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When an infant is born with PSH, the most difficult management decision has often been the sex assignment, since genitalia with this degree of ambiguity do not resemble either sex very well with respect to looks or function. Many infants with PPHS have been assigned and raised as female despite presence of testes and XY chromosomes.
Nearly all parents of infants with PPSH are offered surgical reconstruction, to either further masculinize or feminize the external genitalia.
Treatment with testosterone postnatally does not close the urethra or change the malformation, but in some cases may enlarge the penis slightly.
Hypospadias is among the most common birth defects in the world and is said to be the second-most common birth defect in the male reproductive system, occurring once in every 250 males.
Due to variations in the reporting requirements of different national databases, data from such registries cannot be used to accurately determine either incidence of hypospadias or geographical variations in its occurrences.
Surgery is usually recommended for hypospadias, with the goal to restore normal appearance and function to the penis. A urinary opening that is not surrounded by glans tissue is more likely to “spray” the urine, which can cause a man to sit to urinate because he cannot reliably stand and hit the toilet. Downward curvature of the penis can impair sexual activity as an adult.
Surgery extends the urinary channel to the end of the penis, straightens bending, and corrects the foreskin abnormality by either circumcision or by repairing it to look normal (“prepucioplasty”), depending on the desire of care-givers.
When the hypospadias is third degree (penoscrotal), or has associated birth defects such as chordee or cryptorchidism, the best management can be a more complicated decision. A karyotype and endocrine evaluation should be performed to detect intersex conditions or hormone deficiencies. If the penis is small, testosterone or human chorionic gonadotropin (hCG) injections may be given to enlarge it before surgery.
Surgical repair of severe hypospadias may require multiple procedures and mucosal grafting. Preputial skin is often used for grafting and circumcision should be avoided before repair. In a minority of patients with severe hypospadias, surgery produces unsatisfactory results, such as scarring, curvature, or formation of urethral fistulas, diverticula, or strictures. A fistula is an unwanted opening through the skin along the course of the urethra, and can result in urinary leakage or an abnormal stream. A diverticulum is an "outpocketing" of the lining of the urethra which interferes with urinary flow and may result in posturination leakage. A stricture is a narrowing of the urethra severe enough to obstruct flow. Reduced complication rates even for third-degree repair (e.g., fistula rates below 5%) have been reported in recent years from centers with the most experience, and surgical repair is now performed for the vast majority of infants with hypospadias.
The principal treatment of chordee is surgery in infancy, usually by a pediatric urologist. With chordees caused by circumcision, the preferred method of surgical treatment is a z-plasty. The preferred time for surgery is between the ages of 6 and 18 months and correction is usually successful.
Unfortunately, the number of differentials to consider for PAIS is particularly large. Prompt diagnosis is particularly urgent when a child is born with ambiguous genitalia, as some causes are associated with potentially life-threatening adrenal crises. Determination of testosterone, testosterone precursors and dihydrotestosterone (DHT) at baseline and / or after human chorionic gonadotropin (hCG) stimulation can be used to exclude such defects in androgen biosynthesis.
Approximately one half of all 46,XY individuals born with ambiguous genitalia will not receive a definitive diagnosis. Androgen receptor (AR) gene mutations cannot be found in 27% to 72% of individuals with PAIS. As a result, genetic analysis can be used to confirm a diagnosis of PAIS, but it cannot be used to rule out PAIS. Evidence of abnormal androgen binding in a genital skin fibroblast study has long been the gold standard for the diagnosis of PAIS, even when an AR mutation is not present. However, some cases of PAIS, including AR-mutant-positive cases, will show normal androgen binding. A family history consistent with X-linked inheritance is more commonly found in AR-mutant-positive cases than AR-mutant-negative cases.
The use of dynamic endocrine tests is particularly helpful in isolating a diagnosis of PAIS. One such test is the human chorionic gonadotropin (hCG) stimulation test. If the gonads are testes, there will be an increase in the level of serum testosterone in response to the hCG, regardless of testicular descent. The magnitude of the testosterone increase can help differentiate between androgen resistance and gonadal dysgenesis, as does evidence of a uterus on ultrasound examination. Testicular function can also be assessed by measuring serum anti-Müllerian hormone levels, which in turn can further differentiate PAIS from gonadal dysgenesis and bilateral anorchia.
