Cadmium nephropathy: monitoring for early evidence of renal dysfunction

Prospective studies in humans comparing various tests of cadmium-induced nephropathy have not been reported. Consequently, it is not possible to ascertain which screening methods should be followed in order to detect early nephropathy at a reversible stage. To obtain such data, the authors studied 23 cadmium workers with periodic analyses of blood/urine cadmium levels, hair cadmium content, urinary cytologies, creatinine clearance and urinary levels of lysozyme, beta-2-microglobulins, immunoglobulins, and aminoacids. Blood/urine levels were useful only as indices of acute environmental exposure and not as predictors of total body content or possible nephropathy. Hair content was elevated in most workers. Urine cytology was not reliable. Until further data are available, it is suggested that all five measures of renal function be used in screening and follow-up of cadmium workers for preventing nephropathy.