Pathophysiology: Testicular Disorders Flashcards
19 year old male with failure to enter puberty and anosmia (cant smell anything)
Kollman’s syndrome: no migration of nerves? Treatment: GnRH
65 year old male with fatigue and erectile dysfunction with viral illness within 2 years. Testes normal size and firm.
Mumps orchitis! Tx: give T
43 year old male with erectile dysfunction and headaches, mastodynia, bitemporal field defects, gynecomastia, normal testes but soft.
Prolactinoma. (vision defect) low FSH LH, high prolactin. Tx: MRI and Dopaminergics: Cabergoline, bromocriptine, T
54 year old male with impaired memory while on testoterone therapy
SHBG
What oes GnRH signal?
FSH from anterior pit
LH from anterior pit
What does FSH do?
+ sertoli cells sperm production (testes)
What does LH do?
+ leydig cells testosterone (testes)
What does follistatin do?
Inhibits neighboring teste activins and inhibins
What do activins do?
Sertoli cells make them, and they stimulate FSH beta subunit production
What do inhibins do?
Seminiferous tubules and Sertoli cells make them, they suppress FSH secretion in the anterior pit.
What does injucry to seminiferous tuble lead to chemically?
Elevated FSH, since inhbins are gone.
Hypothalamic disorders look like what in testes/
Low GnRH–>low LH and FSH
Pituitary disorders lead to what in the tests?
Low GnRH, low LH/FSH, low T, no spermatogenesis
Gonadal disorders mean what?
Failure of testosterone production from leydig cells or spermatogenesis, no feedback leads to elevated LH and FSH
Post gonadal disorders are caused by what?
No testosterone recepotr function
Testicular failure labs?
FSH: High
LH: High
T: low
Germinal aplasia labs?
FSH: high
LH: normal
T: normal
Hypogonadotropic hypogonadism labs?
FSH: normal-low
LH: normal-low
T: Low
Anabolic hormone labs?
Body builder +
FSH: 0
LH: 0
What are testicular hypothalamic diseases?
*No puberty:
Kallman’s syndrome
Prader willi
Lawrence moon
Kallman’s syndrome presentation?
Anosmia
Prader Willi presentation?
Hyperphagia Obesity Hypotonia Micropenis Small hands Small feet
Lawrence moon syndrome presentation?
Retinitis pigmentosa
Polydactyly
Pituitary diseases?
Fertile eunich syndrome: LH def.
Isolated FSH def.
Hyper prolactinemia: inhibit GnRH and libido
Hemochromatosis: loss of LH and FSH
Marijuana effect on prolactin?
Decrease Dopa, increase prolactin
Testicular disorders have high what?
Low T
HIGH FSH and LH due to absent feedback of T
What are chromosomal disorders of testes?
Klinefelters XXY: tall, breasts, euchanoid, mar fan
XYY- no sperm
Noonan’s syndrome (XO)-looks like turner’s
XX Male syndrome-normal height, no MR, azospermia
What determines body shape in lack of androgens?
Prepubertal or Postpubertal
What does pre puberty gonadal failure look like?
A child
What does post puberty gonadal failure look like?
Decrease muscle mass Loss of libido Impotence No sperm Hot flashes Poor concentration
When is testosterone usually highest?
Morning
What is T bound to in blood?
Sex hormone binding globulin (SHBG)
What percent of T is free?
2%
What is the increase in SHBG in aging?
1% per year… this causes decline in free T
What is the most accurate T test?
Equilibrium dialysis of free T
What can cause low SHBG?
Hypothyroidism
Acromegaly
Obesity
Is the half life of LH or FSH longer?
FSH is longer
What does tonic release of FSH and LH cause? How is FSH and LH usually released?
Tonic= hypogonadism (like leupron) Pulsatile= normal
What is the only tonic hormone released?
Prolactin
What shuts off prolatin release?
Dopamine
What does prolactin do to FSH and LH?
Decrease FSH and LH
What does prolactin do to libido?
Decrease libido independent of T levels
If you have a prolactin increase, think what iatrogenic?
DRUGS! OTC or illicit or prescription
High prolactin does what?
Prevents fertility! Stress causes low dopa,increasing prolactin, cutting off libido and saving the herd from infants at a stressfull time.
