Clinical Approach—Preliminary Evaluation
• Are breasts present or absent? A physical examination will evaluate secondary sexualcharacteristics (breast development, axillary and pubic hair, growth). Breasts are an endogenous assay of estrogen. Presence of breasts indicates adequate estrogen pro-duction. Absence of breasts indicates inadequate estrogen exposure.
• Is a uterus present or absent? An ultrasound of the pelvis should be performed toassess presence of a normal uterus.
Table II-11-1. Müllerian Agenesis versus Androgen Insensitivity
| Breasts Present/Uterus Absent | Müllerian Agenesis | Androgen Insensitivity |
| (46,XX) | (46,XY) | |
| Uterus absent? | Idiopathic | MIF |
| Estrogen from? | Ovaries | Testes |
| Pubic hair? | Present | Absent |
| Testosterone level? | Female | Male |
| Treatment | No hormones | Estrogen |
| Create vagina | Create vagina | |
| IVF surrogate | Remove testes | |
Definition of abbreviations: MIF, Müllerian inhibitory factor.
Table II-11-2. Gonadal Dysgenesis versus HP Axis Failure
| Breasts Absent/Uterus Present | Gonadal | HP Axis |
| Dysgenesis | Failure | |
| (45,X) | (46,XX) | |
| FSH | ↑ | ↓ |
| Why no estrogen? | No ovarian follicles | Follicles not stimulated |
| Ovaries? | “Streak” | Normal |
| Treatment pregnancy | E + P | E + P |
| Egg donor | Induce ovulation (HMG) | |
| Diagnostic test? | CNS imaging | |
Definition of abbreviations: E + P, estrogen and progestin; HMG, human menopausal gonadotropin.
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USMLE Step 2 l Gynecology
GYN Triad
Müllerian Agenesis
• Primary amenorrhea
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• (+) breasts but (–) uterus
• (+) pubic and axillary hair
GYN Triad
Androgen Insensitivity
43Primary amenorrhea
44 (+) breasts but (–) uterus
45 (–) pubic and axillary hair
GYN Triad
Gonadal Dysgenesis
• Primary amenorrhea
• (–) breasts but (+) uterus
• ↑ FSH levels
GYN Triad
Hypothalamic–Pituitary
Failure
• Primary amenorrhea
• (–) breasts but (+) uterus
• ↓ FSH levels
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Clinical Approach Based on Findings Regarding Breasts and Uterus
• Breasts present, uterus present. Differential diagnosis includes an imperforate hymen,vaginal septum, anorexia nervosa, excessive exercise, and possible pregnancy before first menses.
– History and physical examination will identify the majority of specific diagnoses.
– Otherwise the workup should proceed as if for secondary amenorrhea.
• Breasts present, uterus absent. Differential diagnosis is Müllerian agenesis (Rokitansky-Kuster-Hauser syndrome) and complete androgen insensitivity (testicular feminization). Testosterone levels and karyotype help make the diagnosis.
– Müllerian agenesis. These are genetically normal females (46,XX) with idiopathic absence of the Müllerian duct derivatives: fallopian tubes, uterus, cervix, and upper vagina; the lower vagina originates from the urogenital sinus.
Patients develop secondary sexual characteristics because ovarian function is intact; Müllerian ducts do not give rise to the ovaries.
Normal pubic and axillary hair is present. Testosterone levels are normal female.
Management: surgical elongation of the vagina for satisfactory sexual intercourse
– Androgen insensitivity. In these genetically male (46,XY) individuals with complete lack of androgen receptor function, their bodies do not respond to the high levels of androgens present.
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Without androgen stimulation, internal Wolffian duct structures atrophy. With testicular Müllerian inhibitory factor present, the Müllerian duct derivatives involute.
Without body recognition of dihydrotestosterone, external genitalia differentiate in a female direction. Patients function psychologically and physically as females and are brought up as girls. At puberty, when primary amenorrhea is noted, the diagnosis is made.
Female secondary sexual characteristics are present because the testes do secrete estrogens without competition from androgens. No pubic or axillary hair is noted. Testosterone levels are normal male.
