Monoclonal Protein Quantitation, Random, Urine

Clinical Use

Use

This test is useful for identifying monoclonal gammopathies by analyzing proteins in a random urine specimen. It characterizes urine protein fractions—including albumin, alpha‑1, alpha‑2, beta and gamma globulins—and quantifies monoclonal proteins (‘M spike’). It aids in diagnosing conditions such as multiple myeloma, primary systemic amyloidosis, light‑chain deposition disease, MGUS, and idiopathic Bence Jones proteinuria. Light chains or heavy‑chain fragments in the urine may indicate renal injury (e.g., Fanconi syndrome), deposition disease, or renal insufficiency.([mayocliniclabs.com](https://www.mayocliniclabs.com/test-catalog/Overview/616909?utm_source=openai))

Special Instructions

Not provided.

Limitations

Random urine is sufficient for detection but 24‑hour urine is preferred for quantitation and monitoring. Urine specimens may be rejected if unsuitable; all are evaluated for suitability. Hemolysis can cause spurious electrophoretic bands; radiographic agents and penicillin may interfere. Monoclonal gammopathies are rarely seen in patients younger than 30. A normal protein electrophoretic pattern does not exclude monoclonal gammopathy—M‑protein isotyping may be needed.([mayocliniclabs.com](https://www.mayocliniclabs.com/test-catalog/Overview/616909?utm_source=openai))

Test Details

Methodology

Immunoassay (Multiplex Protein Panel)

Biomarkers

4 components

Total Protein (Turbidimetry/Enzymatic Colorimetric Assay) • OtherProtein Electrophoresis (Agarose Gel Electrophoresis) • Multiplex Protein PanelProtein/Creatinine Ratio (Enzymatic Colorimetric Assay) • OtherM‑protein Mass‑Fix (MALDI‑TOF MS) • Other