The precocious puberty marks the beginning of sexual maturation before age 8 in girls and before 9 in boys. The diagnosis is made by comparing with population standards, X-rays of the left hand and wrist (for assessing skeletal maturity and identifying a more rapid bone growth) and by determination of gonadotropins, gonadal steroids and adrenal steroids. Treatment depends on the cause.
In girls, the first pubeszente milestone is typically the breast development (thelarche), soon followed by the pubic hair (pubarche) and underarm hair, and later from the first period (menarche), which traditionally occurs 2 to 3 years after the thelarche (puberty – Development of female sex characteristics.).
The precocious puberty marks the beginning of sexual maturation before age 8 in girls and before 9 in boys. The diagnosis is made by comparing with population standards, X-rays of the left hand and wrist (for assessing skeletal maturity and identifying a more rapid bone growth) and by determination of gonadotropins, gonadal steroids and adrenal steroids. Treatment depends on the cause. In girls, the first pubeszente milestone is typically the breast development (thelarche), soon followed by the pubic hair (pubarche) and underarm hair, and later from the first period (menarche), which traditionally occurs 2 to 3 years after the thelarche (puberty – Development of female sex characteristics.). In boys, the first pubeszente milestone is typically the testicular growth, followed by penile growth and the appearance of pubic and underarm hair (puberty when develop male sexual characteristics.). In both sexes, the appearance of pubic hair and underarm hair is called Adrenarche. The Adrenarche can occur in about 10% of children from the Gonadarche (premature Adrenarche). Although Gonadarche Adrenarche and may have overlapping characters, they are independently controlled. Since the beginning in the US must be applied earlier obviously, especially in girls, these traditional standards are being redefined. The definition of precocious puberty depends on a reliable population statistics for the onset of puberty from (z. B. when the pubeszenten milestones occur). The breast development occurs increasingly in younger age groups and this trend reflects the obesity epidemic by a higher body mass index (> 85th percentile) with a previous thelarche associated. In about 8-10% of fair-skinned girl, 20-30% of dark-skinned girl and an intermediate number of Hispanic girls, early puberty age of 8 can be observed. The lower limit of normal puberty may be at 6 years in fair-skinned girl at 7 years and in dark-skinned girl. The average age for breast development is (range: 8-13 years) about 9.5 to 10 years for light-skinned girls and 8.5-9 years for dark-skinned girl. However, age of menarche not dropped so dramatically, with an average decrease of only 3 months in the last 30 years (average age 11.5 years among black girls and 12.5 years for fair-skinned girls). The mean age for the growth of pubic hair is for both groups 9-10.5 years. These findings suggest that the guideline for the evaluation of diseases that can cause precocious puberty one, in children who are otherwise healthy and reach their full adult size, should be judged more leniently. Classification Precocious puberty may be divided into 2 types: gonadotropin-releasing hormone (GnRH) -dependent (central precocious puberty) GnRH-independent (peripheral sex hormone effects) The GnRH-dependent precocious puberty is generally more frequent and 5 to 10 times more common in Girl. the hypothalamic-pituitary axis is praecox in the GnRH-dependent puberty activated and leads to an increase and maturation of the gonads, the development of secondary sexual characteristics and the spermatogenesis or oogenesis. The precocious puberty GnRH-independent is much less frequent. The secondary sexual characteristics develop due to high circulating levels of estrogen and androgen levels without activation of the hypothalamic-pituitary axis. The precocious puberty can be classified according to whether one or Gonadarche Adrenarche occurs. In girls, the Gonadarche includes breast growth, a change in body status, growth of the uterus and finally a menarche. In boys, the Gonadarche consists of a testicular growth, penis growth, the first appearance of pubic hair, face and underarm hair, altered body odor and oily facial skin and acne. Adrenarche for girls and boys includes the development of body hair, body odor and acne. An incomplete or not persistent pubertal development is often, most commonly as isolated premature thelarche or Adrenarche. Girl with premature thelarche typically exhibit during the first 2 years of life breast development, but this change is not accompanied by pubertal hormone levels, menarche, advanced age on bone radiographs, androgen effects or acceleration of growth. An isolated early Adrenarche is also not connected to a progressive pubertal development. Children with early Adrenarche may have signs of adrenal androgen production (eg. As pubic hair, acne, body odor), which progresses slowly without acceleration of linear growth. Premature Adrenarche can ((polycystic ovarian syndrome PCOS)) with the later development of polycystic ovary syndrome may be associated in adolescence. Etiology GnRH-dependent precocious puberty, the physical changes are typically those of normal puberty for a child of this generation, except for the age of onset. For most affected girls no specific cause can be identified. In the absence of specific symptoms or signs of CNS disorders, the probability of intracranial abnormality depends on a younger age at onset of puberty (<4 years in girls) and the sex of the child (more common in boys) from. Overall, affected boys are more likely to have (up to 60%) an identifiable underlying disorder. These causes include intracranial tumors, especially tumors of the hypothalamus and the pineal gland tumors, including hamartomas, gliomas, Germinomas and adenomas, one. The neurofibromatosis and other rare diseases could be precocious puberty with a linked. The central precocious puberty may also consist of iatrogenic causes (eg. As surgery, radiation or chemotherapy for cancer) hervorgehen.GnRH-independent precocious puberty The etiology depends on the prevailing sex hormone effect (estrogen or androgen), and the physical changes are often significantly discordant