Cells of the zona fasciculata and zona reticularis lack aldosterone synthase (CYP11B2) that converts corticosterone to aldosterone, and thus these tissues produce only the weak mineralocorticoid corticosterone. However, both these zones do contain the CYP17A1 missing in zona glomerulosa and thus produce the major glucocorticoid, cortisol. Zona fasciculata and zona reticularis cells also contain CYP17A1, whose 17,20-lyase activity is responsible for producing the androgens, dehydroepiandosterone (DHEA) and androstenedione. Thus, fasciculata and reticularis cells can make corticosteroids and the adrenal androgens, but not aldosterone.
During minor illness (., flu or fever >38° C [° F]) the hydrocortisone dose should be doubled for 2 or 3 days. The inability to ingest hydrocortisone tablets warrants parenteral administration. Most patients can be educated to self administer hydrocortisone, 100 mg IM, and reduce the risk of an emergency room visit. Hydrocortisone, 75 mg/day, provides adequate glucocorticoid coverage for outpatient surgery. Parenteral hydrocortisone, 150 to 200 mg/day (in three or four divided doses), is needed for major surgery, with a rapid taper to normal replacement during the recovery. Patients taking more than 100 mg hydrocortisone/day do not need any additional mineralocorticoid replacement. All patients should wear some form of identification indicating their adrenal insufficiency status.
Treatment: If a pancreatic or liver tumor is identified and able to be surgically excised, the skin lesions may normalize for an extended period of time, but because these tumors metastasize (spread to other areas of the body) quickly, surgery is not curative. In cases of end stage liver disease, surgery is not possible, and the goal of therapy is to increase quality of life and decrease uncomfortable skin lesions with supportive care and addressing the nutritional abnormalities. Supportive care includes supplementing protein and necessary minerals and enzymes through the diet and oral supplements or by weekly intravenous amino acid infusions that are performed in the hospital on an outpatient basis until improvement in the skin is noted. Unfortunately, despite the supportive care, the disease will progress.