What causes hyperphosphatemia in dogs?

Hyperphosphatemia is a health condition that can occur in dogs when they have too much phosphorous in their blood, which causes an imbalance or disturbance in the body’s natural electrolyte balance. The condition can prove fatal if left untreated, but rather than being an illness or issue in and of itself, it is actually indicative of something else being wrong, with hyperphosphatemia appearing as a secondary complication of the original underlying disorder.

If your vet suspects that your dog has hyperphosphatemia or if your dog has recently been diagnosed with the condition, this will naturally be very concerning for you, and can be quite confusing too.

In this article we will explain what hyperphosphatemia is, how it occurs, how it affects individual dogs, and what can be done about it. Read on to learn more about the causes of hyperphosphatemia in dogs.

More about hyperphosphatemia

Hyperphosphatemia is quite a complex condition to understand, because it involves a range of different functions relating to the blood, bones, chemical balance and hormone levels of the dog’s body.

Hyperphosphatemia occurs when there’s too much phosphorous circulating within the dog’s blood, and this important trace element helps to ensure the normal function of the muscles and nerves when it is present in the right quantities. Phosphorous is stored within the dog’s bones, and the phosphorous levels within the bloodstream of the healthy dog are controlled and regulated by the parathyroid hormone, which is in turn an important part of healthy kidney function.

However, if your dog has a kidney disorder or hormone imbalance, their ability to regulate the level of phosphorous in the blood will be compromised, leading to elevated levels that can cause serious problems for your dog’s general health.

Hyperphosphatemia is usually symptomatic of a kidney or hormone problem, and is correctly referred to as a symptom rather than a condition in and of itself.

What causes hyperphosphatemia in dogs?

Hyperphosphatemia is most common within young dogs under a year old, and senior and elderly dogs over the age of about seven. In terms of the cause of the condition (or rather, the underlying original condition that in turn leads to hyperphosphatemia itself), this tends to vary depending on the age of the dog in question, as follows:

When hyperphosphatemia develops in young dogs, this is usually related to a lower than normal level of renal absorption of phosphorus, and an increased level of intestinal absorption in its turn.

In senior and elderly dogs, hyperphosphatemia is often linked to thyroid hormone imbalances and/or the onset of renal failure. It can also be a symptom or secondary complication of the onset of diabetes.

However, this is only a general guide, and will not apply to every dog with the condition, regardless of their age. Hyperphosphatemia in dogs can also develop as a result of a wide range of other issues, including serious and prolonged worm infestations, injuries, severe dehydration (particularly long term) and poisoning or toxicity, particularly if caused by raisins or grapes.

What are the symptoms of hyperphosphatemia in dogs?

Hyperphosphatemia causes elevated levels of phosphorous in the blood, and this is considered to be a secondary complication of another condition. This means that the full range of symptoms your dog displays – as well as their severity – can be quite variable and won’t always be easy to spot.

Some of the most common indicators of hyperphosphatemia in dogs include:

• Extreme thirst and associated excessive need to urinate.
• Muscle tremors or fits of the shakes.
• Signs of poisoning or toxicity, if the condition is fast in onset.
• Renal or kidney problems.
• Excessive weight gain or loss if the condition occurs due to a hormone imbalance.

The rather obtuse nature of the symptoms and the fact that they often begin very subtly, worsening and becoming more acute over time, can make it very hard to spot the onset of hyperphosphatemia at home. If you have any concerns, book your dog in for a consult with your vet and ask them to investigate.

If your vet suspects hyperphosphatemia, they will run some tests to check the phosphorous levels in your dog’s blood, and to try to establish the underlying condition or root cause of the problem.

Can hyperphosphatemia in dogs be treated or managed?

How your vet goes about treating hyperphosphatemia in your dog will depend on what is causing the condition in the first place, and identifying and treating it, or bringing it under control.

Because so many different health conditions and imbalances can result in hyperphosphatemia, any given dog’s treatment plan will need to be uniquely designed for them, and if their underlying health condition can be controlled effectively (such as a new diagnosis of diabetes when properly managed and medicated) then their hyperphosphatemia too should resolve itself, returning the body’s phosphorous levels to their healthy norms.

Left untreated, hyperphosphatemia can be fatal – and so it is important to begin investigation as soon as possible to identify the root cause of the condition and tackle it, in order to restore your dog to good health.