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Due to its mild presentation, MAIS often goes unnoticed and untreated. Management of MAIS is currently limited to symptomatic management; methods to correct a malfunctioning androgen receptor protein that result from an AR gene mutation are not currently available. Treatment includes surgical correction of mild gynecomastia, minor hypospadias repair, and testosterone supplementation. Supraphysiological doses of testosterone have been shown to correct diminished secondary sexual characteristics in men with MAIS, as well as to reverse infertility due to low sperm count. As is the case with PAIS, men with MAIS will experience side effects from androgen therapy (such as the suppression of the hypothalamic-pituitary-gonadal axis) at a higher dosage than unaffected men. Careful monitoring is required to ensure the safety and efficacy of treatment. Regular breast and prostate examinations may be necessary due to comorbid association with breast and prostate cancers.
Management of AIS is currently limited to symptomatic management; no method is currently available to correct the malfunctioning androgen receptor proteins produced by "AR" gene mutations. Areas of management include sex assignment, genitoplasty, gonadectomy in relation to tumor risk, hormone replacement therapy, genetic counseling, and psychological counseling.
Preimplantation genetic diagnosis (PGD or PIGD) refers to genetic profiling of embryos prior to implantation (as a form of embryo profiling), and sometimes even of oocytes prior to fertilization. When used to screen for a specific genetic sequence, its main advantage is that it avoids selective pregnancy termination, as the method makes it highly likely that a selected embryo will be free of the condition under consideration.
In the UK, AIS appears on a list of serious genetic diseases that may be screened for via PGD. Some ethicists, clinicians, and intersex advocates have argued that screening embryos to specifically exclude intersex traits are based on social and cultural norms as opposed to medical necessity.
Exposure of spermatozoa to lifestyle, environmental and/or occupational hazards may increase the risk of aneuploidy. Cigarette smoke is a known aneugen (aneuploidy inducing agent). It is associated with increases in aneuploidy ranging from 1.5 to 3.0-fold. Other studies indicate factors such as alcohol consumption, occupational exposure to benzene, and exposure to the insecticides fenvalerate and carbaryl also increase aneuploidy.
Mild androgen insensitivity syndrome (MAIS) is a condition that results in a mild impairment of the cell's ability to respond to androgens. The degree of impairment is sufficient to impair spermatogenesis and / or the development of secondary sexual characteristics at puberty in males, but does not affect genital differentiation or development. Female genital and sexual development is not significantly affected by the insensitivity to androgens; as such, MAIS is only diagnosed in males. The clinical phenotype associated with MAIS is a normal male habitus with mild spermatogenic defect and / or reduced secondary terminal hair.
MAIS is one of three types of androgen insensitivity syndrome, which is divided into three categories that are differentiated by the degree of genital masculinization: complete androgen insensitivity syndrome (CAIS) is indicated when the external genitalia is that of a normal female, mild androgen insensitivity syndrome (MAIS) is indicated when the external genitalia is that of a normal male, and partial androgen insensitivity syndrome (PAIS) is indicated when the external genitalia is partially, but not fully masculinized.
Androgen insensitivity syndrome is the largest single entity that leads to 46,XY undermasculinization.
To some extent, it is possible to change testicular size. Short of direct injury or subjecting them to adverse conditions, e.g., higher temperature than they are normally accustomed to, they can be shrunk by competing against their intrinsic hormonal function through the use of externally administered steroidal hormones. Steroids taken for muscle enhancement (especially anabolic steroids) often have the undesired side effect of testicular shrinkage.
Similarly, stimulation of testicular functions via gonadotropic-like hormones may enlarge their size. Testes may shrink or atrophy during hormone replacement therapy or through chemical castration.
In all cases, the loss in testes volume corresponds with a loss of spermatogenesis.
The primary management of cryptorchidism is watchful waiting, due to the high likelihood of self-resolution. Where this fails, a surgery, called orchiopexy, is effective if inguinal testes have not descended after 4–6 months. Surgery is often performed by a pediatric urologist or pediatric surgeon, but in many communities still by a general urologist or surgeon.
