Tests of adrenomedullary function are of no clinical relevance and are therefore not normally performed. Infusion of 2-deoxy-D-glucose has been shown to stimulate adrenalin output in idiopathic Addison's disease, but has minimal effect in tuberculous Addison's. This is in keeping with the histology which shows that, in the tuberculous disease, the whole gland is often destroyed.
Plasma electrolyte concentrations are not infrequently normal but may show the classical picture of hyponatraemia, hyperkalaemia, and elevated levels of urea.
Serum aldosterone levels may be normal or low, but plasma renin activity is elevated.
