ISSN:
1432-1076
Keywords:
Adrenal cortex diseases
;
Adrenal gland diseases
;
Hypoaldosteronism
;
Steroid hydroxylases
;
Mineralocorticoids
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Infection-triggered, life-threatening salt-loss and hyperkalaemia developed in two male infants with wasting, inappropriately low plasma aldosterone concentrations and elevated plasma renin activity. The presumptive diagnosis of a defective terminal step in aldosterone biosynthesis was made by the presence of large amounts of 11-dehydrotetrahydrocorticosterone and its 18-hydroxylated metabolite (18-OH-THA), free 18-hydroxycorticosterone (18-OH-B) and 18-hydroxytetra-hydrocorticosterone in the urine of both patients. The diagnosis of corticosterone methyl oxidase type II (CMO II) deficiency was confirmed by an elevated urinary 18-OH-THA to tetrahydroaldosterone ratio in one boy and by an elevated plasma 18-OH-B to aldosterone ratio in the other boy. Unknown steroids responsible for the salt-loss were not identified. Sodium supplementation but not short-term high dose oral 9α-fluorcortisol (FF) normalized the hyponatraemia in one patient, in whom sodium (Na+)/potassium (K+) co-transport was decreased. Both patients eventually received long-term FF treatment to prevent impairment of longitudinal growth caused by chronic salt-loss. The diagnosis of CMO II deficiency should always be confirmed by elevated precursor-product ratios in urine or plasma, using radioimmunoassays with prior chromatographic separation. Metabolic studies as the short-term response of serum Na+ to high dose FF may not be helpful in differentiating aldosterone biosynthetic defects from endorgan resistance to mineralocorticoids.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01963554
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