[Diagnosis of adrenal diseases focusing on morphological and endocrinological viewpoints]

The recent advances in the diagnosis of adrenal diseases owe much to the rapid progress in radiological and endocrinological areas. The former is ascribed to the progress of medical electronics. The latter has been realized by the development, improvement and spread of the measurement of a very small amount of hormones or hormone-like substances in blood, urine or tissues, supported by the improvement of measurement instruments as well as the immunoassay or chemical assay techniques. This paper reviews approaches to diagnosis of adrenal diseases causing hypertension and asymptomatic, incidentally discovered adrenal tumors. Incidentally discovered adrenal tumors have increased owing to the spread of medical electronic instruments such as abdominal ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI). Discrimination of malignancy is an important clinical concern. More than 90% of the tumors reported in the Japanese were larger than 3 cm in diameter. The diagnosis of primary aldosteronism has been made by the measurement of plasma renin and aldosterone, CT and 131I-cholesterol scintigraphy. However the differential diagnosis of adrenal adenoma from bilateral adrenal hyperplasia has remained as a problem. There were a few patients in whom adrenal adenomas appeared after 2-3 years' follow-up period. In Cushing's syndrome, tumors are found with ease by US, CT and MRI. The diagnosis of pheochromocytoma is made mainly by urinary catecholamines and metabolites including metanephrine, normetanephrine and VMA. US, CT and MRI are very useful. Diagnosis and discovery of metastasis will be more reliably made when 131I-MIBG comes to the clinical stage.(ABSTRACT TRUNCATED AT 250 WORDS)