[Clinical significance of beta-2-microglobulin in diabetes mellitus]

The beta-2-microglobulin (B2M) level of the serum and urine was determined in 61 diabetics and 15 control patients by enzyme-immunoassay, to asses the value of B2M in clinical diagnosis. In patients with daily protein excretion exceeding 300 mg there was a significant positive correlation between serum creatinine, daily (24-hour) protein excretion, and B2M level of the serum and urine. In patients with less than 300 mg and in those with more than 300 mg daily protein excretion the B2M levels of the serum and urine were significantly higher than in the controls. Serum creatinine level underwent a significant rise only in patients with more than 1000 mg daily protein excretion. Determination of the B2M level is a sensitive method in the diagnosis of diabetic nephropathy. Simultaneous measurement of B2M level in the serum and urine detects nephropathy at an early stage and thus it may be of value in the prevention of the disease.