quick review Primary AI : all the layers are affected, hence, aldosterone, cortisol and androgens are decreased Now, Central AI : only cortisol and androgens are low. Since, aldosterone isn't dependent on ACTH. the question here is, what will the levels of renin, aldosterone be in secondary and tertiary disease? according to wiki it will be low, i don't get why though? https://en.wikipedia.org/wiki/Adrenal_insufficiency any inputs here?