Primary aldosteronism with bilateral multiple aldosterone-producing adrenal adenomas

A 41-year-old woman developed primary aldosteronism due to bilateral multiple aldosterone-producing adenomas (APA), She was suspected to have idiopathic hyperaldosteronism (IHA) 7 years previously, Although preoperative data suggested APA and IHA was suspected in a postoperative microscopic specimen, a definite clinical diagnosis could not be made. Cytochrome P-450 and other enzymes involved in aldosterone synthesis were found in the tumor portions but not in the zona glomerulosa of attached adrenals, which histopathologically showed ''paradoxical hyperplasia''. This was a rare case of bilateral multiple APA, which could be differentiated from IHA by immunohistochemical analysis of adrenal steroidogenic enzymes.