Editing Evaluation and Management of Erectile Dysfunction (section)

=== Labs ===

* '''2018 AUA'''
** '''All men (2):'''
**# '''Fasting glucose or hemoglobin A1c''' (screen for occult diabetes)
**# '''Morning total testosterone'''
** '''Optional'''
*** '''Fasting lipids'''
*** '''Serum BUN/Cr'''
*** Other: optional testing such as thyroid-stimulating hormone (TSH), luteinizing hormone (LH) and follicle-stimulating hormone (FSH), prolactin, complete blood count (CBC), and urinalysis are added when dictated by clinical context.
* '''2021 CUA'''
** '''Fasting glucose or hemoglobin A1c in patients with either suspected vasculogenic or idiopathid ED'''
** '''Fasting lipids''' '''in patients with either suspected vasculogenic or idiopathid ED'''
** '''Morning total testosterone if (2):'''
**# '''Symptoms of testosterone deficiency'''
**# '''Failure of phosphodiesterase type-5 inhibitors'''
* '''Serum testosterone''' (Campbell's 11th edition)
** '''Typical range for total testosterone measurement is 250 to 1000 ng/dL'''
*** Because of individual variability, the normal range for which replacement therapy should be initiated remains unknown
** '''If the testosterone level is below or at the low limit of normal, blood draw should be repeated for confirmation'''; a mildly abnormal testosterone level might be found to be normal in 30% of patients on repeat testing. '''When proceeding with a second total testosterone determination, assessment of LH and prolactin should also be included.''' Measurement of serum gonadotropin will help to localize the source of the hypogonadism.
*** Elevated serum LH and FSH releases are appropriate pituitary responses to the low serum testosterone levels, which is consistent with testicular failure (primary hypogonadism).
*** Normal or low serum LH and FSH releases in the setting of low serum testosterone levels indicate an inappropriate response and suggest a central disorder (secondary hypogonadism).
*** '''Hyperprolactinemia''' '''causes hypogonadism by suppression of gonadotropin-release hormone from the hypothalamus''', '''which impairs the pulsatile LH secretion required for serum testosterone production by the gonads'''.
**** Suspicious of hyperprolactinemia is raised in the patient with low serum testosterone and low or inappropriately normal LH.
**** Identifying and addressing the underlying cause of hyperprolactinemia may improve ED
**** '''A prolactin-secreting adenoma should be treated radiologically and if necessary surgically. Bromocriptine, a dopamine agonist that lowers prolactin level and restores testosterone to normal, serves to reduce the size of the tumour.''' Neurological ablation becomes necessary if the therapeutic response to medication does not occur or visual effects are noted in association with optic-nerve compression.
**** Generally accepted guidelines provide indications for pituitary imaging: cases of severe central hypogonadism (testosterone <150 ng/dL) and suspicion of pituitary disease (i.e. panhypopituitarism, persistent hyperprolactinemia, or symptoms of tumor mass effect).