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51-563: One Small Voice Foundation is a non-profit foundation which finances research into the medical disorders of optic nerve hypoplasia and hydrocephalus . It was founded by Deborah and Kevin Katzbeck after the birth of their hydrocephalic child in 2000. This article about a United States health organization is a stub . You can help Misplaced Pages by expanding it . Optic nerve hypoplasia ONH may be found in isolation or in conjunction with myriad functional and anatomic abnormalities of

102-585: A 9-year-old boy suggest a pineal gland tumor. The tumor is called a chorionic gonadotropin secreting pineal tumor . Radiotherapy and chemotherapy reduced tumor and beta-hCG levels normalized. In a study using neonatal melatonin on rats, results suggest that elevated melatonin could be responsible for some cases of early puberty. Familial cases of idiopathic central precocious puberty (ICPP) have been reported, leading researchers to believe there are specific genetic modulators of ICPP. Mutations in genes such as LIN28 , and LEP and LEPR, which encode leptin and

153-406: A clinically useful measurement to help diagnose optic nerve hypoplasia. Where "DM" represents the distance from Disk to Macula, and "DD" represents Disc Diameter. The mean disc diameter (DD) is (Vertical diameter of Disc+Horizontal diameter of Disc) divided by 2. The distance between the center of the disc and the macula is DM. Interpretation: When the ratio of DM to DD is greater than 3, ONH

204-405: A lack of thyroid hormone, leading to central hypothyroidism. Thyroid hormone is critical for growth and brain development, especially during the first few weeks to months of life. Children with untreated hypothyroidism are at high risk of mental retardation; thus, early detection is crucial. Central hypothyroidism can be diagnosed by a low or normal thyroid-stimulating hormone (TSH) in the presence of

255-602: A low level of free T4. Free T-4 should be checked annually for at least four years. Cortisol is made in times of stress. Approximately one-quarter of patients with ONH have adrenal insufficiency, meaning they do not produce enough cortisol on a daily basis or in stressful situations. Imbalances in sex hormone may result in a delay in sexual development (puberty) or precocious puberty . Sex hormones may be tested from birth to 6 months of age (during mini-puberty ). Hyperprolactinemia (an excess of prolactin) often occurs in conjunction with ONH and indicates either dysfunction of

306-585: A minority of children with precocious puberty, the early development is triggered by a disease such as a tumor or injury of the brain . Even when there is no underlying disease, unusually early puberty can have adverse effects on social behavior and psychological development (having more mature knowledge than one's peers, feeling inadequate, trying to attend and establish friendships with older people, depression ). Affected children also face shorter adult height potential and possible lifelong health risks. Central precocious puberty can be treated by suppressing

357-433: A result, "early puberty" in children as young as 8 and 9 is no longer considered abnormal, particularly with girls. Although it is not considered as abnormal, it may be upsetting to parents and can be harmful to children who mature physically at a time when they are immature mentally. No age reliably separates normal from abnormal processes in children, but the following age thresholds for evaluation are thought to minimize

408-498: A role in human bonding, increase in trust, and decrease in fear. Hypothalamic dysfunction may also result in problems with feeding, sleep, and body temperature regulation. Feeding behaviors in children with ONH often include hyperphagia (overeating), resulting in obesity; or hypophagia (reduced food intake) with or without weight loss. Children also frequently experience aversion to specific textures of food. Disturbance of circadian sleep rhythm , resulting in abnormal sleep-wake cycles,

459-699: A term that refers to agenesis of the septum pellucidum. It is now clear that the absence of the septum pellucidum does not correlate with the associated symptoms of ONH. Dysfunction of the hypothalamus results in loss of regulation over behavior and function of the pituitary gland (master gland). Hypopituitarism is present in 75% to 80% of patients with ONH. The anterior pituitary gland contributes to growth, metabolism, and sexual development. The most common pituitary endocrinopathies are growth hormone (GH) deficiency (70%), hypothyroidism (43%), adrenal insufficiency (27%), and diabetes insipidus (5%). Absence of GH may often be indicated by short stature, although this

510-412: A very rare genetic condition called aromatase excess syndrome – in which exceptionally high circulating levels of estrogen are present – usually develop precocious puberty. Males and females are hyper-feminized by the syndrome. The "opposite" case would be the hyper-masculinisation of both male and female patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency , in which there