Management: testes removal at age 20 because the higher temperatures associ-ated with the intraabdominal position of the testes may lead to testicular cancer. Estrogen replacement is then needed.
• Breasts absent, uterus present. Differential diagnosis is gonadal dysgenesis (Turnersyndrome) and hypothalamic–pituitary failure. FSH level and karyotype help make the diagnosis.
– Gonadal dysgenesis. Turner syndrome (45,X) is caused by the lack of one X chro-mosome, essential for the presence of normal ovarian follicles. Instead of devel-oping ovaries, patients develop streak gonads. FSH is elevated because of lack of estrogen feedback to the hypothalamus and pituitary. No secondary sexual charac-teristics are noted.
Management: Estrogen and progesterone replacement for development of the sec-ondary sexual characteristics
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Chapter 11 l Menstrual Abnormalities
| – Hypothalamic–pituitary failure. In the patient without secondary sexual charac- | GYN Triad | |||||
| teristic but uterus present by ultrasound, another possibility is the hypothalamic | ||||||
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| Kallmann Syndrome | |||||
| causes of amenorrhea (stress, anxiety, anorexia nervosa, excessive exercise). FSH | ||||||
| will be low. Kallman syndrome is the inability of the hypothalamus to produce | • Primary amenorrhea
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| GnRH and also anosmia. The defect is in the area of the brain that produces | • (–) breasts but (+) uterus | |||||
| GnRH, but it’s also close to the olfactory center. CNS imaging will rule out a | ||||||
| • Anosmia | ||||||
| brain tumor. | ||||||
| – Management: These patients should be treated with estrogen and progesterone | ||||||
| replacement for development of the secondary sexual characteristics. | ||||||
SECONDARY AMENORRHEA
A 32-year-old woman states that her last menstrual period was 1 year ago. She started menses at age 12, and was irregular for the first couple of years, but since age
14 or 15 she had menstruated every 28–29 days. She has not been pregnant and is concerned about the amenorrhea. She has not been sexually active and has not used contraception. She has no other significant personal or family history. Physical examination, including a pelvic exam, is normal.
Definition. Amenorrhea means absence of menstrual bleeding. Secondary means that previ-ously menstrual bleeding had occurred.
Diagnosis. Secondary amenorrhea is diagnosed with absence of menses for 3 months if previ-ously regular menses or 6 months if previously irregular menses.
Pathophysiology. There are multiple etiologies for secondary amenorrhea, which can be classi-fied by alterations in FSH and LH levels. They include hypogonadotropic (suggesting hypotha-lamic or pituitary dysfunction), hypergonadotropic (suggesting ovarian follicular failure), and eugonadotropic (suggesting pregnancy, anovulation, or uterine or outflow tract pathology).
Specific etiology.
• Pregnancy. The first step is ab-hCG to diagnose pregnancy. This is the most commoncause of secondary amenorrhea.
• Anovulation. If no corpus luteum is present to produce progesterone, there can be noprogesterone-withdrawal bleeding. Therefore, anovulation is associated with unopposed estrogen stimulation of the endometrium. Initially the anovulatory patient will dem-onstrate amenorrhea, but as endometrial hyperplasia develops, irregular, unpredictable bleeding will occur. The causes of anovulation are multiple, including PCOS, hypothy-roidism, pituitary adenoma, elevated prolactin, and medications (e.g., antidepressants).
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GYN Triad
Anovulatory Bleeding (Physiologic)
• Irregular, unpredictable vaginal bleeding
• 13-year-old adolescent
• Normal height and weight
GYN Triad
Anovulatory Bleeding (Chronic)
• Irregular, unpredictable vaginal bleeding
• 33-year-old woman
• Obese, hypertensive
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• Estrogen Deficiency. Without adequate estrogen priming the endometrium will beatrophic with no proliferative changes taking place. The causes of hypoestrogenic states are multiple, including absence of functional ovarian follicles or hypothalamic– pituitary insufficiency.
