Adolescent Gyn Flashcards
the Van Wyk–Grumbach syndrome
hypothyroidism associated with precocious puberty is caused by primary thyroid insufficiency, usually Hashimoto thyroiditis. The pathophysiology of this syndrome is a result of the diminished negative feedback of thyroxine, resulting in an increased production of TSH, which may be accompanied by an increase in production of gonadotropins. Another possible mechanism is the stimulation of the FSH receptor by high levels of TSH.
the only cause of precocious puberty in which the bone age is retarded is…
hypothyroidism, This syndrome is usually observed in girls between the ages of 6 and 8 years.
The most common cause of pseudo or feminizing precocious puberty is
an estrogen-secreting ovarian cyst or large functioning follicle.
the most common type of solid ovarian tumor resulting in precocious puberty is
Granulosa cell tumors These tumors are usually larger than 8 cm in diameter when associated with precocious puberty; 80% can be palpated abdominally.
Other ovarian tumors that may be associated with precocious puberty include thecomas, luteomas, teratomas, Sertoli-Leydig tumors, choriocarcinomas, and benign follicular cysts.
rare condition caused by a mutation in the G3 protein leading to activation of adenylate cyclase
McCune-Albright syndrome (MAS)
Clinically there is a triad of café-au-lait spots, polyostotic fibrous dysplasia, and cysts of the skull and long bones
Approach to precocious puberty
meticulous history and physical examination. Must rule out life-threatening neoplasms of the ovary, adrenal gland, or CNS by a series of tests, including neurologic and ophthalmologic examinations, EEGs, and brain imaging. Then delineate the speed of the maturation process, Tanner stage, Ultrasound, CT, or MRI of the abdomen and pelvis should be performed to evaluate enlargement of the ovaries (ovarian volume), uterus, or adrenal glands.
Serum levels of FSH, LH, prolactin, TSH, E2, testosterone, DHEA-S, hCG, androstenedione, 17-hydroxyprogesterone, tri- iodothyronine (T3), and thyroxine (T4) may be of value in establishing the differential diagnosis.
A GnRH agonist stimulation test is diagnostic in differentiating incomplete from true precocious puberty.
Labial adhesions literally mean the labia minora have adhered or agglutinated together at the midline. Another term sometimes used to describe this condition is
adhesive vulvitis
Labial adhesion treatment
Topical estrogen twice per day Care should be taken to not prolong the topical use of estrogen for more than 6 to 8 weeks. Prolonged use of topical estrogen has been associated with breast budding and in some less common cases vaginal bleeding from the peripheral effects of the absorption of estrogen. Failure of separation within the normal time frame should trigger alternate treatment. When patients fail estrogen therapy, and symptoms persist, the use of topical corticosteroids twice a day for 6 to 8 weeks. Once the condition has been resolved, recurrence can often be prevented by applying a bland ointment (such as zinc oxide cream or petroleum jelly) to the raw epithelial edges for at least 1 month or even longer.
Labial adhesion ddx
the combination of labial adhesions and scarring of the posterior fourchette, especially in children with new-onset labial adhesions after age 6, should prompt the clinician to consider sexual abuse in the differential diagnosis.
Differential Diagnosis of Prepubertal Bleeding without Any Breast Development
Foreign object-Genital trauma-Sexual abuse - Lichen sclerosus - Infectious vaginitis (especially Shigella) - Urethral prolapse - Breakdown of labial adhesions - Friable genital warts or vulvar lesions - Vaginal tumor (sarcoma botryoides and endodermal sinus tumors of the vagina) - Rare presentation of McCune-Albright syndrome (typically have breast development) - Isolated menarche (controversial) - Dermatologic conditions with secondary excoriation - Nongenital bleeding; mistaken as genital: rectal and urinary
the definition of precocious development or puberty (PROS new guideline)
Was defined as early breast development, early pubic hair development, or both with menses before age 8 years. Because of earlier pubertal milestones among different ethnicities,some recommend to define it as
thelarche or adrenarche prior to age 6 in African-American girls or 7 in white girls. (Controversial)
McCune-Albright Syndrome affected gene
GNAS1, somatic mutation that occurs during embryogenesis in neural crest cells affects G protein receptors and has a variable expression
Classic triad of McCune-Albright Syndrome
café-au-lait spots, abnormal bone lesions, and endocrinopathy most commonly precocious puberty due to overfunction of the ovary (peripheral)
But The presence of higher levels of sex steroids in peripheral precocious puberty may cause the activation of the hypothalamic–pituitaryovarian axis and the patient may develop central precocious puberty.
clitorimegaly
In children more than 1 cm
In adult more than 2.5 cm
Triad of ambiguous genitalia
- clitorimegaly >1cm
- partial or complete fused labia majora
- urethral and vaginal deformity (UGS)
The most common cause of central precocious puberty is
idiopathic (in greater than 50% of girls with central precocious puberty)
however, central nervous system lesions must be excluded like CNS tumors or anomaly or infection, Head trauma, lschemia, Iatrogenic: radiation, chemotherapy, surgical
Leuprolide stimulation test may help differentiate premature thelarche from true central and peripheral precocious puberty.
How is it done ?
Leuprolide (Lupron), which is an initial GnRH agonist, is given as a single intravenous dose of 20 µg/kg and does not to exceed a total dose of 500 µg. FSH plus LH levels are measured at 1, 2, and 3 hours. An estradiol level is measured at 24 hours. Central precocious puberty is confirmed by a rise in serum LH levels following infusion of the GnRH agonist.
In contrast, high estradiol levels and low gonadotropin levels during the stimulation test suggest peripheral precocious puberty