113.Prostate Flashcards
T/Fthe prostate is the sole accessory sex organ of male dogs
TRUEprostate encircles the urethra in dogs (only partly in cats)bilobedfibromuscular capsule
prostatic size and position
size is androgen driveninvolution occurs after castrationabdominal until 2 months of age where it sits in the pelvisat puberty, enlarges and sits partially in abdomencan migrate further cranially with hyper plastic enlargementhalf the gland abdominal by 4 years of agedorsal–rectumlateral–levator ani musclesventral–pubic symphysis and ab wall
blood supply of prostate
prostatic arteries (branch from internal pudendal artery)branch to supply ductus deferens, caudal vesicular artery, and caudal rectalprostatic arteries divide cranial, middle, caudal before perforating capsule and becoming sub capsular arteries supplying glandular tissue
vascular zones of the prostate
- capsular2. parenchymal3. urethral
time of first secretory function of the prostate
4 monthsperiodic acid schiff positive stain for secretory function evidentsecretion increases with agesecretion is androgen mediatedprostatic secretion is considered the THIRD fraction of ejaculate
constituents of prostatic fluid
considerably more acidic than men (6.1-6.5) which is supposed to be more alkaline than female repro tract–hi Zn (antibacT?)–hi proteins (acid phosphatase, canine prostate specific esterase)–electrolytes hi K, Cl similar Na to plasma
function of prostate in testosterone regulation
circulating T is metabolized by 5alpha reductasetestosterone—–>5alpha dihydrotestosterone5 HT binds receptors to control prostatic growthas prostate size increases, tissue 5HT decreases BUT tissue androgen receptors increase and the prostate becomes more responsive to androgens as it ages
diagnostic testing approach to prostatic disease
- Hx and PE (ortho and neuro)2. digital rectal exam3. MDB, UA, Brucella titer4. ejaculate, prostatic transurethral wash, FNA—culture, cytology5. ab rads +/- postive/negative retrograde cystourethrograms6. ab US** 7. Biopsy—core biopsy, incisional(8. Advanced imaging (CT/MRI)9. scintigraphy)
asymmetry of prostate gland of digital rectal may give what differentiasl
- abscess2. cysts3. neoplastic disease4. granulomatous disease
prostatic changes seen on abdominal radiographs
size, shape, positiondisplacement of colon or bladderemphysematous changes (prostatitis)mineralization (castrated–neoplasia)+/- retrograde contrast to determine communication with bladder/urethracompression of colorectal areaLN enlargement
prostatic changes seen on ab US
size, position, margination, symmetry, echo density, cavitation, homogeneity +/- needle aspirate or core biopsy (prostate, LN)+/- therapeutic drainage of cysts/abscess potentially with replacement of fluid with Ab or alcohol
benign prostatic hyperplasia
glandular (young) and complex (older) formspresence of prostatomegaly is not necessarily indicative of dzpain free, homogenous, symmetricaldyschezia**confirm with cytologysurgical tx: CASTRATION
medical treatment of BPH
sx tx: CASTRATION #1medical tx: goal to decr T production or decr conversion to 5alpha HT–antiandrogens–LH inhibitors–LH releasing hormone inhibitors–5 alpha reductase inhibitor
most common route of infection to prostate
ascending from urethraE.coli, Staph, Strep, Proteus, KlebsiellaMycotic infections can also be seen (ascending or hematogenous)
normal defense mechanisms of urogenital tract
–exfoliating urethral cells (shed uropathogens)–mucus secretions (trap uropathogens)–intermittent wash out with urine–local production of cytokines, Ig, and defensins–mobilization of WBC
signs of prostatitis
systemic illnesspurulent or sanguineous penile dischargepain on defecation, urination, or palpationprostatomegaly–asymmetric, “doughy”stiff hindlimb gaithighly characteristic multiloculated appearance of capsular tissue surrounding material with a flocculent fluid signal
T/Fprostatic infections in castrated dogs have been shown to resolve considerably more rapidly than those in intact dogs
TRUEcastration promotes involution of hyper plastic and cystic changesrecommend castration!
Antibiotic selection for the prostate
based on sensitivity of organisms culturedhighly lipid soluble Ab preferred (though some argue that inflm breaks blood lipid prostate barrier)KNOWN TO DIFFUSE WELL INTO PROSTATEMETCmarbofloxacinenrofloxacinTMSchloramphenicol
surgical techniques for mgmt of prostatic abscess or cysts
resection of cyst/abscess (break down cavitations to allow for communication!) use urethral catheterhistopathy and culture samples takenirrigation/lavage stoma drainage–marsupialization (infrequently done)passive drainage (penrose)active drainage (closed suction drain)capsulectomy and omentalization***partial prostectomyother medical options: Ab 4 weeks, US drainage +/- alcohol ablation
cysts within the parenchyma vs separate from prostate
paraprostatic—develop separately from prostateprostate—develop within capsule of the gland
T/Funlike many other prostatic diseases, urinary incontinence and dysuria are frequently seen in dogs with large prostatic cysts
true
most common neoplasia of the prostate
adenocarcinoma (more common in castrated dogs)aggressive disease with rapid mets (80%) to regional LN, lungs, bones (20%)prognosis is guardedpalliation with tube cystostomy or urethral stent, COX 2 inhibitor
T/FCOX-2 is NOT usually expressed in normal prostatic tissue but has been detected in 75% of prostatic carcinoma cells
TRUE
cause of prostatic metaplasia
circulating estrogen concentrations are abnormally increased through the presence of estrogen secreting tumorsfeminization (bilateral alopecia, pendulous prepuce/penile hypoplasia, lactation, gynecomastia)
surgical approach to prostate
caudal midline laparotomy +/- pubic symphysiotomyneurovascular structures found on dorsal aspect of prostate
complications of draining techniques for prostatic abscess/cysts
- prolonged drainage2. recurrence of abscess/cysts (premature closure of stoma, failure to drain all cavities, inadequate omental packing)3. drain obstruction4. early removal of drain5. urethrocutaneous fistula (with use of drains)6. urinary incontinence
what is the sole indication for total prostatectomy
neoplasiapoor prognosis and procedure has a lack of impact on systemic diseaseR:A (end to end anastomosis of urethra with U cath in
