Veterinary Internal Medicine Nursing

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22 | The top 4 things you need to know about prostatic disease as a vet nurse

Laura Jones

Prostatic disease is a common cause of stranguria, haematuria and even recurrent UTIs, especially in older male dogs and entire males.

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And the truth is, we can use many nursing skills to diagnose and treat prostatic disease. 

Today, we’ll take a look at the four types of prostatic disease we see, the signs they cause, and the diagnostics, treatment, and nursing considerations for these patients.

But first, it’s time for a little anatomy refresher…

The prostate is a bilobed organ that completely encircles the proximal urethra and the neck of the urinary bladder in male dogs.

The prostate functions as an accessory sex organ, producing fluid that nourishes, protects, and prolongs the survival of sperm as it is released during reproduction.

There are four common prostatic disorders seen in dogs: benign prostatic hyperplasia (BPH), prostatitis, prostatic neoplasia, and prostatic cysts.

Let’s start with BPH

Benign prostatic hyperplasia is the most common prostatic disease in older, entire male dogs. It can begin as early as 2.5 years old; by age 5, around 80% of male dogs will have the disease.

In BPH, the prostatic gland slowly grows over the patient’s lifetime due to the influence of testosterone and other androgens or due to an altered androgen-to-oestrogen ratio.

The constant hormonal influences can lead to not just the growth of the prostate but also the formation of cysts and fluid within the gland. Cystic hyperplasia tends to develop from the age of about 4.

What signs do we see in these patients?

Clinical signs may be absent, especially in earlier stages of the disease, where the prostate has not enlarged significantly. However, as the gland grows, so does the impact on the urethra - since it passes through the gland.

Commonly reported signs in BPH patients include persistent or intermittent haematuria, haemospermia, and haemorrhagic discharge from the prepuce.

On physical examination, an enlarged prostate gland can be palpated via a rectal exam. Unlike other prostatic diseases, prostatic enlargement should be symmetrical, and the prostate should not be painful on palpation.

And how do we diagnose the disease?

Prostatomegaly (prostatic enlargement) can be confirmed on imaging - x-rays will show an enlarged prostate gland, and ultrasound should show diffuse, symmetrical prostatic enlargement with multiple cysts.

Once we’ve imaged our patient, we’ll need to collect prostatic samples for analysis. There are a few ways of doing this - such as an FNA of the prostate or a prostatic wash. The latter is a skill nurses and technicians can perform quite easily - if you can place a urinary catheter, you can do a prostatic wash!

Here’s how to do it…

  1. Place a urinary catheter as you normally would, and empty the bladder 

  2. Flush the bladder with sterile saline, keeping the last 10ml in a plain pot as a pre-massage sample

  3. Slowly withdraw the catheter to the level of the prostate - this can be performed under ultrasound guidance to ensure you’re in the correct location

  4. Using one hand, massage the prostate rectally whilst simultaneously infusing 20-30ml of saline via the urinary catheter, past the prostate and into the bladder

  5. Aspirate the saline gently, collecting your prostatic wash sample for analysis.

In BPH, a prostatic FNA (if possible) is the preferred sampling method. But keep that prostatic wash in mind because we’ll need it for some of our other diseases…

And how do we treat BPH?

Castration is the treatment of choice wherever possible. After castration, the prostate will shrink within a few weeks, returning to its normal size over several months.

For dogs used for breeding, medical therapy is used. Options include finasteride and Ypozane, aka osaterone acetate.

Finasteride is a drug commonly used for the treatment of male pattern baldness in people and works by blocking the conversion of testosterone to DHT - that hormone which stimulates the prostate gland.

Ypozane is a licensed therapy for dogs in Europe. It’s a drug that is chemically related to progesterone and works by blocking the transport of testosterone into the prostate gland.

Let’s talk about prostatitis.

Prostatitis, aka prostatic infection, is the second most common prostatic disease we see and can be acute or chronic.

Acute prostatitis

Acute prostatitis is rare and usually haematogenous in nature (aka originating from the bloodstream).

Patients are typically severely affected, presenting with pyrexia, caudal abdominal pain, dehydration and even septicaemia and septic shock in severe cases.

