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Test ID: MPSU Monoclonal Protein Study, 24 Hour, Urine

Reporting Name

Monoclonal Protein Study, 24 Hr, U

Useful For

Monitoring patients with monoclonal gammopathies using 24-hour urine specimens

Clinical Information

Urine proteins can be grouped into 5 fractions by protein electrophoresis:







The urine total protein concentration, the electrophoretic pattern, and the presence of a monoclonal immunoglobulin light chain may be characteristic of monoclonal gammopathies such as multiple myeloma, primary systemic amyloidosis, and light chain deposition disease.


The following algorithms are available:

-Amyloidosis: Laboratory Approach to Diagnosis

-Multiple Myeloma: Laboratory Screening


A characteristic monoclonal band (M-spike) is often found in the urine of patients with monoclonal gammopathies. The initial identification of an M-spike or an area of restricted migration is followed by immunofixation to identify the immunoglobulin heavy chain and/or light chain.


Immunoglobulin free light chains as well as heavy chain fragments may be seen in the urine of patients with monoclonal gammopathies. The presence of a monoclonal light chain M-spike of greater than 1 g/24 hours is consistent with a diagnosis of multiple myeloma or macroglobulinemia.


The presence of a small amount of monoclonal light chain and proteinuria (total protein >3 g/24 hours) that is predominantly albumin is consistent with primary systemic amyloidosis (AL) or light chain deposition disease (LCDD).


Because patients with AL or LCDD may have elevated urinary protein without an identifiable M-spike, urine protein electrophoresis is not considered an adequate screen for these disorders and immunofixation is also recommended.

Profile Information

Test ID Reporting Name Available Separately Always Performed
PTU Protein, Total, 24 HR, U Yes Yes
PEU Protein Electrophoresis, 24 Hr, U No Yes
IFXU Immunofixation, 24 Hr, U No Yes

Testing Algorithm

The following algorithms are available:

-Amyloidosis: Laboratory Approach to Diagnosis

-Multiple Myeloma: Laboratory Screening

Report Available

4 to 6 days

Day(s) Performed

Protein, total: Monday through Sunday

Electrophoresis, protein; Immunofixation: Monday through Friday

Clinical Reference

1. Kyle RA, Katzmann JA, Lust JA, Dispenzieri A: Clinical indications and applications of electrophoresis and immunofixation. In: Rose NR, Hamilton RG, Detrick B, eds. Manual of Clinical Laboratory Immunology. 6th ed. ASM Press; 2002:71-91

2. Keren DF, Humphrey RL: Clinical indications and applications of serum and urine protein electrophoresis. In: Detrick BD, Hamilton RG, Schmitz JL eds. Manual of Molecular and Clinical Laboratory Immunology. 8th ed. 2016:chap 8

Method Name

PTU: Turbidimetry

PEU: Agarose Gel Electrophoresis

IFXU: Immunofixation

Specimen Type


Shipping Instructions

Refrigerate specimen during collection and send refrigerated.

Necessary Information

24-Hour volume is required.

Specimen Required


-Urine Container, 60 mL (T313)

-Sarstedt 5 mL Aliquot Tube (T914)

Submission Container/Tube: Plastic, 60-mL urine bottle and plastic, 5-mL tube

Specimen Volume: 50 mL

Collection Instructions:

1. Collect urine for 24 hours.

2. Aliquot at least 25-mL specimen in plastic, 60-mL urine bottle and at least 1-mL of specimen in plastic, 5-mL tube.

3. Label specimens appropriately (60-mL bottle for protein electrophoresis and 5-mL tube for protein, total).

Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.

Specimen Minimum Volume

25 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Urine Refrigerated (preferred) 14 days
  Frozen  5 days
  Ambient  24 hours

Reference Values


<229 mg/24 hours

Reference values have not been established for patients <18 years of age.

Reference value applies to 24-hour collection.



The following fractions, if present, will be reported as mg/24 hours:


Alpha-1 globulin

Alpha-2 globulin


Gamma globulin

Test Classification

This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information




LOINC Code Information

Test ID Test Order Name Order LOINC Value
MPSU Monoclonal Protein Study, 24 Hr, U In Process


Result ID Test Result Name Result LOINC Value
82025 Immunofixation, 24 Hr, U 33042-3
607970 Albumin 6941-9
TP2 Total Protein, 24 HR, U 2889-4
TM23 Collection Duration 13362-9
607971 Alpha-1 globulin 6794-2
606980 Immunofixation Flag, 24 Hr, U No LOINC Needed
607972 Alpha-2 globulin 6795-9
VL21 Urine Volume 19153-6
607973 Beta globulin 94714-3
607974 Gamma globulin 94715-0
2833 A/G Ratio 44294-7
21446 M spike 42482-0
22307 M spike 42482-0
21447 Impression 32210-7

Urine Preservative Collection Options

Note: The addition of preservative or application of temperature controls must occur within 4 hours of completion of the collection.







50% Acetic Acid


Boric Acid


Diazolidinyl Urea


6M Hydrochloric Acid


6M Nitric Acid


Sodium Carbonate








If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.

Mayo Clinic Laboratories | Neurology Catalog Additional Information:

mml-Movement-Disorders, mml-Demyelinating-Diseases, mml-Neuroimmunology, mml-Neuromuscular, mml-Autonomic, mml-Neuro-oncology, mml-Pediatric, mml-Pain, mml-Spinal-Cord