When the undescended testis is in the inguinal canal, hormonal therapy is sometimes attempted and very occasionally successful. The most commonly used hormone therapy is human chorionic gonadotropin (HCG). A series of hCG injections (10 injections over 5 weeks is common) is given and the status of the testis/testes is reassessed at the end. Although many trials have been published, the reported success rates range widely, from roughly 5 to 50%, probably reflecting the varying criteria for distinguishing retractile testes from low inguinal testes. Hormone treatment does have the occasional incidental benefits of allowing confirmation of Leydig cell responsiveness (proven by a rise of the testosterone by the end of the injections) or inducing additional growth of a small penis (via the testosterone rise). Some surgeons have reported facilitation of surgery, perhaps by enhancing the size, vascularity, or healing of the tissue. A newer hormonal intervention used in Europe is the use of GnRH analogs such as nafarelin or buserelin; the success rates and putative mechanism of action are similar to hCG, but some surgeons have combined the two treatments and reported higher descent rates. Limited evidence suggests that germ cell count is slightly better after hormone treatment; whether this translates into better sperm counts and fertility rates at maturity has not been established. The cost of either type of hormone treatment is less than that of surgery and the chance of complications at appropriate doses is minimal. Nevertheless, despite the potential advantages of a trial of hormonal therapy, many surgeons do not consider the success rates high enough to be worth the trouble since the surgery itself is usually simple and uncomplicated.
In cases where the testes are identified preoperatively in the inguinal canal, orchiopexy is often performed as an outpatient and has a very low complication rate. An incision is made over the inguinal canal. The testis with accompanying cord structure and blood supply is exposed, partially separated from the surrounding tissues ("mobilized"), and brought into the scrotum. It is sutured to the scrotal tissue or enclosed in a "subdartos pouch." The associated passage back into the inguinal canal, an inguinal hernia, is closed to prevent re-ascent.
In patients with intraabdominal maldescended testis, laparoscopy is useful to see for oneself the pelvic structures, position of the testis and decide upon surgery ( single or staged procedure ).
Surgery becomes more complicated if the blood supply is not ample and elastic enough to be stretched into the scrotum. In these cases, the supply may be divided, some vessels sacrificed with expectation of adequate collateral circulation. In the worst case, the testis must be "auto-transplanted" into the scrotum, with all connecting blood vessels cut and reconnected ("anastomosed").
When the testis is in the abdomen, the first stage of surgery is exploration to locate it, assess its viability, and determine the safest way to maintain or establish the blood supply. Multi-stage surgeries, or autotransplantation and anastomosis, are more often necessary in these situations. Just as often, intra-abdominal exploration discovers that the testis is non-existent ("vanished"), or dysplastic and not salvageable.
The principal major complication of all types of orchiopexy is a loss of the blood supply to the testis, resulting in loss of the testis due to ischemic atrophy or fibrosis.
Cryptorchidism is rarer in cats than it is in dogs. In one study 1.9% of intact male cats were cryptorchid. Persians are predisposed. Normally the testicles are in the scrotum by the age of six to eight weeks. Male cats with one cryptorchid testicle may still be fertile; however, male cats with two cryptorchid testicles are most likely to be sterile. Urine spraying is one indication that a cat with no observable testicles may not be neutered; other signs are the presence of enlarged jowls, thickened facial and neck skin, and spines on the penis (which usually regress within six weeks after castration). Most cryptorchid cats present with an inguinal testicle.
Testicular tumors and testicular torsion are rare in cryptorchid cats, but castration is usually performed due to unwanted behavior such as urine spraying.
By 2010 over 100 successful pregnancies have been reported using IVF technology with surgically removed sperm material from males with Klinefelter syndrome. Microdissection testicular sperm extraction in adult men with Klinefelter syndrome reported success rates of up to 45%.
Children with XXY differ little from other children. Although they can face problems during adolescence, often emotional and behavioral, and difficulties at school, most of them can achieve full independence from their families in adulthood. Most can lead a normal, healthy life.
The results of a study carried out on 87 Australian adults with the syndrome shows that those who have had a diagnosis and appropriate treatment from a very young age had a significant benefit with respect to those who had been diagnosed in adulthood.
There is research suggesting Klinefelter syndrome substantially decreases life expectancy among affected individuals, though the evidence is not definitive. A 1985 publication identified a greater mortality mainly due to diseases of the aortic valve, development of tumors and possible subarachnoid hemorrhages, reducing life expectancy by about 5 years. Later studies have reduced this estimated reduction to an average of 2.1 years. These results are still questioned data, are not absolute, and will need further testing.
Testicular size as a proportion of body weight varies widely. In the mammalian kingdom, there is a tendency for testicular size to correspond with multiple mates (e.g., harems, polygamy). Production of testicular output sperm and spermatic fluid is also larger in polygamous animals, possibly a spermatogenic competition for survival. The testes of the right whale are likely to be the largest of any animal, each weighing around 500 kg (1,100 lb).