When examining the acute prostatitis patient, an enlarged, painful, irregular prostate may be palpated. Depending on how systemically unwell the patient is, you may also see changes to their hydration and perfusion parameters and their temperature. Look out for:

  • Tachycardia (compensated shock, pain)

  • Bradycardia (decompensated shock)

  • Pale or bright red MMs (shock, sepsis)

  • Tacky or dry MMs (dehydration)

  • Prolonged or rapid CRT (shock, sepsis)

  • Increased skin tent (dehydration)

  • Sunken eyes (dehydration)

  • Hypotension (shock)

And if these are seen, they need to be managed accordingly - either with fluid boluses to correct any hypovolaemia and restore circulating volume, (+/- vasopressors in septic shock to increase vascular resistance and maintain BP), or longer-term fluid therapy rates for dehydrated patients.

Chronic prostatitis

Chronic prostatitis, on the other hand, is usually associated with BPH and ascending infection from the urethra. Since prostatic fluid commonly refluxes into the urinary bladder, concurrent urinary tract infections are common in chronic prostatitis cases. The prostate can also act as a reservoir for infection, meaning that UTIs can recur even after successful treatment with courses of appropriate antibiotics.

Patients with chronic prostatitis may show no clinical signs except recurrent UTIs and signs associated with lower urinary tract infections - such as haematuria, pollakiuria, stranguria and concentrated, malodourous urine.

On physical examination, these patients typically show evidence of BPH on rectal palpation, though rarely, the prostate can be normal in both size and shape.

How do we diagnose prostatitis patients?

We’ll likely run some bloodwork on these patients, including biochemistry and haematology. Haematology typically reveals infection-related changes, including neutrophilia with a left shift, a monocytosis, and toxic WBCs on a smear exam.

Then, it’s time to think about imaging and sampling. Ultrasonography is our preferred imaging method, and this typically shows hypoechoic areas with pockets of fluid, with or without changes to the urinary tract associated with chronic or recurrent UTIs (in chronic prostatitis cases).

A urine sample should be collected and submitted for full analysis and culture. Ideally, we’d obtain this via cystocentesis; if you’re taking it via urinary catheter, be very careful about aseptic preparation and handling of the catheter, as we know contamination can still occur in these samples.

Following urine sample collection, a prostatic wash is performed and submitted for cytology and culture, as we want to look for infection in the bladder and prostate gland.

One quick thing to note, though - massaging the prostate in a patient with acute prostatitis can, theoretically, release bacteria into the blood and cause septicaemia. That being said, we still perform prostatic washes in our acute prostatitis patients, and we need to weigh up the risks of this complication with the benefits of achieving a diagnosis in our patients.

So you’ve got your diagnosis, and now it’s time to talk treatment.

Treatment for prostatitis depends on whether it’s acute or chronic and how severely affected the patient is. 

Acute prostatitis patients often require stabilisation with intravenous fluid therapy and analgesia to manage their pain, alongside appropriate antibiotics for the prostatic infection.

When selecting an antibiotic, it’s vital to use one that crosses the blood-prostate barrier and enters the prostatic tissue; non-ionised, fat-soluble antibiotics are typically used. Long courses >4 weeks generally are required.

In some cases, patients may have such a severe prostatic infection that a prostatic abscess develops, requiring surgical management.

Patients with chronic prostatitis usually require treatment for BPH alongside management of their infection. 

Moving on to prostatic and paraprostatic cysts…

Occasionally, large cysts are found within or adjacent to the prostate gland.

The former is known as parenchymal prostatic cysts and truly occurs within the prostate. In contrast, the latter are known as paraprostatic cysts and are closely associated with the prostate gland but not communicating with it.

Prostatic cysts are more likely to become infected or abscessed, as we discussed when talking about prostatitis; small, uninfected cysts may resolve with castration.

Paraprostatic cysts usually form on top and alongside the prostate or at the back of the prostate within the pelvic cavity. These cysts are remnants of the Mullerian ducts, which are embryological remnants of the female reproductive system normally found in males. As the cysts grow, they can displace the urinary bladder and impinge on the rectum, causing stranguria, dysuria and constipation.

So how do we diagnose and treat them?

Diagnosis is made on imaging, with the cysts appearing as smooth, anechoic, fluid-filled structures within or next to the prostate gland.

