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Home > What is CKD > Acute Kidney Injury



  • Acute kidney injury or AKI (in its worst form known as acute renal failure  or ARF)), is a serious form of kidney failure which usually comes on suddenly and which is often triggered by a particular event or "insult" to the kidneys.

  • AKI is difficult to treat but in some cases the cat may make a full recovery. In other cases, the cat will be left with residual kidney damage.

  • It is possible to have AKI and CKD simultaneously.

What is Acute Kidney Injury?


Acute kidney injury (AKI) is a serious and usually severe form of kidney failure. Unlike CKD, which is chronic and usually develops gradually, AKI usually comes on suddenly and is often triggered by a particular event or "insult" to the kidneys.


Cats with AKI usually have very high bloodwork numbers. If a young previously healthy cat presents with high kidney values, AKI should always be considered.


Cats with CKD may develop AKI on top of the existing CKD, see below.


There is currently some debate over whether early CKD might actually be a slower and less abrupt version of acute kidney injury, according to Is progressive chronic kidney disease a slow acute kidney injury? (2016) Cowgill LD, Polzin DJ, Elliott J, Nabity MB, Segev G, Grauer GF, Brown S, Langston C, van Dongen AM Veterinary Clinics of North America Small Animal Practice 46(6) pp995-1013, which says "chronic kidney disease Stage 1 and acute kidney injury Grade I categorizations of kidney disease are often confused or ignored because patients are nonazotemic and generally asymptomatic. Recent evidence suggests these seemingly disparate conditions may be mechanistically linked and interrelated."


Pet Place has helpful information about acute kidney injury in layman's language.


Pathophysiology of acute kidney injury (2012) Basile DP, Anderson MD & Sutton TA Comprehensive Physiology 2(2) pp1303–1353 explains more about acute kidney injury in humans.


Causes: Pre-Renal, Intrinsic and Post-Renal


There are a number of possible causes of AKI. Like CKD, AKI can be divided into different categories, depending upon the location of the problem:

  • pre-renal ("before" the kidney):

    This usually occurs when something disrupts blood flow to the kidneys.

  • intrinsic ("at" the kidney):

    this means the injury is caused at the kidney itself.

  • post-renal ("after" the kidney): 

    this means the problem has arisen lower down the urinary tract, after the blood has already flowed through the kidneys.

For cats who were previously healthy, the cause I tend to hear about most often is lily toxicity (intrinsic), followed by kidney stones (post-renal).


For cats who already have CKD, the cause I tend to hear about most often is pyelonephritis i.e a kidney infection (intrinsic).


Pre-Renal ("Before the Kidney") Causes

This usually occurs when something disrupts blood flow to the kidneys. Possible causes include low blood pressure, the use of NSAIDs or ACE inhibitors. In some cases, anaesthesia may be a factor, if blood flow to the kidneys is reduced during surgery.


This type of AKI may be reversible if the cause can be treated.


NSAIDs (Non-Steroidal Anti-Inflammatory Drugs)

Non-steroidal anti-inflammatory drugs (NSAIDs) are used as painkillers and anti-inflammatories. Unfortunately cats metabolise this family of medication very poorly, which may cause problems, including acute kidney injury in the worst case.


Meloxicam (Metacam)

Meloxicam is one such NSAID which is available for cats in both injectable and liquid (oral) form. In the USA meloxicam is only approved for use in cats in its injectable form. This is because it is intended to be a one-off treatment as a painkilling injection following surgery. In Europe it is approved in both the injectable version (for one-off use in cats following surgery) and in oral form (for longer term pain management e.g. for use in cats with arthritis).


Unfortunately in some cases meloxicam appears to have caused permanent damage to the kidneys, particularly when it is given to dehydrated cats, with the result that a number of cats seem to have developed acute or chronic kidney problems after taking it.


The risk of this occurring appears to be dosage-related and is not inevitable. Indeed, research is currently being undertaken into whether meloxicam may help slow the progression of CKD.


There is more information on meloxicam in the Treatments section.



Ibuprufen is commonly used in humans, but is not recommended for cats, in whom it may cause AKI.


Veterinary Partner discusses ibuprufen poisoning.