Among the Hominidae, gorillas have little female promiscuity and sperm competition and the testes are small compared to body weight (0.03%). Chimpanzees have high promiscuity and large testes compared to body weight (0.3%). Human testicular size falls between these extremes (0.08%).
Testis weight also varies in seasonal breeders like deer and horses. The change is related to changes in testosterone production.
Human testicles are smaller than chimpanzee testicles but larger than gorilla testicles.
Spermatogenesis arrest is a complex process of interruption in the differentiation of germinal cells of specific cellular type, which elicits an altered spermatozoa formation. Spermatogenic arrest is usually due to genetic factors resulting in irreversible azoospermia. However some cases may be consecutive to hormonal, thermic, or toxic factors and may be reversible either spontaneously or after a specific treatment.
One of the challenging aspects of long-term management is optimizing growth so that a child with CAH achieves his or her height potential because both undertreatment and overtreatment can reduce growth or the remaining time for growth. While glucocorticoids are essential for health, dosing is always a matter of approximation. In even mildly excessive amounts, glucocorticoids slow growth. On the other hand, adrenal androgens are readily converted to estradiol, which accelerates bone maturation and can lead to early epiphyseal closure. This narrow target of optimal dose is made more difficult to obtain by the imperfect replication of normal diurnal plasma cortisol levels produced by 2 or 3 oral doses of hydrocortisone. As a consequence, average height losses of about 4 inches (10 cm) have been reported with traditional management.
Traditionally, pediatric endocrinologists have tried to optimize growth by measuring a child every few months to assess current rate of growth, by checking the bone age every year or two, by periodically measuring 17OHP and testosterone levels as indicators of adrenal suppression, and by using hydrocortisone for glucocorticoid replacement rather than longer-acting prednisone or dexamethasone.
The growth problem is even worse in the simple virilizing forms of CAH which are detected when premature pubic hair appears in childhood, because the bone age is often several years advanced at the age of diagnosis. While a boy (or girl) with simple virilizing CAH is taller than peers at that point, he will have far fewer years remaining to grow, and may go from being a very tall 7-year-old to a 62-inch 13-year-old who has completed growth. Even with adrenal suppression, many of these children will have already had central precocious puberty triggered by the prolonged exposure of the hypothalamus to the adrenal androgens and estrogens. If this has begun, it may be advantageous to suppress puberty with a gonadotropin-releasing hormone agonist such as leuprolide to slow continuing bone maturation.
In recent years some newer approaches to optimizing growth have been researched and are beginning to be used. It is possible to reduce the effects of androgens on the body by blocking the receptors with an antiandrogen such as flutamide and by reducing the conversion of testosterone to estradiol. This conversion is mediated by aromatase and can be inhibited by aromatase blockers such as testolactone. Blocking the effects and conversions of estrogens will allow use of lower doses of glucocorticoids with less risk of acceleration of bone maturation. Other proposed interventions have included bilateral adrenalectomy to remove the androgen sources, or growth hormone treatment to enhance growth.
For a more extensive review of the difficulties of optimizing growth, see Migeon CJ, Wisneiewski AB. Congenital adrenal hyperplasia owing to 21-hydroxylase deficiency: growth, development, and therapeutic considerations. Endocrinol Metab Clin N Am 30:193-206, 2001.
As growth ends, management in girls with CAH changes focus to optimizing reproductive function. Both excessive testosterone from the adrenals and excessive glucocorticoid treatment can disrupt ovulation, resulting in irregularity of menses or amenorrhea, as well as infertility. Continued monitoring of hormone balance and careful readjustment of glucocorticoid dose can usually restore fertility, but as a group, women with CAH have a lower fertility rate than a comparable population.
CAH has little effect on male fertility unless an adult stops taking his glucocorticoid medication entirely for an extended time, in which case excessive adrenal testosterone may reduce testicular production as well as spermatogenesis.
A number of twin gestations have occurred where each uterus carried its pregnancy separately. A recent example occurred on February 26, 2009, when Sarah Reinfelder of Sault Ste. Marie, Michigan delivered two healthy, although seven weeks premature, infants by cesarean section at Marquette General Hospital. It is possible that the deliveries occur at different times, thus the delivery interval could be days or even weeks.
In the United States, uterus didelphys is reported to occur in 0.1–0.5% of women. It is difficult to know the exact occurrence of this anomaly, as it may go undetected in the absence of medical and reproductive complications.
