Beta-2-microglobulin in the assessment of renal function of the transplanted kidney.

Plasma and urine beta-2-microglobulin (B2m) were measured in 37 renal transplant recipients and 34 healthy subjects. Serum B2m was found to be a more sensitive index of renal function than serum creatinine. Renal transplant recipients had significantly higher urine B2m when compared with normal controls. Normal subjects had a higher serum to urine B2m ratio (SUR) while those with renal impairment had a lower SUR. Serum B2m used alone or together with urine B2m and SUR appears a useful index for assessment of renal allograft function as well as detection of potential renal damage.