Pseudohipoaldosteronismo y aparente exceso de mineralocorticoides: cara y ceca en dos pacientes pediátricos / Pseudohypoaldosteronism and apparent mineralocorticoid excess: two faces, two pediatric patients

Los síndromes endocrinológicos con hipofunción o hiperfunción con niveles paradójicos de dosajes hormonales han sido bien caracterizados en los últimos años del siglo XX, a partir del desarrollo de técnicas genéticas y moleculares. Presentamos dos pacientes con pseudohipoaldosteronismo y aparente exceso de mineralocorticoides como síndromes en espejo, con la intención de alertar al médico clínico respecto de su consideración como entidad diagnóstica en niños con alteraciones hidroelectrolíticas. (AU)

Endocrinological syndromes with underactive or overactive hormonal levels with paradoxical dosages have been well characterized over the years of the twentieth century, from the development of genetic and molecular techniques. We present two patients with pseudohypoaldosteronism and apparent mineralocorticoid excess as mirror syndromes, with the aim to alert the clinician regarding their consideration as a diagnostic entity in children with fluid and electrolyte disturbances. (AU)

Presentación de casos clínicos Seudohipoaldosteronismo de tipo 1: una emergencia hidroelectrolítica infrecuente. Comunicación de cuatro casos / Pseudohypoaldosteronism type 1: an uncommon electrolyte emergency. Report of four cases

El seudohipoaldosteronismo de tipo 1 es un síndrome infrecuente de resistencia a la aldosterona que se manifiesta con pérdida salina, hiponatremia, hiperpotasemia, acidosis metabólica hiperclorémica e hiperaldosteronismo hiperreninémico. El síndrome puede ser genético; secundario a uropatías e infección urinaria entre otras causas o presentarse esporádicamente. La pérdida salina puede ser sistémica y grave o localizada a nivel renal, por lo general, con mejor pronóstico. El cuadro clínico se manifiesta predominantemente en los primeros siete meses de vida; un marcado retraso pondoestatural y vómitos recurrentes suelen ser los signos clínicos habituales, rara vez se presenta como una emergencia hidroelectrolítica en forma de shock hipovolémico, arritmias cardíacas hiperpotasémicas y crisis convulsiva por hiponatremia. Se presentan cuatro pacientes que debutaron como una emergencia hidroelectrolítica.

Pseudohypoaldosteronism type 1 is a rare syndrome of resistance to aldosterone manifested by salt wasting, hyponatremia, hyperkalemia, hyperchloremic metabolic acidosis, and hiperreninemic hyperaldosteronism. The syndrome may be genetic, secondary to uropathies and urinary tract infection among other causes or it may occur sporadically. The salt wasting may be systemic and severe or localized to the kidney usually with better prognosis. The clinical picture is prevalent in the first seven months of life, failure to thrive and recurrent vomiting are usually the common clinical signs, an electrolyte emergency in the form of hypovolemic shock, hyperkalemic cardiac arrhythmias and hyponatremic seizures is rare. Four patients presenting with an electrolyte emergency are reported.

Salt wasting disorder in the newborn.

The clinical presentation of pseudohypoaldosteronism (PHA) mimics congenital adrenal hyperplasia (CAH). Poor response of the dehydration and electrolyte abnormalities to steroid therapy should make one suspect PHA. The treatment is supportive in the form of salt replacement and sodium resonium. We report a case of PHA that presented as salt wasting on the second day of life, initially appearing like CAH. The baby responded well to sodium resonium and salt replacement.

Osteopetrosis associated with hyperkalaemia: a case report

Osteopetrosis is a rare disease of childhood. We report a 4-month-old infant with clinical and radiological features of osteopetrosis who had dehydration and hyperkalaemia on admission and, during investigations, was found to have pseudohypoaldosteronism

Heterozygous Mutations of The Gene for Kir 1.1 (ROMK) in Antenatal Bartter Syndrome Presenting with Transient Hyperkalemia, Evolving to a Benign Course

Bartter-like syndrome encompasses a set of inherited renal tubular disorders associated with hypokalemic metabolic alkalosis, renal salt wasting, hyperreninemic hyperaldosteronism, and normal blood pressure. Antenatal Bartter syndrome, a subtype of Bartter-like syndrome, is characterized by polyhydramnios, premature delivery, life-threatening episodes of fever and dehydration during the early weeks of life, growth retardation, hypercalciuria, and early-onset nephrocalcinosis. Mutations in the bumetanide-sensitive Na-K-2Cl cotransporter (NKCC2) and ATP-sensitive inwardly rectifying potassium channel (ROMK) of the thick ascending limb of Henle's loop have been identified in the antenatal Bartter syndrome. We report the identification of two heterozygous mutations of the gene for Kir 1.1 (ROMK) from an antenatal Bartter syndrome patient who presented at birth with mild salt wasting and a biochemical findings that mimicked primary peudohypoaldosteronism type 1, such as hyperkalemia and hyponatremia, and evolved to a relatively benign course. We have identified amino acid exchanges Arg338Stop and Met357Thr in the gene exon 5 for ROMK by PCR and direct sequencing. Both mutations alter the C-terminus of the ROMK protein, and can affect channel function.