Inhibin B and AMH for Diagnosis of Hypogonadotropic Hypogonadism in Boys Under 1 Year of Age: A Case-control Study.

CONTEXT: Congenital hypogonadotropic hypogonadism (CHH) in infant boys is a rare disorder that can manifest as micropenis and/or cryptorchidism. Mini-puberty is considered a window of opportunity for CHH diagnosis and treatment. The lack of testosterone (T) elevation during this period is the gold standard for CHH diagnosis, but hormonal evaluation is not always available at this time.

OBJECTIVES

The aim was to compare inhibin B (INHB), anti-Müllerian hormone (AMH), T, LH, and FSH between infant boys (1 to 365 days) with micropenis and/or cryptorchidism due to isolated CHH (iCHH), CHH as part of combined pituitary hormone deficiency (CPHD), or of idiopathic origin (controls) and to determine discriminating cutoffs for CHH diagnosis based on sensitivity (Se) and specificity (Sp).

METHODS

This multicenter study from 7 University Hospitals in France included 138 boys aged 0 to 12 months (58 with iCHH, including 28 with a positive molecular diagnosis, 32 with CPHD, and 48 controls). Four periods of interest were studied: between 1 to 4 days, 15 to 65 days (early mini-puberty, corresponding to the T peak), 66 to 179 days (late mini-puberty), and 180 to 365 days (post mini-puberty).

RESULTS

Out of mini-puberty, the best-discriminating hormones were INHB between 1 to 4 days (Se/Sp 100%/75% at 150 pg/mL and 89%/100% at 85 pg/mL) and INHB and AMH after 180 days (INHB: Se/Sp 100%/100% at 100 pg/mL; AMH: Se/Sp 100%/92% at 600 pmol/L, and 75%/100% at 370 pmol/L). INHB and/or AMH discriminating performances were good (area under the receiver operating characteristic curve ≥ 0.95) across all 4 periods.

CONCLUSION

Inhibin B and/or AMH can be used to diagnose CHH in boys < 1 year of age.