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 Practice46(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."
Differentiation between acute kidney injury and
chronic kidney disease (2022) Segev G International Renal
Interest Society discusses the differences between AKI and CKD, saying
"these seemingly different conditions may be mechanistically linked and
interrelated, and the main difference between them is the rate of disease
progression."
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 medications very poorly, which may cause
problems, including acute kidney injury in the worst case.
Meloxicam (Metacam)
Meloxicam is one such NSAID which isavailable 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.
ACE Inhibitorsand
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."
Ibuprufen
Ibuprufen is commonly used in humans, but is not recommended for cats, in
whom it may cause AKI.
See
below for information about the different phases of intrinsic AKI.
Lilies
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.
Easter lily toxicosis in cats
(1999) Volmer PA Veterinary Medicine94(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."
Acute renal failure caused by lily ingestion in six
cats (2002) Langston CE Journal of the American Veterinary
Medical Association220(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.
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.
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.
Aminoglycosides
Antibiotics in the aminoglycoside family, such as
gentamicin, are associated with AKI. These antibiotics are
rarely used in cats but if your cat needs to take one, ensure your
vet follows the guidelines in
Preventing aminoglycoside-induced AKI
(2022) International Renal Interest Society,
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 (pyelonelonephritis), 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 (which is presumably what the cats in the Beeston
study had).
Differentiation between acute kidney injury and
chronic kidney disease (2022) 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." The article has a table showing
possible differences between cats with CKD and AKI.
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 Medicine22
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 Practice5(2)
pp36-41
lists (page 40) six common causes of AKI in
cats with previously stable CKD.
Symptoms
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 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
crash.
AKI cats may urinate more,
less or not at all. Not urinating at all is a medical emergency,
but then so is AKI itself.
Diagnosis
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 also appear to become ill suddenly if they
crash, in most cases there will have been some
subtle 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.
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.
Differentiation between acute kidney injury and
chronic kidney disease (2022) Segev G International Renal
Interest Society says
"high phosphorous to creatinine ratio is more suggestive of AKI.
Calcium concentration tends to be normal to low in animals with AKI, while
in animals with CKD, calcium concentration tends to be normal to 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 many of them do not appear to be anaemic, i.e. their
HCT
levels will be normal or even elevated.
Urinalysis
A urine culture should be performed to check
for infection.
Ultrasound
Try to have an
ultrasound performed to see if this can shed some light on the cause.
Ultrasound findings are also used in the staging system
below to help determine the severity of the AKI.
Differentiation between acute kidney injury and
chronic kidney disease (2022) Segev G International Renal
Interest Society states "typical ultrasonographic changes
characterizing CKD include small kidneys with irregular margins,
hyperechoic cortices and poor corticomedullary differentiation, whereas in
AKI, the kidneys maintain normal architecture and often are enlarged with
hyperechoic cortexes."
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:
Stage
of Disease
Creatinine
US (mg/dl)
Creatinine:
International
(µmol/L)
Clinical Description
Stage 1
Below 1.6
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
Between
1.7 and 2.5
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
Between
2.6 and 5.0
Between
221 and 439
Moderate to Severe AKI:
- Documented AKI and increasing severities
of azotaemia and functional renal failure
Stage 4
Between
5.1 and 10.0
Between
440 and 885
Stage 5
Over 10.0
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).
Treatments
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) Cowgill L 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."
Most cats with AKI require several 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 Focus18(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
[high potassium levels in the blood] 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."
Acute kidney injury in cats: part three - management
(2014) Finch N Veterinary Times states "Many
cats with AKI develop hypertension, with a recent study reporting 38 per
cent of cats to have a systolic blood pressure greater than 150mmHg."
Therefore ensure your cat's blood pressure is monitored during
hospitalisation.
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.
Antibiotics
Cats with
pyelonephritis (kidney infections) will
usually 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.
Acute uremia in cats
(2008) Ross S
Veterinary Focus18(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.
Fenoldopam
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 Care16(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 Care25(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
Acute uremia in cats
(2008) Ross S
Veterinary Focus18(2) states 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.
Prognosis
Prognosis: AKI
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) Cowgill L 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 (2022)
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.
The laboratory diagnosis of feline kidney disease
(2008) Heiene R Veterinary Focus18(2) pp16-22 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.
Although AKI is trickier to treat than CKD, as with CKD I would try
treatment and see how you get on, and remember, as
Acute uremia in cats (2008) Ross S Veterinary
Focus18(2) says, recovery may be sudden and relatively quick, or
may be gradual and require several months of treatment.
Differentiation between acute kidney injury and
chronic kidney disease (2022) Segev G International Renal
Interest Society
says "animals that recover from AKI has [sic] to be monitored
prospectively as IRIS 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
"expedient treatment of factors
causing acute decompensation of CKD (e.g., pyelonephritis, hypovolemia)
may permit reversion to pre-crisis levels of function."
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 Medicine22
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.
Machine-learning algorithm as a prognostic tool in
non-obstructive acute-on-chronic kidney disease in the cat
(2021) Renard J, Faucher MR, Combes A, Concordet D & Reynolds BS
Journal of Feline Medicine and Surgery 23(12)
pp1140-1148 looked at various factors in such cats and found that
creatinine was a good clue to chances of survival, with cats with
creatinine above 1043 µmol/l (11.79mg/dl) at seven days or above 566 µmol/l
(6.4mg/dl) at 30 or 90
days having a less promising prognosis. However, it is worth noting that
even cats with a creatinine level close to 566 µmol/l
(6.4mg/dl)
were more
likely to survive than not. One cat had a creatinine level of
1398 µmol/l (15.8 mg/dl) two days after admission to hospital, with no
obvious cause of the ACKD such as an infection, yet she was still alive
985 days later, when the study ceased follow-up.
I would try to treat if possible and
see how you get on.
Prevention
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.
TREATING YOUR CAT WITHOUT VETERINARY ADVICE CAN BE
EXTREMELY DANGEROUS.
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.
This site was
created using Microsoft software, and therefore it is best viewed in
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