Kidney Enlargement in Cats
Written By hannah hollinger
Published: 10/19/2016Updated: 11/19/2021
Veterinary reviewed by Dr. Linda Simon, MVB MRCVS
Kidney Enlargement in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Kidney Enlargement?
Kidney enlargement is a condition in which one or both kidneys experience inflammation, fluid retention, swelling, or an abnormal growth. These situations can cause the kidneys to grow in size. This inflammation may be caused by a variety of conditions, some of which are life-threatening. Enlargement can be a warning sign of acute or chronic kidney failure. The kidneys are necessary to filter waste and toxins from the blood stream, so any condition that impairs their function will quickly have a negative impact on other bodily functions. Certain breeds are more prone to developing kidney issues, including Siamese, Persian, Burmese, and Maine Coon. Any cat experiencing symptoms of kidney enlargement or kidney failure should be seen by a veterinary professional.
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Kidney Enlargement Average Cost
From 492 quotes ranging from $200 - $5,000
Average Cost
$800
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Symptoms of Kidney Enlargement in Cats
Kidney enlargement can cause a variety of symptoms, although it is possible for the kidneys to be enlarged and the cat to be asymptomatic. If the kidney is very enlarged, it may be possible to feel or see the swollen area. The symptoms associated with an enlarged kidney closely resemble symptoms of several serious medical conditions. Any cat experiencing symptoms like these should be seen by a medical professional immediately. 
Symptoms include:
  • Lethargy 
  • Weakness
  • Depression or apathy
  • Lack of appetite
  • Diarrhea
  • Constipation
  • Vomiting
  • Weight loss
  • Dehydration
  • Increased urination
  • Discolored urine
  • Blood in vomit, urine, or feces
  • Increased thirst
  • Pale gums or mucous membranes
  • Abdominal bloating, swelling, or mass
  • Swelling around the area of one or both kidneys
  • Bad breath
  • Abdominal pain and sensitivity to touch
  • High blood pressure
  • Anemia
  • Seizures
Causes of Kidney Enlargement in Cats
Kidney enlargement can be a symptom of a variety of medical conditions. The kidneys may become inflamed as a result of injury, infection, or serious conditions like cancers or poisoning. Enlargement may also be related to issues with other organs or portions of the renal system. Some of the common causes of kidney enlargement in cats and other companion animals include:
  • Bacterial infection
  • Parasite Infestation
  • Feline leukemia virus
  • Urinary tract infection
  • Urinary tract obstruction
  • Blood clots
  • Poor blood flow through the kidneys
  • Cysts
  • Polycystic kidney disease
  • Certain cancers, including leukemia and lymphoma
  • Toxins, including heavy metals, lilies, solvents, and antifreeze
  • Some cancer treatments
  • Certain medications
  • Envenomation
  • Heart disease
  • Immune system diseases
  • Severe dehydration
  • Kidney stones
  • Amyloidosis
  • Trauma or injury
Diagnosis of Kidney Enlargement in Cats
Diagnosing kidney enlargement can be challenging because its symptoms are similar to other conditions and because kidney enlargement can be a symptom of a variety of medical issues. This will require your veterinarian to use multiple diagnostic techniques to verify kidney enlargement and determine its underlying cause. Be prepared to provide your veterinarian with information about your pet’s medical history, any recent medical issues or procedures, any symptoms you have observed, and how long your cat has been presenting symptoms. A full physical examination may be performed. It is often possible for veterinary professionals to diagnose enlargement during a physical examination because the kidney swelling or abdominal mass is palpable. 
Additional diagnostic methods will likely be used to determine what is causing kidney inflammation in your cat. A blood panel, including complete blood count and a close look at urea, creatinine and phosphorous levels, is common. Urinalysis with particular attention to protein and blood in the urine is another routine method for identifying the underlying cause of kidney issues. Urine and blood cultures will help determine if an infection is responsible for your cat’s condition. Additionally, urine or feces may be examined under a microscope for signs of parasitic infection, crystals etc. X-rays and other imaging techniques including an ultrasound scan will provide additional detail on the kidneys and interrelated systems. In some cases, exploratory surgery or tissue biopsy may also be used to form a diagnosis. 
Treatment of Kidney Enlargement in Cats
If your cat is experiencing kidney or renal failure, treatment will be required immediately. Kidney failure can quickly become life-threatening. Hospitalization may be required for several days or weeks to stabilize and treat your pet. Medication may be prescribed to treat the underlying cause of kidney enlargement, but medications carry some risk as the kidneys will be responsible for processing any medication. Some common treatments associated with kidney enlargement in cats include:
Dialysis
The purpose of dialysis is to filter the blood, which is a normal function of the kidneys. When the kidneys are functioning poorly, waste material is not properly filtered. Dialysis can help with filtering. There is a moderate risk associated with dialysis, but the treatment will be recommended if the benefits outweigh the risk. This treatment is not widely available and can be incredibly costly.