• Outflow Tract Obstruction. Even with adequate estrogen stimulation and progester-one withdrawal, menstrual flow will not occur if the endometrial cavity is obliterated or stenosis of the lower reproductive tract is present.
Management
Pregnancy Test. The first step in management of secondary amenorrhea is to obtain aqualitative b-hCG test to rule out pregnancy.
Thyrotropin (TSH) Level. If theb-hCG test is negative, hypothyroidism should be ruledout (TSH level). The elevated thyrotropin-releasing hormone (TRH) in primary hypo-thyroidism can lead to an elevated prolactin. If hypothyroidism is found, treatment is thyroid replacement with rapid restoration of menstruation.
Prolactin Level
• Medications. An elevated prolactin level may be secondary to antipsychotic medi-cations or antidepressants, which have an anti-dopamine side effect (it is known that the hypothalamic prolactin-inhibiting factor is dopamine).
• Tumor. A pituitary tumor should be ruled out with CT scan or MRI of the brain.If a pituitary tumor is found and is <1 cm in its greatest dimension, treat medically with bromocriptine (Parlodel), a dopamine agonist. If >1 cm, treat surgically.
• Idiopathic. If the cause of elevated prolactin is idiopathic, treatment is medical with
bromocriptine.
Progesterone Challenge Test (PCT). If theb-hCG is negative, and TSH and prolactinlevels are normal, administer either a single IM dose of progesterone or 7 days of oral medroxyprogesterone acetate (MPA).
• Positive PCT. Any degree of withdrawal bleeding is diagnostic of anovulation.Cyclic MPA is required to prevent endometrial hyperplasia. Clomiphene ovulation induction will be required if pregnancy is desired.
• Negative PCT. Absence of withdrawal bleeding is caused by either inadequateestrogen priming of the endometrium or outflow tract obstruction.
Estrogen–Progesterone Challenge Test (EPCT). If the PCT is negative, administer 21days of oral estrogen followed by 7 days of MPA.
• Positive EPCT. Any degree of withdrawal bleeding is diagnostic of inadequate estro-gen. An FSH level will help identify the etiology.
– Elevated FSH suggests ovarian failure. If this occurs age <25, the cause could be Y chromosome mosaicism associated with malignancy, so order a karyotype.
Savage syndrome or resistant ovary syndrome is a condition in which follicles areseen in the ovary by sonogram, though they do not respond to gonadotropins.
– Low FSH suggests hypothalamic–pituitary insufficiency. Order a CNS imag-ing study to rule out a brain tumor. Whatever the result, women with a posi-tive EPCT will need estrogen-replacement therapy to prevent osteoporosis and estrogen-deficiency morbidity. Cyclic progestins are also required to prevent endometrial hyperplasia.
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• Negative EPCT. Absence of withdrawal bleeding is diagnostic of either an outflowtract obstruction or endometrial scarring (e.g., Asherman syndrome). A hys-terosalpingogram (HSG) will identify where the lesion is. Asherman is the result of extensive uterine curettage and infection-produced adhesions. It is treated by hysteroscopic adhesion lysis followed by estrogen stimulation of the endometrium. An inflatable stent is then placed into the uterine cavity to prevent re-adhesion of the uterine walls.
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Hormonal Disorders 12
PRECOCIOUS PUBERTY
A 6-year-old girl is brought to the office by her mother who has noticed breast budding and pubic hair development on her daughter. She has also experienced menstrual bleeding. Her childhood history is unremarkable until 3 months ago when these changes began.
Diagnosis. Criteria for diagnosis include development of female secondary sexual characteris-tics and accelerated growth before age 8 in girls and age 9 in boys. Precocious puberty is more common in girls than boys.
Normal Pubertal Landmarks. Complete puberty is characterized by the occurrence of allpubertal changes.
• The most common initial change is thelarche (breast development at age 9–10).
• This is followed by adrenarche (pubic and axillary hair at age 10–11).
• Maximal growth rate occurs age 11 and 12.
• Finally, the last change is menarche (onset of menses at age 12–13).
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