from normal pubertal development. Estrogenic effects are most commonly caused by follicular ovarian cysts; other causes include granulosa and McCune-Albright syndrome, a (a triad of follicular cysts, polycystic, fibrous dysplasia and cafe-au-lait spots). Adrenal enzyme defects, in particular congenital adrenal hyperplasia (overview of congenital adrenal hyperplasia), the most common pathological form of Androgenexzesses in children of both sexes. Additional causes of GnRH-independent precocious puberty in boys include familial male gonadotropin-independent precocious puberty (due to an activated mutation of a gene for the LH receptor), testosterone-producing testicular tumors and occasionally McCune-Albright syndrome one. Symptoms and signs In girls, the breast and pubic hair, underarm hair, or both developed. Girls may begin to menstruate. In boys, the facial, underarm and pubic hair appears and the penis grows depending on the etiology, with or without enlargement of the testicles. Body odor, acne and behavioral changes can develop in both sexes. Adolescent size growth occurs in both sexes on (early to middle puberty in girls, middle to late puberty in boys), but a premature closure of the epiphyses leads to dwarfism. Ovarian or testicular enlargement is common in precocious puberty, but is rare in the isolated early Adrenarche. Diagnostic bone age X-rays hormonal status in serum may pelvic ultrasonography and magnetic resonance imaging of the brain is diagnosed clinically. Radiographs of the left hand and wrist are made to evaluate an accelerated bone growth as a cause of the sex hormone effect. Unless history and examination suggest an anomaly, no further clarification for children with pubeszenten milestones necessary located within the average values ??of the population. Girls and boys with isolated precocious Adrenarche and girls with precocious thelarche require also require no further clarification, as long as the X-rays show that the skeletal maturation is not accelerated. If a further evaluation is necessary blood tests according to the present characteristics should be selected. For patients who have especially androgenic effects, the most useful initial tests include measurements of total testosterone, dehydroepiandrosterone-sulfate, 17-hydroxyprogesterone, and luteinizing hormone (LH); should all be measured with highly sensitive tests that were designed for pediatric patients. For patients who only have estrogenic effects, the most useful screening for girls include ultra-sensitive LH and follicle stimulating hormone (FSH) and estradiol and for boys LH, FSH, ?-chorionic gonadotropin and estradiol. Pelvic and adrenal ultrasonography can be useful if one of the steroid levels are elevated, and an MRI of the brain can be performed to exclude intracranial abnormalities in younger patients or in boys with central precocious puberty. A GnRH stimulation test may be considered to confirm a GnRH-dependent precocious puberty if initial tests are inconclusive. Formerly a one-hour stimulation test with GnRH agonists gonadorelin was used, but because gonadorelin is no longer available, other GnRH agonists, such as leuprolide are used. Leuprolide acetate 10 to 20 mcg / kg s.c. is administered and LH, FSH, testosterone (boys) and estradiol (in girls) at 0, 1, and measured for 2 h. At 24 hours post-leuprolide, estradiol and testosterone can be measured in order to improve the sensitivity of the test. gonadotropin responses are praecox at GnRH-dependent puberty adolescent. gonadotropin responses to leuprolide are praecox at GnRH-independent precocious puberty prepubertal. Treatment GnRH agonist therapy (GnRH-dependent precocious puberty) androgen or estrogen antagonists (GnRH-independent precocious puberty) tumor removal as needed, if the pubeszenten milestones differ by only up to one year from the general population standards, submit a new protection and regular studies from. Early Adrenarche or thelarche do not have to be treated but a regular examination is necessary to control the subsequent development of early puberty. In the GnRH-dependent precocious puberty the LH and FSH secretion can be suppressed by GnRH agonists, including leuprolide acetate 7.5 to 15 mg i.m. every 4 weeks or 11.25 mg or 30 mg i.m. every 12 weeks or Histrelinimplantate (changed annually). The response to treatment must be monitored and the dosage adjusted accordingly. The treatment can be continued until the age of 11 years in girls and up to 12 years of age in boys. In girls with McCune-Albright syndrome are aromatase inhibitors, including older drugs such as testolactone and newer medications such as letrozole and anastrozole, has been studied with varying success for the reduction of estradiol; alternatively, tamoxifen, an estrogen antagonist, be useful. When a GnRH-independent puberty in boys is present due to a familial male gonadotropin-independent precocious puberty or McCune-Albright syndrome, androgen antagonists can improve the effect of excess androgen such as spironolactone. Fungicides such as ketoconazole reduce the testosterone level in boys with familial male gonadotropin-independent precocious puberty. If a GnRH-independent precocious puberty due to a hormone-producing tumor is present (granulosa in girls, testicular cancer in boys), such a tumor should be removed. Girls, however, should be regularly tested for contralateral recurrence. Important points Precocious puberty is the beginning of puberty before the age of 8 years in girls and before age 9 years in boys; However, puberty started earlier in recent years, and traditional standards are revised. Most commonly, the secondary sexual characteristics develop too early because the hypothalamic-pituitary axis is enabled (GnRH-dependent precocious puberty); often the cause is idiopathic, but some children have a central nervous system tumor. Less frequently are the cause of high blood levels of estrogens or androgens (GnRH-independent precocious puberty) caused by congenital adrenal hyperplasia or different gonadal tumors. The diagnosis is made by performing X-ray bone age and hormone levels are measured. GnRH-dependent precocious puberty is treated with the GnRH agonist leuprolide or histrelin. GnRH-independent precocious puberty is treated based on the cause, including the administration of androgen or estrogen antagonist and the removal of tumors.