Endocrine Abstracts

Resistant hypertension of endocrine cause can make for a challenging diagnosis but it certainly is a very important one.

Case report: We present the case of a 65 year old male patient with a history of arterial hypertension and hypokalemia for the past 10 years, for which he was prescribed a combination of alpha and beta blockers, calcium channel blockers, angiotensin receptor blockers (ARBs), loop diuretic, and spironolactone. The lack of response to this treatment suggested a possible endocrine cause and he was admitted to our clinic for further investigation. The blood biochemistry confirmed the hypokalemia (2, 9 mmol/l) and the endocrine panel showed high normal aldosterone levels (145 pg/ml), suppressed renin (0, 96 pg/ml) with an aldosterone/renin ratio (ARR) of 15, 1 ng/dl, and normal levels of metanephrines and normetanephrines. Additionally, we tested the serum cortisol and ACTH and performed 1 mg overnight dexamethasone test and 2 mg two-day dexamethasone test with lack of suppression with a slight increase of the blood pressure after the latter. Rising the spironolactone dose did manage to normalize the potassium levels, but the blood pressure remained high. The abdominal CT scan revealed bilateral macronodular adrenal hyperplasia and the pituitary MRI a microadenoma thus indicating that further investigations, such as adrenal venous sampling (AVS) and inferior petrosal sinus sampling could be needed in order to establish a correct diagnosis and treatment plan.

Conclusions: When facing with a patient with severe secondary hypertension it is important to search thoroughly for the endocrine imbalance since the results can sometimes be misleading and disorders could concur.