HYPERPROLACTINAEMIA IN RENAL DISEASE

Abstract
Basal prolactin concentrations in 357 patients with renal disease of defined pathology were compared with those in 210 control subjects. Elevated prolactin concentrations were found in 113 renal patients (32%) including 53 patients in whom elevated concentrations were possibly attributable to drug therapy. In the 60 patients who had hyperprolactinaemia not attributable to drugs, elevated concentrations (P < 0.005) were found exclusively in patients with impaired renal function. A significant correlation was observed between prolactin and creatinine concentrations in these patients (r [correlation coefficient] = 0.45 P < 0.005) and prolactin reverted towards normal after successful renal transplantation. A significant arteriovenous prolactin concentration difference across the kidney (mean 16% range 8-29% P < 0.02) was found in 7 patients with non-renal non-endocrine disease. The hyperprolactinaemia found commonly in patients with impaired renal function is only partly attributable to drug therapy. The positive correlation between prolactin and creatinine reversion of prolactin towards normal after successful transplantation and arteriovenous hormone concentration differences across the normal kidney suggests that the kidney has an important role in prolactin metabolism. Abnormal regulation of prolactin secretion in renal failure may also be involved.