We are very excited to introduce Awanui Veterinary’s new immunoturbidometric assay for SDMA, an important advancement in assessing renal function in dogs and cats. Don’t miss out on our exclusive introductory offer – enjoy 10% off the regular price until the end of January! It’s now available to add to any biochemistry panel, so take advantage of this limited-time deal today!
Here’s a summary of the key points and how they might impact clinical practice:
Understanding SDMA and its benefits
What is SDMA?
SDMA (symmetric dimethylarginine) is a biomarker that indicates declining glomerular filtration rate (GFR). It’s more sensitive than serum creatinine in detecting early renal dysfunction. Unlike creatinine, SDMA is not reabsorbed by the renal tubules, and its levels are less influenced by factors such as muscle mass and diet.
Advantages over creatinine:
SDMA levels can rise before creatinine levels do, making it a useful early marker for kidney disease. Since SDMA is not affected by muscle mass, it can be more accurate in detecting renal issues in patients with varying muscle conditions.
Correlation with GFR:
There is a good correlation between SDMA, creatinine, and GFR. However, SDMA tends to increase before urine concentrating ability is lost, which might not be reflected by creatinine levels alone. However, its specificity can vary depending on the chosen cut-off values, which impacts how it is used in practice.
By understanding and using SDMA alongside other diagnostic tools, you can enhance early detection of renal issues and provide more effective care for your patients.
Interpretation of SDMA results
Reference intervals:
> Feline: 8 – 18 µg/dL
> Canine: 7 – 16 µg/dL
Note: The reference intervals for SDMA with Awanui’s assay are slightly higher compared to other reference laboratory assays due to the different methodologies used.
Special considerations:
> Younger animals and Greyhounds: These may have slightly increased reference intervals for SDMA.
> SDMA results should be evaluated alongside creatinine levels and a complete urinalysis for a comprehensive assessment of renal function (if not already requested, a creatinine test will be conducted on the same sample for interpretation purposes).
– High SDMA with normal creatinine: This can indicate early renal disease. It’s important to monitor trends over time and assess changes in urinalysis.
– Mismatch between SDMA and creatinine: A significant discrepancy (e.g., SDMA is 2-3 times the upper limit of the RI while creatinine is within RI) warrants further investigation. This could suggest other underlying conditions, such as neoplasia.
Recommended clinical approach
> Monitor trends: Single test results should not be used in isolation. Serial measurements and trends over time are crucial for diagnosing and managing renal disease.
> Integrate data: Always combine SDMA results with creatinine, urinalysis, and clinical findings for a holistic view of the patient’s renal health.
> Further diagnostics: In cases where SDMA levels are markedly elevated while creatinine levels remain normal, additional diagnostics may be needed to rule out or identify other conditions affecting renal function.
By understanding and using SDMA alongside other diagnostic tools, you can enhance early detection of renal issues and provide more effective care for your patients.
Sample requirements and pricing
– Serum or heparinised plasma (haemolysed and lipaemic samples are not suitable for testing).
– Results will be available within 2 working days.
– For promotional pricing, contact your local laboratory or check your email for the update.
References:
· Brans M et al., Plasma symmetric dimethylarginine and creatinine concentrations and glomerular filtration rate in cats with normal and decreased renal function. JVIM. 35:303-311, 2021.
· Coyne MJ et al The association between symmetric dimethylarginine concentrations and various neoplasms in dogs and cats. Vet Comp Oncol 20:846-853, 2022.
· Hokamp and Nabity., Renal biomarkers in domestic species. Vet Clin Pathol. 45:28-56, 2016 .
· Kopke MA et al. Variability of Symmetric Dimethylarginine in Apparently Healthy Dogs. J Vet Intern Med. 32:736–742, 2018.
· Liffman R et al. Establishment of reference intervals for serum symmetric dimethylarginine in adult nonracing Greyhounds. Vet Clin Pathol 47:458-463, 2018.
· McKenna M et al. Relationship between serum iohexol clearance serum SDMA concentration, and serum creatinine concentration in non-azotemic dogs. J Vet Intern Med. 34:186-194, 2020.
· Peterson ME et al. Evaluation of Serum Symmetric Dimethylarginine Concentration as a Marker for Masked Chronic Kidney Disease in Cats With Hyperthyroidism. JVIM. 32:295-304, 2018.
· Pelander L et al. Comparison of the diagnostic value of symmetric dimethylarginine, cystatin C, and creatinine for detection of decreased glomerular filtration rate in dogs. J Vet Intern Med. 33:630–639, 2019.
· Prieto JM et al. Biologic variation of symmetric dimethylarginine and creatinine in clinically healthy cats. Vet Clin Pathol. 49:401-406, 2020.
Yi KC et al. Effect of withholding food versus feeding on creatinine, symmetric dimethylarginine, cholesterol, triglycerides, and other biochemical analytes in 100 healthy dogs. J Vet Intern Med. 37:626–634, 2023