Pseudovaginal perineoscrotal hypospadias

Male sex determination: current concepts of male sexual differentiation

In order for an infant to develop as a phenotypically complete male or female, a cascade of complex molecular and morphological events must occur at the appropriate time and in the correct sequence during ontogeny. The male embryo's genetic sex is determined by its chromosomal constituents, the most important of which is the sex-determining gene, or testis-determining factor (TDF), on the Y chromosome. Male gonadal sex, or testis formation, is subsequently thought to be determined by this gene and by other secondary pathways. The male gonad, in turn, normally produces hormones such as testosterone and Mullerian inhibiting substance (MIS) that regulate differentiation of the internal and external genitalia, thus determining phenotypic sex. When an abnormality develops in any of the above three processes, an intersex infant with ambiguous genitalia results from the incongruent genetic, gonadal, and phenotypic sex. Clinically, such 46XY males with intersex abnormalities present challenges for gender assignment, timely surgical intervention, and appropriate hormonal therapy.

Gender verification in competitive sports

The possibility that men might masquerade as women and be unfair competitors in women's sports is accepted as outrageous by athletes and the public alike. Since the 1930s, media reports have fuelled claims that individuals who once competed as female athletes subsequently appeared to be men. In most of these cases there was probably ambiguity of the external genitalia, possibly as a result of male pseudohermaphroditism. Nonetheless, beginning at the Rome Olympic Games in 1960, the International Amateur Athletics Federation (IAAF) began establishing rules of eligibility for women athletes. Initially, physical examination was used as a method for gender verification, but this plan was widely resented. Thus, sex chromatin testing (buccal smear) was introduced at the Mexico City Olympic Games in 1968. The principle was that genetic females (46,XX) show a single X-chromatic mass, whereas males (46,XY) do not. Unfortunately, sex chromatin analysis fell out of common diagnostic use by geneticists shortly after the International Olympic Committee (IOC) began its implementation for gender verification. The lack of laboratories routinely performing the test aggravated the problem of errors in interpretation by inexperienced workers, yielding false-positive and false-negative results. However, an even greater problem is that there exist phenotypic females with male sex chromatin patterns (e.g. androgen insensitivity, XY gonadal dysgenesis). These individuals have no athletic advantage as a result of their congenital abnormality and reasonably should not be excluded from competition. That is, only the chromosomal (genetic) sex is analysed by sex chromatin testing, not the anatomical or psychosocial status. For all the above reasons sex chromatin testing unfairly excludes many athletes. Although the IOC offered follow-up physical examinations that could have restored eligibility for those 'failing' sex chromatin tests, most affected athletes seemed to prefer to 'retire'. All these problems remain with the current laboratory based gender verification test, polymerase chain reaction based testing of the SRY gene, the main candidate for male sex determination. Thus, this 'advance' in fact still fails to address the fundamental inequities of laboratory based gender verification tests. The IAAF considered the issue in 1991 and 1992, and concluded that gender verification testing was not needed. This was thought to be especially true because of the current use of urine testing to exclude doping: voiding is observed by an official in order to verify that a sample from a given athlete has actually come from his or her urethra. That males could masquerade as females in these circumstances seems extraordinarily unlikely. Screening for gender is no longer undertaken at IAAF competitions.

Effect of 5-alpha-reductase inhibitor, 4-MAPC, on testicular descent in male rat

Testicular descent has been reported to be a dihydrotestosterone (DHT) dependent event. To further elucidate the role of DHT in the process of testicular descent, a group of rats were treated with the 5-alpha reductase inhibitor, 4-MAPC, from birth to day 28 of age and the incidence of testicular descent as well as ventral prostate weight was noted at day 29 of age. It was determined that in the doses used, 4-MAPC failed to prevent testicular descent. Because 4-MAPC inhibited ventral prostate weight by only 53% (as compared to a 75% inhibition by castration), the failure of the 4-MAPC to prevent testicular descent could be due to its inability to completely inhibit tissue 5-alpha reductase activity. The results of this study do not mitigate against the role of other nonhormonal factors working in tandem with DHT in the induction of testicular descent in this animal model.

Premature centromeric divisions and prominent telomeres in a patient with persistent mullerian duct syndrome

A 35-year-old, rare male pseudohermaphrodite with inguinal hernia, testis, fallopian tube and uterus, symptoms referrable to persistent Mullerian duct syndrome, is described. The patient has a 46,XY karyotype in 50% of metaphases, while the remaining metaphases show premature cnetromeric divisions and hypoploid counts.

