The principal condition of concern is failure of the adrenal gland cortex. The cause is most often autoimmune; tuberculosis or other infectious processes are less likely.
Symptoms generally consist in progressive weakness, weight loss, anorexia, vomiting. Occasionally decompensation can be abrupt (Addisonian Crisis) in the context of an acute illness. In this case, shock may be present (usually without hypoxaemia), hypotension and possibly death. Hyperkalaemia and hyponatremia may occur together, with possible related ECG changes, but are not always present. Addison disease may be accompanied by hyperpigmentation.
The diagnosis of primary adrenal failure is confirmed by low plasma cortisol (usually less than 100 nanomol/L, blood taken around 8 - 9 am), as well as lack of response to ACTH (Synacten test) with elevated ACTH level. CT imaging may be necessary and sometimes confirms an atrophic adrenal gland.
A Class 1 applicant with well controlled and stable disease may possibly be issued a medical certificate under the flexibility process. A “Not Valid for Single Pilot Air Operations Carrying Passengers” restriction and other restrictions are likely to apply.
A Class 2 applicant with well controlled and stable disease may possibly be issued a medical certificate under the flexibility process. Some restrictions may apply.
Note: Certificate holders on Prednisone or Hydrocortisone long term need ‘sick day’ rules. They need to understand that in the context of illness, particularly diarrhoea and vomiting where absorption of steroids is not reliable, they are in danger of adrenal crisis. They need supplementary oral of I.V. steroid cover if unwell. A medical alert bracelet is warranted. Licences holders must readily remove themselves from duty, even if only slightly unwell.