Serum and plasma beta2 microglobulin values have emerged as markers for the activation of the cellular immune system, as well as a tumor marker
in certain hematologic malignancies. Urine beta2 microglobulin values indicate renal filtration disorders. Measurement of values in both serum
and urine can help distinguish a problem of cellular activation from a renal disorder.

The reference range of beta2 microglobulin in urine samples is 0-0.3 µg/mL. In serum or plasma samples, the reference range is 0-3 µg/mL.

It is recommended that each laboratory establish its own normal and pathological ranges of urine levels.