Ch314 - Prostatic diseases Flashcards
What percentage of prostatic diseases are subclinical?
75% of prostate diseases are subclinical.
Which breeds are predisposed to BPH?
Large breed dogs, including:
- Doberman Pinscher
- German Shepherd Dog
- Rhodesian Ridgeback
- Labrador Retriever
What is the frequency (in order of most common to least common) of prostatic disorders in dogs?
- BPH: 45%
- Acute or chronic prostatitis: 38.6%
- Abscesses: 7.7%
- Cysts: 5%
- Neoplasia: 2.6%
- Squamous metaplasia: 0.2%
How common is prostatic disease in cats?
Prostatic diseases are exceedingly rare in intact or neutered cats
What are the three main factors that contribute to BPH development?
- Older age
- Functioning testes
- Dihydrotestosterone (DHT) that concentrates in hyperplastic prostatic tissue
hat are the common clinical signs of BPH?
- Blood dripping from prepuce
- Hematospermia (1st and 3rd fraction of semen)
- Hematuria
- Tenesmus with thin tape-shaped feces
- Constipation
- Dyschezia
- Less commonly: dysuria or urinary incontinence
- Subfertility
How quickly does the prostate decrease in volume after castration for BPH?
The prostatic volume begins decreasing within 7-14 days after castration.
What are the two types of BPH and their characteristics?
- Glandular BPH:
* characterized by thickened epithelium with developed “alveoli” especially in the periurethral area. - Complex BPH:
* characteristics of the glandular form plus areas of atrophic epithelium and, eventually, cyst formation
What are the medical treatment options for BPH in breeding dogs and what are their actions?
- Finasteride (5-alpha-reductase inhibitor):
* 1. Prevents conversion of testosterone to DHT
* 1. Doesn’t reduce libido or sperm production - Osaterone acetate (progestogen/antiandrogen)
* Reduces prostate volume
* Minimal effect on fertility - Deslorelin acetate (GnRH analog):
* Subcutaneous implant
* Reduces prostate volume >50% after ~6 weeks
Deslorelin acetate (GnRH analog) reduces prostatic volume by how much and for how long?
Reduces prostate volume >50% after ~6 weeks
Effect lasts up to 48 weeks with 4.7 mg implants
What are the most common bacterial organisms found in septic prostatitis?
Aerobic organisms are most common, including:
* Escherichia coli
* Staphylococcus sp.
* Streptococcus sp.
* Proteus sp.
* Pseudomonas spp.
* Brucella canis
* Klebsiella sp.
What are the characteristics of antibiotics that best penetrate the prostate?
- High lipid solubility
- Low protein binding
- High pKa (like trimethoprim, clindamycin, chloramphenicol)
- Zwitterion characteristics (fluoroquinolones)
How long should antibiotics be given for prostatitis?
Acute prostatitis: 4-6 weeks
Chronic prostatitis or prostatic abscess: 6-8 weeks
What are the key differences between acute and chronic prostatitis symptoms?
Acute Prostatitis:
* Fever, anorexia, lethargy
* Vomiting, caudal abdominal pain
* Difficulty rising, painful stiff gait
* Low sperm quality
* Hematospermia, pyospermia
* Possible peritonitis/septic shock
Chronic Prostatitis:
* Often subclinical
* Recurrent urinary tract infections
* Low sperm quality
* Mild lethargy
* Urethral discharge
* Hypo/infertility
When should prostatic cultures be repeated during antibiotic treatment for prostatitis?
- 7-10 days after starting antibiotics
- 30 days after antibiotics are discontinued
What are the two main types of prostatic cysts?
- Retention cysts
- Paraprostatic cysts (PPCs)
How are retention cysts classified by size?
- Large: ≥3 cm in greatest diameter
- Medium: >1 to <3 cm
- Small: ≤1 cm
- Micro: ≤1 mm
What are the key characteristics of paraprostatic cysts?
