Increased Chloride Reabsorption as an Inherited Renal Tubular Defect in Familial Type II Pseudohypoaldosteronism

HYPERKALEMIA is a common electrolyte disorder. Among its common causes are renal insufficiency; adrenal insufficiency; hyporeninemic hypoaldosteronism, usually associated with diabetes mellitus, mild renal insufficiency, tubulointerstitial nephritis, or a combination of these conditions; isolated hypoaldosteronism; and pseudohypoaldosteronism, a disorder characterized by salt wasting, hypotension, and aldosterone resistance. There also exists a rare hyperkalemic syndrome associated with a normal glomerular filtration rate and hypertension.1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Although several hypotheses have been proposed to explain the impaired renal potassium secretion in this hyperkalemic syndrome, its exact pathogenesis, especially at the molecular level, is not known. Schambelan et al.17 made the intriguing observation that renal . . .