Learn about our test:
What is kidneyintelX.dkd™?
Our FDA-authorized test, kidneyintelX.dkd, employs our proprietary bioprognostic™ methodology. It combines blood-based biomarkers, which are closely correlated with subclinical inflammation and kidney tubular injury, with clinical data inputs from a patient’s medical record (UACR, HbA1c, BUN) to generate a patient-specific risk result that indicates whether an adult patient with type 2 diabetes and early-stage chronic kidney disease is at low, moderate, or high risk of progressive decline in kidney function, in the next 5 years.
What is the indicated use for the kidneyintelX.dkd test?
The kidneyintelX.dkd is for in-vitro diagnostic use for the determination of a kidneyintelX.dkd Level using an algorithm to combine clinical variables (blood urea nitrogen (BUN), hemoglobin A1c (HbA1c) and urine albumin creatinine ratio (UACR)) and the quantitative measurements of tumor necrosis factor receptor-1 (TNFR-1), tumor necrosis factor receptor-2 (TNFR-2) and kidney injury molecule-1 (KIM-1) in human plasma employing a MesoSector S 600 electrochemiluminescence immunoassay.
It is indicated for use as an aid in assessment of the risk of progressive decline in kidney function (sustained decrease in eGFR greater than or equal to 40% lasting more than 3 months) within a period of up to 5 years following kidneyintelX.dkd Level measurement in adult patients with type 2 diabetes and existing chronic kidney disease (defined for the purposes of this device as patients with an estimated glomerular filtration rate of 30-59 ml/min/1.73 m² or eGFR ≥ 60 ml/min/1.73 m² with albuminuria (UACR ≥ 30 mg/g)).
kidneyintelX.dkd is not intended for screening or as a stand-alone diagnostic test.
What specific prognostic biomarkers are being used for kidneyintelX.dkd testing?
The kidneyintelX.dkd test incorporates inputs from three (3) well studied biomarkers from human plasma:
- TNFR-1: soluble Tumor Necrosis Factor Receptor-1
- TNFR-2: soluble Tumor Necrosis Factor Receptor-2
- KIM-1: Kidney Injury Molecule-1
The three biomarkers are measured using an electrochemiluminescence immunoassay on a Mesoscale Sector S 600 instrument.
What clinical data points are included for kidneyintelX.dkd testing?
We also incorporate the values of the following clinically relevant data inputs:
- UACR
- HbA1c
- BUN
How is progression of kidney disease defined?
Progressive decline in kidney function is defined as a sustained decrease in eGFR ≥ 40% within a period of up to 5 years following kidneyintelX.dkd measurement. For study analysis, sustained decrease was confirmed with a second eGFR value showing > 40% decline at least 3 months after the first observed drop of 40%.
What is the benefit of ordering a kidneyintelX.dkd test if my patient’s CKD is under control?
Through insights provided by the kidneyintelX.dkd result, clinicians will be able to assess which patients are at low, moderate, or high risk for progressive decline in kidney function, and therefore, can more appropriately target resources, and guideline-recommended cardio- and reno-protective treatments to advance kidney health.
The test results are not intended to diagnose any disease or condition. The test results are intended to be used in conjunction with other clinical and diagnostic findings, consistent with professional standards of practice, including information obtained by alternative methods, and clinical evaluation, as appropriate.
Is there an age range?
The kidneyintelX.dkd test is indicated for use in adult patients 21 years of age and older.
Can I use this test on non-diabetics?
No. The kidneyintelX.dkd test is an aid to further assess the risk of progressive decline in kidney function for adult patients with type 2 diabetes and early-stage chronic kidney disease.
How will kidneyintelX.dkd benefit my practice and my patients?
After adult patients with type 2 diabetes are screened for kidney disease, you will still need to identify which patients with chronic kidney disease need lower-level maintenance, ongoing monitoring, or immediate lifestyle and therapeutic adjustments and referrals to a specialist.
The kidneyintelX.dkd yields a simple-to-understand result – low, moderate, high — stratifying adult diabetic patients with chronic kidney disease in stages 1-3b for their individual risk for progressive decline in kidney function over the next five years.
With one simple blood test, you will receive your patient’s risk result which will help as you consider clinical guideline recommendations for management of DKD. The test results are intended to be used in conjunction with other clinical and diagnostic findings, consistent with professional standards of practice, including information obtained by alternative methods, and clinical evaluation, as appropriate.
Why is kidneyintelX.dkd a more advanced measure for risk of CKD progression in adult type 2 diabetes patients vs. UACR or eGFR alone?
Existing measurements don’t adequately and precisely predict disease progression for several reasons.
- There are issues with albuminuria.
