Endocrine Flashcards
Insulin start dose
0.5 units/kg
increase by 1-2 units/kg
DKA diagnosis
blood glucose >11.1
blood ketones >3
metabolic acidosis
DKA management
fluids resuscitation 10ml/kg
sthen slow rehydration over 48hrs
insulin 0.1units/kg/h
watch K+
Congenital hypothyroidism causes
maldescent of thyroid athyrosis dyshormonogenesis iodine deficiency TSH deficiency
Descent of thyroid gland
sublingual position -> larynx
Congenital hypothyroidism clinical features
faltering growth prolonged jaundice constipation coarse facies large tongue umbilical hernia delayed development learning difficulties
Congenital hypothyroidism management
thyroxine from neonatal period
PTH function
increased osteoblast function
if Ca low-> osteoclast activity to release ca and PO
stimulates vit D metabolism
Hypoparathyroidism can be congenital- what is the name of the syndrome
DiGeorge Cardiac abnormalities Abnormal facies Thymus hypoplasia -> cellular immune deficiency Cleft palate Hypoparathyroidism w/ low Ca 22 chromosome
Hyperparathyroidism if presents in late childhood/adulthood, can be part of what syndrome?
MEN 1 and 2a
Term babies should double and treble their weight in what period of time?
Double in 4.5m
Treble in 1 year
Puberty: development order in females
- breast development
- pubic hair and growth spurt
- menarche
Puberty: development order in males
- testicular enlargement over 4ml volume
- pubic hair
- rapid height growth
Short stature define
below 2nd gentile (2SDs below the mean)
Investigation required below which height gentile
0.4 th
Short stature causes
familial
constitutional delay
small for gestational age and extreme prematurity
chromosomal disorders
Gene involved in pathological short stature
Short stature homeobox (SHOX) gene
X chromosome
Short stature investigations
x ray l wrist FBC Creatine (CKD) Calcium, phos, alk phos TSH Karyotyope Anti-endomysial and anti-tissue transglutaminase antibodies CRP GH provocation test IGF-1 levels (GH axis) Morning cortisol and dexamethasone test MRI
Growth hormone treatment indications
GH deficiency Turner syndrome Prader-Willi syndrome CKD SHOX deficiency IUGR/small for gest. age w/o catch up by 4yrs
Tall stature causes
familial/inherited obesity hyperthyroidism XS sex steroids gigantism (XS GH) Syndromes (Marfan, Homocystinuria, Kliengelter, Sotos syndrome)
Development of undifferentiated gonad in fetes into female
absence of SRY gene (Y chromosome)
Development of undifferentiated gonad in fetes into testis in male
SRY (sex determining region on Y chromosome)
anti-Mullerian hormone (inhibits uterus and Fallopian tube development)
testosterone drives external genitalia development and maintains internal genitalia
XS androgens in females
seen in congenital adrenal hyperplasia
causes virilisation in females
inadequate androgens in male
under-virilisation caused by -receptor problem (androgen insensitivity) -5alpha reductase deficiency -abnorm. of synthesis from cholesterol
Congenital adrenal hyperplasia causes…
insufficient cortisol and mineralocorticoid secretion
Congenital adrenal hyperplasia caused by
deficiency in 21-hydroxylase
+/- aldosterone deficiency
Congenital adrenal hyperplasia clinical features
virilisation in females
-> clitoral hypertrophy, fusion of labia
enlarged penis and pigmented scrotum in males
salt-loosing adrenal crisis
tall stature
precocious pubarche
Aldosterone function
salt and water retention
via increased ENaC expression
Congenital adrenal hyperplasia diagnosis
increased-> 17 alpha hydroxy- progesterone
Congenital adrenal hyperplasia: salt loosing crisis management
IV chloride
glucose
hydrocortisone
Congenital adrenal hyperplasia: general management
glucocorticoids (hydrocortisone)
-> ACTH suppression -> normal growth and maturation
mineralocorticoids (fludrocortisone)
monitor growth, skeletal maturity, plasma androgens and 17alpha hydroxy-progesterone and adjust dose
HPA axis
Hypothalamus-> CRH
Ant Pit -> ACTH
Adrenal cortex-> cortisol
Primary adrenal insufficiency (Addison’s disease) diagnosis
Synthacthen test
- normal response excludes adrenal insufficiency
Precocious puberty types
gonadotrophin dependent (central, true)- premature activation of the axis -> normal sequence independent (XS sex steroids outside of pituitary, LH and FSH suppressed) -> abnormal sequence
Female precocious puberty causes
idiopathic/familial*
pituitary adenoma (gonad. dep)*
XS androgens from CAH, adrenal tumours (gonad. independent.)
Female precocious puberty Ix
USS ovaries and uterus
-> progress of puberty
Which type of precocious puberty is common in females and why?
Gonadotrophin dependant
Ovaries are sensitive to LH and FSH
Which type of precocious puberty is common in males and why?
gonadotrophin independent
testes are relatively insensitive to LH and FSH
Male precocious puberty causes
b/l testes enlargement -> gonad. dep cause
- intracration tumour
- liver ca secreting b-hCG
pre-pubertal testes (gonad. independent. cause)
-adrenal pathology
unilateral testis enlargement
- gonadal tumour
Precocious puberty management
gonadotrophin releasing hormone analogue
-> delays onset of menage
Gonadotrophin independent cause
- inhibitors of androgen or oestrogen production or action
-> medroxyprogesterone acetate, cyproterone acetate, testolactone, ketoconazole
Define precocious puberty
<8yrs females
<9yrs males
Define delayed puberty
> 14 yrs females
>15 yrs males (more common)
Delayed puberty causes
constutianal delay low gonadotrophin -systemic disease -pituitary dysfunction -isolated gonadotrophin or GH deficiency -Kallmann syndrome (LH def) -acquired hypothyroidism
high gonadotrophin
- klinefelter’s, Turner’s
- gonadal damage
Delayed puberty management in males
not usually required
oxandrolone
androgenic anabolic steroids
testosterone
Delayed puberty management in females
r/o organic cause
oestradiol