Another useful dynamic test involves measuring the response to exogenous steroids; individuals with AIS show a decreased response in serum sex hormone binding globulin (SHBG) after a short term administration of anabolic steroids. Two studies indicate that measuring the response in SHBG after the administration of stanozolol could help to differentiate individuals with PAIS from those with other causes of ambiguous genitalia, although the response in individuals with predominantly male phenotypes overlaps somewhat with the response in normal males.
It is considered a form of 5-alpha-reductase deficiency involving SRD5A2.
The decision of whether to raise an individual with PAIS as a boy or a girl may not be obvious; grades 3 and 4 in particular present with a phenotype that may be difficult to classify as primarily male or female, and some will be incapable of virilization at puberty. Parents of an affected newborn should seek immediate help at a center with an experienced multidisciplinary team, and should avoid gender assignment beforehand. Gender assignment should thereafter be expeditiously decided; current guidelines advise against waiting for the child to decide for his / herself. Key considerations involved in assigning gender include the appearance of the genitalia, the extent to which the child can virilize at puberty, surgical options and the postoperative sexual function of the genitalia, genitoplasty complexity, potential for fertility, and the projected gender identity of the child. The majority of individuals with PAIS are raised male.
Virilization capacity can be assessed by measuring the response to a trial of exogenous androgens; some studies have measured the growth of the phallus in response to exogenous testosterone or dihydrotestosterone, while others have measured the change in sex hormone binding globulin (SHBG) in response to the artificial androgen stanozolol to assess androgen sensitivity. Some experts have cautioned that it remains to be proved that a good response to exogenous androgens in neonates is a good predictor of androgen response at puberty. If a mutation in the AR gene is found, it is important to determine whether the mutation is inherited or de novo (i.e. a somatic mutation); a certain amount of the wild-type androgen receptor will be present in cases of somatic mutation, which can induce virilization at puberty. A genital skin fibroblast study and a human chorionic gonadotropin (hCG) stimulation test may also provide information helpful in the assessment of virilization capacity.
Psychosexual development is influenced by many factors, including the timing, amount, and type of androgen exposure, receptor functionality, and environment, and is thus difficult to predict. Gender identity begins to develop before 3 years of age, although the earliest age at which it can be reliably assessed has yet to be determined. Approximately 25% of individuals with PAIS are dissatisfied with their assigned gender, regardless of being raised as male or female. One study reports that 46,XY individuals born with micropenis and no hypospadias are better off being raised male, despite the success of some being raised female. Studies involving the more ambiguous phenotypic forms of PAIS are less decisive. Homosexuality with respect to assigned gender and atypical gender role behavior are known to occur more frequently in individual with PAIS, and may occur with or without gender dysphoria; neither should be interpreted as an indication of incorrect gender assignment. If an affected child does express feelings of gender dysphoria, the opportunity to explore such feelings with a psychologist experienced in treating intersex conditions should be accommodated. If feelings of gender dysphoria persist, gender reassignment should be initiated, possibly with the aid of a specialist in the field.
It is usually considered a congenital malformation of unknown cause. Since at an early stage of fetal development the penis is curved downward, it has been proposed that chordee results from an arrest of penile development at that stage.
The curvature of a chordee can involve
1. tethering of the skin with urethra and corpora of normal size;
2. curvature induced by fibrosis and contracture of the fascial tissue (Buck's fascia or dartos) surrounding the urethra;
3. disproportionately large corpora in relation to the urethral length without other demonstrable abnormality of either; or
4. a short, fibrotic urethra that tethers the penis downward (the least common type).
Severe degrees of chordee are usually associated with hypospadias, but mild degrees of curvature may occur in many otherwise normal males. When the curved penis is small and accompanied by hypospadias, deficiency of prenatal androgen effect can be inferred.