VCA Hospitals discusses how to treat ibuprufen poisoning in cats.


ACE Inhibitors and Angiotensin II Receptor Blockers (ARBs)

These are both heart medications. They help to reduce the work that the heart has to perform to pump blood through the body. Because of this, ACE inhibitors are sometimes used to control hypertension (high blood pressure) (see Hypertension). The main reason they tend to be used for CKD cats, however, is for reducing proteinuria.


It is not uncommon for the kidney values of cats on these medications to worsen when the medication is first begun. This is usually temporary, but may occasionally cause more serious problems, and is of particular concern in dehydrated cats. In Tips for minimizing acute kidney injury in the older pet (2012) Ross SJ Presentation to the Australian Veterinary Association NSW Annual Regional Conference Dr Ross says "Many drugs commonly prescribed to geriatric patients impair autoregulation or interfere with the vasodilatory capacity of the kidney. Such drugs include non-steroidal anti-inflammatory agents (NSAIDs), angiotensin converting enzyme inhibitors (ACEi), and angiotensin receptor blockers (ARBs). It is very important that patients receiving these medications remain well hydrated and have intermittent exams and laboratory assessments to ensure adequate renal function."


Intrinsic ("At the Kidney") Causes

This means the injury is caused at the kidney itself. Possible causes include infections, toxins, cancer or glomerulonephritis.


This is the hardest form of AKI to treat, but it may be possible, depending upon the cause.


Acute kidney disease in  cats: diagnosis, management and prevention (2015) Chew DJ CVC in Kansas City Proceedings discusses AKI.


Acute intrinsic renal failure (AIRF) - causes and prevention (proceedings) (2009) Chew DJ CVC in Kansas City Proceedings explains more about the causes of intrinsic AKI.


See below for information about the different phases of intrinsic AKI.



Most types of lily are extremely toxic to cats. It is not necessary for the cat to nibble on the leaves - even if the cat simply brushes against a tiny amount of pollen, then later licks that area, it can cause AKI.


If your cat is suffering from lily toxicity, don't feel bad that you didn't know the risks (apparently less than 30% of caregivers do know), but do get him or her to the vet as soon as possible, because aggressive treatment may save your cat's life.


Eaater lily toxicosis in cats (1999) Volmer PA Veterinary Medicine 94(4) p331 states that "Vomiting, anorexia, and depression generally occur within two hours of ingestion. The vomiting may subside by 12 hours." Do not assume that if your cat stops vomiting, everything is well, because the damage is continuing even though you cannot see it. The Pet Poison Helpline says "These ingestions are medical emergencies requiring immediate veterinary care. Early decontamination, aggressive intravenous fluid therapy, renal function tests, and supportive care greatly improve the cat’s prognosis. A delay of treatment of more than 18 hours after ingestion generally results in irreversible renal failure."


Do not give up hope if it is more than eighteen hours since your cat ingested lilies. Outcome following gastrointestinal tract decontamination and intravenous fluid diuresis in cats with known lily ingestion: 25 cases (2001-2010) (2013) Bennett AJ & Reineke EL Journal of the American Veterinary Medical Association 242(8) pp1110-16 found that beginning aggressive treatment within 48 hours of ingesting lilies led to a good outcome, with all the cats in this study surviving.


Acute renal failure caused by lily ingestion in six cats (2002) Langston CE Journal of the American Veterinary Medical Association 220(1) pp49-52 reports on six cats who developed AKI after ingesting Easter or tiger lilies. Three cats survived, two died, and one was put to sleep with no treatments being attempted. The chance of survival was lower in cats with reduced or no urination.


In order to prevent problems in the future, do what I do: don't allow lilies in your home. If anybody brings me lilies (my family and friends know better, but not everyone does), I smile politely, thank them, and discreetly dump the lilies straight in the bin outside.


The ASPCA has information on the dangers of lilies.


Cats Protection also has information on lily toxicity.


University of California at Davis discusses lily toxicity in cats.


The Pet Poison Helpline explains which lilies are the most poisonous and what to do if your cat is exposed to lilies.


Antifreeze (Ethylene Glycol)

Antifreeze  contains an ingredient called ethylene glycol which is toxic to cats. Unfortunately cats seem to like the taste of it, so it is a common cause of acute kidney injury.


