Mineralocorticoid Unresponsiveness with Severe Neonatal Hyponatremia and Hyperkalemia

Abstract

An infant with severe neonatal hyponatremia and hyperkalemia is described. Although marked elevations of urinary 17-hydroxycorticosteroids suggested an 18-dehydrogenase aldosterone biosynthetic defect, the infant proved to have mineralocorticoid unresponsiveness, or pseudohypoaldosteronism. Dietary sodium supplementation and ion exchange resin administration resulted in normalization of serum electrolytes and urinary 17-hydroxycorticosteroids. ACTH infusion produced natriuresis, suggesting the need for additional sodium supplementation during the stress of illness, with a resultant increase in ACTH secretion. Determinations of the relative amounts of urinary 18-hydroxy and aldosterone metabolites appear necessary for early definitive diagnosis of the disorder.

Pseudohypoaldosteronism in a Female Infant and Her Family: Diversity of Clinical Expression and Mode of Inheritance

“…Pseudohypoaldosteronism (PHA) is a rare disorder first reported by Cheek & Perry in 1958 (1) in an infant with a severe salt losing syndrome. In most cases the disorder has been characterized by hyponatremia, hyperkalemia and dehydration despite hyperaldosteronism (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15). Those findings seem to be caused by renal tubular refractoriness to mineralocorticoids.…”

Renal Tubular Hyperkalemia

“…It is characterized by failure to thrive, renal sodium wasting, hyponatremia, metabolic acidosis and elevated plasma renin activity and plasma aldosterone concentration [9][10][11][12][13][14], The disor der has to be distinguished from hypoaldosteronism asso ciated with adrenal biosynthetic abnormalities [39], The abnormality in pseudohypoaldosteronism is not cor rected by administration of exogenous mineralocorticoids, and treatment consists of a high sodium intake until the condition spontaneously disappears, usually after the age of 2-3 years. No structural renal lesion or adrenal abnormalities have been reported in this condi tion, and recent data suggest a genetic predisposition [13] The pathogenesis of this syndrome has not been eluci dated.…”

Severe pseudohypoaldosteronism in a pair of twins not associated with hydramnios

“…Since the first description of a patient with PHA in 1958 by Cheek and Perry [2], about 70 additional patients have been reported [3]. Clinically, the disease varies in severity, being self limited in most instances and spontaneous remission occurs within the first 2 -3 years of life [4 -6].…”