Interpreting your SDMA results

IDEXX SDMA algorithm

An elevated SDMA* concentration is a reflection of impaired glomerular filtration rate (GFR). Both primary kidney disease and secondary kidney insults, such as concurrent disease, can cause an elevation in SDMA concentration. Follow this algorithm to investigate elevated SDMA concentrations and determine whether acute, active, or chronic injury is occurring. Also use the algorithm to follow up an increased SDMA with further investigation, management, and monitoring with the IMM protocol.

Initial steps in investigating, managing, and monitoring impaired GFR as identified by an elevated SDMA


Underlying cause, treatable condition, concurrent disease, chronic kidney disease (CKD)

Underlying cause
  • Urinary tract infection (UTI)/pyelonephritis
  • Toxicity (e.g., NSAIDs, ethylene glycol, lilies)
  • Acute kidney Injury
  • Systemic hypertension
  • Chronic kidney disease (CKD)
Consider performing
  • Urine culture and minimum inhibitory concentration (MIC) susceptibility
  • Infectious disease testing
  • Abdominal imaging
  • Urine protein:creatine (UPC) ratio (proteinuria)
  • Blood pressure 
Concurrent condition to assess
  • Hydration status
  • Thyroid status (feline) 


Treat underlying disease, manage assessed kidney injury, adjust care protocols

Treat appropriately
  • Underlying disease (e.g., pyelonephritis, infectious disease)
  • Dehydration
  • Discontinue nephrotoxic medications (e.g., NSAIDs)
  • Hypertension
  • Proteinuria
Additional support
  • Ample, clean water
  • Kidney-supportive diet if warranted
Adjust anesthesia protocols
  • Provide fluids (intravenous or subcutaneous)
  • Oxygen support prior to, during, and after procedure
  • Adjust pain management


Manage and monitor outcomes

Monitor renal biomarkers

Trended testing of the following:

  • SDMA, BUN, creatinine, and phosphorus
  • Urinalysis
  • Blood pressure

GFR impairment, stable

SDMA remains increased, but stable
  • GFR remains impaired but stable
  • Consider CKD diagnosis, refer to IRIS staging and treatment guidelines
  • Institute appropriate supportive care and monitoring

GFR impairment, progressive

SDMA continues to increase
  • Ongoing active kidney injury
  • Revisit investigate: repeat or additional diagnostics
  • Institute ongoing supportive care

GFR restoration

SDMA returns to normal
  • Recovery from mild injury
  • Response to appropriate therapy
  • Compensatory mechanisms
  • Recheck within 6 months–1 year

Get printable versions of the algorithm and protocol

IDEXX SDMA algorithm and IMM protocol

*Symmetric dimethylarginine.

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The information contained herein is intended to provide general guidance only. As with any diagnosis or treatment, you should use clinical discretion with each patient based on a complete evaluation of the patient, including history, physical presentation, and complete laboratory data. With respect to any drug therapy or monitoring program, you should refer to product inserts for a complete description of dosages, indications, interactions, and cautions. Diagnosis and treatment decisions are the ultimate responsibility of the primary care veterinarian.