Blood "Cortisol" Levels From Spironolactone

Abstract

To the Editor.— The recent report of Greenblatt and Koch-Weser 1 describing gynecomastia and impotence as complications of spironolactone therapy reminded us of a patient with another endocrine complication. In a 40-year-old man with progressive anasarca for two months, investigations suggested a diagnosis of idiopathic cardiomyopathy with passive congestion of the liver. A plasma cortisol level was obtained because of truncal obesity, abdominal striae, and impaired glucose tolerance. Plasma cortisol levels of 212 to 600μg/100 ml were reported (normal values 7-27). The patient had been receiving as much as 400 mg of spironolactone a day. The plasma cortisol concentrations were performed by the Mattingly method. Urinary steroid excretion was normal. The spurious elevation of plasma cortisol levels as determined by the Mattingly method in patients treated with spironolactone has been well established. 2,3 Awareness of this complication will prevent unnecessary investigation of abnormally elevated plasma cortisol. Wood et al 3