Effects of chronic phthalate exposure on the kidney

Several investigators have reported the finding of polycystic kidney disease (PKD) at autopsy in patients who had undergone long-term hemodialysis for renal failure due to causes other than PKD. We initiated studies to determine whether the drugs or chemicals to which patients on dialysis are exposed could be responsible for these cystic changes. Adult rats were tube fed chemical residues from an artificial kidney or phthalate esters [di(2-ethylhexyl) phthalate, DEHP], which are a main component of these plastic kidneys or a control solution. Rats receiving DEHP or residues showed a significantly higher incidence of focal cysts when compared to controls. Rats receiving DEHP developed a significant decrease in kidney function as demonstrated by creatinine clearance, and these animals had the highest tissue levels of measureable DEHP. We postulate that patients receiving long-term dialysis may acquire PKD secondary to their exposure to chemicals leached from artificial kidneys.