Surgical Intervention
Surgery may be needed to clear an obstruction, remove a tumor, or repair certain issues. Surgery carries some risk and the patient will require careful observation during surgery and recovery. Your pet will be hospitalized post-surgery to ensure there are no complications. 
Intravenous (IV) Fluids 
Fluid therapy can assist with dehydration, removing some impurities from the system, and balancing electrolyte levels. This common treatment carries a very low risk but is generally provided on an inpatient basis. 
Feeding Therapy 
Proper nutrition and caloric intake is essential to your pet’s treatment and recovery. If your pet is experiencing weight loss or anorexia, a feeding tube or appetite stimulant may be used. 
Kidney Transplant 
A kidney transplant may be recommended if your cat’s kidney is damaged beyond repair. Only certain cats will be a good candidate for transplant. Factors including your cat’s age, overall health, and the availability of a kidney that is a good match will all be considered. As with any surgical procedure, there is a moderate risk associated with this treatment. This surgery is not available in every country.
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Recovery of Kidney Enlargement in Cats
Your pet’s recovery from kidney enlargement will depend largely on the cause of the enlargement. In some cases, your cat’s condition will be easily treated, and recovery will occur fairly quickly. This is the case for the majority of infections and many toxins. Certain conditions that can cause kidney inflammation are not so easily treated. Additionally, if significant damage has occurred to one or both kidneys, the prognosis may be poor. 
If your cat is healthy enough to return to their home, fresh water should be kept nearby at all times. Proper fluid intake is essential to maintaining proper kidney function. Your veterinarian may also recommend dietary changes. Be sure to follow your veterinarian’s instructions for medications and follow-up visits as required. 
Kidney Enlargement Average Cost
From 492 quotes ranging from $200 - $5,000
Average Cost
$800
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Kidney Enlargement Questions and Advice from Veterinary Professionals
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Crossed
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Simba
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17 Months
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My pet has the following symptoms:
Lethargic, Anorexic, Doesn'T Drink
My cat wasnt eating well since a few days and was nearly not drinking at all, i wasnt worried about his drinking as he was provided with wet food and milk so that sums up the water intake. But when my cat left eating and whenever he tried to eat he would go out of control and try to throw up like its stuck or something and sometimes would loose his bladder control too. I took him to the vet and he diagnosed that my cat was constipated and that both his kidneys were swollen. He wrote me a diet plan for my cat and emphasised on water intake. He gave my cat enema for his constipation and a syrup to follow with his food. After few days my cat has started eating on his own but he still has that throwing up thing, it looks so painful and he looses his mind when he's in that state, its like he can't breath or something. Please help me with his condition. Thank you.
July 23, 2018
0 Recommendations
You should continue with the treatment prescribed by your Veterinarian and try to get Simba drinking, it is very important for his water intake to be increased; the vomiting may be attributable to a few different causes but getting the water intake increased is the first step here even if you need to mix wet food with a little water to get water into him. If there is no improvement you should return to your Veterinarian. Regards Dr Callum Turner DVM
July 23, 2018
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domestic short hair
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Meme
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4 Months
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My pet has the following symptoms:
None
Enlarged Kidney
My mother's 4 months old kitten has chronic large kidneys (she has always head them). The vet did an ultrasound and noted that they were an unusual color (completely dark with no spots). My mother is seeing a specialist but could not great a straight answer from the vet about what this could mean. Besides from enlarged kidneys, the kitten experiences no symptoms. She eats, drinks a usual amount of fluid, urinates normally. I was curious if I could be provided with some answers as to what this might be.