561-472: Is 10.9 per 100,000. Precocious puberty In medicine , precocious puberty is puberty occurring at an unusually early age. In most cases, the process is normal in every aspect except the unusually early age and simply represents a variation of normal development . There is early development of secondary sex characters and gametogenesis also starts earlier. Precocious puberty is of two types: true precocious puberty and pseudoprecocious puberty. In

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612-478: Is a congenital condition in which the optic nerve is underdeveloped (small). Many times, de Morsier’s Syndrome or septo-optic dysplasia (SOD) is associated with ONH, however, it is possible to have ONH without any additional issues like SOD. SOD is a condition that can involve multiple problems in the midline structures of the brain, stemming from miswiring of the brain and central nervous system. Besides having small optic nerves, persons with ONH can have agenesis of

663-641: Is an excess of androgens. Thus, in the aromatase excess syndrome the precocious puberty is isosexual in females and heterosexual in males, whilst in the CAH it is isosexual in males and heterosexual in females. Although the causes of early puberty are still somewhat unclear, girls who have a high-fat diet and are not physically active or are obese are more likely to physically mature earlier. "Obese girls, defined as at least 10 kilograms (22 pounds) overweight, had an 80 percent chance of developing breasts before their ninth birthday and starting menstruation before age 12 –

714-523: Is associated with advancement in bone age, which leads to early fusion of epiphyses, thus resulting in reduced final height and short stature. Adrenocortical oncocytomas are rare with mostly benign and nonfunctioning tumors. There have been only three cases of functioning adrenocortical oncocytoma that have been reported up until 2013. Children with adrenocortical oncocytomas will present with "premature pubarche, clitoromegaly, and increased serum dehydroepiandrosterone sulfate and testosterone" which are some of

765-399: Is being considered as a medical problem. Stricter definitions of "precocity" may refer only to central puberty starting before a statistically specified age based on percentile in the population (e.g., 2.5 standard deviations below the population mean), on expert recommendations of ages at which there is more than a negligible chance of discovering an abnormal cause, or based on opinion as to

816-443: Is called isosexual precocity. In some cases, a patient may develop characteristics of the opposite sex. For example, a male may develop breasts and other feminine characteristics, while a female may develop a deepened voice and facial hair. This is called heterosexual or contrasexual precocity. It is very rare in comparison to isosexual precocity and is usually the result of unusual circumstances. As an example, children with

867-413: Is considered idiopathic or constitutional. Secondary sexual development induced by sex steroids from other abnormal sources is referred to as peripheral precocious puberty or precocious pseudopuberty. It typically presents as a severe form of disease with children. Symptoms are usually as a sequelae from adrenal hyperplasia (because of 21-hydroxylase deficiency or 11-beta hydroxylase deficiency ,

918-407: Is not always the case. Other indicators of GH deficiency may include hypoglycemic events (including seizures), prolonged jaundice, micropenis in boys, and delayed dentition . Testing for GH may involve blood tests (IGF-1 and IGFBP-3), growth hormone stimulation test, or bone age x-ray of the hand or wrist (or body for children younger than 2 years). A poorly functioning pituitary gland may also cause

969-449: Is noted in one-third of children with ONH. This disturbance could result in behavioral problems and disruption of family life. More than 70% of children with ONH experience developmental delay, ranging from isolated focal defects to delay in all areas of development (global delay). Motor delay is most common (75%) and communication delay is least common (44%). Predictors of significantly delayed development include hypoplasia or agenesis of

1020-400: Is still some uncertainty surrounding the effectiveness of GnRHas when utilized for other conditions. Overall, puberty blockers have demonstrated an excellent safety and efficacy profile in the treatment of precocious puberty. The most common side effects reported include nonspecific headaches, hot flashes, and implant-related skin reactions. A systematic review of studies investigating

1071-630: Is suspected, and when it is greater than 4, Optic Nerve Hypoplasia is definite. There is no cure for ONH; however, many therapeutic interventions exist for the care of its symptoms. These may include hormone therapy for hypopituitarism, occupational , physical, and/or speech therapy for other issues, and services of a teacher for students with blindness/visually impairment. Special attention should be paid to early development of oral motor skills and acclimation to textured foods for children with texture aversion, or who are otherwise resistant to eating. Sleep dysfunction can be ameliorated using melatonin in

