Renal disease can be hiding in plain sight... IDEXX SDMATM is a breakthrough in the early and specific diagnosis of renal disease in cats and dogs.

IDEXX SDMATM

Early, Specific & Proven

Kidney disease is one of the most common conditions seen in older dogs and cats, with very serious health consequences. In time, up to one in three cats and one in ten dogs will develop some form of renal disease.

Identifying disease sooner gives you more time to intervene and formulate a management protocol for each animal. Such early diagnosis is now available to all vets through a revolutionary new kidney function test: IDEXX SDMATM.

SDMA has been shown to be a more sensitive and specific biomarker of renal function compared to creatinine. Since the test was made available to practices across Australia, more than 50,000 tests have been run and veterinarians are now seeing more than 2X the amount of early kidney disease detected by creatinine alone*.

An SDMA result above 14ug/dL indicates reduced renal function. The use of IDEXX SDMATM as part of the minimum database permits the diagnosis of renal disease prior to the onset of clinic signs.
The importance of this has been the topic of recent studies and is now understood to deliver an opportunity to slow the progression of chronic kidney disease.

* Data on file at IDEXX Laboratories


This is what Dr Alicia Fagella, Emergency & Critical Care Specialist had to say:

"It makes sense to run SDMA on all patients, since it provides such an early indicator for disease. When an elevated SDMA result is observed in an apparently healthy animal, we see this as cause to investigate further and it has helped us improve as a hospital team in assessing the whole picture, for each patient."


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What is IDEXX SDMATM?


Content developed for the United Kingdom. IDEXX SDMATM is available in Australia.

IRIS - International Renal Interest Society

"IRIS recognizes that SDMA is a new biomarker for renal dysfunction that can allow for earlier detection of chronic kidney disease…SDMA has the potential to expand diagnostic insight and therapeutic opportunities for veterinarians caring for pets with this critical disease."

Astrid M. van Dongen - President of the IRIS Board and Associate Professor of Internal Medicine/Nephrology, Faculty of Veterinary Medicine, Utrecht University

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The stages of Chronic Kidney Disease

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Featured FAQ

SDMA has been validated for use in dogs and cats only. Further work is being done to understand the medical utility and applicable reference intervals in other species. IDEXX will keep registered members informed as and when the test becomes validated for additional species.
Compared to the gold standard liquid chromatography mass-spectrometry which delivers an extended time to results. IDEXX SDMATM results will be included with selected routine chemistry profile results and will not impact their turnaround time. Stand-alone IDEXX SDMATM results will be provided daily.
The reference interval for dogs and cats is the same; 0–14 µg/dL. Reference intervals were established following the Clinical and Laboratory Standards Institute (CLSI) guidelines for determining reference intervals.

Early detection of CKD



How can I access IDEXX SDMATM?

All IDEXX canine and feline recommended profiles will have IDEXX SDMATM included AT NO EXTRA COST. Use the test code of your choice.

The IDEXX SDMATM renal screening panel is a standalone option incorporating IDEXX SDMATM and Creatinine. Use test code IRSP.

Order IDEXX SDMATM using VetConnect®Plus Online Lab Requests.



How do I interpret my IDEXX SDMATM results?

Watch this quick video on why an IDEXX SDMATM result is of such value to your diagnostic workup.

Review the research to understand what the results mean for your patients.

Consult with our internal medicine specialists on your case reports. Request a consult via VetConnect®Plus or call

1300 44 33 99


IDEXX SDMATM is a new test to help evaluate kidney function. It increases earlier than creatinine in the majority of animals with chronic kidney disease. Unlike creatinine, IDEXX SDMATM is not impacted by lean body mass. IDEXX SDMATM and Creatinine should be interpreted together, along with a urinalysis to properly assess kidney health.

IDEXX SDMATM is a sensitive and specific biomarker of kidney function, so we recommend reviewing your patient’s history, physical examination findings, and other laboratory results for any evidence of kidney disease. If a urinalysis has not been performed, then performing a urinalysis and a UPC Ratio is the next step in the diagnostic plan.


  • IDEXX SDMATMCREATININE
  • If both SDMA and creatinine are well within the reference interval, then kidney function is likely good. As IDEXX SDMATM and/or creatinine approach the upper end of the reference interval, early kidney disease cannot be ruled out.
  • If SDMA is increased but creatinine is within the reference interval, then early kidney disease is likely. Alternatively, if the patient is poorly muscled, creatinine may be "falsely" decreased. Urine specific gravity should support some loss of urine concentrating ability. A complete urinalysis/ UPC Ratio should be performed to evaluate for proteinuria and other evidence of kidney disease.
  • If SDMA is within the reference interval and creatinine is increased, then kidney disease is possible. However, SDMA may be less impacted by dehydration than creatinine. Assess hydration status and urine specific gravity for evidence of dehydration or if there is loss of urine concentrating ability to support early kidney dysfunction.
  • If both SDMA and creatinine are increased, then kidney function is likely impaired. Evaluate urine specific gravity to confirm loss of urine concentrating ability. A complete urinalysis and UPC Ratio should be performed to evaluate for proteinuria and other evidence of kidney disease.


