alpha 1-Microglobulin determination in urine for the early detection of renal tubular dysfunctions caused by exposure to cadmium.

The determination of alpha 1-microglobulin (alpha 1-m) in urine was compared with that of beta 2-microglobulin (beta 2-m) for the detection of renal tubular dysfunctions caused by exposure to cadmium. alpha 1-m In urine is stable down to pH 4.5, whereas beta 2-m degrades below pH 5.5. The relationship between the urinary pH and alpha 1-m or beta 2-m in urine showed that alpha 1-m was independent of urinary pH, whereas beta 2-m-concentration decreased as urinary pH fell to a pH level below 6. Without a pH effect, alpha 1-m was highly correlated with beta 2-m in urine (N = 174, r = 0.96) from Cd-polluted subjects with renal dysfunctions. Due to the greater stability of alpha 1-m in urine, alpha 1-m seemed to be more advantageous than beta 2-m for the detection of renal tubular dysfunctions caused by Cd.