ADRENAL-FUNCTION IN PATIENTS WITH CHRONIC-RENAL-FAILURE

Previous studies have reported divergent findings on the function of t he hypothalamic-pituitary-adrenal axis in patients with chronic renal failure (CRF). The low-dose adrenocorticotropin (ACTH) test offers the possibility of unmasking adrenal dysfunction, which might remain undi scovered using the ACTH test with the standard 250-mu g dose. Furtherm ore, the choice of renal replacement therapy (either hemodialysis or c ontinuous ambulatory peritoneal dialysis [CAPD]) might have an impact on adrenal function. To investigate these possibilities, ACTH tests we re performed with three different doses (ie, 1, 5, and 250 mu g) in 14 CRF patients and in seven healthy controls. Seven of the CRF patients were receiving chronic hemodialysis and seven were receiving CAPD. Ba sal plasma concentrations of cortisol were comparable in the three gro ups tested (5.3 +/- 0.4 mu g/dL In the controls, 6.6 +/- 0.7 mu g/dL i n the hemodialysis patients, and 7.9 +/- 1.0 mu g/dL in the CAPD patie nts), whereas basal ACTH concentrations were significantly elevated in the CRF patients (28.5 +/- 3.8 pg/mL in the hemodialysis patients and 33.0 +/- 6.0 pg/mL in the CAPD patients) when compared with normal co ntrols (17.0 +/- 1.4 pg/mL; P < 0.05). All three doses of ACTH resulte d in a rapid increase of plasma cortisol concentrations that was compa rable In all three groups. In the hemodialysis patients, a trend towar d a diminished response to the lowest dose of 1 mu g was noticed. We c onclude, therefore, that adrenal response to ACTH in various doses is unaffected in CRF independent of whether hemodialysis or CAPD is chose n for renal replacement therapy. (C) 1998 by the National Kidney Found ation, Inc.