Test Code SMPU Monoclonal Protein Screen, 24 Hour, Urine
Shipping Instructions
Refrigerate specimen during collection and send refrigerated.
Necessary Information
24-Hour volume (in milliliters) is required.
Specimen Required
Supplies: Urine Container, 60 mL (T313)
Submission Container/Tube: Plastic, 60-mL urine bottle
Specimen Volume: 50 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. Aliquot between 30 mL and 50 mL of urine into a plastic, 60-mL urine bottle.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Useful For
Monitoring patients with monoclonal gammopathies
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
MPTU | M-protein Mass-Fix, 24 HR, U | No | Yes |
PTU3 | Protein, Total, 24 HR, U | Yes | Yes |
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
PEU | Protein Electrophoresis, 24 Hr, U | No | No |
Testing Algorithm
Testing for urine monoclonal proteins (M-proteins) with mass-fix alone is not considered adequate screening for monoclonal gammopathies.
The laboratory will evaluate the urine for M-proteins using the mass-fix method, and if positive for M-protein, protein electrophoresis will be performed at an additional charge.
The following algorithms are available:
Special Instructions
Method Name
PTU3: Turbidimetry
PEU: Agarose Gel Electrophoresis
MPTU: Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS)
Reporting Name
M-protein Screen, 24 HR, USpecimen Type
UrineSpecimen Minimum Volume
30 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 14 days | |
Frozen | 5 days | ||
Ambient | 24 hours |
Reference Values
PROTEIN, TOTAL
<229 mg/24 hours
Reference values have not been established for patients younger than 18 years of age.
ELECTROPHORESIS, PROTEIN
The following fractions, if present, will be reported as mg/24 hours:
Albumin
Alpha-1-globulin
Alpha-2-globulin
Beta-globulin
Gamma-globulin
MASS-FIX M-PROTEIN ISOTYPE
M-protein Isotype MS:
No monoclonal protein detected
Flag M-protein Isotype MS:
Negative
Interpretation
The presence of a monoclonal immunoglobulin light chain in the urine is seen in multiple myeloma, macroglobulinemia, primary systemic amyloidosis and light-chain deposition disease, monoclonal gammopathy of undetermined significance, and idiopathic Bence-Jones proteinuria. The presence of a monoclonal light chain can produce renal insufficiency, may be deposited as amyloid fibrils, may damage the proximal tubes producing Fanconi syndrome, or light chains may deposit in the glomerulus and cause light-chain deposition disease.
Heavy-chain fragments as well as light chains may be seen in the urine of patients with multiple myeloma or amyloidosis.
Clinical Reference
1. Abraham RS, Barnidge DR: Protein analysis in the clinical immunology laboratory. In: Detrick BD, Hamilton RG, Schmitz JL eds. Manual of Molecular and Clinical Laboratory Immunology. 8th ed. 2016:chap 4
2. Sykes E, Posey Y: Immunochemical characterization of immunoglobulins in serum, urine, and cerebrospinal fluid. In: Detrick B, Hamilton RG, Schmitz JL, eds. Molecular and Clinical Laboratory Immunology. 8th ed. Wiley; 2016:chap 9
Day(s) Performed
Monday through Friday
Report Available
4 to 6 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest 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
84156
84166 Electrophoresis, protein (if appropriate)
0077U
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SMPU | M-protein Screen, 24 HR, U | In Process |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
617117 | M-protein Isotype MS, 24 HR, U | In Process |
TP6 | Total Protein, 24 HR, U | 2889-4 |
TM24 | Collection Duration | 13362-9 |
617118 | Flag M-protein Isotype MS, 24 HR, U | No LOINC Needed |
VL92 | Urine Volume | 3167-4 |
Forms
If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.