What constitutes a significant increase in SDMA?

Any increase of SDMA above the reference interval (greater than 14 µg/dL) is considered meaningful. Most animals with early kidney disease have a SDMA of 15-20 µg/dL. Since SDMA increases as kidney function decreases, an SDMA concentration greater than 20 µg/dL is typically seen in more advanced disease, along with an increased creatinine concentration. Less than 1% of all results will be above 50 µg/dL and the linearity of the assay is up to 100 µg /dL.


Does an increased IDEXX SDMATM mean that the patient has renal failure?

Renal failure is an outdated term. Current terminology for acute disease is acute kidney injury (AKI). Current terminology for chronic disease is chronic kidney disease (CKD) and the International Renal Interest Society (IRIS) staging system should be used to stage chronic stable disease from stage 1 through stage 4. Please see the IRIS guidelines for more information. IDEXX SDMATM offers another tool for recognising dogs and cats with early CKD.



IMM Protocol

With its key attributes as an early, specific and sensitive renal biomarker, IDEXX SDMATM is a valuable new tool in the diagnosis of kidney disease for cats and dogs and is demonstrating an ability to identify the early loss of renal function in twice as many cases as creatinine alone*.

Once you have run the IDEXX SDMATM test, you will be in a position to identify disease early if the result is elevated. The IMM protocol - Investigate, Manage and Monitor is your easy to follow guide, on what to do next.



* Data held on file at IDEXX Laboratories.

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How will SDMA help your practice and the profession?

IDEXX SDMATM is a NATA accredited test, endorsed by IRIS and adopted by specialists. It affords practitioners an opportunity to practice a new standard of care and deliver an improved client experience. Here is Dr Lydia Hambrook, Small Animal Medicine Specialist sharing her experience:



Better Medicine

Early idenfication opens the door for early intervention and improved patient outcomes.



Client Loyalty

Enhance the client interaction by evidencing additional value to the vet visit.



Practice Profits

Early identification opens up avenues for supportive OTC product sales, revisits and further investigation where appropriate.