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1122-447: The corpus callosum , absence or incomplete development of the septum pellucidum , malformations of the pituitary gland, schizencephaly , cortical heterotopia , white matter hypoplasia, pachygyria , and holoprosencephaly . Hypoplasia of the corpus callosum, often in conjunction with other major malformations, is significantly associated with poor and delayed developmental outcome. ONH is often referred to as septo-optic dysplasia ,

1173-430: The pituitary hormones that induce sex steroid production. The opposite condition is delayed puberty . The term is used with several slightly different meanings that are usually apparent from the context. In its broadest sense, and often simplified as early puberty , "precocious puberty" sometimes refers to any physical sex hormone effect, due to any cause, occurring earlier than the usual age, especially when it

1224-644: The Lawson Wilkins Pediatric Endocrine Society and European Society for Pediatric Endocrinology published a consensus statement highlighting the effectiveness of Gonadotropin-releasing hormone analogs (GnRHas) in early onset central precocious puberty. They confirmed that the use of Gonadotropin-releasing hormone analogs (GnRHas) has had a positive effect on increasing adult height. However these Endocrine Societies believe additional research should be conducted before routinely suggesting GnRHAs for other conditions. There

1275-732: The age at which early puberty may have adverse effects. A common definition for medical purposes is onset before 8 years in girls or 9 years in boys. Early pubic hair , breast , or genital development may result from natural early maturation or from several other conditions. If the cause can be traced to the hypothalamus or pituitary , the cause is considered central. Other names for this type are complete or true precocious puberty. Causes of central precocious puberty can include: Central precocious puberty can also be caused by brain tumors , infection (most commonly tuberculous meningitis , especially in developing countries), trauma, hydrocephalus , and Angelman syndrome . Precocious puberty

1326-605: The age of three. Generally surgery results in improved appearance only and not in improved visual function. The visual prognosis in optic nerve hypoplasia is quite variable. Occasionally, optic nerve hypoplasia may be compatible with near-normal vision; in other cases, one or both eyes may be functionally, or legally blind . Although most patients with only optic nerve involvement lead normally productive lives, those with accompanying endocrine dysfunction or other midline cerebral abnormalities are more at risk for on-going intellectual and other disabilities. Optic nerve hypoplasia (ONH)

1377-401: The body from excessive urination. Testing for DI involves blood and urine testing, including water deprivation tests, to determine ADH creation levels by the body. DI may be treated with a medication called desmopressin acetate (DDAVP). Oxytocin is also produced in the posterior pituitary gland. Though best known for its role in childbirth and lactation, oxytocin has also been found to have

1428-454: The cause for ICPP However, this is still a controversial area of research, and some investigators found no association of mutations in the LIN28 and KISS1/KISS1R genes to be the common cause underlying ICPP. The gene MKRN3, which is a maternally imprinted gene, was first cloned by Jong et al. in 1999. MKRN3 was originally named Zinc finger protein 127. It is located on human chromosome 15 on

1479-612: The central nervous system. Nearly 80% of those affected with ONH will experience hypothalamic dysfunction and/or impaired development of the brain, regardless of MRI findings or severity of ONH. ONH can be unilateral (in one eye) or bilateral (in both eyes), though it presents most often bilaterally (80%). Unilateral cases tend to have better vision and are typically diagnosed at a later age than bilateral cases. Visual acuity can range from no light perception to near-normal vision. Children diagnosed with ONH generally present with vision problems which include nystagmus (involuntary movement of

1530-415: The corpus callosum , absence of the septum pellucidum , maldevelopment of the anterior and posterior pituitary gland , and anomalies of the hypothalamus . Because of this, all children with ONH are at risk for developmental delays and hormonal deficiencies, regardless of severity of ONH, or whether abnormalities are visible by MRI. ONH is the single leading cause of permanent legal blindness in children in

1581-553: The corpus callosum and hypothyroidism. The absence of the septum pellucidum does not predict developmental delay. Delays may occur in unilateral (39%) as well as bilateral (78%) cases. Mutations of genes involved in transcription regulation , chromatin remodelling , α-dystroglycan glycosylation , cytoskeleton and scaffolding protein , RNA splicing , and the MAP kinase signalling pathway are currently known to cause ONH. Many transcription factors for eye development are also involved in

