LOINCActiveBoth

LOINC Code 78006-4: GFR Isotopic based on 1.73 sq M (U+S/P) [Vol rate/Area]

78006-4 is a LOINC code used to identify GFR Isotopic based on 1.73 sq M (U+S/P) [Vol rate/Area] in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Glomerular filtration rate. It is commonly used with the system or sample type Urine+Ser/Plas.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Glomerular filtration rate. It is commonly used with the system or sample type Urine+Ser/Plas.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Both
  • Method: Isotopic based on 1.73 sq M

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

Isotopic Glomerular filtration rate/1.73 sq M [Volume Rate/Area] in Urine and Serum or Plasma
Glomerular filtration rate
This test measures kidney filtration after injection of a radioactive tracer (e.g. technetium 99m DTPA). It is an actual measurement of glomerular filtration rate (GFR). The test is a several hour long kidney function test typically performed to accurately verify the level of renal dysfunction. It requires sequential collection of both blood and urine specimens after the tracer injection. Isotopic GFR may be used for monitoring renal function over time, or in chronic renal failure patients approaching dialysis. [PMID1391702] The submitter's lab uses the following formula to determine GFR: GFR = (UV/P) x (1.73/BSA) Where, for each timed urine collection, U = (urine collection CPM = UbkgCPM) V = urine flow rate: (urine volume / elapsed time) in units of mL/min P = (average serum or plasma CPM = Bbkg CPM) The average serum CPM (counts per minute) will be the average of Bo and B1 for the first urine collection (U1) and the average of B1 and B2 for the second collection (U2). Average the calculated GFR results for the two collection periods to obtain the final GFR result.
Chemistry; GFR; Glom; Kidney; Nephrology; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; Renal; SerP; SerPl; SerPlas; Serum; Serum or plasma; Square Meter; SR; UA; UR; Ur+SerPl; Urn; Volume rate/area; Volume Rate/Ratio

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

GFR Isotopic based on 1.73 sq M (U+S/P) [Vol rate/Area]Isotopic Glomerular filtration rate/1.73 sq M [Volume Rate/Area] in Urine and Serum or PlasmaIsotopic GFR/1.73 sq M Ur+SerPl-ArVRatGlomerular filtration rateCHEMGFR, Urine+BloodArVRat

Frequently asked questions

Code details

Code78006-4
SystemLOINC
Display nameGFR Isotopic based on 1.73 sq M (U+S/P) [Vol rate/Area]
DescriptionGlomerular filtration rate
Short nameIsotopic GFR/1.73 sq M Ur+SerPl-ArVRat
ComponentGlomerular filtration rate
PropertyArVRat
TimingPt
System (specimen)Urine+Ser/Plas
ScaleQn
MethodIsotopic based on 1.73 sq M
ClassCHEM
Example unitsmL/min/1.73 sq m
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.52
Last changed2.79

Consumer names

GFR, Urine+Blood

Part names

Glomerular filtration rateArVRatPtUrine+Ser/PlasQnIsotopic based on 1.73 sq MVolume Rate/AreaPoint in time (spot)Urine and Serum or Plasma

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.