- Usually associated with remnants of uterus masculinus
- Typically single structures around the prostate
- Attached to prostate capsule
- Large cysts can invade abdominal or pelvic cavity
- May be asymptomatic or show signs similar to BPH
What are the treatment options for prostatic cysts?
Surgical options:
* Surgical excision or debridement
* Omentalization
* Marsupialization
* Penrose drain positioning
Medical options:
* Castration (alone for small cysts)
* Medical treatment to reduce prostatic size
* Combination therapy recommended for large cysts
What constitutes a definitive diagnosis of prostatic infection based on culture?
Growth of >10,000 bacteria/mL
A 2-log difference between prostatic and urine colony-forming unit counts suggests bacterial prostatitis
What are the typical ultrasound findings in prostatic neoplasia?
- Focal to diffuse hyperechoic areas
- Areas of hemorrhage or necrosis
- Mineralization
- Asymmetry
- Irregular capsule outline
- Loss of normal contour
- May show sublumbar lymphadenopathy and visceral metastases
What are the typical examination findings in BPH on digital rectal examination?
- Large prostate
- Symmetrical
- Mobile
- Normally firm
- Not painful
- May have asymmetrical/irregular surface with soft “fluctuant” areas if cysts present
What are the typical laboratory findings in acute prostatitis?
- Neutrophilic leukocytosis with left shift
- Increased alkaline phosphatase activity
- Hematuria
- Bacteriuria
What are the ultrasound characteristics of BPH?
- Prostatomegaly
- Uniformly echogenic parenchyma
- May have nodular areas (usually isoechoic or slightly different from surrounding parenchyma)
- May show increased prostatic perfusion
- May have cysts with well-defined margins
What three questions should guide the decision to treat BPH?
- Is the BPH life-threatening?
- Is the BPH adversely affecting the function of other organs?
- Is the BPH adversely affecting the dog’s quality of life?
How should prostatic abscess treatment be approached?
- Supportive care: Intravenous fluids, Analgesics
- Appropriate antibiotics based on culture/sensitivity
- Drainage options: Surgical (omentalization preferred), US-guided percutaneous drainage with ethanol injection
- Consider castration 5-7 days after starting antibiotics
What are the recommended monitoring intervals for untreated mild BPH?
Every 3 to 6 months for dogs with:
* Mild signs
* Signs that don’t affect quality of life
What is the prevalence of BPH in intact male dogs by age?
- ~80% of intact male dogs >5 years of age
- 95% of intact male dogs >9 years
- Can occur as early as 2 years of age
- Most dogs don’t develop clinical signs
What is CPSE and its significance in BPH?
CPSE = Canine Prostatic Specific Esterase
* Concentrations progressively increase over time in dogs with BPH
* Levels typically >90 ng/mL when prostates are estimated to be >2.5 times normal size
* Cannot differentiate between BPH, bacterial prostatitis, or prostatic carcinoma
What conditions can predispose to prostatic infection?
Conditions that reduce normal defense mechanisms or alter prostatic architecture:
* BPH
* Cysts
* Squamous metaplasia
* Neoplasia
What complications can occur with prostatic abscesses?
- Tenesmus from colonic compression
- Dysuria from urethral compression
- Peritonitis
- Septic shock
What radiographic changes might be seen with prostatic neoplasia?
- Prostatomegaly
- Prostatic mineralization
- Regional lymphadenopathy
- Evidence of metastasis: Lungs, Skeleton (especially ventral aspects of lumbar vertebrae)
What are the most common prostatic neoplasias in dogs?
adenocarcinomas and undifferentiated carcinomas
What is the common survival time for dogs with prostatic neoplasia
weeks to months
What treatment options are there for prostatic neoplasia?
- Total and subtotal prostatectomy (if no metastases)
- Treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) alone
- or in combination with chemotherapy
What factors affect survival time in prostatic neoplasia?
Presence of metastasis (80% metastasized at diagnosis)
How does castration affect prostatitis treatment?
- May decrease need for long-term antibiotic use
- Recommended 5-7 days after starting antibiotics
