Environmentally related diseases of the urinary tract.

Nephrotoxicity from exposure to therapeutic agents and chemicals in the environment and workplace results in a broad spectrum of clinical renal disease that may mimic disorders from other causes. Nephrotoxic agents may, in fact, be responsible for some fraction of renal disease of undetermined etiology. Specific diagnosis and treatment by removal from exposure to the toxic agent is more likely in the early phase of the disorder. Measurement and characterization of proteinuria provides the most sensitive and reliable method of early detection. Increased urinary excretion of serum proteins with molecular weight in excess of 50,000, such as albumin and transferrin, is an early indicator of glomerular injury. Low-molecular-weight proteinuria (beta 2-microglobulin or retinol-binding protein) and enzymuria, particularly excretion of NAG, are sensitive indicators of renal tubular cell injury. Tests that reflect hypersensitivity reactions are often indicative of immunologically mediated nephrotoxicity but are not specific for the kidney. Cancers of the kidney and urinary bladder appear to be increasing and are most common among the socially active and affluent. Susceptibility of the urinary tract to toxicity and carcinogenicity reflect contact of excreted toxins with the epithelial cells of nephrons and urinary bladder.