Kidney Inflammation in Cats

The kidneys are a very important organ in cats for regulating multiple key systems in the body. They help to regulate blood pressure and production of hormones and enzymes, maintain a balance of electrolytes, and remove waste from the bloodstream. 

Most kidney inflammation develops because of an undetected bladder or urinary tract infection, which then travels up the ureter to the kidneys where it results in inflammation, damage, and severe pain. When the kidneys are inflamed, they usually become abnormally enlarged. Many cats make a full recovery after receiving a lengthy protocol of antibiotics and fluid treatment.

Cats are highly prone to kidney disease and related inflammation. Although it affects all ages and breeds of cats, older cats and Persian or Himalayan cats are more likely than other cats to develop a kidney condition. Most affected cats experience either pyelonephritis (infection of the kidney), acute kidney disease (AKD), or chronic kidney disease (CKD). As with many diseases in cats, it can be difficult to diagnose the exact cause of kidney inflammation.

Unfortunately, there are no early warning signs of kidney inflammation, which is what makes diagnosis challenging. Sometimes there are no signs until the cat is experiencing actual kidney failure. Common symptoms include:

• Dehydration
• Increased thirst
• Discolored urine 
• Increased urination
• Diarrhea
• Vomiting
• Decreased appetite
• Fever
• Lethargy
• Weight loss
• Foul-smelling breath
• One or both kidneys are palpably larger than normal
• Abdominal mass
• Abdominal pain
• Malaise
• Muscle weakness
• Depression

There are several potential causes of kidney inflammation:

Pyelonephritis

Pyelonephritis, or infection of the kidney, is usually due to an underlying bacterial infection of the urinary tract. Pyelonephritis often gives rise to acute kidney disease (AKD) and chronic kidney disease (CKD). 

Kidney Disease

Acute kidney disease is often caused by ingestion of toxins such as harmful plants, antifreeze, pesticides, cleaning products or ibuprofen, but is also caused by pyelonephritis. The kidney becomes severely injured and enlarged. The exact cause of progressive, chronic kidney disease is unknown, however,it can be triggered by dental disease and urinary tract infection. 

Other Causes

Other common causes are stones in the kidney or urinary tract, malformation of the kidneys at birth, immune-mediated disease, high blood pressure, and chronic bacterial infection of the kidneys.

A preliminary diagnosis is made by taking a complete blood profile and a urinalysis. The cat will receive a palpation exam and X-rays to assist the veterinarian in finding kidney stones and assessing the shape and size of the kidneys. 

A blood panel will shed light on the buildup of compounds in the blood, while the urinalysis will provide your vet with helpful information about the extent of the damage to the kidneys. If the kidneys are enlarged, most vets will also request an ultrasound, a urine culture, or a kidney tissue biopsy.

Most cats will be treated on an outpatient basis unless the cat is in crisis due to dehydration or renal failure. If your cat needs to be hospitalized, it will be given fluids, minerals and electrolytes intravenously to correct imbalances in the blood. If the causes of the kidney inflammation is a urinary tract blockage, the obstructions must be removed immediately. 

Treatment of kidney inflammation is long-term. Most cats receive a high dosage of antibiotics for four to six weeks. In some cases, intravenous fluids will be administered. In rare cases only, surgery to remove the inflamed kidney will be recommended. 

Dietary changes are also very helpful. Most cats respond well to a therapeutic diet of high-quality protein and supplements of vitamins B, D, and omega-3 fatty acids. All dietary protocols address the negative consequences of the disease affecting the kidneys, and help with weight gain, reducing acid build-up, reduction of nitrogen waste buildup, and maintenance of healthy B-vitamin and potassium levels. 

Depending on the amount of damage and injury that occurred to the kidney due to inflammation, cats may be able to recover full kidney function. All of the treatment protocols will help to keep your cat comfortable and in stable condition. 

In most cases, cats benefit tremendously from treatment and can live a long and healthy life. Your cat will go to the veterinarian for regular checkups, every three to six months, to be evaluated and monitored. A physical exam will be performed during each visit, and if necessary, a blood and urine test performed to provide more detailed information about the state of your cat's kidneys. 

At home, make sure your cat has 24 hour access to fresh, clean, chlorine and fluoride-free water. Keep an eye on the amount of food and water your cat consumes each day so that you can easily notice any sudden changes in weight and hydration.