Speeckaert · Journal of personalized medicine 2021 · narrative review · n=?

Measured Glomerular Filtration Rate: The Query for a Workable Golden Standard Technique.

Cited 35 times in the scientific literature.

Level 5 - mechanism / opinion, no new human data

Narrative review with expert commentary and no original data or systematic review methodology.

PubMed 34683089 · doi:10.3390/jpm11100949 · record verified 2026-08-29

What was done

The authors reviewed the methodological, analytical, and practical challenges of measured glomerular filtration rate (mGFR) techniques, evaluating classical inulin clearance alongside radioactive (51Cr-EDTA, 99mTc-DTPA, 125I-iothalamate) and non-radioactive (iohexol, iothalamate) exogenous markers.

What was found

No quantitative data or numerical outcomes were reported in the abstract. The authors highlighted that radioactive markers have supply constraints and safety requirements, while non-radioactive markers lack certified reference materials and evidence-based procedural standardization (such as urinary versus plasma clearance, single versus multiple sampling protocols, and delay timing), leading to substantial inter-study variability.

Why it matters

Standardization of mGFR markers, measurement assays, and sampling protocols is necessary before alternative clearance methods can serve as true reference standards or be used to reliably validate new endogenous filtration markers.

Limits

This is a narrative review providing expert perspective rather than empirical data or a systematic meta-analysis. The abstract reports no quantitative comparisons, effect estimates, or diagnostic accuracy metrics across the reviewed markers.

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