They’re treated surgically, with partial or complete resection, and then omentalisation to prevent refilling. Prostatic or periprostatic surgery is not without risk. Complications associated with the procedure include:

  • Iatrogenic urethral trauma

  • Temporary or permanent urinary incontinence

  • Urinary retention

  • Recurrence of cyst growth.

Medical management is not effective in these cases, and castration alone is unlikely to help - it is preferable to remove the cyst(s) first (if possible) and then castrate the patient.

What about prostatic neoplasia?

Prostatic neoplasia is relatively uncommon and has no breed preference. We don’t know exactly why it happens, though we know there is a link between hormonal imbalances during ageing and prostatic tumour formation.

Interestingly, castration does not protect dogs from developing prostatic neoplasia in the future, and the incidence of prostatic neoplasia is higher in castrated dogs.

The most common cancer of the prostate is carcinoma, originating from ductal or urothelial tissue. Urothelial (transitional cell) carcinoma from the urethra can also invade the prostate gland.

Metastasis is common in the sublumbar lymph nodes, lumbar vertebrae, pelvic bones, and lungs.

What signs do we see in these patients?

Clinical signs include dysuria, stranguria, pollakiuria, and voiding with a narrow stream of urine. Urinary obstruction and a complete inability to pass urine may also be seen.

Faecal tenesmus and constipation may also be noted, and faeces passed may be narrower or flatter in shape.

Physical examination usually reveals an uneven prostatic surface with enlargement of one or both prostatic lobes and small, firm protrusions or nodules may be apparent. In some cases, changes such as additional tissue growth on the pelvic bones may also be felt via rectal examination.

How do we diagnose the disease?

Like our other prostatic diseases, we’ll need to image the prostate. With neoplasia, we’ll also want to take survey imaging of the chest and abdomen to stage the patient and look for local and distant metastasis. Generally, we prefer to do this via a thoracic and abdominal CT scan, followed by guided sampling of the prostate itself.

A prostatic biopsy is required for diagnosis; FNAs of surrounding abnormal areas or potential sites of metastasis are also taken.

So we’ve got our diagnosis - time to talk treatment!

Sadly, there is currently no effective curative treatment for prostatic carcinoma in dogs. Because most patients have metastases at the time of diagnosis, and prostatic removal comes with a high risk of urinary incontinence, surgical management is not recommended.

Radiation therapy for prostatic neoplasia is reported but comes with a risk of incontinence as the radiation can cause fibrosis of the bladder.

Typically, we treat these patients medically with cyclooxygenase inhibitors (NSAIDs) such as piroxicam, meloxicam, or carprofen. These have been shown to significantly increase survival times in dogs with prostatic carcinoma.

What about nursing patients with prostatic disease?

We have a wide and varied role in supporting patients with prostatic disease. The exact nursing skills we’ll use depend on the type of prostatic disease they have and include:

  • Triage, stabilisation, fluid balance assessment and sepsis monitoring in the acute prostatitis patient

  • Prostatic wash and sample collection in patients with acute and chronic prostatitis

  • Postoperative care in patients following prostatic surgery, such as patients with prostatic or periprostatic cysts - so thinking about analgesia, fluid balance, nutrition, wound care and monitoring urination, for example,

  • Urinary monitoring in all prostatic disease patients - looking for ongoing stranguria, haematuria, dysuria and noting whether urinary obstruction is present

  • Faecal monitoring - since we know constipation can frequently be seen in patience where the enlarged prostate gland is pushing on the rectum, causing a mechanical obstruction

  • Urinary catheter placement, care and management

  • Long-term cancer care and QOL monitoring & support in patients with prostatic neoplasia

So there you have it! My top considerations for managing patients with problematic prostates - from BPH to acute prostatitis, to prostatic carcinoma and beyond, there are a lot of nursing skills we can use to support these patients. So, if you’re not performing prostatic washes in practice, or you’re not involved in the long-term support of your prostatic carcinoma patients, what are you waiting for? Have a chat with your vets and see what you can do to help give your patients even better care!

Did you enjoy this episode? If so, I’d love to hear what you thought - screenshot it and tag me on Instagram (@vetinternalmedicinenursing) so I can give you a shout-out and share it with a colleague who’d find it helpful!

Thanks for learning with me this week, and I’ll see you next time!

References and Further Reading