Question:medium
An 8 days old male infant was brought in a state of dehydration and shock. Examination revealed hyperpigmentation over the body with normal external genitalia. Blood tests revealed hypoglycemia, Na = 124 mEq/L and K = 7 mEq/L. What is the probable diagnosis?
An 8 days old male infant was brought in a state of dehydration and shock. Examination revealed hyperpigmentation over the body with normal external genitalia. Blood tests revealed hypoglycemia, Na = 124 mEq/L and K = 7 mEq/L. What is the probable diagnosis?
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Neonate with low sodium, high potassium, low sugar and hyperpigmentation equals salt-wasting adrenal failure.
Updated On: Jun 24, 2026
- Congenital adrenal hyperplasia
- Adrenal haemorrhage and shock
- Acute gastroenteritis with dehydration
- Hyperaldosteronism
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The Correct Option is A
Solution and Explanation
Read the laboratory triad first: sodium is low at 124, potassium is high at 7, and the blood sugar is low, all in a dehydrated, shocked neonate. Low sodium with high potassium is the signature of mineralocorticoid (aldosterone) failure, and the added hypoglycemia points to glucocorticoid (cortisol) failure as well, so both adrenal steroid pathways are deficient.
Now add the skin. Generalised hyperpigmentation in a newborn reflects a high ACTH drive, because when cortisol is low the pituitary pours out ACTH, whose precursor also stimulates melanocytes. That tells you the adrenal problem has been present and stimulating ACTH from early on.
The condition that combines a salt-losing state (low cortisol and low aldosterone), hypoglycemia and hyperpigmentation presenting around the end of the first week of life is the salt-wasting form of congenital adrenal hyperplasia, usually from 21-hydroxylase deficiency. In a male the external genitalia commonly look normal, so their normality does not exclude the diagnosis.
The distractors fail: adrenal haemorrhage is acute and would not give chronic pigmentation, gastroenteritis does not explain the pigmentation and steroid-failure electrolytes, and hyperaldosteronism would produce low potassium and high blood pressure, the reverse of what is seen.
Hence the diagnosis is congenital adrenal hyperplasia.
\[\boxed{\text{Congenital adrenal hyperplasia}}\]
Now add the skin. Generalised hyperpigmentation in a newborn reflects a high ACTH drive, because when cortisol is low the pituitary pours out ACTH, whose precursor also stimulates melanocytes. That tells you the adrenal problem has been present and stimulating ACTH from early on.
The condition that combines a salt-losing state (low cortisol and low aldosterone), hypoglycemia and hyperpigmentation presenting around the end of the first week of life is the salt-wasting form of congenital adrenal hyperplasia, usually from 21-hydroxylase deficiency. In a male the external genitalia commonly look normal, so their normality does not exclude the diagnosis.
The distractors fail: adrenal haemorrhage is acute and would not give chronic pigmentation, gastroenteritis does not explain the pigmentation and steroid-failure electrolytes, and hyperaldosteronism would produce low potassium and high blood pressure, the reverse of what is seen.
Hence the diagnosis is congenital adrenal hyperplasia.
\[\boxed{\text{Congenital adrenal hyperplasia}}\]
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