Conditions justifying newborn screening for any disorder include (1) a simple test with an acceptable sensitivity and specificity, (2) a dire consequence if not diagnosed early, (3) an effective treatment if diagnosed, and (4) a frequency in the population high enough to justify the expense. In the last decade more states and countries are adopting newborn screening for salt-wasting CAH due to 21-hydroxylase deficiency, which leads to death in the first month of life if not recognized.
The salt-wasting form of CAH has an incidence of 1 in 15,000 births and is potentially fatal within a month if untreated. Steroid replacement is a simple, effective treatment. However, the screening test itself is less than perfect. While the 17α-hydroxyprogesterone level is easy to measure and sensitive (rarely missing real cases), the test has a poorer specificity. Screening programs in the United States have reported that 99% of positive screens turn out to be false positives upon investigation of the infant. This is a higher rate of false positives than the screening tests for many other congenital metabolic diseases.
When a positive result is detected, the infant must be referred to a pediatric endocrinologist to confirm or disprove the diagnosis. Since most infants with salt-wasting CAH become critically ill by 2 weeks of age, the evaluation must be done rapidly despite the high false positive rate.
Levels of 17α-hydroxyprogesterone, androstenedione, and cortisol may play a role in screening.
Additional findings that may be present in HFGS according to the latest research are:
- Limited metacarpophalangeal flexion of the thumb or limited ability to oppose the thumb and fifth finger
- Hypoplastic thenar eminences
- Medial deviation of the great toe (hallux varus), a useful diagnostic sign when present
- Small great toenail
- Fifth-finger clinodactyly, secondary to a shortened middle phalanx
- Short feet
- Altered dermatoglyphics of the hands; when present, primarily involving distal placement of the axial triradius, lack of thenar or hypothenar patterning, low arches on the thumbs, thin ulnar loops (deficiency of radial loops and whorls), and a greatly reduced ridge count on the fingers
Radiographic findings
- Hypoplasia of the distal phalanx and first metacarpal of the thumbs and great toes
- Pointed distal phalanges of the thumb
- Lack of normal tufting of the distal phalanges of the great toes
- Fusions of the cuneiform to other tarsal bones or trapezium-scaphoid fusion of the carpals
- Short calcaneus
- Occasional bony fusions of the middle and distal phalanges of the second, third, fourth, or fifth toes
- Delayed carpal or tarsal maturation
- Metacarpophalangeal profile reflecting shortening of the first metacarpal, the first and second phalanges, and the second phalanx of the second and fifth digits
Urogenital Defects
Females may have the following:
- Vesicoureteral reflux secondary to ureteric incompetence
- Ectopic ureteral orifices
- Trigonal hypoplasia
- Hypospadiac urethra
- Subsymphyseal epispadias
- Patulous urethra
- Urinary incontinence (related to structural anomalies and weakness of the bladder sphincter muscle)
- Small hymenal opening
- Various degrees of incomplete Müllerian fusion with or without two cervices or a longitudinal vaginal septum
Males may have the following:
- Retrograde ejaculation (related to structural anomalies and weakness of the bladder sphincter muscle)
Urethroplasty refers to any open reconstruction of the urethra. Success rates range from 85% to 95% and depend on a variety of clinical factors, such as stricture as the cause, length, location, and caliber. Urethroplasty can be performed safely on men of all ages.
In the posterior urethra, anastomotic urethroplasty (with or without preservation of bulbar arteries) is typically performed after removing scar tissue.
In the bulbar urethra, the most common types of urethroplasty are anastomotic (with or without preservation of corpus spongiosum and bulbar arteries) and substitution with buccal mucosa graft, full-thickness skin graft, or split thickness skin graft. These are nearly always done in a single setting (or stage).
In the penile urethra, anastomotic urethroplasties are rare because they can lead to chordee (penile curvature due to a shortened urethra). Instead, most penile urethroplasties are substitution procedures utilizing buccal mucosa graft, full-thickness skin graft, or split thickness skin graft. These can be done in one or more setting, depending on stricture location, severity, cause and patient or surgeon preference.