As with lilies, cats may sometimes appear to recover, but will then become ill once again; therefore it is critical to seek veterinary treatment as early as possible, even if the cat appears to be recovering. Early treatment greatly increases the cat's chances of survival, though sadly, this is very hard to treat successfully.


There are now antifreezes available with a bitter taste added to try to stop cats licking them. There are also "pet-friendly" antifreeze solutions which contain propylene glycol instead of ethylene glycol. Although this is safer, it is not allowed in cat foods because it can cause red blood cell abnormalities. Propylene glycol: educate yourself and your veterinary clients (2015) Scheidegger S DVM360 Magazine explains more about propylene glycol. Ideally, of course, the goal is never to expose your cat to any kind of antifreeze.


Vets Now has some information about ethylene glycol poisoning.


International Cat Care discusses antifreeze poisoning.


Pet Place has three pages of detailed information on antifreeze poisoning.


Washington State University College of Veterinary Medicine has information about antifreeze poisoning.


Kidney Infections (Pyelonephritis)

Cats with acute kidney infections may develop acute kidney injury. Kidney infections may need to be treated with intravenous fluids. A lengthy course of antibiotics is also necessary in most cases. See Pyelonephritis and Urinary Tract Infections for more information.


In my experience kidney infections are the most common cause of AKI in cats who already have CKD. It can be very scary, but it is not necessarily the end because in some cases, successfully treating the infection will lead to the cat making a full recovery. One member of Tanya's CKD Support Group had a cat whose creatinine level was 26 mg/dl at diagnosis. He was diagnosed with pyelonephritis, and although he needed a twelve week course of antibiotics, he made a full recovery.


Post-Renal ("After the Kidney") Causes

This means the problem has arisen lower down the urinary tract, after the blood has already flowed through the kidneys. The usual cause is an obstruction (e.g. kidney stones), which stops urine being passed and causes toxin build up.


If the problem can be resolved, the cat can often make a full recovery.


Renal Calculi (Kidney Stones) and Obstructions

Renal calculi (kidney stones) may cause acute kidney injury by lodging in a ureter (one of the tubes that lead from the kidneys to the bladder) and allowing waste products that would normally be excreted by the bladder to build up in the kidneys — this is called obstructive nephropathy.


The diagnosis can usually be confirmed via ultrasound. The ultrasound may show one small kidney and one enlarged kidney (see renomegaly). See Kidney Stones for more information.


Acute on Chronic Kidney Disease (ACKD)


It is possible to have AKI and CKD simultaneously. This was previously referred to as acute on chronic renal failure or AoCRF, but is now called ACKD.


As the name suggests, acute on chronic kidney disease occurs when already chronically damaged kidneys suffer an acute injury. The most common cause I hear of is a kidney infection (pyelonephritis), though it may also happen for other reasons, e.g. when hyperthyroidism is over-treated. Cats with AoCRF often crash (as may cats with AKI).


It is not always easy to tell whether a cat has AKI or acute on a previously unknown CKD. Differentiation between acute kidney injury and chronic kidney disease (2018) Segev G International Renal Interest Society says "When an animal is presented with acute azotemia, mostly for prognostic projections, the clinician has to assess whether the kidneys had completely normal function before the deterioration, or alternatively, some degree of kidney dysfunction was already present."


Acute on chronic kidney disease in cats: etiology, clinical and clinicopathologic findings, prognostic markers, and outcome (2020) Chen H, Dunaevich A, Apfelbaum N, Kuzi S, Mazaki-Tovi M, Aroch I & Segev G Journal of Veterinary Internal Medicine 22 looked at 100 cats with ACKD attending a veterinary teaching hospital over a two year period. 11% of the cats had stones, 8% had pyelonephritis but no obvious cause could be found in 66% of the cats. Over half (54%) of the cats also had pancreatitis. 58% of the cats survived, 13% died and 29% were euthanised. Cats with stones were more likely to survive.


Feline chronic kidney disease (2015) Grauer GF Today's Veterinary Practice 5(2) pp36-41 lists (page 40) six common causes of AKI in cats with previously stable CKD.


Patient UK explains more about acute on chronic kidney disease in humans.




