Micronodular adrenal disease: a light and electron microscopic study.

A case of Cushing's syndrome due to micronodular adrenal disease in a 17-year-old girl is presented. The adrenals showed both black and yellow nodules. Histologically the cells contained lipofuschin and either had a clear cytoplasm or an eosinophilic cytoplasm with a prominent nucleus. Lymphocytes were a prominent feature. No cells of the zona reticularis were identified. The cell of origin of these nodules appeared to be from the inner layer of the zona fasciculata. We postulate that the disease is caused by an abnormality in the migration and ultimate destruction of cells from the zona fasciculata to the zona reticularis with a build up of cells at the interface zone.