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1632-433: The evening in order to adjust a child's circadian clock. Treatment for strabismus may include patching of the better eye, which may result in improved vision in the worse eye; however, this should be reserved for cases in which the potential for vision improvement in both eyes is felt to be good. Surgery to align the eyes can be performed once children with strabismus develop equal visual acuity in both eyes, most often after

1683-555: The eyes), which tends to develop at 1 to 3 months and/or strabismus (inability to align both eyes simultaneously), manifested during the first year of life. The majority of children affected experience improvement in vision during the first few years of life, though the reason for this occurrence is unknown. There have been no reported cases of decline in vision due to ONH. Estimates of cerebral malformations vary from 39% to 90% of children with ONH. Abnormalities evident via neuroradiography can include agenesis (absence) or hypoplasia of

1734-422: The former being more common), which includes but is not limited to hypertension, hypotension, electrolyte abnormalities, ambiguous genitalia in females, signs of virilization in females. Blood tests will typically reveal high level of androgens with low levels of cortisol. Causes can include: Generally, patients with precocious puberty develop phenotypically appropriate secondary sexual characteristics . This

1785-613: The higher prevalence of early puberty in black versus white girls." While more girls are increasingly entering puberty at younger ages, new research indicates that some boys are actually starting later ( delayed puberty ). "Increasing rates of obese and overweight children in the United States may be contributing to a later onset of puberty in boys, say researchers at the University of Michigan Health System." High levels of beta-hCG in serum and cerebrospinal fluid observed in

1836-399: The hypothalamus or a disconnect between the hypothalamus and pituitary gland. Hyperprolactinemia often correlates with development of obesity in children with ONH. The posterior pituitary gland produces anti-diuretic hormone (ADH), which controls outflow of water from the body by urine. ADH deficiency, also known as diabetes insipidus (DI), results in dehydration and high sodium levels in

1887-518: The leptin receptor, have been associated with precocious puberty. The association between LIN28 and puberty timing was validated experimentally in vivo, when it was found that mice with ectopic over-expression of LIN28 show an extended period of pre-pubertal growth and a significant delay in puberty onset. Mutations in the kisspeptin (KISS1) and its receptor, KISS1R (also known as GPR54), involved in GnRH secretion and puberty onset, are also thought to be

1938-533: The long arm in the Prader-Willi syndrome critical region2, and has since been identified as a cause of premature sexual development or CPP. The identification of mutations in MKRN3 leading to sporadic cases of CPP has been a significant contribution to better understanding the mechanism of puberty. MKRN3 appears to act as a "brake" on the central hypothalamic-pituitary access. Thus, loss of function mutations of

1989-651: The long-term effects of treating precocious puberty with GnRH agonists found that bone mineral density decreases during treatment but normalizes afterward, with no lasting effects on peak bone mass . Early puberty is posited to put girls at higher risk of sexual abuse ; however, a causal relationship is, as yet, inconclusive. Early puberty also puts girls at a higher risk for teasing or bullying, mental health disorders and short stature as adults. Girls as young as 8 are increasingly starting to menstruate , develop breasts and grow pubic and underarm hair; these "biological milestones" typically occurred only at 13 or older in

2040-487: The morphogenesis of forebrain, which may explain why ONH is commonly a part of a syndrome involving brain malformations. ONH impacts all ethnic groups, although in the United States, occurrence is lower in persons of Asian descent. To date, there have been few reports of ONH occurrence in Asian countries, although it is uncertain why this is so. Although many perinatal and prenatal risk factors for ONH have been suggested,

2091-723: The onset of puberty before 6 years of age; however there is variability in height outcomes across studies which can be attributed to varying study designs, time of symptom presentation, and time of treatment termination. A study investigating the effects of puberty blockers on reproductive health showed no significant difference in the number of irregular menstrual cycles, pregnancies, or pregnancy outcomes between women who received treatment for precocious puberty and those who opted out of treatment. Individuals with precocious puberty, early adrenarche, and early normal puberty show less stress after treatment compared to individuals without preexisting developmental conditions. Blockers are also used in