When your cat is diagnosed with CKD, in hindsight you may realise that your cat was exhibiting subtle signs of illness such as increased drinking and urination, poor appetite and weight loss.


In contrast, since AKI comes on suddenly, there may have been no signs at all of illness previously, so you will probably notice a dramatic change in your cat, though as explained above, sadly this may not happen until a fair amount of damage has already been done.


AKI cats often look lethargic, stop eating and vomit. They may urinate more, less or not at all (not urinating at all is a medical emergency, as AKI is generally).




General Examination

The vet will examine the cat and ask questions about the cat's behaviour and demeanour. Most cats with AKI will have become ill very suddenly, having previously been healthy and of a suitable weight, with a good appetite. Although CKD cats may seem to become ill suddenly if they crash, in most cases there will have been some signs previously, such as weight loss and increased drinking.


Most cats with AKI will be dull, lethargic and unwilling to eat. These signs may also be seen in cats with CKD but as Which is it? Acute renal failure versus chronic kidney disease (2009) Grauer GF CVC in Washington DC Proceedings says, "Clinical signs associated with ARF tend to be severe when compared with those of a patient with CRF and the same magnitude of azotemia."


Most CKD cats exhibit increased urination but cats with AKI may exhibit reduced or no urination.


Blood Tests

Your vet will usually take blood to run tests. A chemistry panel will examine kidney values and other important values, while a complete blood count will check for infection and anaemia.


Cats with AKI will often present with extremely high kidney values, with creatinine often over 10 mg/do USA (850 µmol/L international), although it may even be twice as high as that. 


They usually have metabolic acidosis.


At initial diagnosis, they may have low calcium levels, which may then rise as treatment is begun, to such an extent that they may then become too high.


AKI cats may exhibit reduced urination (which is sometimes the cause of the AKI if there is a reason for it such as kidney stones), and this can cause potassium levels to rise to dangerously high levels (high potassium levels are known as hyperkalaemia).


One relatively common feature with AKI cats is that they do not appear to be anaemic, i.e. their HCT levels will be normal or even elevated.


Other Tests

A urine culture should be performed to check for infection.


It is worth getting an ultrasound performed to see if this can shed some light on the cause. Indeed, ultrasound findings are used in the staging system below to help determine the severity of the AKI.


Ultrasonographic findings in cats with acute kidney injury: a retrospective study (2019) Cole LP, Mantis P & Humm K Journal of Feline Medicine and Surgery 21(6) pp475-480 states that common findings include enlarged kidneys, dilated renal pelvis and fluid.


Enlarged kidneys in particular seem to be quite common in cats with AKI, whereas cats with CKD tend to have small, shrunken kidneys. Enlarged kidneys are particularly common in cats with kidney stones. Which is it? Acute renal failure versus chronic kidney disease (2009) Grauer GF CVC in Washington DC Proceedings says "Unique clinical signs and clinicopathologic findings associated with ARF include enlarged or swollen kidneys...Renal ultrasonography findings in dogs and cats with ARF are usually nonspecific with diffuse normal to slightly hyperechoic renal cortical echotexture. In patients with calcium oxalate nephrosis associated with ethylene glycol ingestion, the renal cortices can be very echodense. Histopathologic examination of renal cortical biopsies from patients with ARF will reveal varying degrees of tubular necrosis. Evidence of tubular epithelial regeneration can be observed as early as three days after the acute insult and is a positive prognostic indicator."


Staging of AKI


Grading of acute kidney injury (2016) Cowgill L The International Renal Interest Society provides a grading system for AKI in cats:



of Disease

Blood Values:

US (mg/dl)

Blood Values:

International (µmol/L)


Clinical Description

Stage 1

Creatinine below 1.6

Creatinine below 140

Non azotaemic AKI or volume-responsive AKI:

- Documented AKI: (historical, clinical, laboratory, or imaging evidence of AKI, clinical oliguria/anuria, volume responsiveness) and/or

- Progressive nonazotemic increase in blood creatinine: ≥ 0.3 mg/dl (≥ 26.4 μmol/l) within 48 hr

- Measured oliguria (<1 ml/kg/h)# or anuria over 6 h

Stage 2

Creatinine between

1.7 and 2.5

Creatinine between

141 and 220

Mild AKI:

