Prostate Enlargement

The prostate gland is one of the male reproductive glands that sits at the base of the penis, wrapping around the urethra as it leaves the bladder. It produces some of the fluid components of semen, and it can become problematic in male dogs if it becomes larger than normal. This is because the enlarged gland pushes down on the urethra, making it difficult and uncomfortable to urinate, and it can also press up onto the colon, making it difficult for the dog to pass faeces as well.

In entire male dogs, the influence of male sex hormones (such as testosterone) can lead to a gradual enlargement of the prostate gland over time. This is known as benign prostatic hypertrophy (BPH). This is a process of hypertrophy which means that the enlargement is caused by the prostate tissue getting bigger and thicker, rather than being the result of the uncontrolled production of new cells, which is what occurs in types of neoplasia (cancer).

However, there are other conditions such as prostatic abscesses, prostatic inflammation (prostatitis) and prostatic cysts which can all cause similar signs to BPH and may even be present at the same time. There is also a form of prostatic cancer that can occur in dogs, and will cause the same signs because of the prostate gland's increased size, but it is not common in dogs.

BPH with or without accompanying prostatitis, cysts or abscessation, is the most common cause of prostatic enlargement. Owing to its root cause being the long-term exposure to testosterone, it's adult, uncastrated male dogs that are at risk of the disease, particularly older dogs.

Dogs with BPH often struggle to pass urine comfortably, so they tend to strain or spend longer than usual trying to have a wee. They may try and wee multiple times and only pass short, interrupted streams, and they might grunt or moan. These dogs will often have bloody or dark urine, and these signs can all make owners think their dogs has a urinary tract infection.

Some dogs will also struggle similarly to pass faeces, appearing to be constipated, passing only small hard or misshapen nuggets of poo, and maybe showing discomfort on defecating too. In some cases, the enlargement of the prostate gland can be so great as to make it uncomfortable for the dog to walk, giving him an abnormal gait in the hindlegs which might make it seem like a lameness or neurological problem.

It's generally fairly straightforward to diagnose BPH, your vet will suspect this based on the dog being uncastrated and having compatible signs. Most of the time, an enlarged prostate can be felt through the rectum when the vet has a feel at the dog's bottom, although this isn't always the case for very big dogs. Radiographs (X-rays) can help where we suspect a prostate problem, and the diagnosis can be confirmed using a combination of urine analysis and by examining the prostate with an ultrasound scan. The ultrasound examination will also alert the vet to the possibility of related problems like prostatitis, abscesses or cysts that might need some additional treatment. In some cases, we have to take a small sample of the prostate to see what type of tissue is involved.

Successful treatment of BPH is generally achieved by castration. Removing the testosterone influence allows the prostatic tissue to shrink back to a more normal size and removes the cause of discomfort. The dog may be prescribed some medication to help kickstart the process, until he's stable enough to have an operation and be castrated, and to ensure a positive response to castration should be achieved, but stable dogs can often be castrated immediately.

Whether or not the dog has accompanying infection or prostatic cysts is also important in deciding the treatment protocol. Abscessation and cysts will often require more invasive surgery because the diseased tissue needs to be drained and removed to help the problem resolve.

BPH tends to be more common in entire male dogs, and so it goes that castration can help to prevent this uncomfortable disease from occurring. However, the issue is a little more complex. In castrated male dogs, a prostatic problem can be more severe – prostate cancer seems to occur more frequently in castrated dogs than entire male dogs. BPH, on the other hand, is generally straightforward to treat and it isn't cancerous, but there is still the possibility for more serious disease such as when it's accompanied by abscessation or prostatic cysts.

There isn't really a right or wrong answer when it comes to castrating your dog, but it's always worth a thorough discussion with your vet about the risks and benefits to ensure that you make the right choice for your pet.