Pituitary- pediatrics Flashcards
Rathkes pouch
Part of pituitary formed from mouth epithelium
Hypothalamus blood supply
Superior hypophysis L artery
Anterior pituitary blood supply
Long portal vein from hypothalamus (tearing)
Short portal vein (from posterior pituitary)
What are the investigatory results of growth hormone deficiency?
Delayed bone age
Low IGF-1
Abnormal response to GH stimulation test
What tests show central thyroid issues?
Low free t3/4
With abnormally normal TSH
Symptoms of low cortisol?
Fatigue
Vomiting
Hypoglycemia
Dilutional hyponatremia
Can be life threatening
Septo-optic dysplasia
Cause of hypopituitarism
Two of three: optic nerve hypoplasia, cerebral dysgenesis, hypopituitarism
Prader Willi
Cause of hypopituitarism
SX: hyperphagia, hypotonia, hypogonadism, hypomentation, obesity
Initially failure to feed/thrive, later reverses because of lack of satiety
Cause: genomic imprinting
Kallman syndrome
Associated with gonadotropin deficiency
Cause: x linked KAL mutation
SX: anosmia (no smell), microphallus,
IX: MRI shows changes to olfactory bulb
Laurence moon Bardet beidl
Rental degradation
Extra digit
Cause of gonadotropin deficiency
Acquired causes of hypopituitarism
Radiation to head (leukemia and brain tumours)
Trauma
Tumours
Craniopharyngioma
Benign pituitary tumor but malignant by position
SX: hydrocephalus, visual field defects, anterior or posterior pituitary defects
Symptoms of hypopituitarism
- Hormonal deficits
- Space lesion effects:
- headaches
- visual field changes
How are height targets estimated for children?
By calculating mid parental heights
Causes of normal variant short stature
- Familial: normal growth velocity/bone age/puberty but
Causes of disproportionate short stature?
Skeletal dysplasia:
achondroplasia: short proximal limbs
hypochondroplasia: milder version
Spinal radiation
Rickets
Prenatal causes of short stature?
IUGR (low birth weight)
can be EARLY (end up short, ie. down's) or LATE (low birthweight but usually normal as adults)
Chromosomal Disorder:
ie. Turner’s Syndrome (screen in short girls)
Postnatal (non-endocrine) causes of short stature?
Malnutrition/chronic disease: ie Celiac’s
Drugs/radiation: ie steroids
Psychosocial: neglect/abuse
Post-natal endocrine causes of short stature?
- Hypothyroid
- Cushing’s Syndrome (exogenous source common)
- GH deficiency
- IGF-1 deficiency (Laron dwarfism)
- IGF-1 resistance
Testing for short stature
- Growth charts
- Midparental height
- CBC & differential, lytes, Cr (rule out dz)
- Celiac screen
- Thyroid screen
- Bone age (wrist xray)
Maybe:
karyotype
serum IGF-1
GH testing
Microphallus
Sign of low gonadotropin or combined hypopituitarism
Do this before giving thyroxine
Assess for ACTH deficiency, because if this is present thyroxine can be very dangerous
Sydromic causes of tall stature
Klinefelter
Marian
Consider this cause in short girls
Turners syndrome
