Bacterial Kidney Infection in Cats
Written By hannah hollinger
Published: 08/18/2016Updated: 11/16/2021
Veterinary reviewed by Michele K.
Bacterial Kidney Infection in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Bacterial Kidney Infection?
Infections of the urinary system in cats are most often the result of bacteria entering the body. Bacteria usually enter the cat’s body through the urethra and then travel to the bladder. In some cases, the bacteria causes infection in the bladder, known as Bacterial Cystitis. The infection can move on to the kidneys and cause infection there, known as pyelonephritis. Factors that increase the risk of a urinary infection include problems with urine flow, sugar in the urine, advanced age, overly dilute urine, a compromised immune system, or comorbidity of other diseases. As cats age, kidney concerns become more common.
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From 540 quotes ranging from $200 - $1,200
Average Cost
$400
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Symptoms of Bacterial Kidney Infection in Cats
In many cases, a cat does not exhibit symptoms until the infection is advanced. The greatest risk factor for kidney infection in your cat is that your cat will experience  kidney failure. A change in your cat’s urination habits may be a red flag for some type of kidney problem. If your cat seems to be spending too much time in the litter box or has urine accidents outside of the litter box, a urinary tract infection may be to blame. Symptoms to be aware of include: 
Causes of Bacterial Kidney Infection in Cats
Your veterinarian may not be able to pinpoint a specific cause of your cat’s kidney bacterial infection. In general, elderly cats and very young kittens are the most susceptible due to weakened or compromised immune systems. Other causes of pyelonephritis may include:
  • Stones in the kidney or ureter that prevent urine from flowing normally
  • Birth defects in young kittens, such as ectopic ureter (ureter bypasses the bladder and enters the urethra from outside the bladder wall)
  • Ureteral movement
  • A restriction in the blood supply to the kidneys 
  • An infection in the blood that spreads into the urinary tract/kidneys
  • Blockages in the urinary tract can cause sepsis (bacterial infection of the blood) or urosepsis (infection of blood from decomposed urine being forced into blood stream)
Diagnosis of Bacterial Kidney Infection in Cats
Pyelonephritis is hard to diagnose and difficult to treat. Your veterinarian will perform a complete physical examination and run a series of blood tests to diagnose the bacterial infection. The blood work will include a chemical profile and blood count as well as testing levels of potassium and phosphorus. Urine tests will also be run and will include urinalysis, bacterial culture testing and an electrolyte panel. In severe cases, contrast x-rays or ultrasound may be required. Other procedures in severe cases may include urine cultures obtained from the renal pelvis of your cat or a renal biopsy as a last resort. If your cat has kidney stones, an incision into the kidney may be needed to acquire some of the mineral content of the stone for analysis.
Be prepared to share with your veterinarian the symptoms you have observed and approximately how long that you have noticed the symptoms. Do not delay contacting your veterinarian as the bacterial infection can lead to kidney failure if not promptly treated. A bacterial kidney infection can cause permanent damage or can be fatal without proper treatment.
Treatment of Bacterial Kidney Infection in Cats
Bacterial infections of the urinary tract need to be properly treated. Your cat can develop a resistance to antibiotics which can lead to infection that cannot be cleared up. Untreated bacterial infections in the bladder can lead to the more serious condition of kidney infection.
Treatment of kidney bacterial infection in your cat usually requires a long term antibiotic regime for four to six weeks. If you cat has become dehydrated, IV fluids may be required. Surgery may be required is there is an obstruction in the urinary tract. If your cat has kidney stones, they may need to be surgically removed.
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Recovery of Bacterial Kidney Infection in Cats
Recovery of kidney function is possible, depending on the degree of damage to the kidneys. Your veterinarian will perform follow-up urinalysis and cultures after treatment has begun and at the end of the antibiotic regimen. A special diet that is low in protein and low in phosphorus may be recommended. Due to the frequent occurrence of kidney problems in older cats, regular blood and urine screenings are recommended after your cat reaches 7 years of age. 
Be sure to administer medications as prescribed by your veterinarian and keep all follow-up appointments. Do not hesitate to contact your veterinarian with any questions or concerns. Call your veterinarian’s office if your cat does not appear to be responding to the treatment, continues to be lethargic or is not eating or drinking. 
For home management, provide multiple litter boxes in your home. A rule of thumb is one more litter box than the number of cats you have in your home. Encourage your cat to drink water and provide water sources throughout your home. Giving your cat canned food can increase his water intake. Prescription diet food may contain essential fatty acids and antioxidants to help maintain a healthy urinary tract.
Bacterial kidney infections can be expensive to treat. If you suspect your cat has a bacterial kidney infection or is at risk, start searching for pet insurance today. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like PetPlan and Trupanion. Find the “pawfect” plan for your pet in just a few clicks!
Bacterial Kidney Infection Average Cost
From 540 quotes ranging from $200 - $1,200
Average Cost
$400
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Bacterial Kidney Infection Questions and Advice from Veterinary Professionals
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domestic short hair
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Tk
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1 Year
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Urinating Outside Litterbox
Throwing Up
Trying To Urinate
Cry
I have exhausted every option I was told about, including carecredit, scratchpay, and financial assistance programs. I can't get my cat to a vet until Friday morning when my paycheck comes through to my account. My male cat is crying trying to pee and i havent seen him actually get anything out since last night about 10 hours ago. He threw up this morning and I am terrified that he has a blockage. Is there absolutely anything I can do at home until I have the ways to get him to the vet?
Aug. 22, 2018
Answered by Dr. Michele K. DVM
0 Recommendations
There is absolutely nothing that you can do at home for this problem, and TK is suffering terribly if he has a urinary blockage. The kindest thing that you may be able to do for him is to take him to a veterinarian and sign ownership over so that they can humanely euthanize him. That sounds very harsh, I know, but a urinary blockage is a terrible way to die, and it is fatal if not treated. I genuinely hope that something else is going on with him, but he needs help immediately. If you can get friends or family to help, he may have options.
Aug. 22, 2018
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Main Coon
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Fenel
dog-age-icon
5 Years
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1 found this helpful

