C-11 Hydroxylase Deficiency Differential Diagnoses

Updated: May 25, 2021
  • Author: Gabriel I Uwaifo, MD; Chief Editor: George T Griffing, MD  more...
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Diagnostic Considerations

Polycystic ovarian syndrome (PCOS) is one of the most important differential diagnoses of late-onset (nonclassic) variants of virilizing CAH. PCOS is characterized by hirsutism, virilism, hyperandrogenism, menstrual irregularities, chronic anovulation, obesity, insulin resistance, acanthosis nigricans, multiple ovarian cysts, and an elevated ratio of luteinizing hormone (LH) to follicle-stimulating hormone (FSH). The elevated LH-to-FSH ratio and significant insulin resistance are useful discriminant laboratory findings.

CAH is far less common than PCOS. The best means of distinguishing CAH from PCOS is by measuring the levels of the appropriate metabolite after 250 mcg of ACTH (11-deoxycortisol in 11-beta-hydroxylase deficiency).

Differential Diagnoses