113.Prostate

Question 1

T/Fthe prostate is the sole accessory sex organ of male dogs

Answer 1

TRUEprostate encircles the urethra in dogs (only partly in cats)bilobedfibromuscular capsule

Question 2

prostatic size and position

Answer 2

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

Question 3

blood supply of prostate

Answer 3

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

Question 4

vascular zones of the prostate

Answer 4

1. capsular2. parenchymal3. urethral

Question 5

time of first secretory function of the prostate

Answer 5

4 monthsperiodic acid schiff positive stain for secretory function evidentsecretion increases with agesecretion is androgen mediatedprostatic secretion is considered the THIRD fraction of ejaculate

Question 6

constituents of prostatic fluid

Answer 6

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

Question 7

function of prostate in testosterone regulation

Answer 7

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

Question 8

diagnostic testing approach to prostatic disease

Answer 8

1. 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)

Question 9

asymmetry of prostate gland of digital rectal may give what differentiasl

Answer 9

1. abscess2. cysts3. neoplastic disease4. granulomatous disease

Question 10

prostatic changes seen on abdominal radiographs

Answer 10

size, shape, positiondisplacement of colon or bladderemphysematous changes (prostatitis)mineralization (castrated–neoplasia)+/- retrograde contrast to determine communication with bladder/urethracompression of colorectal areaLN enlargement

Question 11

prostatic changes seen on ab US

Answer 11

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

Question 12

benign prostatic hyperplasia

Answer 12

glandular (young) and complex (older) formspresence of prostatomegaly is not necessarily indicative of dzpain free, homogenous, symmetricaldyschezia**confirm with cytologysurgical tx: CASTRATION

Question 13

medical treatment of BPH

Answer 13

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

Question 14

most common route of infection to prostate

Answer 14

ascending from urethraE.coli, Staph, Strep, Proteus, KlebsiellaMycotic infections can also be seen (ascending or hematogenous)

Question 15

normal defense mechanisms of urogenital tract

Answer 15

–exfoliating urethral cells (shed uropathogens)–mucus secretions (trap uropathogens)–intermittent wash out with urine–local production of cytokines, Ig, and defensins–mobilization of WBC

Question 16

signs of prostatitis

Answer 16

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

Question 17

T/Fprostatic infections in castrated dogs have been shown to resolve considerably more rapidly than those in intact dogs

Answer 17

TRUEcastration promotes involution of hyper plastic and cystic changesrecommend castration!

Question 18

Antibiotic selection for the prostate

Answer 18

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

Question 19

surgical techniques for mgmt of prostatic abscess or cysts

Answer 19

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

Question 20

cysts within the parenchyma vs separate from prostate

Answer 20

paraprostatic—develop separately from prostateprostate—develop within capsule of the gland

Question 21

T/Funlike many other prostatic diseases, urinary incontinence and dysuria are frequently seen in dogs with large prostatic cysts

Answer 21

true

Question 22

most common neoplasia of the prostate

Answer 22

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

Question 23

T/FCOX-2 is NOT usually expressed in normal prostatic tissue but has been detected in 75% of prostatic carcinoma cells

Answer 23

TRUE

Question 24

cause of prostatic metaplasia

Answer 24

circulating estrogen concentrations are abnormally increased through the presence of estrogen secreting tumorsfeminization (bilateral alopecia, pendulous prepuce/penile hypoplasia, lactation, gynecomastia)

Question 25

surgical approach to prostate

Answer 25

caudal midline laparotomy +/- pubic symphysiotomyneurovascular structures found on dorsal aspect of prostate

Question 26

complications of draining techniques for prostatic abscess/cysts

Answer 26

1. 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

Question 27

what is the sole indication for total prostatectomy

Answer 27

neoplasiapoor prognosis and procedure has a lack of impact on systemic diseaseR:A (end to end anastomosis of urethra with U cath in