For one, pet owners may not realize their pet is at risk. In fact, in some cases, this insult may even be subclinical—we know acute kidney injury can occur in otherwise "healthy" pets. Additionally, if it's been diagnosed, pet owners may feel overwhelmed and unsure of what it means in the short and long term for their pet. Despite these obstacles, pet owners deserve to understand more. Injury can originate from a variety of causes and, left undiagnosed, may result in lasting permanent impairment of kidney function. These practical communication tips and areas of focus can help veterinary teams build trust and create informed pet owners.

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Why Testing and Early Detection Is So Critical

Until recently, small animal veterinarians weren't able to diagnose kidney injury until it was farther advanced. For pet owners, this can be associated with increased treatment costs, a poorer prognosis and quality of life, and emotional strain due to chronic care management.

Communicate with clients that instead of having to be reactive, we can now recommend and provide a more proactive strategy to screen for kidney injury. Early detection through testing with the novel kidney biomarker cystatin B allows veterinarians to intervene much earlier.^24,42-44 This gives us the opportunity to slow or stop damage to the renal tubular cells, improving prognosis and limiting permanent disease changes.

Common Causes for Kidney Injury

One of the first questions pet owners want to know when we suggest a possible concern around kidney injury is what could have caused this injury in their pet. It's a valid question we can answer, but first, preface that there are three main categories of kidney injury with many possible etiologies.⁴²

• Prerenal: We can explain this as conditions in their pet's body that affect how much blood flows to the kidney. The less blood flow or more compromise, the more stress and damage the kidney receives. These can include periods of dehydration, anesthetic episodes, blood loss, congestive heart failure (CHF), gastric dilatation and volvulus (GDV), and other systemic conditions.
• Renal injuries: These affect the kidneys themselves. There are various causes here, but we can discuss them in two main categories: infectious and noninfectious. Many infectious agents can cause kidney injury, and the more common ones include leptospirosis, ehrlichiosis, and Lyme disease. Noninfectious causes include toxin exposure, trauma, damage from medications that stress kidneys, like nonsteroidal anti-inflammatories, and even cancer.
• Postrenal causes: These stem from obstruction of the urinary flow downstream from the kidney such as urethral plugs, urolithiasis, urethral stricture, or neoplasia.

Signs of Kidney Injury in Pets

Another common question pet owners ask when learning about new diseases or conditions is what they should look for in their pet at home. While we can answer them with general signs to watch for, conveying two important facts is critical. One, acute kidney injury progresses through four distinct phases, and clinical signs typically don't occur until the third phase of maintenance.⁴² By this time, the glomerular filtration rate (GFR) has decreased, the kidney has been exposed to compromised blood flow and oxygen, and inflammation has settled in, destroying renal cells. It's only at this point that we start to see clinical signs like lethargy, vomiting, diarrhea, and anorexia. Some of these cases may have polyuria, oliguria, or even anuria, and less commonly, seizure activity. Ultimately, these signs are not specific for acute kidney injury in dogs and warrant, at minimum, a physical exam.

The second related fact is that physical examination findings can also be nonspecific. While we might identify dehydration, bradycardia, scleral injection, or, less commonly, enlarged, painful kidneys, these abnormalities do not always point directly to acute kidney injury. It's important to commend the pet owner for seeking veterinary care and reinforce how specific diagnostic testing paired with history and physical exam results can help identify kidney injury much earlier.

Treatment for Diagnosed Kidney Injury

If kidney injury is detected on a cystatin B test, we can provide supportive care and other tailored treatment promptly, often before there is functional change. It's important to communicate to pet owners that specific treatment depends on the underlying cause and may create a resolution or become more of a long-term managed care plan. The other part of treatment to prepare pet owners for is patient monitoring. Recommend traditional function tests to assess response to treatment both acutely and for chronic management.

Common Questions Pet Owners Might Have About Kidney Injury

There are a few other common questions pet owners may have regarding kidney injury in pet:

• Will my pet need prescription food indefinitely?
• What will monitoring and treatment cost?
• What is the prognosis for my pet—will they live an expected lifespan?
• Is this contagious to my other pets?
• Could I have prevented this in my pet?

The answers to these questions will depend on the individual case, blood work results, primary cause (if identified), and response to recommended therapy. For mild acute kidney injury caught early enough to intervene and resolve the primary reason, prognosis may be more favorable, and treatment costs will be more limited. For more severe kidney injuries where the damage creates more irreversible change, the prognosis will be poorer, treatment and monitoring costs, including prescription renal diet, may escalate, and their pet may have a reduced lifespan. Encourage pet owners to continue asking questions to make informed decisions and understand common causes that could be prevented, and be prepared to answer their questions with understanding that this could be overwhelming and new for them.

References: https://www.thevetiverse.com/en/latest/sdma-references/