Sign in →

Test Code STRC Standard Renal Clearance, Plasma and Random Urine


Specimen Required


Contact MLI for approval prior to ordering this test.

 

Both plasma and urine are required.

 

Specimen Type: Plasma

Container/Tube: 6-mL Green top (sodium heparin)

Specimen Volume: 3-4 mL

Collection Instructions: Label specimen as plasma.

 

Specimen Type: Urine

Container/Tube: Sarstedt 5 mL Aliquot Tube (T914)

Specimen Volume: 5 mL

Collection Instructions:

1. Collect a random urine collection.

2. No preservative.

3. Label specimen as urine.


Useful For

Precise measurement of glomerular filtration rate and renal plasma flow

Profile Information

Test ID Reporting Name Available Separately Always Performed
IOTC Iothalamate Clearance No Yes
PAHCC PAH Clearance No Yes

Method Name

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Reporting Name

Standard Renal Clearance

Specimen Type

Plasma Na Heparin
Urine

Specimen Minimum Volume

2 mL plasma/5 mL urine

Specimen Stability Information

Specimen Type Temperature Time Special Container
Plasma Na Heparin Refrigerated (preferred) 7 days
  Frozen  7 days
Urine Refrigerated (preferred) 7 days
  Frozen  7 days

Reject Due To

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Reference Values

GLOMERULAR FILTRATION RATE

20 years: 87-141 mL/min/SA

(Iothalmate) Decreases by 4.95 mL/min/decade

 

≤ 19 years: Not established

20 years: 87-141

21 years: 86-140

22 years: 86-140

23 years: 85-139

24 years: 85-139

25 years: 84-138

26 years: 84-138

27 years: 83-137

28 years: 83-137

29 years: 82-136

30 years: 81-136

31 years: 81-136

32 years: 81-135

33 years: 80-135

34 years: 80-134

35 years: 79-134

36 years: 79-133

37 years: 78-133

38 years: 78-132

39 years: 77-132

40 years: 77-131

41 years: 76-131

42 years: 76-130

43 years: 75-130

44 years: 75-129

45 years: 74-129

46 years: 74-128

47 years: 73-128

48 years: 73-127

49 years: 72-127

50 years: 72-126

51 years: 72-126

52 years: 71-125

53 years: 71-125

54 years: 70-124

55 years: 70-124

56 years: 69-123

57 years: 69-123

58 years: 68-122

59 years: 68-122

60 years: 67-121

61 years: 67-121

62 years: 66-120

63 years: 66-120

64 years: 65-119

65 years: 65-119

66 years: 65-119

67 years: 64-118

68 years: 64-118

69 years: 63-117

70-150 years: 62-116

 

PARA-AMINOHIPPURATE (PAH) CLEARANCE

PAH Clearance

0-19 years: not established

20-29 years: >448 mL/min/SA

30-39 years: >413 mL/min/SA

40-49 years: >378 mL/min/SA

50-59 years: >343 mL/min/SA

60-69 years: >308 mL/min/SA

70-79 years: >273 mL/min/SA

80-89 years: >238 mL/min/SA

90-99 years: >203 mL/min/SA

 

Note: Reference range decreases by 35mL/decade.

 

FILTRATION FRACTION

>or=16 years: 18-22%

Interpretation

Iothalamate Clearance:

Low glomerular filtration rate (GFR) values indicate abnormal renal function, which may be either reversible/transient or irreversible/permanent. GFR tends to decline with age.

 

Para-Aminohippurate (PAH) Clearance:

The renal clearance of PAH, calculated from measurements of PAH in serum and timed urine specimens, equals renal plasma flow (RPF). However, it is important to note that only 85% to 90% of PAH is cleared from the circulation in a single pass, so the PAH clearance may underestimate RPF by 10% to 15%.

 

Filtration Fraction (FF):

The FF is the fraction of plasma perfusing the kidneys that is filtered (FF=GFR/RPF). Under normal conditions, FF is approximately 20%. Values significantly different from this provide an index to changes in GFR relative to RPF. For example, in states of decreased renal perfusion due to congestive heart failure, both RPF and GFR are decreased, whereas the FF is >20%. 

Day(s) Performed

Monday through Friday

Report Available

Same day/1 to 4 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information

82542 x 7

LOINC Code Information

Test ID Test Order Name Order LOINC Value
STRC Standard Renal Clearance 96403-1

 

Result ID Test Result Name Result LOINC Value
IOTC Iothalamate Clearance 90995-2
PAHC PAH Clearance 96404-9
FILT Filtration Fraction 96405-6
CMT13 Comment 77202-0