- Documented AKI and static or progressive azotemia

- Progressive azotemic: increase in blood creatinine; ≥ 0.3 mg/dl ≥ 26.4 μmol/l) within 48 h),or volume responsiveness

- Measured oliguria (<1 ml/kg/h)# or anuria  over 6 h

Stage 3

Creatinine between

2.6 and 5.0

Creatinine between

221 and 439

Moderate to Severe AKI:

- Documented AKI and increasing severities of azotaemia and functional renal failure


Stage 4

Creatinine between

5.1 and 10.0

Creatinine between

440 and 885

Stage 5

Creatinine over 10.0

Creatinine over 880


Each stage is also sub-staged depending upon whether the cat is producing no urine or only a small amount of urine and whether the cat needs renal replacement therapy.


IRIS points out that things can change suddenly with AKI, so these stages are a "moment in the course of the disease." Do not give up hope if your cat is in the higher stages, things may change with appropriate treatment (see below).




It is worth trying to treat a cat with AKI. Clinical staging of acute kidney injury (2012) Cowgill LD Presentation to the Advanced Renal Therapies Symposium, NYC  says (page 81) "Animals recognized and managed with IRIS AKI Stages I and II may regain adequate renal function within 2 to 5 days, forestalling life-threatening azotemia and electrolyte disorders and usually need only short-term support."


Even for cats in the higher stages, it is worth trying treatment because as Grading of acute kidney injury (2016) Brown SA The International Renal Interest Society says, "the “grade” represents a moment in the course of the disease and is predicted to change as the condition worsens, improves, or transitions to CKD."


Azotemia and acute kidney injury (2016) Grauer GF & Guess S Clinician's Brief Oct 2016 provides a management tree for AKI cats.


Hospitalisation and Fluid Therapy

Most cats with AKI require a number of days of hospitalisation on intravenous fluids. These help to rehydrate the cat, flush out toxins, and correct electrolyte balances, such as elevated potassium levels.


Acute uremia in cats (2008) Ross S Veterinary Focus 18(2) says "Critical to initial management are the establishment and maintenance of euvolemia. Many patients are signficantly dehydrated at presentation and rapid restoration of extracellular volume and renal perfusion corrects Pre-renal azotemia and helps prevent further ischemic renal damage. Intravenous (IV) crystalloid rates are calculated to correct extracellular fluid deficits."


Most cats benefit from lactated ringers solution or PlasmaLyte. Although sodium chloride may be necessary initially for cats with high potassium levels, it is not a good ongoing choice because it may cause sodium levels in the cat's body to rise too high. Acute kidney injury in dogs and cats (2011) Ross L Veterinary Clinics of North America Small Animal Medicine 41 pp1-14 says "An isotonic, polyionic fluid, such as lactated Ringer’s solution (LRS) or Plasma-Lyte A may be administered initially. If hyperkalemia is present or suspected because of oliguria or anuria, a potassium-free fluid, such as 0.9% sodium chloride, may be indicated. Following rehydration, the type of fluid should be adjusted based on the animal’s fluid and electrolyte status. Continued administration of fluids high in sodium relative to maintenance needs may lead to hypernatremia, especially in cats."


Do not accept just one day of treatment, most cats need several days as a minimum.


Various medications may also be given to treat concurrent problems such as high potassium levels, metabolic acidosis or vomiting.


Other treatments may also be needed, as follows:


AKI Associated with the Use of NSAIDs

The Treatments section gives details of the recommended protocol for treating acute kidney injury associated with the use of meloxicam.



Cats with pyelonephritis (kidney infections) will require a lengthy course of antibiotics.


Stent or Subcutaneous Ureteral Bypass (SUB)

Cats with kidney stones usually have calcium oxalate stones. These cannot be dissolved through diet, so are usually treated initially with IV fluids and diuretics in an attempt to flush the stones out. If this does not work, other treatments need to be considered.


See the Kidney Stones page for more information on other treatments, including stents and SUBs.


Urinary tract blockages may also be caused by the opposite problem, struvite crystals. This type of blockage also needs to be treated with hospitalisation on IV fluids and in some cases may require surgery, but following the initial crisis it can often be managed with dietary modifications at home.


