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Zorluk: Çok zorPediatric Endocrine Disorders

Match the following rare congenital adrenal hyperplasia variants and related steroidogenesis defects with their most characteristic clinical and laboratory presentations in neonates.

  • 11-beta-hydroxylase deficiency46,XX infant with severe virilization, hypertension, hypokalemia, and markedly elevated serum 11-deoxycortisol
  • 17-alpha-hydroxylase deficiency46,XY infant with phenotypically female external genitalia, a blind vaginal pouch, hypertension, hypokalemia, and low serum testosterone
  • 3-beta-hydroxysteroid dehydrogenase deficiency46,XY infant with ambiguous genitalia, hyponatremia, hyperkalemia, and an elevated ratio of 17-hydroxypregnenolone to 17-hydroxyprogesterone
  • Cytochrome P450 oxidoreductase deficiency46,XX infant with ambiguous genitalia, severe midface hypoplasia, radiohumeral synostosis, and a history of maternal virilization during the pregnancy

Cevap

11-beta-hydroxylase deficiency matches the hypertensive, virilized 46,XX infant. 17-alpha-hydroxylase deficiency matches the hypertensive, undervirilized 46,XY infant. 3-beta-hydroxysteroid dehydrogenase deficiency matches the salt-wasting infant with elevated 17-hydroxypregnenolone. Cytochrome P450 oxidoreductase deficiency matches the infant with skeletal anomalies and a history of maternal virilization.
Each specific steroidogenesis defect results in a unique clinical signature based on deficient hormones and accumulated precursors. 11-beta-hydroxylase deficiency uniquely combines hypertension with virilization due to DOC and androgen accumulation. 17-alpha-hydroxylase deficiency combines hypertension with undervirilization due to blocked sex steroid synthesis. 3-beta-hydroxysteroid dehydrogenase deficiency impairs all three pathways, elevating delta-5 steroids. Cytochrome P450 oxidoreductase deficiency affects multiple P450 enzymes, uniquely presenting with Antley-Bixler skeletal anomalies and maternal virilization.

Adım Adım Çözüm

1
Evaluate each clinical presentation for markers of mineralocorticoid activity and sex steroid production.
Identified two hypertensive profiles (mineralocorticoid excess), one salt-wasting profile (mineralocorticoid deficiency), and one dysmorphic profile with maternal virilization.
Blood pressure and potassium levels indicate the state of the mineralocorticoid pathway, while external genitalia in relation to the karyotype indicates the state of the sex steroid pathway.
2
Differentiate the two hypertensive profiles.
The virilized 46,XX infant with hypertension corresponds to 11-beta-hydroxylase deficiency. The undervirilized 46,XY infant with hypertension corresponds to 17-alpha-hydroxylase deficiency.
Both conditions cause DOC accumulation (hypertension). However, 11-beta-hydroxylase deficiency shunts precursors to androgens (causing virilization), whereas 17-alpha-hydroxylase deficiency blocks androgen synthesis entirely (causing undervirilization).
3
Assign the remaining unique presentations to their corresponding complex enzymatic defects.
The salt-wasting infant with high 17-hydroxypregnenolone matches 3-beta-hydroxysteroid dehydrogenase deficiency. The infant with skeletal anomalies and maternal virilization matches Cytochrome P450 oxidoreductase deficiency.
3-beta-HSD deficiency characteristically elevates delta-5 steroids like 17-hydroxypregnenolone. POR deficiency uniquely causes Antley-Bixler syndrome and placental aromatase deficiency (leading to maternal virilization).

Anahtar Kavram

Differential diagnosis of rare congenital adrenal hyperplasia variants and steroidogenesis defects based on specific hormonal and clinical phenotypes.
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Konular

Pediatric Endocrine Disorders

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