Flashcards in Endocrine Deck (24):
Primary causes of short stature (intrinsic growth plate abnormalities)?
Genetic: downs, prader-willi, noonan, turner, silver-russell
IUGR with failure to catch up:fetomaternal factors, prematurity, placental dysfunction
Congenital bone abnormality: achondroplasia-AD condition with mutation of fibroblast GF receptor 3 gene,hypochondroplasia, osteogenesis imperfecta.
examples of secondary growth disorders responsible for short stature (growth plates change as a result of the condition)?
GH deficiency or insufficiency
laron's syndrome-GH insensitivity
hypothalamic or pituitary lesions e.g. trauma or tumour
disorders of GH insulin-like GF1 axis
medication: corticosteroid excess
metabolic: glycogen storage disease
chronic disease: CVS, Resp e.g. CF, chronic renal failure, malignancy, neurological e.g. hydrocephalus
malnutrition e.g. IBD, coeliac, anorexia, enzyme deficiencies
psychosocial deprivation including hyperphagic short stature syndrome, failure to thrive
physiological causes of short stature?
constitutional short stature (normal variant and often familial)-short parents have short children
maturational delay (often familial)-delay in physical development-late developers
what important genetic cause of short stature should be considered in girls?
should do karyotyping
how should a child's height relate to their parent's height?
normally falls on centile between the parents' height centiles
usefulness of a wrist X-ray in investigating a child with short stature?
can determine bone age:
if delayed, suggests maturational delay, hypothyroidism, GH deficiency or corticosteroid excess.
can make prediction of adult height from it.
when would the mid-parental height be unreliable?
if parents' heights are very different
how is expected final height calculated?
which children does NICE recommend the use of somatotropin (GH) to treat short stature?
small for gestational age with subsequent growth failure at 4 years or later
have short stature homeobox-containing gene (SHOX) deficiency
permanent neurological complications of hypoglycaemia?
severe learning difficulties
tests to perform when hypoglycaemia is present?
blood: confirm hypo with lab blood glucose
GH, IGF-1, cortisol, insulin, C-peptide, FAs, ketones, glycerol, branded-chain amino acids, acylcarnitine profile, lactate, pyruvate
1st urine after hypo:
organic acids, consider saving blood and urine for toxicology e.g. salicylate, sulphonylurea
causes of hypoglycaemia beyond immediate neonatal period?
insulin excess-excess exogenous, beta cell tumours/disorders-insulinoma, persistent hypoglycaemic hyperinsulinism of infancy (PHHI), drug-induced, AI, beckwith syndrome
without hyperinsulinaemia-liver disease, ketotic hypoglycaemia of childhood, inborn errors of metabolism e.g. glycogen storage disorders-suspect if hepatomegaly, hormonal deficiency-GH, ACTH, addison disease, CAH**
when MUST a blood glucose be checked?
if child becomes septicaemic or appears seriously ill
develops an altered state of consciousness
how is premature sexual development defined?
development of secondary sexual characteristics in girls below 8 years of age and boys below 9 years of age
causes of precocious puberty in girl (secondary sexual characteristics develop early with growth spurt)?
most commonly familial or idiopathic (both are gonadotropin dependent), following normal sequence of puberty
organic causes assoc. with:
dissonance-abnormal sequence of pubertal changes, suggesting androgen excess from CAH or an androgen secreting tumour
neurological signs and symptoms e.g. neurofibromatosis
what investigation is helpful in deciding the cause of precocious puberty in girls?
US of ovaries and uterus:
in premature onset of normal puberty, multicystic ovaries and an enlarging uterus will be seen
causes of precocious puberty which are gonadotropin indepenedent (low FSH and LH)?
adrenal disorders-tumours, CAH
ovarian-tumour (granulosa cell)
testicular-tumour (leydig cell)
exogenous sex steroids
causes of precocious puberty which are gonadotropin dependent (both LH and FSH high, LH more so)?
CNS abnormalities-congenital anomalies e.g. hydrocephalus, acquired e.g. post-irradiation, infection, surgery, or tumours e.g. microscopic hamartomas
causes of precocious puberty in males?
this is uncommon
usually organic cause, part. intracranial tumours
testes examination may be helpful:
bilateral enlargement suggests gonadotropin release, usually from an intracranial lesion
small testes suggest adrenal cause e.g. tumour or adrenal hyperplasia
unilateral enlarged testis suggests a gonadal tumour
best investigation for hypothalamic tumours that may cause precocious puberty?
what disease are children who develop premature pubarche (adrenarche) at risk of developing in later life?
what other conditions should premature adrenarche be distinguished from?
late-onset CAH or an adrenal tumour
can obtain a urinary steroid profile to help differentiate
cause of prader-willi syndrome?
deletion on paternal chromosome 15 (on maternal would cause angelmann syndrome)