Endocrine Abstracts

JOINT1076

Background: Nontumorous premature pubarche is rare in infants, as the physiological variations in the gonadal and adrenal axes during mini-puberty make etiological diagnosis challenging.

Purpose: To report a case of self-limited premature pubarche in a 5⁺-mo-old male infant with nonclassical congenital adrenal hyperplasia (NCCAH).

Methods: Case study.

Results: A 5⁺-mo-old male infant was referred to our clinic due to be found with the presence of pubic hair for 8 days. Being the second child of non-consanguineous Chinese parents, he was born by cesarean section due to premature rupture of membranes in pre-term with appropriate weight and length in good condition (36⁺⁵ weeks, 2500g,48cm). At 3-mo-old, he was diagnosed with“eczema”and administered with topical glucocorticoids intermittently for 2⁺ months until now. At 4-mo-old, serum 17OHP was tested to be 2.63 ng/ml due to vomiting. Physical examination revealed thick and long pubic hair on the mons pubis-without hyperpigmentation or enlargement of the penis. His height (–0.04 SDS) and weight (-0.9 SDS) were normal for his age. Laboratory test: E₂ 21 pg/ml, T 0.67 ng/ml, P 0.20 ng/ml, DHEAs 3.34μmol/l, cortisol 8.6μg/dl, ACTH 10.2 pmol/l, androstenedione(A⁴) <1.05 nmol/L. Serum β-hCG, AFP and CEA were normal. At 7⁺-mo-old(one month after topical steroid withdrawal), the patient was admitted to the hospital due to slightly aggravated pubic hair development. Physical examination revealed scattered large patches of papular rash on the trunk, one acne on the face, and 4 ml testis. GnRHa (triptorelin) 60-minute stimulation test: FSH 1.05→3.02 IU/l, LH 1.13→11.39 IU/L; 8-hour ACTH stimulation test: 17OHP 2.01→18.03 ng/ml, cortisol 5.8→48.8μg/dl, P 0.30→1.8 ng/ml, E₂ 12→51 pg/ml, T 0.38→0.13 ng/ml, A⁴ <1.05→1.29 nmol/l, DHEA_S 1.57→1.92μmol/L. Bone age was 9 months. Testicular ultrasound, adrenal CT, pituitary MRI did not show any abnormalities. Due to his elevated base and ACTH-stimulated serum 17OHP concentration, Whole exome sequencing and CYP21A2 gene analysis (Sanger sequencing and MLPA) were performed and revealed negative result. At 3y3m, the boy’s pubarche spontaneously resolved at age 10⁺-mo-old after a slightly increase and darkening for one more month, with no other signs of virilization, and growth velocity remained normal.

Conclusions: We report a rare self-limited premature pubarche case of a male infant in mini-puberty with biochemical NCCAH. The premature pubarche is not related to NCCAH.

Key words: Mini-puberty, non-classical congenital adrenal hyperplasia, premature pubarche.