endocrine disorders Flashcards
how are these disorders classified?
- congenital
- failure of full maturation at puberty
- acquired
-> only detected when there are problems conceiving
what causes androgen insensitivity syndrome?
- occurs in males
- insensitivity of fetus to androgens (T)
- leads to wolffian duct degeneration and are Born with female external genitalia
- mutations to the AR
what do patients with a 5-AR mutation present with?
- sexual ambiguity at birth
- appear female
- genetically male (46XY)
what causes kallmann syndrome?
- failure of the migration of GNRH secreting neurons to the hypothalamus during development
what are the main risk factors for precocious puberty?
- -> idiopathic (unknown)
- -> environmental or endocrine disruptors
- -> obesity (estrogen secretion from adipocytes)
- > peripheral, atypical hormone production ( adrenal hyperplasia) or tumours
what characterises delayed puberty?
–> absence of SSC by 14 years (girls) or 16 yrs (boys)
define the key terms
normal menstrual cycle
Amenorrhea
Oligomennorrhea
–> 28-32 days
–> absence of menstrual cycles > 6 months
–> cycles are irregular (<9 year)
what are the signs of adult endocrine disorders?
- oligomenorrhoea or AM
- infertility
- estrogen deficiency (hot flushes, libido)
- hyperandrogenism
- hirsutism, acne, alopecia (baldness)
- galactorrhea
what hormones do we test for diagnostically?
- FSH / LH–> days 2/3 tells us the ovarian reserve
- progesterone at day 21 to tell us ovulation
( compare these values to normal values on axis)
what are the signs of premature ovarian failure?
- amenorrhea
- low oestrogen levels
- high FSH/LH (loss of -ve)
- prior to age of 40
what happens in turners syndrome?
XO
- normal oocyte growth requires both X -> oocyte death
- normal ovary development requires normal germ cells –> ovarian dysgenesis
how can we preserve eggs during chemotherapy?
• Freezing embryos – need partner ~25% (IVF)
• Freezing eggs – less successful ~10% –> male partner not needed
• Time delay, ovarian stimulation ->few months –> cant take a lot of hormones
Freezing ovarian tissue – experimental - since 2004
what happens to a female at an increasing age?
- FSH and LH rise
- AMH declines
- antral follicle count decreases
- ovarian reserve decreases
what are some central causes of endocrine disorders?
- hypothalamic / pituitary
- gonadotrophin levels low or absent due to problems wit hypoT or PG
- low FSH/LH
- low estrogen levels too
what is hyperprolocatinaemia?
- XS PLN secretion from lactotrophs of APG
- suppresses release of FSH/LH
- prolactin secreting tumours of these cells
- tumours affecting PG stalk suppressing DA release (inhibits usually)
- DA antagonists used to treat schizophrenia
what is PCOS?
- polycystic ovaries on ultrasound (multiple follicle development)
-
what are the symptoms of PCOS?
- oligomenorrhoea
- amenorrhea
- hirsutism
- obesity
- infertility
what is dysmenorrhea and what are the two different forms?
- painful menstruation
- primary –> higher levels of endometrialPG / uterine hypercontractility
- secondary –> endometriosis ( extra-ovarian endometrial growth)
what are the presenting symptoms of male disorders?
- loss of libido
- infertility
- reduced testicular volume
- gynecomastia
- loss of body hair
- decreased muscle mass
how can we diagnose male disorders?
- lower T levels
- look at FSH/ LH levels to see if the problem resides in testis or brain
what are the primary causes of male disorders?
- testicular insensitivity / damage
- loss of T levels from gonads
- high FSH/ LH due to absence of feedback from T
–> low levels of FSH/LH are indicative of damage to HPG axis (brain)
what is Klinefelter syndrome?
- 47 XXY
- 2/3rds of chromosomal abnormalities attending for infertility
–> azoospermia observed
pea-sized testes –> due to low T but high FSH/LH levels
what are the central causes of male disorders ?
- gonadotrophin secretion is low or absent due to problems with HPG
- low FSH/ LH
what are the associated risks with testosterone replacement ?
- prostate cancer
- atrophy of testes azoospermia
- polycythaemia
- CVS hypertrophy
- arrhythmias
- 3ml testes
treatment of male hypogonadism ?
- weight loss ( estrogen)
- aromatase inhibitors
- block estrogen receptor
- give HCg -> LH and HCG share the same receptor
- adipocytes –> estrogen -> weight loss prevents this
- exogenous Testosterone –> correct levels ensured or too much can become inhibitory
how are endocrine disorders classified?
- hypothalamic / PG disease (secondary or central)
- gonadal damage -> peripheral/ primary)
- PCOS –> common