Neonatal Congenital Adrenal Hyperplasia: Immediate Evaluation and Management

Immediate Specialist Consultation

A newborn with an unusually large penis and bilaterally non‑palpable testes must receive an urgent pediatric endocrinology or pediatric urology consult to exclude potentially fatal congenital adrenal hyperplasia (CAH), because the infant may be genetically female (46,XX) with severe virilization. 1
Circumcision must be postponed until the full endocrine evaluation is completed to avoid irreversible incorrect sex assignment. 1
Failure to diagnose CAH promptly can precipitate life‑threatening shock, hyponatremia, and hyperkalemia due to the inability of many affected infants to regulate electrolytes. 1

Serum sodium and potassium should be measured immediately to identify an impending adrenal crisis characterized by hyponatremia and hyperkalemia. 1
An urgent karyotype analysis is required to determine whether the infant is 46,XX or 46,XY, guiding sex‑assignment decisions. [1][2]

A thorough external genital examination must document stretched penile length, presence of hypospadias, degree of labioscrotal fusion, and any urogenital sinus, providing essential phenotypic information for diagnosis and management. [1][2]

Continuous cardiorespiratory monitoring and close surveillance of vital signs are indicated for infants with suspected CAH and non‑palpable testes plus virilization. 1
Intravenous access should be obtained promptly, and fluid resuscitation prepared in case of shock signs. 1

Ultrasound or other imaging studies should not be ordered before specialist consultation because they have limited diagnostic performance (≈45 % sensitivity, ≈78 % specificity for non‑palpable testes) and can delay essential treatment. 1

Non‑palpable testes must not be assumed to represent simple cryptorchidism; a disorder of sexual development must be ruled out first. 1
Specialist consultation must not be delayed; each hour of postponement increases risk in CAH cases with salt loss. 1

When 46,XX status is confirmed in a CAH infant, female sex assignment is indicated because internal reproductive organs (uterus, ovaries) are intact, allowing normal sexual function and potential fertility. 2
Feminizing genitoplasty should be performed within the first two months of life if female sex is assigned, to achieve external genital appearance consistent with the rearing gender. 2
Although a higher proportion of these individuals report bisexual or homosexual orientation compared with the general population, the vast majority identify as women when sex assignment occurs early. 2
Late diagnosis or inadequate adrenal suppression is associated with an increased risk of gender dysphoria due to continued masculinization of the nervous system. 2