Congenital Adrenal Hyperplasia (21-Hydroxylase Deficiency)
• History. Typically the onset has been gradual in the second or early third decade oflife and is associated with menstrual irregularities and anovulation. Precocious puber-ty with short stature is common. Family history may be positive. Late-onset CAH is one of the most common autosomal recessive genetic disorders.
• Examination. Physical examination will show evidence of hirsutism without viriliza-tion. Pelvic examination is unremarkable.
• Laboratory tests. Serum 17-OH progesterone level is markedly elevated.
• Management. Treatment is medical with continuous corticosteroid replacement,which will arrest the signs of androgenicity and restore ovulatory cycles.
GYN Triad
Ovarian Tumor (Sertoli-
Leydig)
• Abrupt-onset virilization
• Pelvic mass
• ↑↑ testosterone levels
GYN Triad
Congenital Adrenal
Hyperplasia 21-OH
Deficiency
• Gradual-onset hirsutism
• Normal exam
• ↑ 17-OH progesterone
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| Cortisol |
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| Figure II-12-6. Normal Adrenal Function | Figure II-12-7. Adrenal Hyperplasia | |||||||||||||||||||||||||
Polycystic Ovarian Syndrome (PCOS)
• History. Typically the onset has been gradual, frequently with a positive family history.In addition, the history is positive for irregular bleeding and infertility.
• Examination. Physical examination usually reveals hirsutism often with obesity andincreased acne. Bilaterally enlarged, smooth, mobile ovaries will be palpated on pelvic examination. Acanthosis nigricans may be seen.
• Laboratory tests. Testosterone level is mildly elevated. LH to FSH ratio is elevated(3:1). Sex hormone binding globulin (SHBG) is decreased.
• Imaging. Pelvic ultrasound will show bilaterally enlarged ovaries with multiple sub-capsular small follicles and increased stromal echogenicity.
• Management. The treatment of choice is combination OCPs. They will lower free tes-tosterone levels in 2 ways. First, OCPs will lower testosterone production by suppress-ing LH stimulation of the ovarian follicle theca cells. Second, OCPs will also increase SHBG, thus decreasing free testosterone level. Metformin can decrease insulin resis-tance and lower testosterone levels.
GYN Triad
Idiopathic (Hair Follicle)
↑ 5-α Reductase Activity
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• Gradual-onset hirsutism
• Normal exam
• Normal DHEAS, testosterone, 17-OH progesterone
Idiopathic
• History. Typically the onset has been gradual, frequently with a positive family his-tory. Menses and fertility are normal. This is the most common cause of androgen excess in women.
• Examination. Physical examination reveals hirsutism without virilization. Pelvicexamination is normal.
• Laboratory tests. Normal levels of testosterone, DHEAS, and 17-OH progesterone areidentified.
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Chapter 12 l Hormonal Disorders
• Management. The treatment of choice is spironolactone, a potassium-sparingdiuretic. Its mechanism of action as an antiandrogen is twofold. First, it is an andro-gen-receptor blocker. It also suppresses hair follicle 5-α reductase enzyme conver-sion of androstenedione and testosterone to the more potent dihydrotestosterone. Eflornithine (Vaniqa) is the first topical drug for the treatment of unwanted facialand chin hair. It blocks ornithine decarboxylase (ODC), which slows the growth and differentiation of the cells within the hair follicles.
POLYCYSTIC OVARIAN SYNDROME
A 32-year-old woman visits the gynecologist’s office complaining of vaginal bleeding, facial hair growth, and obesity. She states that she has noted the facial hair growth for many years and the irregular bleeding has been progressively getting worse during the past 6 months. She has no other significant personal or family history, and on pelvic examination she has slightly enlarged bilateral ovaries. A rectovaginal examination is confirmatory.
Definition. Polycystic ovarian syndrome (PCOS), historically called Stein-Leventhal syndrome,is a condition of chronic anovulation with resultant infertility. The patient presents typically with irregular vaginal bleeding. Other symptoms include obesity and hirsutism.
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Pathophysiology
• Chronic anovulation. Instead of showing the characteristic hormone fluctuationof the normal menstrual cycle, PCOS gonadotropins and sex steroids are in a steady state, resulting in anovulation and infertility. Without ovulation, there is no corpus luteum to produce progesterone. Without progesterone there is unopposed estrogen.
Endometrium, which is chronically stimulated by estrogen, without progesterone ripening and cyclic shedding, becomes hyperplastic with irregular bleeding. With time endometrial hyperplasia can result, which could progress to endometrial cancer.
• Increased testosterone. Increased LH levels cause increased ovarian follicular thecacell production of androgens. The increased levels of androstenedione and testosterone suppress hepatic production of SHBG by 50%. The combined effect of increased total
testosterone and decreased SHBG leads to mildly elevated levels of free testosterone. This results in hirsutism. PCOS is one of the most common causes of hirsutism in women.
• Ovarian enlargement. On ultrasound the ovaries demonstrate the presence of thenecklacelike pattern of multiple peripheral cysts (20–100 cystic follicles in each ovary). The increased androgens prevent normal follicular development, inducing premature follicle atresia. These multiple follicles, in various stages of development and atresia, along with stromal hyperplasia and a thickened ovarian capsule, result in ovaries that are bilaterally enlarged.
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