male hypogonadism and infertility Flashcards
what stimulates the hypothalamus to release GnRH
kisspeptin
what is the male HPG axis
hypothalamus releases GnRH –> ant pit releases LH and FSH –> gonads release testosterone –> testosterone causes hypothalamus to reduce GnRH
what cells produce testosterone and what hormone causes them to do this
leydig cells from LH
what is testosterone bound to
SHBG and albumin
what is testosterone converted into
dihydrotestosterone (highly active) and oestradiol
what is primary hypogonadism
problem lies within sex organs eg testes
what biochem is seen in primary hypogonadism
high LH and FSH and low testosterone (hypergonadotrophic hypogonadism)
what can cause male primary hypogonadism (6)
klinefelter’s syndrome, undescended testes, chemo/ radio, mumps, medications haemochromatosis
what is klinefelter’s syndrome and how do you diagnose it
genetic 47 XXY - karyotyping
what are symptoms of klinefelter’s syndrome
infertile male, small testes, learning disabilities, breast development, female pubic pattern
what is secondary hypogonadism
problems lie outwith testes eg in hypothalamus/ pituitary
what biochem is seen in secondary hypogonadism
low LH, FSH and testosterone
what can cause secondary hypogonadism in males
Kallmann’s syndrome, tumours, HIV AIDS, brain damage
what is kallmann’s syndrome
isolated GnRH deficiency, no sense of smell, colour blind, cleft lip
what are male hypogonadism symptoms
small sex organs, decreased body hair, higher voice, tall, slim, long arms, decreased bone and muscle mass
