Extraordinarily high aldosterone, 901.0 ng/dL, in a patient with primary aldosteronism: an insight into the underlying mechanism.

A 43-yr-old hypertensive male was admitted due to hypokalemia (1.8 mEq/L) and renal dysfunction (eGFR, 20.0 mL/min/1.73 m2). His plasma aldosterone was 901.0 ng/dL, plasma renin activity 5.7 ng/mL/hr, and aldosterone/renin activity ratio 158. Angiotensin II (AII) was 0.7 pg/mL, ACTH <1.0 pg/mL, and cortisol 21.6 µg/dL. Liquid chromatography-tandem mass spectrometry analysis showed that aldosterone (104 times the control) as well as its precursors were significantly elevated in the patient's plasma. A left adrenal (4-cm-diameter) tumor with 131I-Adosterol uptake was found and removed. Four days later, plasma aldosterone and renin activity had dropped to 7.73 ng/dL and 1.6 ng/mL/hr, respectively. However, they rose to 24.0 ng/dL and 10.9 ng/mL/hr, respectively, by Day 102. Nevertheless, magnetic resonance angiography found no evidence of a renovascular lesion. The tumor was a benign adrenocortical adenoma composed predominantly of clear cells positive for 17α-hydroxylase, [hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerases], and aldosterone synthase. A quantitative real-time polymerase chain reaction analysis of the tumor cells revealed that expression of the gene encoding aldosterone synthase was 85 times the control level. In addition, the tumor cells harbored G151R mutation of the inward rectifying potassium channel subfamily j, member 5 gene. The striking overexpression of aldosterone synthase by the tumor cells was considered the primary mechanism for the extravagant overproduction of aldosterone in this case. This overexpression may have resulted from integration of signals from AII and forced membrane depolarization due to the potassium channel mutation.

Hypoglycaemic coma due to adrenal failure in a chronic haemodialysis patient.

A 62-year-old man, receiving chronic haemodialysis and suffering from alcoholic liver cirrhosis and chronic pancreatitis, presented with hypoglycaemic coma. Plasma cortisol was undetectable (< 5.5 nmol/L) with suppressed adrenocorticotropic hormone (ACTH), which established a diagnosis of adrenal failure due to ACTH deficiency. Twenty-five milligrams of oral hydrocortisone eradicated hypoglycaemia. Presentation of adrenal failure in this patient was atypical because he was hypertensive, serum electrolytes including sodium were normal and anaemia was unremarkable, which were all due to end-stage renal disease and its treatment with haemodialysis. As far as we are aware, this is the first case report of hypoglycaemic coma due to adrenal failure in a chronic haemodialysis patient.