Endocrine Abstracts

Autoimmune Addison’s disease (AAD) is widely believed to be associated with total loss of endogenous mineralocorticoid and glucocorticoid production and secretion, due to cell-mediated immune destruction. Therefore, patients with AAD are prescribed lifelong mineralocorticoid and glucocorticoid replacement therapy. We present a case of a 69 year old women known with polyglandular autoimmune disease type 2 (hypothyroidism, Addison’s disease and premature ovarian failure) diagnosed 30 years ago, who required full replacement therapy with glucocorticoids, while mineralocorticoid replacement could be withheld. Several times through the disease course, replacement therapy with low dose synthetic mineralocorticoid was initiated, but had to be withdrawn due to development of hypertension, hypokalaemia and marked oedema of the lower limbs. Blood samples showed residual aldosterone secretion, albeit with high renin levels. After interruption of fludrocortisone acetate, she had persistent normal blood pressure, sodium levels and high normal potassium levels. She was recently admitted for a first severe Addison crisis due to SARS-CoV-2 infection. The patient presented with marked hyperkalaemia and low sodium levels, reacting quickly to stress glucocorticoid replacement therapy. Under three times 20 mg of hydrocortisone daily, aldosterone was not measurable and plasma renin increased to 62 ng/l (normal values: 0.1–16.1 ng/l), indicating variable residual mineralocorticoid secretion. This case highlights the possible variability among patients with AAD in residual adrenal function, questioning the dogma of total loss of function currently accepted in endocrinology. Indeed, a recent study shows variable residual mineralocorticoid and glucocorticoids levels in blood of patients with AAD. In some case reports the documentation of residual or recovered glucocorticoid secretion lead to the tapering or withdrawal of hydrocortisone substitution therapy. To the best of our knowledge, this has not been documented for mineralocorticoid substitution therapy. The clinical significance and impact of measurable steroid production by the adrenal glands on treatment remains ill defined. It does not preclude Addison crisis, as illustrated in the present case report. Regular re-assessment of adrenal function should be performed in patient with AAD, in particular in the presence of symptoms of over substation in order to identify cases that can benefit from temporary decrease of glucocorticoid or mineralocorticoid substitution therapy. Even in this setting patient should be educated to adapt or recover treatment in stress situations to avoid Addison crisis.