likes2watchU
Literotica Guru
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I have not had time to fact check all of this, but the references for the listed information are included.There are new studies saying that the gfr is not as accurate for diagnosing renal failure as previously thought.... I haven't looked in to it but I will
Here are the current recommendations when eGFR (using serum creatinine alone) isn’t reliable for diagnosing or staging renal impairment:
Recommended Tests for Accurate Kidney Function Assessment (Beyond Traditional eGFR)
- Measured GFR (mGFR) using exogenous markers
- Inulin clearance is the gold standard for measuring GFR but is expensive and rarely used in routine practice.
Approximate cost: $600 per test. - Iohexol or iothalamate clearance are reliable alternatives and less invasive.
Approximate cost: $40–$600 depending on the method and region.
- Serum cystatin C-based eGFR (eGFRcys)
- Cystatin C is a protein filtered by the kidneys and is less influenced by age, muscle mass, sex, race, and diet compared to creatinine.
Approximate cost: $5–$10 for the reagent; commercial lab prices range from $99 to $205.
- Combined creatinine + cystatin C-based eGFR (eGFRcr-cys)
- This method combines both creatinine and cystatin C to improve accuracy.
Recommended when eGFR from creatinine alone is borderline or unclear.
Approximate cost: $200–$210.
- Urine albumin-to-creatinine ratio (uACR)
- While not a GFR test, uACR is essential to assess kidney damage and is used in combination with GFR to stage chronic kidney disease.
Approximate cost: $30–$80.
- Additional evaluations (based on clinical need)
- May include urinalysis, renal ultrasound, nuclear medicine scans (e.g., DTPA), or kidney biopsy.
Approximate cost varies widely: $50 for urinalysis to several thousand dollars for imaging or biopsy.
References:
- National Kidney Foundation & American Society of Nephrology Joint Statement on eGFR:
https://www.kidney.org/recommendati...ace-free-egfr-calculation-guidelines-clinical - NIH NIDDK article on alternatives to race-based kidney function calculations:
https://www.niddk.nih.gov/news/archive/2024/alternatives-race-based-kidney-function-calculations - Nature Reviews Nephrology article on limitations of eGFR:
https://www.nature.com/articles/s41581-019-0213-9 - Lab test pricing examples:
https://www.findlabtest.com/lab-test/kidney-function-test/cystatin-c-labcorp-121251
https://www.grassrootslabs.com/product/Cystatin_C_with_Glomerular_Filtration_Rate_Estimated_eGFR - Wikipedia overview of GFR and testing methods:
https://en.wikipedia.org/wiki/Glomerular_filtration_rate
https://en.wikipedia.org/wiki/Assessment_of_kidney_function