The incidence of ovarian remnant syndrome is difficult to determine. The available data are limited to case reports or to retrospective case series. The best available data are from a study describing the frequency and outcome of laparoscopy in women with chronic pelvic pain and/or a pelvic mass who were found to have ovarian remnants. In 119 women who underwent hysterectomy and oophorectomy by laparoscopy, ovarian remnants were known in 5 and were found during surgery in 21 patients (18%).[2] However, this was a small study and the participants were only symptomatic women. Therefore, it is not known whether the data can be extrapolated to include all women who have undergone oophorectomy.
Treatment for ovarian remnant (ORS) is generally indicated for women with suspected ORS who have symptoms (such as pain); have a pelvic mass; or need or desire complete removal of to decrease the risk of ovarian (for example, BRCA ). The mainstay of treatment is surgery to remove the residual ovarian tissue. Women with ORS with a pelvic mass should have appropriate evaluation for malignancy (cancer). Hormonal therapy to suppress ovarian function is an alternative treatment for those who refuse surgery, or those who are not candidates for surgery. Medications may be used to treat ORS and include GnRH agonists, danazol, or progesterone.
Polar body diagnosis (PBD) can be use to detect maternally derived chromosomal aneuploidies as well as translocations in oocytes. The advantage of PBD over PGD is that it can be accomplished in a short amount of time. This is accomplished through zona drilling or laser drilling.
Some of the childhood management issues are similar those of 21-hydroxylase deficiency:
- Replacing mineralocorticoid with fludrocortisone
- Suppressing DHEA and replacing cortisol with glucocorticoid
- Providing extra glucocorticoid for stress
- Close monitoring and perhaps other adjunctive measures to optimize growth
- Deciding whether surgical repair of virilized female genitalia is warranted
However, unlike 21-hydroxylase CAH, children with 3β-HSD CAH may be unable to produce adequate amounts of testosterone (boys) or estradiol (girls) to effect normal pubertal changes. Replacement testosterone or estrogen and progesterone can be initiated at adolescence and continued throughout adult life. Fertility may be impaired by the difficulty of providing appropriate sex hormone levels in the gonads even though the basic anatomy is present.
Congenital adrenal hyperplasia (CAH) are any of several autosomal recessive diseases resulting from mutations of genes for enzymes mediating the biochemical steps of production of mineralocorticoids, glucocorticoids or sex steroids from cholesterol by the adrenal glands (steroidogenesis).
Most of these conditions involve excessive or deficient production of sex steroids and can alter development of primary or secondary sex characteristics in some affected infants, children, or adults.
Treatment of all forms of CAH may include any of:
1. supplying enough glucocorticoid to reduce hyperplasia and overproduction of androgens or mineralocorticoids
2. providing replacement mineralocorticoid and extra salt if the person is deficient
3. providing replacement testosterone or estrogen at puberty if the person is deficient
4. additional treatments to optimize growth by delaying puberty or delaying bone maturation
All of these management issues are discussed in more detail in congenital adrenal hyperplasia due to 21-hydroxylase deficiency.
Dexamethasone is used as an off-label early pre-natal treatment for the symptoms of CAH in female fetuses, but it does not treat the underlying congenital disorder. A 2007 Swedish clinical trial found that treatment may cause cognitive and behavioural defects, but the small number of test subjects means the study cannot be considered definitive. A 2012 American study found no negative short term outcomes, but "lower cognitive processing in CAH girls and women with long-term DEX exposure." Administration of pre-natal dexamethasone has been the subject of controversy over issues of informed consent and because treatment must predate a clinical diagnosis of CAH in the female fetus, especially because in utero dexamethasone may cause metabolic problems that are not evident until later in life; Swedish clinics ceased recruitment for research in 2010.
The treatment has also raised concerns in LGBT and bioethics communities following publication of an essay posted to the forum of the Hastings Center, and research in the Journal of Bioethical Inquiry, which found that pre-natal treatment of female fetuses was suggested to prevent those fetuses from becoming lesbians after birth, may make them more likely to engage in "traditionally" female-identified behaviour and careers, and more interested in bearing and raising children. Citing a known attempt by a man using his knowledge of the fraternal birth order effect to avoid having a homosexual son by using a surrogate, the essayists (Professor Alice Dreger of Northwestern University's Feinberg School of Medicine, Professor Ellen Feder of American University and attorney Anne Tamar-Mattis) suggest that pre-natal "dex" treatments constitute the first known attempt to use "in utero" protocols to reduce the incidence of homosexuality and bisexuality in humans. Research on the use of prenatal hormone treatments to prevent homosexuality stretches back to the early 1990s or earlier.
