypothyroidism, adrenal insufficiency or gonadotrophin insufficiency
How does GH deficiency present?
Birth or neonates
- Micropenis
- Hypoglycaemia
- Severe jaundice
Older infants and children
- Poor growth, stopping or severely slowing from age 2-3
- Short
- Slow development of movement and strength
- Delayed puberty
How is GHD investigated?
Growth hormone stimulation test
Measures response to medications that normally stimulate GH release
GH levels are monitored for 2-4 hours after administering to assess response
If GHD positive, poor response to stimulation
What medications stimulate GH release?
Glucagon
Insulin
Arginine
Clonidine
What other investigations are used for GHD and why?
Associated hormone deficiencies e.g. thyroid and adrenal
MRI brain - pituitary or hypothalamus abnormalities
Genetic testing - Turner syndrome, Prader-Willi syndrome
X-ray of wrist or DEXA scan - predict final height and determine bone age
How is GHD treated?
Managed by paediatric endocrinologist
- Daily subcut GH
- Treatment of associated hormone deficiencies
- Close monitoring of height and development
What GH injection is given?
Somatotropin
