BACKGROUND: Salt wasting syndrome (hyponatremia, hyperkalemia, dehydration, metabolic acidosis) in early infancy could be caused by either mineralocorticoid deficiency as in congenital adrenal hyperplasia (CAH) and adrenal insufficiency or mineralocorticoid resistance as in pseudohypoaldosteronism (PHA). In salt wasting CAH, serum aldosterone and cortisol levels are expected to be low. Cross reactivity between high levels of adrenal steroid precursors and aldosterone has recently been reported resulting in elevated aldosterone levels in CAH, leading to difficulty in differentiating between CAH and PHA. CASE PRESENTATION: We report four such cases of salt wasting CAH, where high aldosterone levels and high normal cortisol levels led to initial diagnostic confusion with PHA. Diagnosis of CAH was later established on the basis of significantly elevated adrenocorticotropic hormone (ACTH) stimulated 17-hydroxyprogesterone (17-OHP) values. CONCLUSIONS: By reporting these cases we draw attention to the possibility that high levels of adrenal steroid precursors can cross react with aldosterone and cortisol, and underscore the significance of ACTH stimulated 17-OHP values in differentiating CAH and PHA.
BACKGROUND:Saltwasting syndrome (hyponatremia, hyperkalemia, dehydration, metabolic acidosis) in early infancy could be caused by either mineralocorticoid deficiency as in congenital adrenal hyperplasia (CAH) and adrenal insufficiency or mineralocorticoid resistance as in pseudohypoaldosteronism (PHA). In salt wasting CAH, serum aldosterone and cortisol levels are expected to be low. Cross reactivity between high levels of adrenal steroid precursors and aldosterone has recently been reported resulting in elevated aldosterone levels in CAH, leading to difficulty in differentiating between CAH and PHA. CASE PRESENTATION: We report four such cases of salt wasting CAH, where high aldosterone levels and high normal cortisol levels led to initial diagnostic confusion with PHA. Diagnosis of CAH was later established on the basis of significantly elevated adrenocorticotropic hormone (ACTH) stimulated 17-hydroxyprogesterone (17-OHP) values. CONCLUSIONS: By reporting these cases we draw attention to the possibility that high levels of adrenal steroid precursors can cross react with aldosterone and cortisol, and underscore the significance of ACTH stimulated 17-OHP values in differentiating CAH and PHA.