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1 found this helpful

My pet has the following symptoms:
Dehydration,Lose Weigh,High Bun
Hello,2 months ago i took my cat to my friends house for 5 days and she didn't eat food like before and became depressed and vomited some worms. the vet checked her and took blood test,she has high BUN and ceratenine,dehydrated body and high WBC and RBC. we tried serum therapy for a month and the result became less BUN and ceratenine,and use antibiotic(Ampicillin)for 10 days and anti parasite for 3 days.we did sonography from her kidney (the size of them were normal ) and checked FIV and FELV kit both of them were negative. 4 doctor visit her but no one knows her problem ,she is too weak (less than 2 kilos ) now and cant walk ,her stool is dark and her eyes are become strange.
June 29, 2018

1 Recommendations
It is difficult to say what the specific cause of the increased white blood cells, red blood cells, BUN and creatinine are; however infections, inflammatory disease and autoimmune diseases are possibilities. Dietary management is a good starting point if not done already ensuring that Fenel is on a low quantity but high quality protein diet and received plenty of fluids. Further testing may be useful including a kidney needle aspirate to see the types of cells present. Regards Dr Callum Turner DVM
June 29, 2018
Thank you for answering. She used to eat renal food,but unfortunately she doesn't eat now And because of losing weigh we can’t continue serum teraphy ( she hasn’t acceptable blood vessel ). What should I do now ? She is not well at all
June 29, 2018
Fenel's Owner
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short haired
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Marley
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20 Years
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0 found this helpful

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0 found this helpful

My cat has been peeing in her sleep. She’s not experiencing any pain. In the past she has had painful urination on and off. When it’s painful I’ve taken her to the vet. They’ve given her an antibiotic shot and it goes away. I’m thinking I should probably take her to the vet again. She’s had 2 shots this year.
June 26, 2018
0 Recommendations
There are various different causes for urination while sleeping and may be just age related incontinence, however without examining Marley I cannot say for certain. You should return to your Veterinarian for urinalysis and treatment as required, I cannot confirm if this is due to another infection or something else. Regards Dr Callum Turner DVM
June 27, 2018
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short hair
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Simon
dog-age-icon
8 Years
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7 found this helpful

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7 found this helpful

My pet has the following symptoms:
Excessive Urination
My 8 year old has been excessively drinking and peeing. A urine test showed high levels of bacteria. Was put on clavamox for 2 Improved but within 24 hours symptoms returned. Went back for another urine and bacteria is back. Was told to stop antibiotics for 5 days to get a needle extraction to pinpoint exact bacteria. Is this sound advice? To wait 5 days without anything sounds painful.
June 7, 2018

Answered by Dr. Michele K. DVM
7 Recommendations
I think that your veterinarian is trying to get an accurate urine sample to send off for culture, and Simon does have to be off of antibiotics for a period of time to have relevant test results. It may be worth having some lab work done as well if blood work wasn't done, to make sure that his kidneys aren't the source of the problem. Once they get the needle sample, he can be put back on Clavamox, if that helped, until the actual results come in - the antibiotic may change at that point, but if the Clavamox makes him more comfortable, there isn't anything wrong with doing that.
June 7, 2018
Thank you. Blood work came back normal. Is the excesive drinking, like 4 cups a day and urine like a weeks worth in a day, normal with a bacterial infection? I feel so badly for him.
June 7, 2018
Simon's Owner
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domestic short hair
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Cassie
dog-age-icon
9 Years
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5 found this helpful

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5 found this helpful

My pet has the following symptoms:
12 Hours Of Treatment Little Change
Not eating or drinking, lethargic. Took her to vet and blood work revealed high kidney levels and dehydration. Would not say definitively what the problem was but was leaning towards kidney infection. Started IV fluids and drugs for 24 hours. Can not afford continued vet treatment. Is there anything that can be done at home?
May 26, 2018

Answered by Dr. Michele K. DVM
5 Recommendations
Kidney disease in cats needs very aggressive IV fluid therapy, and always has a guarded prognosis for improvement. 24 hours may not be enough time for treatment, unfortunately. I'm sorry that that is happening to Cassie. Many clinics offer CareCredit to help with unexpected expenses, if that is an option with your clinic.
May 26, 2018
Had a similar situation with sick kitty and limited funds. He had a 24 hours of IV fluids, then did Sub Q at home, but could tell he needed more IV hydration. We compromised and had IV catheter placed and he got IV fluids at the vet during the day. We took him home, flushed IV before bed and first thing in the morning, then took him back to vet for IV fluids. Over the three days he got another 24 hours of IV fluids.
July 26, 2018
Katie G.
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Calico
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Lou
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2 Years
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
No Appetite
Just had our 2ish year old cat(Lou) brought in today with a kidney infection. They are keeping him overnight for 3 nights of fluids and IVs and to be watched over. He just wasn't eating a lot at all and even stopped eating the dry food and would only eat wet food. We were not sure of what caused this but we're just curious as to how serious this is? like I said he is in good hands now for the next few days I was wondering what to possibly expect. Any help would be much appreciated.
Bacterial Kidney Infection Average Cost
From 540 quotes ranging from $200 - $1,200
Average Cost
$400
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