ADULT ANDROGENITAL (ADRENOGENITAL) SYNDROMES
Definition
- Adult adrenogenital syndromes: Disorders associated with excess adrenal androgens in adults.
- Causes:
- Late-onset (nonclassic) congenital adrenal hyperplasia (CAH)
- Familial glucocorticoid resistance
- Cushing syndrome (ACTH-dependent)
- Androgen-secreting adrenal neoplasms
- Gender Differences:
- In men, adrenal androgen excess may be clinically silent (because gonadal testosterone dominates).
- In women, leads to masculinization (virilization), menstrual dysfunction.
Clinical Features in Women
- Hirsutism
- Excessive male-pattern hair growth (cheeks, upper lip, chin, midline chest, male-type pubic hair pattern, etc.).
- Virilization (more severe androgen excess)
- Musculature: Increased muscle bulk, loss of female body contours.
- Voice: Deepening.
- Breasts: Atrophy.
- Clitoromegaly: Clitoris >10 mm length or >7 mm width = abnormal.
- Scalp Hair: Temporal balding.
- Androgenic Flush: Plethoric face, neck, upper chest.
LATE-ONSET (NONCLASSIC) CONGENITAL ADRENAL HYPERPLASIA
- Pathophysiology
- Milder/partial enzymatic blocks in steroidogenesis (3β-HSD, 21-hydroxylase, or 11β-hydroxylase).
- Present later in life with hirsutism, menstrual irregularities, ± mild virilization.
- 3β-Hydroxysteroid Dehydrogenase (3β-HSD) Deficiency
- Laboratory: ↑DHEA-S, low androstenedione.
- Cosyntropin test: Marked ↑17-hydroxypregnenolone & DHEA, no ↑17-hydroxyprogesterone & androstenedione.
- 21-Hydroxylase Deficiency
- Most common cause of CAH (90+%).
- Laboratory: ↑Progesterone, ↑17-hydroxyprogesterone, ↑androstenedione (all rise further with ACTH stimulation).
- Clinically presents with hirsutism, oligomenorrhea, ± mild virilization.
- 11β-Hydroxylase Deficiency
- Laboratory: ↑11-deoxycortisol, ↑11-deoxycorticosterone, ↑DHEA, ↑androstenedione.
- May have hypertension, hypokalemia (DOC’s mineralocorticoid effect), androgen excess → hirsutism.
- Treatment
- Glucocorticoid replacement to suppress ACTH and reduce adrenal androgen production.
- Care to avoid iatrogenic Cushing syndrome from overtreatment.
FAMILIAL GLUCOCORTICOID RESISTANCE
- Pathophysiology
- Mutations in the glucocorticoid receptor gene → decreased cortisol action → ↑ACTH → bilateral adrenal hyperplasia → excess androgens & mineralocorticoid-like steroids (11-deoxycorticosterone).
- Clinical
- Similar to partial 11β-hydroxylase deficiency: androgen excess plus HTN, hypokalemia.
ACTH-DEPENDENT CUSHING SYNDROME
- Mechanism
- High ACTH → adrenal hyperplasia → overproduction of cortisol and adrenal androgens.
- Clinical
- Women: Combined features of Cushing’s (central obesity, striae, etc.) plus hirsutism/virilization.
ANDROGEN-SECRETING ADRENAL NEOPLASMS
- Incidence
- Rare. More frequent in adrenocortical carcinoma than benign adenoma.
- Hormonal Output
- Typically DHEA, often androstenedione or testosterone.
- Imaging
- Carcinomas: Usually large (>4 cm), inhomogeneous, high CT density.
- Adenomas: Small (<3 cm), homogeneous, lower CT density.
THE BIOLOGIC ACTIONS OF ADRENAL ANDROGENS
- Major Adrenal Androgens: DHEA, DHEA-S, androstenedione, testosterone.
- Women: Adrenal androgens are the primary source of androgens.
- Men: Testicular testosterone usually dominates.
- Physiologic Roles
- Anabolic effects → muscle mass increase.
- Male secondary sex traits (facial hair, deep voice, etc.).
- In women, adrenal androgens are crucial for axillary/pubic hair; deficiency leads to hair loss in these areas.
- Adrenarche vs. Pubarche
- Adrenarche: Biochemical event, ↑adrenal androgens at ~6–8 yrs.
- Pubarche: Phenotypic event, sexual hair growth in pubic & axillary areas.
- Premature: Pubarche <8 yrs in girls, <9 yrs in boys = advanced hair growth, possibly advanced bone age.
- Conversion and Metabolism
- DHEA-S acts as a large reservoir → converted to DHEA → androstenedione → testosterone or estradiol in peripheral tissues.
- Possibly a neurosteroid role in brain, though no definitive DHEA receptor identified.
- Anabolic Steroid Use in Athletes
- Often used illicitly to increase muscle mass, enhance performance.
- Negative effects: testicular suppression (↓fertility), gynecomastia, liver damage, mood disorders (“roid rage”), dyslipidemia, virilization in women, stunted growth in adolescents.