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Frequently asked questions

Symmetric dimethylarginine (SDMA) is a methylated arginine amino acid, a very sensitive and specific biomarker for early detection of kidney disease.
SDMA increases earlier than creatinine in dogs and cats with kidney disease. It is also not impacted by lean body mass, making it a more sensitive test for assessing kidney function in older and underweight animals.
A published study in cats found the sensitivity of IDEXX SDMATM to be 100% and the specificity to be 91% when compared to the gold standard of GFR.
SDMA is excreted from the kidneys; therefore, as kidney function or GFR decreases, SDMA increases. Studies have shown a very strong correlation between SDMA and GFR (R2 of 0.82 in cats; R2 of 0.85 in dogs). The benefit of using SDMA along with creatinine, which typically increases above the reference interval only after a 75% reduction in GFR, is that SDMA increases when there is on average a 40% decrease in GFR. In some cases, SDMA increases earlier when there is 25% reduction of GFR, representing 25% loss of kidney function.
The reference interval for dogs and cats is the same; 0–14 µg/dL. Reference intervals were established following the Clinical and Laboratory Standards Institute (CLSI) guidelines for determining reference intervals.
SDMA has been validated for use in dogs and cats only. Further work is being done to understand the medical utility and applicable reference intervals in other species. IDEXX will keep registered members informed as and when the test becomes validated for additional species.
Please consult the IRIS renal staging guidelines for more information on appropriate therapeutic options or call one of our Internal Medicine Consultants on 1300 44 33 99 to discuss your case.
The IDEXX SDMATM test can be run on serum, lithium heparin plasma or EDTA plasma. The preferred specimen type is serum and this should be used wherever practicable. Please note that the whole blood separators used in the Catalyst in-clinic chemistry analysers are not to be used for submission to the laboratory and a standard blood collection tube should be used.
IDEXX SDMATM is stable for 4 days at room temperature and 14 days refrigerated. It is also stable for years in specimens that remain frozen and do not undergo freeze thaw cycles.
Just like some other analytes SDMA may be affected by sample artefact such as moderate to marked haemolysis and/or lipaemia, and if the interference is marked it is possible no result may be attained. If an SDMA result is obtained in the face of such artefacts that does not correlate with creatinine, urine concentration or clinical signs, the SDMA should be remeasured on a non haemolysed/lipaemic sample.
Compared to the gold standard liquid chromatography mass-spectrometry which delivers an extended time to results. IDEXX SDMATM results will be included with selected routine chemistry profile results and will not impact their turnaround time. Stand-alone IDEXX SDMATM results will be provided daily.
Currently, IDEXX SDMATM is a reference laboratory-only test. IDEXX has a long history of introducing new tests at our reference laboratory first and then introducing them in-house (e.g., the SNAP® Feline proBNP Test and the Catalyst® Fructosamine Test). At present, all in-house chemistry customers can easily order a stand-alone IDEXX SDMATM test at IDEXX Reference Laboratories.
Any increase of SDMA above the reference interval (greater than 14 µg/dL) is considered meaningful. Most animals with early kidney disease have a SDMA of 15-20 µg/dL. Since SDMA increases as kidney function decreases, an SDMA concentration greater than 20 µg/dL is typically seen in more advanced disease, along with an increased creatinine concentration. Less than 1% of all results will be above 50 µg/dL and the linearity of the assay is up to 100 µg /dL.
Renal failure is an outdated term. Current terminology for acute disease is acute kidney injury (AKI). Current terminology for chronic disease is chronic kidney disease (CKD) and the International Renal Interest Society (IRIS) staging system should be used to stage chronic stable disease from stage 1 through stage 4. Please see the IRIS guidelines for more information. IDEXX SDMATM offers another tool for recognising dogs and cats with renal disease.
IDEXX SDMATM is a sensitive and specific biomarker of kidney function, so we recommend reviewing your patient’s history, physical examination findings, and other laboratory results for any evidence of kidney disease. If a urinalysis has not been performed, then performing a urinalysis and a UPC Ratio is the next step in the diagnostic plan.

  • IDEXX SDMATM: N –  CREA: N
    If both IDEXX SDMATM and creatinine are well within the reference interval, then kidney function is likely good. As SDMA and/or creatinine approach the upper end of the reference interval, early kidney disease cannot be ruled out. Evaluate urine specific gravity and urinalysis/UPC Ratio for proteinuria to help confirm there is no other evidence of kidney disease
  • IDEXX SDMATM: –  CREA: N
    If IDEXX SDMATM is increased but creatinine is within the reference interval, then early kidney disease is likely. Alternatively, if the patient is poorly muscled, creatinine may be "falsely" decreased. Urine specific gravity should support some loss of urine concentrating ability. A complete urinalysis/UPC Ratio should be performed to evaluate for proteinuria and other evidence of kidney disease.
  • IDEXX SDMATM: N – CREA:
    If IDEXX SDMATM is within the reference interval and creatinine is increased, then kidney disease is possible. However, SDMA may be less impacted by dehydration than creatinine. Assess hydration status and urine specific gravity for evidence of dehydration or if there is loss of urine concentrating ability to support early kidney dysfunction
  • IDEXX SDMATM: – CREA:
    If both IDEXX SDMATM and creatinine are increased, then kidney function is likely impaired. Evaluate urine specific gravity to confirm loss of urine concentrating ability. A complete urinalysis and UPC Ratio should be performed to evaluate for proteinuria and other evidence of kidney disease.
SDMA concentrations have been noted to trend slightly higher in puppies and kittens. A result which is marginally above the reference interval in the absence of other signs of kidney disease should be monitored over time to determine if this is the result of biological variation. If the elevation is persistent, or other markers of kidney disease are present, further investigation and management is warranted.
Early diagnosis provides the opportunities to:
Investigate for an underlying cause, especially more treatable conditions such as infection and obstruction, and to IRIS substage the CKD for proteinuria and hypertension. Manage or treat those causes, attending to hydration, proteinuria and hypertension, with consideration for initiating kidney-supportive diet and drugs as indicated, and implementing practices to avoid future insults to the kidneys, e.g., taking precautions with prescribed drugs and when anesthetizing pet.
Monitor the patient as an individual. The frequency of recheck visits will depend on clinical status, whether an underlying disease was identified and what treatments were initiated. An initial recheck 2 weeks after kidney disease is first suspected or identified would be reasonable to determine if disease is stable or progressing. After this initial recheck, in a stable animal with early CKD and no hypertension or proteinuria, a recheck in 2-3 months would be reasonable.
IDEXX SDMATM and creatinine are complementary. IDEXX SDMATM will not replace creatinine; it is another, more sensitive tool to evaluate kidney function. Creatinine is needed for International Renal Interest Society (IRIS) staging of CKD, so it will continue to be important for clinical characterization of CKD patients.
It may be helpful to point out that a urinalysis is a very inexpensive test, relative to the potential information gained, with a low cost/high benefit ratio. A urinalysis should be part of the minimum database for all routine preventive healthcare screens and in sick dogs and cats. Patients with kidney disease may have few clinical signs, but findings on the urinalysis can provide supportive evidence of the presence of kidney disease and perhaps help determine aetiology. Inappropriately concentrated (dilute) urine is one of the most consistent findings when kidney function is reduced by about 67%, when SDMA would typically be increased, and before azotaemia has developed. Identifying proteinuria in absence of inflammation or significant haematuria would lead to measurement of a UPC ratio. Presence of pyuria with or without bacteruria would lead to a urine culture and sensitivity being performed. Identifying crystalluria or presence of casts might also lead to additional diagnostics being performed. Often the challenge can be just collecting the urine. For dogs, you might request that the pet owner drop off a first morning’s urine specimen in a clean or sterile container. For cats, the owner might bring a specimen from a clean litter box, or it may be more practical to simply palpate the bladder and isolate it for collection of a urine specimen by cystocentesis; ultrasound guidance should not be necessary.
Creatinine—SDMA increases earlier than creatinine in dogs and cats with CKD. SDMA increases on average with 40% loss of kidney function versus creatinine, which does not increase until 75% of kidney function is lost. In addition, creatinine is impacted by lean body mass, whereas SDMA is not. Therefore, SDMA is a more sensitive indicator of kidney function in animals with poor body condition.

