BPH Flashcards
What are the 4 zones of the prostate?
peripheral
central
transitional
anterior
What is the MC zone to develop prostate cancer?
peripheral zone
What is the MC zone to develop BPH?
transitional zone
What is the MC zone to develop prostatitis?
central zone
What are the 3 types of tissue in the prostate gland?
epithelial tissue
stromal tissue
capsule
What is the main function of the epithelial tissue?
What stimulates the epithelial tissue?
produce prostatic secretions
androgens
What is the primary receptor in the stromal tissue?
What stimulates the stromal tissue?
alpha 1 adrenergic receptors
(also seen in the capsule)
norepinephrine
(NE –> smooth muscle contraction –> extrinsic compression of the urethra –> dec bladder emptying)
What is the normal ratio of stromal to epithelial tissue?
2:1 (stromal:epithelial)
What is the ratio of stromal to epithelial tissue in BPH?
5:1 (stromal:epithelial)
Where is type 1 5alpha reductase located?
What does DHT cause in these locations?
sebaceous glands in the frontal scalp, liver, skin
causes acne, inc body/facial hair
Where is type 2 5alpha reductase located?
What does DHT cause in these locations?
prostate, genital tissue, hair follicles of scalp
induces growth and enlargement of the gland
In the pathogenesis of BPH, what do STATIC factors relate to?
enlargement of the prostate gland
depends on:
- androgens stimulating the epithelial tissue
- estrogens stimulating the stromal tissue
In the pathogenesis of BPH, what do DYNAMIC factors relate to?
excessive alpha adrenergic tone on the stromal tissue
results in contraction of the gland around the urethra
What are other factors implicated in the pathophysiology of BPH?
chronic prostatic inflammation
advanced atherosclerosis
dec release of nitric oxide
dec production of cGMP
What are other factors implicated in the pathophysiology of BPH?
chronic prostatic inflammation
advanced atherosclerosis
dec release of nitric oxide
dec production of cGMP
What are signs and symptoms of OBSTRUCTIVE vs IRRITATIVE BPH?
OBSTRUCTIVE:
- urinary hesitancy
- urine dribbling
- bladder fullness post voiding
IRRITATIVE:
- urinary frequency
- urinary urgency
- nocturia
What PSA level indicates an enlarged prostate?
1.4 ng/mL
How is mild asymptomatic/mildly bothersome BPH w/ no complications managed?
watchful waiting
behavior modification
12 month return visits
How is BPH w/ moderate or severe symptoms managed?
drug therapy or surgery
What are the 3 types of agents used in BPH drug therapy?
- agents that interfere w/ testosterone’s stimulatory effect on prostate gland enlargement
- agents that relax prostatic smooth muscle
- agents that relax bladder detrusor muscle
What are the non selective alpha 1 adrenergic antagonists?
Which factor do they target?
Doxazosin (immediate release)
Terazosin (immediate release)
Alfuzosin (extended release – less CV ADEs)
Prazosin
dynamic
What are the selective alpha 1 adrenergic antagonists?
Which factor do they target?
Tamsulosin
Silodosin
dynamic
Tadalafil
- MOA
- class
- which factor does it target?
causes smooth muscle relaxation (prostate, bladder neck, prostatic urethra)
PDE 5
dynamic
What precautions need to be considered with immediate release terazosin and doxazosin?
slow titration to minimize orthostatic hypotension and first dose syncope
solution: long acting formulation of doxazosin
Finasteride:
- MOA
- which factor does it target?
blocks 5alpha reductase enzyme
static
Bicalutamide, Flutamide:
- MOA
- which factor does it target?
blocks DHT at intracellular receptor
static
**not FDA approved for BPH – used for prostate cancer
Leuprolide, Goserelin:
- MOA
- which factor does it target?
blocks pituitary release of LH
static
**not FDA approved for BPH – used for prostate cancer
Megestrol Acetate:
- MOA
- which factor does it target?
blocks pituitary release of LH and blocks androgen receptor
static
**not FDA approved for BPH – used for prostate cancer
Oxybutynin, Mirabegron: MOA
relax detrusor muscle of bladder
What is the role of alpha1 adrenergic antagonist in BPH drug therapy?
interim measure
relieves voiding symptoms
At what size of the prostate are 5 alpha reductase inhibitors indicated?
What is their role in BPH drug therapy?
at least 40g
- delay symptom progression
- reduce complications
- dec gland size by ~25%
Among all alpha 1 adrenergic antagonists, what are their similarities and differences?
equally effective
differ in cardiovascular effects
What are the ADE’s associated with Terazosin and Doxazosin?
first dose syncope
orthostatic hypotension
dizziness
Which of the alpha 1 adrenergic antagonists is the gold standard? Why?
Tamsulosin
selectivity, less CV effects
**NOT more effective **
What is a major disadvantage of 5 alpha reductase inhibitors?
slow onset of action (takes up to 6 months to exert maximal effects)
5 Alpha Reductase Inhibitors: ADEs
GYNECOMASTIA
dec libido
erectile dysfunction
ejaculation disorders
Alpha Adrenergic Antagonists: ADEs
FLOPPY IRIS SYNDROME syncope lightheadedness orthostatic hypotension tachycardia nasal congestion ejaculatory dysfunction priapism
Alpha Adrenergic Antagonists: monitoring parameters
BP
HR
Alpha Adrenergic Antagonists: patient education
start at lowest dose - slow titration up
first dose at bedtime
caution w/ cataract surgery
seek medical attention if painful erection lasting longer than 4 hrs
5 Alpha Reductase Inhibitors: monitoring parameter
PSA (should dec by 50%)
Which agents relax prostatic smooth muscle?
alpha 1 adrenergic antagonists
phosphodiesterase inhibitors
Which agent decreases prostate size?
5 alpha reductase inhibitors
Which agent decreases PSA?
5 alpha reductase inhibitors
Which agent has NO cardiovascular effects?
5 alpha reductase inhibitors
Which agents exclusively treats irritative symptoms?
anticholinergic agents
mirabegron
(no efficacy in relieving bladder outlet obstruction)
Which agent has no sexual dysfunction ADEs?
phosphodiesterase inhibitors
Mirabegron: MOA
beta 3 adrenergic receptors inc production of cAMP –> relaxed detrusor muscle –> reduced irritative/voiding symptoms, inc bladder capacity, inc interval bt voidings
Mirabegron: monitoring parameters
BP
bowel habits
Mirabegron: class
beta 3 adrenergic agonist
Mirabegron: ADEs
dose related, reversible
HYPERTENSION IMPAIRED COGNITION tachycardia dry mouth nausea constipation diarrhea headache nasopharyngitis
What are the surgical options for BPH?
What are their indications?
TURP (biopsy possible) green light (no biopsy possible)
INDICATIONS:
- moderate-severe symptoms
- no response/don’t tolerate drug therapy
- BPH w/ complications