- Biological variability
The measurement of albuminuria can be imprecise due to technical factors (e.g., time of day) or true normal biological variability. For example, studies indicate that two UACR values in the same patient – just a few weeks apart – vary significantly, such that an increase by 124% or a decrease by 55% from the prior reading can be within the normal range of variability without indicating true clinically significant changes.1 - Assay variability
The assays for albuminuria are not standardized nationally. Therefore, there can be differences based on the testing platform and/or clinical lab. - Regression of albuminuria over time
Some patients will experience spontaneous regression of albuminuria. - Progression without albuminuria
Data indicates that 20-30% of patients with DKD who experience progression never develop albuminuria.
- Biological variability
- There are issues with eGFR.
- eGFR is an “estimate.”
- Therefore, it may be discordant with true “measured” GFR (mGFR; usually done only in research settings) by > 30% in a significant fraction of patients.
- Data indicates that 33-50% of patients have different CKD stages based on eGFR vs. mGFR.
- Regression/improvement of eGFR spontaneously
- Data from large database studies indicate that a sizable fraction of patients (roughly equal to the proportion that experience progression) with CKD experience improvement in kidney function over time. While this is contrary to the typical notion that once CKD is present it does not improve, these data points highlight the uncertainty and issues with using eGFR as a primary tool for prediction of progression. (See figure below.)
- eGFR is an “estimate.”
- And then, there’s hyperfiltration.
- Hyperfiltration plays a critical role in chronic kidney disease in diabetes as it puts stress on the filtration barrier and post-filtration mechanisms.
- The increased flow increases the delivery and reabsorption of small and large molecular weight solutes resulting in injury to the kidneys.
- Despite significant damage to some of the kidney’s tissue, the remaining nephrons initially try to compensate, trying to preserve kidney function.
1 Waikar SS, et al. Am J Kidney Dis. 2018. 72(4): 538-546. doi: 10.1053/j.ajkd.2018.04.023
How will I get the results?
You can expect to receive the kidneyintelX.dkd test report in approximately 5-7 days.
How should I interpret the kidneyintelX.dkd result?
LOW: what does a low test result mean?
In the clinical performance study, the estimated probability of progressive decline of kidney function over 5 years was 6% in patients with ‘Low’ kidneyintelX.dkd levels.
MODERATE: what does a moderate test result mean?
In the clinical performance study, the estimated probability of progressive decline of kidney function over 5 years was 22% in patients with ‘Moderate’ kidneyintelX.dkd levels.
HIGH: what does a high test result mean?
In the clinical performance study*, the estimated probability of progressive decline of kidney function over 5 years was 67% in patients with ‘High’ kidneyintelX.dkd levels.
When should I retest my patient?
Currently, the kidneyintelX.dkd test is not intended for serial monitoring of kidney disease progression.
Is kidneyintelX.dkd result limited by race like eGFR?
No. The kidneyintelX.dkd test does not use race as an input to the machine-learning algorithm.
Should chronic kidney disease (CKD) patients already on a SGLT2i be tested with kidneyintelX.dkd?
Yes. The KDIGO and ADA guidelines recommend use of SGLT2i medications for kidney protection and it is appropriate to test patients who are already taking these medications with kidneyintelX.dkd.
This device, however, is not intended for diagnosis of any disease, for serial monitoring of kidney disease progression, or for monitoring the effect of any therapeutic product.
Can my patient’s eGFR decrease after I start them on an SGLT2i?
Studies have shown that an immediate decline in eGFR (>10%) can be expected after initiation of an SGLT2i in up to 30% of patients and may be attributed to a hemodynamic effect on intraglomerular pressures. Clinical studies have also shown that, on average, eGFR in the treatment group will cross-over the eGFR in the placebo group at around 12 months after initiation of treatment, with a slower rate of decline vs. placebo over time.2
2 Chauhan, K. et al. Initial Validation of a Machine Learning-Derived Prognostic Test (KidneyIntelX) Integrating Biomarkers and Electronic Health Record Data to Predict Longitudinal Kidney Outcomes. Kidney360 1, 731-739, doi:10.34067/kid.0002252020 (2020).
Why are patients on Enbrel® contraindicated for kidneyintelX.dkd?
Enbrel interferes with the ability to accurately measure TNFR-2 in patient specimens and is contra-indicated for patients when ordering kidneyintelX.dkd testing.
Are there other substances that could interfere with generating a kidneyintelX.dkd result?
Yes. Our analytical validation studies show that blood specimens with selenium levels above 226 ng/mL may falsely elevate biomarker results.
The kidneyintelX.dkd test should not be used in patients with known elevation of total protein above 8.5 g/dL or known elevation of rheumatoid factor above 665 IU/mL.
The full list of substances evaluated in our analytical validation is provided in the Product Technical Sheet.
Are there limitations that I should know about the kidneyintelX.dkd test?
Yes. A list of limitations about the test is provided in the Product Technical Sheet.
Who do I contact if I have questions?
If you have questions about the kidneyintelX.dkd results, please email medicalaffairs@renalytix.com.
If you have questions about billing, please contact the client success team at 888-203-2725 or email billing@renalytix.com.