Pseudohypoaldosteronisms, report on a 10-patient series
1 Centre de référence des maladies rénales héréditaires, Département de pédiatrie, Hôpital Edouard-Herriot and Université Lyon 1, France 2 Département de pédiatrie, Hôpital Nord, Saint-Etienne, France 3 Service de génétique, Hôpital Européen Georges Pompidou, Paris, France 4 Institute of Pharmacology and Toxicology, University of Lausanne, Switzerland 5 Service de pédiatrie, Centre hospitalier territorial, Nouméa, Nouvelle-Calédonie, France 6 Service d'endocrinologie pédiatrique, Hôpital Debrousse and Université Claude Bernard, Lyon, France 7 INSERM U772, Collège de France, Paris, France
Correspondence and offprint requests to: Pierre Cochat, Département de pédiatrie, Hôpital Edouard-Herriot, 69437 Lyon cedex 03, France. Tel: +33-4-72110346; Fax: +33-4-72110343; E-mail: pierre.cochat{at}chu-lyon.fr
| Abstract |
|---|
Background. Type 1 pseudohypoaldosteronism (PHA1) is a salt-wasting syndrome caused by mineralocorticoid resistance. Autosomal recessive and dominant hereditary forms are caused by Epithelial Na Channel and Mineralocorticoid Receptor mutation respectively, while secondary PHA1 is usually associated with urological problems.
Methods. Ten patients were studied in four French pediatric units in order to characterize PHA1 spectrum in infants. Patients were selected by chart review. Genetic, clinical and biochemistry data were collected and analyzed.
Results. Autosomal recessive PHA1 (n = 3) was diagnosed at 6 and 7 days of life in three patients presenting with severe hyperkalaemia and weight loss. After 8 months, 3 and 5 years on follow-up, neurological development and longitudinal growth was normal with high sodium supplementation.
Autosomal dominant PHA1 (n = 4) was revealed at 15, 19, 22 and 30 days of life because of failure to thrive. At 8 months, 3 and 21 years of age, longitudinal growth was normal in three patients who were given salt supplementation; no significant catch-up growth was obtained in the last patient at 20 months of age.
Secondary PHA1 (n = 3) was diagnosed at 11, 26 days and 5 months of life concomitantly with acute pyelonephritis in three children with either renal hypoplasia, urinary duplication or bilateral megaureter. The outcome was favourable and salt supplementation was discontinued after 3, 11 and 13 months.
Conclusions. PHA1 should be suspected in case of severe hyperkalemia and weight loss in infants and need careful management. Pathogenesis of secondary PHA1 is still challenging and further studies are mandatory to highlight the link between infection, developing urinary tract and pseudohypoaldosteronism.
Keywords: acute pyelonephritis; mineralocorticoid resistance; pseudohypoaldosteronism; tubulopathy; urinary tract malformation
Received for publication: 2. 8.06
Accepted in revised form: 14.11.07