BUN—BUN is also a late marker of kidney dysfunction in contrast to SDMA. In addition, BUN can be influenced by decreased production in liver disease and increases with high-protein meals or gastrointestinal bleeding versus SDMA, which changes only with alterations of the GFR.

Urine specific gravity—Natural fluctuations are normal and can be influenced by how much the animal drinks the day the urine is collected as well as the time of day of collection. Poor urine concentration is not specific to the kidney and can be influenced by other diseases like diabetes, liver disease, and Cushing’s disease versus SDMA, which is only influenced by changes in kidney function.

UPC—The urine protein:creatinine (UPC) ratio is a urine test. It is used to fully quantify protein detected in the urine once transient proteinuria, urinary tract infection, inflammation or significant haematuria has been ruled out. UPC may detect CKD earlier than creatinine if the primary target of the disease is the glomerulus and with some cases of tubulointerstitial disease. However, it is also common for the UPC to remain normal in animals with CKD, especially in early stages when SDMA may be increased. Persistent proteinuria that results in UPCs greater than 0.4 in cats and 0.5 in dogs, where prerenal and postrenal proteinuria have been ruled out, are consistent with glomerular or tubulointerstitial CKD, whereas UPCs greater than 2.0 are strongly suggestive of glomerular disease. In animals with proteinuria, UPC should be used to monitor progression and response to therapy.

