🦴 TmP/GFR (Renal Phosphate Threshold)
UseWhen to use: hypophosphatemia workup for renal phosphate wasting.
StrataLow TmP/GFR with low Pp → renal wasting cue.
LimitsWhen not to use: non-steady phosphate / AKI extremes. · Pitfall: mixing mg/dL and mmol/L. · FGF23 labs may follow.
SourceBijvoet–Kenny TmP/GFR method
This-shift next steps
After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.
Paste the link in Slack, Teams, X, or LinkedIn — the preview image comes from this page’s Open Graph card.
Methodology · worked example, guidelines & full notes
TRP → TmP/GFR.
When to use
When to use: hypophosphatemia workup for renal phosphate wasting.
How it works
TRP then Kenny–Glen TmP/GFR from Pp, Up, PCr, UCr.
Key points
- TRP → TmP/GFR.
- Unit-consistent.
- Next: FGF23 / PTH.
References
- Bijvoet–Kenny TmP/GFR method
Worked calculation
The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.
| Phosphate units | mg/dL |
|---|---|
| Plasma phosphate (Pp) | 2.5 mg/dL or mmol/L |
| Urine phosphate (Up) | 40 same as Pp |
| Plasma creatinine | 1.0 mg/dL |
| Urine creatinine | 100 mg/dL |
→TmP/GFR2.10mg/dL
- TRP：84.0%
- Cue：<2.5 mg/dL — low threshold band (renal phosphate wasting cue)
Verification & sources · governance
FAQ
Frequently asked questions
- Does TmP/GFR (Renal Phosphate Threshold) upload patient data? Where is it calculated?
- Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
- How is TmP/GFR (Renal Phosphate Threshold) calculated in practice? Can you show a worked example?
- Inputs: Phosphate units mg/dL, Plasma phosphate (Pp) 2.5 mg/dL or mmol/L, Urine phosphate (Up) 40 same as Pp, Plasma creatinine 1.0 mg/dL, Urine creatinine 100 mg/dL → Result: TmP/GFR 2.10 mg/dL（TRP: 84.0%, Cue: <2.5 mg/dL — low threshold band (renal phosphate wasting cue)）