Dialysis or Renal Replacement Therapy

For cats who do not respond to the standard AKI treatments, dialysis or renal replacement therapy may be considered.


Acute uremia in cats (2008) Ross S Veterinary Focus 18(2) says "Hemodialysis or peritoneal dialysis are often the only options for acutely uremic patients unresponsive to appropriate, aggressive medical management. Indications for initiating dialysis include severe hyperkalemia, volume overload refractory to fluid restriction and diuretics, intractable uremia and (especially for hemodialysis) acute toxicities and drug overdoses. The metabolic stability provided by dialysis provides time to determine the cause of renal dysfunction, giving clients better prognostic data. Ideally, dialysis creates a window of stability long enough to enable renal recovery. In the earlier stages of progressive azotemia, hemodialysis may also be initiated proactively to forestall or preclude development of uremia. This approach improves quality of the life and owner satisfaction, and facilitates overall case management."


Unfortunately these treatments are extremely expensive and only available at a limited number of facilities, so are out of the reach of many people.



A drug called fenoldopam, which is normally used to treat severe hypertension in humans, might be of some use in treating cats with AKI.


Cats suffering from AKI may exhibit oliguria (limited urine output). Dogs and humans with this problem are usually treated with a drug called dopamine, but this has not been particularly effective in cats because they have fewer receptors for this drug.


Diuretic effects of fenoldopam in healthy cats (2006) Simmons JP, Wohl JS, Schwartz DD, Edwards HG & Wright JC Journal of Veterinary Emergency and Critical Care 16(2) pp96–103 found that fenoldopam appears to increase blood flow and urine output in healthy cats.


Administration of fenoldopam in critically ill small animal patients with acute kidney injury: 28 dogs and 34 cats (2008-2012) (2015) Nielsen LK, Bracker K & Price LL Journal of Veterinary Emergency and Critical Care 25(3), pp396–404 examined the use of fenoldapam in cats with AKI. It found that the most common side effect, seen in 23% of AKI cats given fenoldopam, was low blood pressure. The study concludes that "0.5 μg/kg/min in cats appeared relatively safe but was not associated with improvement in survival to discharge, length of hospital stay, or improvement in renal biochemical parameters when compared to patients with AKI not receiving fenoldopam."


I have not heard from anybody who has used fenoldopam in an AKI cat as yet.


Phases of Acute Kidney Injury


In Acute uremia in cats (2008) Ross S Veterinary Focus 18(2) Dr Ross says that what happens in intrinsic AKI (see above) can be divided into four phases, though not all cats will experience all the stages:


Phase 1: Initiation

The cat experiences the damaging event, such as eating lilies. This phase may not be visible, but if you are able to take action during this phase (e.g. if you see your cat eating lilies and seek immediate veterinary help), this increases your cat's chances of recovery.


Phase 2: Extension

The damage continues, the cat's GFR reduces and urinary changes may be seen, such as reduced urination.


Phase 3: Maintenance

The damage continues and symptoms may finally appear, leading to the cat being taken to the vet and treatment being instigated.


Phase 4: Recovery

The cat starts to improve, with increasing GFR and other improvements. This may happen suddenly or be a gradual process lasting several months.




The prognosis depends in part upon the cause of the AKI, how quickly treatment is begun, and other factors such as the general health of the cat.


It can be harder to treat cats in Stages 4 and 5. On page 81 of Clinical staging of acute kidney injury (2012) Presentation to the Advanced Renal Therapies Symposium, NYC , Dr L Cowgill states "Those with higher IRIS Stages of AKI at presentation or whose IRIS AKI stage progresses during hospitalization may require weeks of supportive care before the onset of renal repair. Animals with severe kidney failure, IRIS AKI Stage IV or V, may die within 5 to 10 days despite appropriate conventional management unless supported with renal replacement therapy for an indefinite time."


Don't forget though, as Grading of acute kidney injury (2016) Brown SA The International Renal Interest Society says, "unlike the IRIS staging for CKD, grading of AKI would not imply the kidney disease is stable or at steady-state. On the contrary, the “grade” represents a moment in the course of the disease and is predicted to change as the condition worsens, improves, or transitions to CKD." So your cat may move out of Stage 4 or 5 even if you can only provide more traditional fluid therapy.