Microalbuminuria—Microalbuminuria is a urine test. It is an early marker only in some cases of CKD. Physiologic transient increases are common. It will also be positive with urinary tract inflammation, so additional testing is needed to rule out urinary tract infection, inflammation, or significant haematuria. Once persistence has been established and false positives eliminated, microalbuminuria will be the earliest indicator of glomerular disease. In early glomerular disease when GFR may still be normal, SDMA may also remain normal. Similarly, microalbuminuria may be an early indicator of some but not all tubulointerstitial CKD, and as GFR decreases, SDMA will increase. A positive result should always be followed by a UPC test to determine quantitative value. It is common for the microalbuminuria test and UPC to be normal, especially in early CKD.
IDEXX SDMATM correlates with GFR and therefore will increase in acute kidney injury (AKI). Because it increases when there is on average 40% loss of GFR and as early as 25% kidney function loss versus creatinine, which is not increased until up to 75% loss of GFR, it will likely increase earlier in AKI. By the time an animal presents with clinical signs and is azotaemic, SDMA should be clearly increased. IDEXX SDMATM might add value to help confirm toxin exposure when suspected, e.g., a scenario of possible lily exposure where the cat is hospitalized and being serially monitored for evidence of kidney injury. Demonstrating an increase in SDMA would confirm altered GFR, likely because of acute injury from the toxic plant, justifying continued hospital care.
Urine changes consistent with kidney disease include but are not limited to:
Inappropriate urine concentration—USG less than 1.030 for dogs, USG less than 1.035 for cats.
Proteinuria—While small amounts of protein may normally be found in the urine, proteinuria can indicate both renal and nonrenal disease. If significant proteinuria is detected and there is an inactive sediment, a urine protein:creatinine (UPC) ratio should be performed for protein quantification for accurate assessment and monitoring.
Glucosuria (without hyperglycaemia)—Persistent renal glucosuria may suggest tubular injury from renal infection, as with pyelonephritis or leptospirosis, exposure to potential toxins (e.g., jerky treats or heavy metals), or less commonly congenital renal glucosuria. Active urine sediment—Presence of pyuria and bacteruria in a sterilely acquired specimen would be suggestive of urinary tract infection, and a urine culture and sensitivity should be performed. The significance of haematuria, crystals, and epithelial cells would depend on the method of urine collection and storage. Significance of casts depends on type of cast and number present.
SDMA is a serum test and a good marker of GFR; it increases as kidney function decreases, regardless of underlying cause. It is both sensitive and specific for loss of kidney function. Unlike SDMA, the microalbuminuria test and UPC are urine tests. They detect protein in the urine, which can be from anywhere in the urinary tract, so it’s important to eliminate false-positive results, especially with urinary tract infections, other inflammation, or significant haematuria. Transient increases that can also result from physiologic causes, such as strenuous exercise, fever, exposure to extreme cold or heat, and stress, must first be eliminated. Patients with glomerulopathy may develop proteinuria long before a significant change in GFR so their SDMA may remain normal until disease is more advanced and GFR decreases. However, patients with tubulointerstitial disease may have only mild proteinuria or no proteinuria at all; in these cases, SDMA will usually be an earlier indicator of CKD.
SDMA does not help localize kidney disease or the cause of kidney disease. It increases as GFR decreases, reflecting overall nephron function, regardless of lesion localization or aetiology.
CKD is common in older cats. Lean body mass decreases as cats age. IDEXX SDMATM is not impacted by lean muscle mass like creatinine is, which makes SDMA a more sensitive indicator of kidney function in older cats. Therefore, not only will IDEXX SDMATM help to detect CKD in older cats, it should be helpful to monitor kidney function in cats with CKD as their disease progresses and they continue to lose muscle mass.
SDMA correlates well with GFR, increasing when there is on average a 40% loss, and as little as 25% loss, of GFR. Reduced urine concentrating ability typically appears when there is, on average, a 67% loss of GFR, but this is variable. Cats with experimentally induced kidney disease, for example, showed poor correlation between maximum urine concentration and GFR, with some azotaemic cats retaining concentrating ability despite severe reduction in GFR. Given the lack of correlation between GFR and USG, a linear relationship between SDMA and USG could not be expected. SDMA will typically increase before isosthenuria associated with renal dysfunction develops. In many cases of early CKD, where SDMA is increased but creatinine is normal, the dog or cat will have an inappropriate USG (i.e., less than 1.030 for dogs or less than 1.035 for cats). However, in more than 25% of dogs and cats with an increased SDMA, significant urine concentrating ability will still remain because their GFR is only mildly decreased, or because of the variable timing of loss of concentrating ability.
Diagnostic imaging is suggested for motivated pet owners especially when urinary calculi, pyelonephritis, renal neoplasia or dysplasia, glomeronephritis, or other structural abnormalities are suspected. Radiography and abdominal sonography offer the most powerful combination to indicate kidney size and Back to home architecture.
NSAIDs, other potentially nephrotoxic drugs, and drugs primarily eliminated by renal excretion should be used cautiously in animals with altered kidney function. IDEXX SDMATM should be interpreted along with creatinine, urinalysis, and other findings to diagnose kidney disease, but SDMA will often be the earliest indicator of a decrease in kidney function in CKD. NSAIDs may be needed to sustain quality of life in some patients with CKD and should be used cautiously. NSAIDs should never be used in patients with acute kidney injury. Pet owners should be clearly and specifically educated about NSAIDs that are prescribed. If using NSAIDs in patients with CKD, ideally:
  • Use other pain management strategies first, to include opioids, weight loss, and nutraceuticals.
  • Use the least effective dose or use them intermittently.
  • Avoid other risk factors when NSAIDs are in use, such as general anaesthesia, salt restriction, diuretic use, dehydration, and others.
  • Select an NSAID with a low risk of gastrointestinal toxicity to avoid causing dehydration secondary to gastrointestinal disturbance.
  • Monitor for changes in liver activity and kidney function after initiating NSAID therapy and before and after each dose adjustment with blood testing and urinalysis
  • Discontinue NSAID use if toxicity is suspected or confirmed.