2.11 Male small animal repro diseases

When do penile spines in cats disappear?

Within 6 weeks castration

3 most common testicular neoplasia types and potential hormones produced

• Sertoli cell tumour

  • Oestrogen → feminisation

• Seminoma

  • (rarely oestrogen → feminisation)

• Leydig (interstitial) cell tumour

  • Testosterone

Why should cryptorchid testicles be castrated?

More susceptible to torsion and malignant neoplasia

3 haematological changes of feminisation

Oestrogen depresses the bone marrow:

• Anaemia

• Leukopenia

• Thrombocytopenia

Testicular neoplasia gives the testes an enlarged size. How is this differentiated from infection/abscess/orchitis/torsion and torsion?

• Infection etc → pain

• Scrotal hernia → undefined mass

4 signs of orchitis or epididymitis

• Epididymal enlargement (+ small/firm testicle if chronic)

• Pain or oedema

• Abscessation via scrotum → purulent material

• Septic peritonitis (due to rupture) → systemic malaise

3 origins of orchitis/epididymitis

• Most common - urinary tract (UTI)

• Direct penetration (e.g. bite)

• Haematogenous spread (unlikely)

How does a doppler ultrasound help diagnose testicular torsion?

No blood flow seen on doppler in torsion

Causes of paraphimosis (4)

Nonerect penis protrudes from prepuce and cannot be retracted/retained normally

• Narrow preputial orifice

• Penile enlargement - prevents retraction

• Abnormally short prepuce

  • E.g. preputial tissue contracts caudally following trauma

• Weak preputial or retractor penis muscles

Medical treatments for paraphimosis (5)

• Replacement

• Lubrication

• Hyperosmolar solutions - reduce penile size

• Heat or cold - reduce penile size

• Urethral catheter

Surgical treatments for paraphimosis (4)

• Enlargement of preputial opening

• Phallopexy

  • fix penis to preputial mucosa

• Preputial lengthening or reconstruction

  • Often in conjunction with phallopexy

• Partial penile amputation (complicated)

How do you surgically treat phimosis in dogs and cats? (2)

Full thickness V shaped incision and suture away from anus → widen preputial opening

• Dogs - dorsal preputial surface

• Cats - ventral preputial surface

Priapism definition

Persistent erection of >4 hours not associated with sexual excitement

4 potential associations with priapism

• Trauma

• Perineal abscess

• Neurological disease

• Neoplasia

2 categories of priapism (in humans)

• Non ischaemic - not painful

  • Entire penis partially rigid

• Ischaemic (emergency) - penile pain and necrosis

  • Painful rigid shaft

  • Soft glans

Surgical treatment of ischaemic priapism in dogs and cats

Penile amputation + urethrostomy:

• Dog - scrotal urethrostomy

• Cat - perineal urethrostomy

6 types of penile soft tissue tumours

• Transmissible venereal tumour (TVT)

• Squamous cell carcinoma (SCC)

• Papilloma

• Lymphoma

• Mast cell tumour (MCT)

• Adenocarcinoma

3 types of os penis tumours

• Osteosarcoma

• Ossifying fibroma

• Chondrosarcoma

Which 2 types of penile tumours can be treated without any penile amputation?

Transmissible venereal tumour and lymphoma

• Chemo + medical treatment

How do you treat most penile tumours?

Partial penis amputation or complete amputation + scrotal urethrostomy

• Except TVT + lymphoma

Penile injury 3 presenting signs

• Haemorrhage (most common)

• Dysuria

• Urine extravasation

Hypospadias

Failure of urogenital fold fusion (on ventral penis) → incomplete penile urethra

Why is it important to find the origin of preputial discharge?

• Prepuce - more localised

• External urethral orifice - can be either urinary or repro origin

4 prostatic diseases in a dog

• Benign prostatic hypertrophy (BPH) - most common

• Prostatitis or abscessation

• Prostatic cysts

• Neoplasia

What demographic is benign prostatic hypertrophy typically associated with?

Older entire male dogs - testosterone dependent disease

• Normal aging change may contribute to clinical disease

3 signs of BPH

Uniform prostatic enlargement

• Dyschezia

• Occasional dysuria

• Sometimes haematuria or urethral bleeding

3 medical treatments for BPH

• Antiandrogens (reduce testosterone)

• Deslorelin (unlicenced)

  • implant lasts 6 months in dogs V 1-4 years in ferrets

• Faecal softeners (dyschezia)

• (Oestrogens - but not recommended due to risk of squamous metaplasia)

Distinguishing prostatomegaly BPH and prostatitis (± abscessation)

• BPH - firm prostate

• Prostatitis - softer prostate due to abscess capsule

  • Rupture can lead to septic peritonitis

How is persistent frenulum treated in dogs?

Sectioning under GA

• penis and prepuce should separate after puberty

3 characteristics of prostate ultrasound during prostatitis

• Appears multiloculated (multiple chambers)

• Flocculant (cloudy), anechoic (black) fluid

• Large hyperechoic capsule

3 types of prostatic abscess drainage

• Omentalisation

  • Flush fluid and bring omentum in cavity for blood supply and further drainage

• Closed system drainage

  • Ultrasound guided, manually put drain in

• Marsupialisation

  • Obsolete, create hole through skin for drainage

2 goals of prostatitis treatment

• Antibiosis

• Removal of secretory function → glandular reduction

Why is partial prostatectomy rarely done to treat prostatitis? (2)

• Complicated surgery

• Only works for focal lesion away from urethra (otherwise risk of urethral harm)

Most common fluid in (para)prostatic cysts

Urine 20% of the time

Other names for prostatic and paraprostatic cysts

• Prostatic = parenchymal

• Paraprostatic = periprostatic

What do you always do when surgically treating a (para)prostatic cyst?

Biopsy cyst wall - check for malignancy

2 most common types of prostatic neoplasia

• Prostatic adenocarcinoma

• Prostatic/urethral transitional cell carcinoma

Which demographic of animal is prostatic neoplasia more common in?

Castrated animals

Most common metastasis site for prostatic neoplasia

Very aggressive - tend to metastasise and invade locally

• Spinal metastasis → therefore bone formation

• (different from spondylosis - more irregular in metastases)

Why is prostatectomy rarely done in prostatic neoplasia?

Very aggressive, tends to metastasise - very poor prognosis