Although AKI can be difficult to treat, if the cat does survive the initial crisis, he/she can often regain much or sometimes all of his/her normal kidney function. However, sometimes cats who experience AKI will have some residual damage, and will be left with CKD. Differentiation between acute kidney injury and chronic kidney disease (2018) Segev G International Renal Interest Society states "animals that recover from AKI have to be monitored prospectively as CKD Stage 1 patients, since complete clinical recovery, as well as normalization of serum creatinine concentration, do not rule out residual chronic kidney damage."


Tips for minimizing acute kidney injury in the older pet (2012) Ross SJ Presentation to the Australian Veterinary Association NSW Annual Regional Conference says "Overall, the long-term prognosis for patients surviving episodes of acute uremia is fair to good depending on the underlying etiology. Early diagnosis and appropriate intervention improve survival and minimize the potential of persistent renal injury."


Grading of acute kidney injury (2016) Cowgill L The International Renal Interest Society provides information on five patients with AKI (see the table). This includes a cat (Example 3) with pyelonephritis who improved greatly with appropriate treatment. Example 5 is a cat with lily toxicity who made a full recovery.


In The laboratory diagnosis of feline kidney disease (2008) Heiene R Veterinary Focus 18(2) pp16-22, Dr Heiene states "cats can sometimes, especially in cases of acute kidney injury secondary to obstructive FLUTD, develop creatinine values of 1600-1800 μmol/L (20.98-23.6 mg/dL) and yet recover."


One member of Tanya's CKD Support Group had a cat with AKI whose creatinine level was 26 mg/dl at diagnosis. He was diagnosed with pyelonephritis, and although he needed a twelve week course of antibiotics, he made a full recovery.


For cats with acute on chronic kidney disease, it may be possible to resolve the AKI and return to the status quo of CKD. Tips for minimizing acute kidney injury in the older pet (2012) Ross SJ Presentation to the Australian Veterinary Association NSW Annual Regional Conference says "expedient treatment of factors causing acute decompensation of CKD (e.g., pyelonephritis, hypovolemia) may permit reversion to pre-crisis levels of function."


Although AKI is trickier to treat than CKD, as with CKD I would try treatment and see how you get on, and remember, as Dr Ross says in Acute uremia in cats (2008) Veterinary Focus 18(2), recovery may be sudden and relatively quick, or may be gradual and require several months of treatment.




Obviously you want to avoid exposing your cat to toxins such as lilies or antifreeze.


If you are using medications such as NSAIDS or benazapril, ensure your cat is well hydrated and that you begin with a modest dose.


Tips for minimizing acute kidney injury in the older pet (2012) Ross SJ Presentation to the Australian Veterinary Association NSW Annual Regional Conference discusses ways to avoid AKI.


Protecting the kidneys from acute uremic crisis (2007) Polzin DJ Delaware Valley Academy of Veterinary Medicine pp46-47 suggests ways to reduce the risk of AKI.





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This page last updated: 31 October 2020


Links on this page last checked: 20 June 2020









I have tried very hard to ensure that the information provided in this website is accurate, but I am NOT a vet, just an ordinary person who has lived through CKD with three cats. This website is for educational purposes only, and is not intended to be used to diagnose or treat any cat. Before trying any of the treatments described herein, you MUST consult a qualified veterinarian and obtain professional advice on the correct regimen for your cat and his or her particular requirements; and you should only use any treatments described here with the full knowledge and approval of your vet. No responsibility can be accepted.


If your cat appears to be in pain or distress, do not waste time on the internet, contact your vet immediately.



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This site was created using Microsoft software, and therefore it is best viewed in Internet Explorer. I know it doesn't always display too well in other browsers, but I'm not an IT expert so I'm afraid I don't know how to change that. I would love it to display perfectly everywhere, but my focus is on making the information available. When I get time, I'll try to improve how it displays in other browsers.


This site is a labour of love. Please do not steal from me by taking credit for my work.

If you wish to link to this site, please feel free to do so. Please make it clear that this is a link and not your own work. I would appreciate being informed of your link.