Selective aldosterone deficiency

Selective Aldosterone Deficiency (Type IV RTA). In type IV RTA, there is failure of distal potassium and hydrogen ion secretion because of aldosterone deficiency or resistance. This may occur because of a range of steroid or steroid receptor synthetic defects or because of hyporeninemic hypoaldosteronism (e.g., due to diabetic nephropathy, tubulointerstitial disease, urinary obstruction, renal transplantation, or SLE). Hyperkalemia, although mild, is a usual manifestation. 

Ashouri OS. Hyperkalemic distal tubular acidosis and selective aldosterone deficiency combination in a patient with lead nephropathy. Arch Intern Med 1985 145 1306-1307. 

Congenital adrenal hyperplasia Primary adrenal insufficiency Secondary adrenal insufficiency Selective aldosterone deficiency Musculoskeletal Diseases Mixed connective tissue syndromes Polymyalgia rheumatica Polymyositis Rheumatoid arthritis... 

Keidar S, Hayek T, Kaplan M, et al. Effect of eplerenone, a selective aldosterone blocker, on blood pressure, serum and macrophage oxidative stress, and atherosclerosis in apolipoprotein E-deficient mice. J Cardiovasc Pharmacol 2003 41 955-963. 

Hypoaldosteronism is rare and usually is associated with low renin status, diabetes, complete heart block, or severe postural hypotension, or it may occur postoperatively following tumor removal. Hypoaldosteronism may be part of a larger adrenal insufficiency or be the only defect the patient has. In nonselective hypoaldosteronism, the etiology of the low aldosterone is most likely generalized adrenocortical insufficiency (see Addison s disease). In selective hypoaldosteronism, the etiology is usually a specific defect in the stimulation of adrenal aldosterone secretion (21-hydroxylase deficiency being most common) or a defect in peripheral aldosterone action (decreased aldosterone receptors). 

Quantitative urinary steroid profiling by GC-MS using selective ion monitoring (SIM) provides much higher sensitivity, but is a more selective approach. It enables one to further determine aldosterone and 18-hydroxylated cortisol metabolites in hypertension research [10], and in different steroid enzyme deficiencies [3]. 

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