Since CAH is a recessive gene, both the mother and father must be recessive carriers of CAH for a child to have CAH. Due to advances in modern medicine, those couples with the recessive CAH genes have an option to prevent CAH in their offspring through preimplantation genetic diagnosis (PGD). In PGD, the egg is fertilized outside the women's body in a petri dish (IVF). On the 3rd day, when the embryo has developed from one cell to about 4 to 6 cells, one of those cells is removed from the embryo without harming the embryo. The embryo continues to grow until day 5 when it is either frozen or implanted into the mother. Meanwhile, the removed cell is analyzed to determine if the embryo has CAH. If the embryo is determined to have CAH, the parents may make a decision as to whether they wish to have it implanted in the mother or not.
Meta-analysis of the studies supporting the use of dexamethasone on CAH at-risk fetuses found "less than one half of one percent of published 'studies' of this intervention were regarded as being of high enough quality to provide meaningful data for a meta-analysis. Even these four studies were of low quality" ... "in ways so slipshod as to breach professional standards of medical ethics" and "there were no data on long-term follow-up of physical and metabolic outcomes in children exposed to dexamethasone".
Medications consist mostly of antiandrogens, drugs that block the effects of androgens like testosterone and dihydrotestosterone (DHT) in the body, and include:
- Spironolactone: An antimineralocorticoid with additional antiandrogenic activity at high dosages
- Cyproterone acetate: A dual antiandrogen and progestogen. In addition to single form, it is also available in some formulations of combined oral contraceptives at a low dosage (see below). It has a risk of liver damage.
- Flutamide: A pure antiandrogen. It has been found to possess equivalent or greater effectiveness than spironolactone, cyproterone acetate, and finasteride in the treatment of hirsutism. However, it has a high risk of liver damage and hence is no longer recommended as a first- or second-line treatment.
- Bicalutamide: A pure antiandrogen. It is effective similarly to flutamide but is much safer as well as better-tolerated.
- Birth control pills: Consist of an estrogen, usually ethinylestradiol, and a progestin. They are thought to work by 1) stimulating production of sex hormone-binding globulin in the liver, which decreases free concentrations of testosterone in the blood; and by 2) suppressing luteinizing hormone (LH) secretion from the pituitary gland, which decreases production of testosterone by the gonads. Hence, they are functional antiandrogens. In addition, certain birth control pills contain a progestin that also has antiandrogenic activity. Examples include birth control pills containing cyproterone acetate, chlormadinone acetate, drospirenone, and dienogest.
- Finasteride and dutasteride: 5α-Reductase inhibitors. They inhibit the production of the potent androgen DHT.
- GnRH analogues: Suppress androgen production by the gonads and reduce androgen concentrations to castrate levels.
- Metformin: Antihyperglycemic drug used for diabetes mellitus. However, it is also effective in treatment of hirsutism associated with insulin resistance (e.g. polycystic ovary syndrome)
- Eflornithine: Blocks putrescine that is necessary for the growth of hair follicles
In cases of hyperandrogenism specifically due to congenital adrenal hyperplasia, administration of glucocorticoids will return androgen levels to normal.
Congenital adrenal hyperplasia due to 3β-hydroxysteroid dehydrogenase deficiency is an uncommon form of congenital adrenal hyperplasia (CAH) resulting from a mutation in the gene for one of the key enzymes in cortisol synthesis by the adrenal gland, 3β-hydroxysteroid dehydrogenase (3β-HSD) type II (HSD3B2). As a result, higher levels of 17OH-pregnenolone appear in the blood with adrenocorticotropic hormone (ACTH) challenge, which stimulates adrenal corticosteroid synthesis.
There is a wide spectrum of clinical presentations of 3β-HSD CAH, from mild to severe forms. The uncommon severe form results from a complete loss of enzymatic activity and manifests itself in infancy as salt wasting due to the loss of mineralocorticoids. Milder forms resulting from incomplete loss of 3β-HSD type II function do not present with adrenal crisis, but can still produce virilization of genetically female infants and undervirilization of genetically male infants. As a result, this form of primary hypoadrenalism is the only form of CAH that can cause ambiguous genitalia in both genetic sexes.
Many women with unwanted hair seek methods of hair removal. However, the causes of the hair growth should be evaluated by a physician, who can conduct blood tests, pinpoint the specific origin of the abnormal hair growth, and advise on the treatment.