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2142-736: The past. African-American girls are especially prone to early puberty. Though boys face fewer problems from early puberty than girls do, early puberty is not always positive for boys. Early sexual maturation in boys can be accompanied by increased aggressiveness due to the surge of pubertal hormones. Because they appear older than their peers, pubescent boys may face increased social pressure to conform to adult norms; society may view them as more emotionally advanced, although their cognitive and social development may lag behind their physical development. Studies have shown that early-maturing boys are more likely to be sexually active and are more likely to participate in risky behaviors. Pubertas praecox

2193-499: The pituitary gland to release follicle stimulating hormone (FSH) and luteinizing hormone (LH). Triptorelin depot is widely used to treat central precocious puberty (CPP) in children. Puberty blockers work by stabilizing puberty symptoms, decreasing growth velocity, and slowing skeletal maturation. The outcomes of treatment are assessed in terms of height, reproduction, metabolic, and psychosocial measures. The most pronounced effects on height have been seen in children experiencing

2244-652: The predominant, enduring, most frequent risk factors are young maternal age and primiparity (the affected child being the first child born to the mother). Increased frequency of delivery by caesarean section and fetal/neonatal complications, preterm labor, gestational vaginal bleeding, low maternal weight gain, and weight loss during pregnancy are also associated with ONH. ONH is diagnosed by ophthalmoscopic examination. Patients with ONH exhibit an optic nerve that appears smaller than normal and different in appearance from small optic nerves caused by other eye conditions such as optic (nerve) atrophy. DM:DD ratio has proven to be

2295-567: The presentations associated with precocious puberty. Precocious puberty in girls begins before the age of 8. The youngest mother on record is Lina Medina , who gave birth at the age of either 5 years, 7 months and 17 days or 6 years 5 months as mentioned in another report. "Central precocious puberty (CPP) was reported in some patients with suprasellar arachnoid cysts (SAC), and SCFE ( slipped capital femoral epiphysis ) occurs in patients with CPP because of rapid growth and changes of growth hormone secretion." If no cause can be identified, it

2346-426: The protein allow early activation of the GnRH pathway and cause phenotypic CPP. Patients with a MKRN3 mutation all display the classic signs of CCP including early breast and testes development, increased bone aging and elevated hormone levels of GnRH and LH. Studies indicate that breast development in girls and the appearance of pubic hair in both girls and boys are starting earlier than in previous generations. As

2397-488: The risk of missing a significant medical problem: Medical evaluation is sometimes necessary to recognize the few children with serious conditions from the majority who have entered puberty early but are still medically normal. Early sexual development warrants evaluation because it may: One possible treatment is with anastrozole . GnRH agonists, including histrelin , triptorelin , or leuprorelin , are other possible treatments. Non-continuous use of GnRH agonists stimulates

2448-546: The treatment of central precocious puberty resulting from conditions like hypothalamic hamartomas or congenital adrenal hyperplasia, where early onset of puberty is a symptom. Additionally, puberty blockers can be prescribed for children with severe forms of idiopathic short stature, allowing for more time for growth before the closure of growth plates. In the USA, since 1993, the US Food and Drug Administration (FDA ) has supported

2499-489: The use of puberty blockers to treat precocious puberty. Currently under FDA regulation the use of puberty blockers is considered on-label for the treatment of central precocious puberty. ] For years, the FDA , Endocrine Society , American Academy of Pediatrics(AAP) and many other pediatric associations have supported the use of Gonadotropin-releasing hormone analogs (GnRHas) in central precocious puberty (CPP). In 2009,

2550-431: The western average for menstruation is about 12.7 years." In addition to diet and exercise habits, exposure to chemicals that mimic estrogen (known as xenoestrogens ) is another possible cause of early puberty in girls. Bisphenol A , a xenoestrogen found in hard plastics , has been shown to affect sexual development. "Factors other than obesity, however, perhaps genetic and/or environmental ones, are needed to explain

2601-544: The western world. The incidence of ONH is increasing, although it is difficult to estimate the true prevalence. Between 1980 and 1999, the occurrences of ONH in Sweden increased four-fold to 7.2 per 100,000, while all other causes of childhood blindness had declined. In 1997, ONH overtook retinopathy of prematurity as the single leading cause of infant blindness in Sweden, with 6.3 in every 100,000 births diagnosed with ONH. The most recent prevalence report out of England in 2006

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