Increased serum angiotensin-converting enzyme in chronic renal disease.

Serum angiotensin-converting enzyme (SACE) was significantly elevated in 16 of 48 patients with various types of chronic renal disease not on hemodialysis [45.6 +/- (SD) 16.7 nmol/min/ml, p less than 0.001] and in 17 of 52 patients with chronic renal disease on maintenance hemodialysis (43.2 +/- 13.8, p less than 0.001) in comparison with 58 healthy adult controls (32.2 +/- 9.8). There was no significant relationship between SACE and renal function as indicated by serum creatinine and creatinine clearance, or the presence or absence of maintenance hemodialysis, except for a transiently increased elevation of SACE immediately post-dialysis due to hemoconcentration. There was a statistically insignificant positive correlation between SACE and 24-hour urinary protein excretion (r = 0.254, n = 21). Mean blood pressure measured in patients on maintenance hemodialysis was inversely related to SACE (p less than 0.05) following dialysis. Chronic renal disease irrespective of severity and therapy tends to be associated with elevated SACE and must be considered in the evaluation of sarcoidosis.