Diagnosis is based on physical examination including radiographs of the hands and feet and imaging studies of the kidneys, bladder, and female reproductive tract. HOXA13 is the only gene known to be associated with HFGS. Approximately 60% of mutations are polyalanine expansions. Molecular genetic testing is clinically available.
Since CAH is an autosomal recessive disease, most children with CAH are born to parents unaware of the risk and with no family history. Each child will have a 25% chance of being born with the disease. Families typically wish to minimize the degree of virilization of a girl. There is no known prenatal harm to a male fetus from CAH, so treatment can begin at birth.
Adrenal glands of female fetuses with CAH begin producing excess testosterone by the 9th week of gestation. The most important aspects of virilization (urogenital closure and phallic urethra) occur between 8 and 12 weeks. Theoretically, if enough glucocorticoid could be supplied to the fetus to reduce adrenal testosterone production by the 9th week, virilization could be prevented and the difficult decision about timing of surgery avoided.
The challenge of preventing severe virilization of girls is twofold: detection of CAH at the beginning of the pregnancy, and delivery of an effective amount of glucocorticoid to the fetus without causing harm to the mother.
The first problem has not yet been entirely solved, but it has been shown that if dexamethasone is taken by a pregnant woman, enough can cross the placenta to suppress fetal adrenal function.
At present no program screens for risk in families who have not yet had a child with CAH. For families desiring to avoid virilization of a second child, the current strategy is to start dexamethasone as soon as a pregnancy has been confirmed even though at that point the chance that the pregnancy is a girl with CAH is only 12.5%. Dexamethasone is taken by the mother each day until it can be safely determined whether she is carrying an affected girl.
Whether the fetus is an affected girl can be determined by chorionic villus sampling at 9–11 weeks of gestation, or by amniocentesis at 15–18 weeks gestation. In each case the fetal sex can be determined quickly, and if the fetus is a male the dexamethasone can be discontinued. If female, fetal DNA is analyzed to see if she carries one of the known abnormal alleles of the "CYP21" gene. If so, dexamethasone is continued for the remainder of the pregnancy at a dose of about 1 mg daily.
Most mothers who have followed this treatment plan have experienced at least mild cushingoid effects from the glucocorticoid but have borne daughters whose genitalia are much less virilized.
Following urethroplasty, patients should be monitored for a minimum of 1 year, since the vast majority of recurrences occur within 1 year.
Because of the high rate of recurrence following dilation and other endoscopic approaches, the provider must maintain a high index of suspicion for recurrence when the patient presents with obstructive voiding symptoms or urinary tract infection.
Suspicion of a chromosome abnormality is typically raised due to the presence of developmental delays or birth defects. Diagnosis of distal 18q- is usually made from a blood sample. A routine chromosome analysis, or karyotype, is usually used to make the initial diagnosis, although it may also be made by microarray analysis. Increasingly, microarray analysis is also being used to clarify breakpoints. Prenatal diagnosis is possible using amniocentesis or chorionic villus sampling.
At present, treatment for distal 18q- is symptomatic, meaning the focus is on treating the signs and symptoms of the conditions as they arise. To ensure early diagnosis and treatment, people with distal 18q- are suggested to undergo routine screenings for thyroid, hearing, and vision problems.
Clinically, McKusick–Kaufman syndrome is characterized by a combination of three features: postaxial polydactyly, heart defects, and genital abnormalities:
- Vaginal atresia with hydrometrocolpos
- Double vagina and/or uterus.
- Hypospadias, chordee (a downward-curving penis), and undescended testes (cryptorchidism).
- ureter stenosis or ureteric atresia
McKusick–Kaufman syndrome is a genetic condition associated with MKKS.
The condition is named for Dr. Robert L. Kaufman and Victor McKusick. It is sometimes known by the abbreviation MKS. In infancy it can be difficult to distinguish between MKS and the related Bardet–Biedl syndrome, as the more severe symptoms of the latter condition rarely materialise before adulthood.