July 20, 2018
0 Recommendations
If the internal part of the kidneys are dark it would indicate that there is little to no kidney tissue inside the kidneys (grey or white indicates tissue black is air or fluid) which would be attributable to a condition like polycystic kidney disease, hydronephrosis among others; without examining Meme and reviewing the medical file I cannot say what the specific cause is. Regards Dr Callum Turner DVM
July 21, 2018
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American Shorthair
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Willy
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12 Years
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My pet has the following symptoms:
Kidney Inflammation, Aneorexia
Willy my 12 year old male orange tabby has went from 20 to 10.5lbs over the last year and a half. Two vet visits have yielded solutions that haven’t helped. He is emaciated and won’t eat but constantly begs for food. He occasionally throws up in large volumes overnight and drinks/urinates more frequently that last two months. He was treated with anti nausea meds, and 2 rounds of antibiotics. At this point he’s fed whichever high protein food I can get him to accept (last week included: cooked chicken, fresh raw pork, raw ground beef, tuna (with water), and Science Diet K/D perscription cans. All the meat was mixed with cat vitamins and pro-flora. He’ll rarely eat the same type of food twice a day. I can email you his complete labs and x-ray (as PDF if won’t paste correctly) In short: fecal was clear, X-rays showed inflamed kidneys (redily palpable), BUN 69mg/dL high, creatinine 2.9mg/dL high, White BC 21.1 10^3L high, RBC 5.7 10^6 low, HGB 9.1 g/dL low. Monocytes 5% high, Absolute Neutrophils 10550 high, Absolute Monocytes 1055 high, Absolute Eosinophils 2532 high. All other blood, urine, and fecal test parameters were within normal range. Thanks in advance for your generous help in saving my little buddy 💗 Related to: https://wagwalking.com/cat/condition/kidney-inflammation
July 13, 2018
0 Recommendations
In a case like Willy’s, if your Veterinarian hasn’t narrowed in on a cause and treatment it would be wise to consult with a board certified Specialist; since you have the blood reports and x-rays I would recommend that you contact PetRays for a board certified Internal Medicine Specialist to give you another opinion. Regards Dr Callum Turner DVM http://petrays.com/specialists/internal-medicine/
July 13, 2018
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Persian
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Candy
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9 Years
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My pet has the following symptoms:
Lethargy, Fever, Enlarged Kidney
Hi, my cat had a kidney infection 2 months ago since she got dehydrated. Took her to the vet got an X-ray done she had an enlarged left kidney. However the renal function came normal with the urea and creatinine in normal limits. Recently she has been lethargic and has been feeling feverish so we took her to the vet again and got another xray done. This time the x ray showed multiple masses on her left kidney. We are still waiting for the blood work to come back to check her Renal functions but she has been slightly active (as compared to before) and has been eating normally. She has no problems urinating however a few times she did urinate outside the box. She isn’t feeling thirsty though. I know the most probable diagnosis is a renal lymphoma but is there a chance it could be anything else?
June 30, 2018
Answered by Dr. Michele K. DVM
0 Recommendations
Lymphoma is high on the list, and an ultrasound may be a good idea to further evaluate the kidney and see whether surgery might be the best option for her to see if it is not lymphoma. Without pathology, it is very difficult to say what the growths might be. I hope that she is okay!
June 30, 2018
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Persian
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ipin
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7 Years
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My pet has the following symptoms:
Kidney Enlargement
A few months ago, I found blood in my cat's piss so I brought him to vet. He then got diagnosed with enlarged kidney. Ultrasound and blood test also done to him and everything seems normal. He normally only eats Royal Canin's Urinary Treatment food, but since then I added Renal Special but not given as much in amount. His appetite has always been good, and I've always made sure that he has enough water and actually drink it. However, I haven't noticed his kidneys being any smaller, yet. Since his appetite and weight are always healthy (no problems, about 9-10pounds), should I worry? I also add wet food to balance his diet.
June 30, 2018
0 Recommendations
There are various causes of kidney enlargement requiring medical and dietary management as well as treatment of the specific underlying cause; depending on the cause of the kidney enlargement the treatment will differ, but the ultimate goal is to reduce the stress on the kidneys to prevent any further enlargement or kidney damage. If there is not a worsening of symptoms, I would keep an eye on Ipin for the time being and visit your Veterinarian for regular checkups. Regards Dr Callum Turner DVM
June 30, 2018
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Burmese
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Mekia
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4 Months
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My pet has the following symptoms:
Diarrhea
Anemic
White Blood Cells In Urine
Bloated Stomach
Drinking More
Possible Fluid In Stomach
Mekia went in to the vets yesterday for her round in vaccination and the vets discovered enlarged kidneys 2 fingers big. She is only 980 grams while her brother is 1.80kg. We have only had the two for 4 weeks. Mekia was only 500gms then. She is eating well, active, toileting well and seems happy enough. The vet did blood tests and an ultrasound. I can't really remember exactly what she said as I was in shock. But she said it could be a kidney infection or a genetic disease. If it's the genetic disease she most likely won't make it past 1 year old. We have started her on antibiotics and have to go back in week. Then she may need to be sedated for a more thorough ultrasound. We are shattered.
Kidney Enlargement Average Cost
From 492 quotes ranging from $200 - $5,000
Average Cost
$800
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