Male pseudohermaphroditism due to 5 alpha-reductase deficiency in a Swedish family

Three sibs with an inherited form of male pseudohermaphroditism are described. They were all born with ambiguous external genitalia but no diagnosis of a possible enzyme defect was made during childhood. First seen at the ages of 16, 14 and 10 years respectively, they were investigated in order to establish the pathogenetic nature of the disorder. Serum concentrations of testosterone and dihydrotestosterone before and after stimulation with human chorionic gonadotropin suggested 5 alpha-reductase deficiency. Measurement of steroid metabolites in urine confirmed this diagnosis. It is essential to recognize this condition in order to decide the sex of rearing of the children.

Abnormal sexual differentiation and neoplasia

The prevalence of neoplasia is increased in individuals with certain disorders of sexual differentiation. Etiology and frequency of neoplasia vary with the particular disorder. In uncomplicated cryptorchidism, the testis is at least 10 times more likely to undergo neoplastic transformation than a normal scrotal testis. Neoplasia probably is a function of both testicular location (intraabdominal) and underlying dysgenetic structure. If cryptorchidism is unilateral, and if orchiopexy has not been performed prior to age 6-10 years, orchiectomy should be encouraged. In those forms of gonadal dysgenesis not associated with a Y chromosome (e.g., 45,X; 45,X/46,XX; 46,XX) there is no definite increase in neoplasia, suggesting that elevated gonadotropin levels per se are not carcinogenic. Gonadal tumors are found in at least 30% of individuals with XY gonadal dysgenesis and are particularly frequent (55%) in H-Y antigen-positive patients. These tumors are almost always gonadoblastomas or dysgerminomas. Similar tumors are found in 15%-20% of 45,X/46,XY individuals. In either situation the neoplastic transformation could be a) secondary to the existence of XY gonadal tissue in an inhospitable environment, or b) integrally related to that process--genetic or cytogenetic--producing the dysgenetic gonads. The risk of neoplasia is sufficiently high that most of these patients should be offered early gonadal extirpation. The prevalence of gonadal tumors is not increased in Klinefelter's syndrome, further indicating that gonadotropins are not carcinogenic per se. However, Klinefelter patients are 20 times more likely to develop a carcinoma of the breast than are 46,XY males. Extragonadal germ cell tumors also are more common. In female pseudohermaphrodites there is probably no increased risk of neoplasia, whereas, in true hermaphrodites neoplasia is unusual but does occur. Neoplasia occurs in patients with complete testicular feminization (complete androgen insensitivity) but rarely in those with incomplete testicular feminization/Reifenstein's syndrome, 5 alpha-reductase deficiency, anorchia, agonadia, or testosterone biosynthetic defects. In complete testicular feminization the risk of malignant tumors is small prior to age 25. After age 25, it is about 2%-5%. Orchiectomy is recommended after pubertal feminization.

A clinico-genetic investigation of Leydig cell hypoplasia

We report on a kindred including a patient (46,XY) with typical manifestations of Leydig cell hypoplasia who was born to parents who were first cousins. A sister had secondary amenorrhea possibly due to primary ovarian dysfunction. Analysis of six pedigrees fits to a male-limited autosomal recessive pattern of inheritance; its implication for the mutational dynamics in the populations is evaluated.

Hormonal regulation of testicular descent

The involvement of testosterone in testicular descent and the mechanism of testicular descent were analyzed and discussed.

Large prostatic utricles and related structures, urogenital sinus and other forms of urethrovaginal confluence

The urethrograms and clinical records of 106 children with a large prostatic utricle or related structures, urogenital sinus in intersex disorders and other types of urethrovaginal confluence were reviewed. There were 27 boys with normal external genitalia, 19 cases of male hypospadias, 1 case of male pseudohermaphroditism, 7 cases of mixed gonadal dysgenesis, 1 case of true hermaphroditism, 32 cases of female pseudohermaphroditism, 11 normal girls with urethrovaginal confluence and 8 cases of cloacal malformation. Among the patients of the first 2 groups 10 had an imperforate anus, 7 the prune belly syndrome, 6 Down's syndrome and 2 posterior urethral valves.

Perineal reconstruction in ambiguous genitalia infants raised as females

Sixty-six patients with ambiguous genitalia, representing a combined experience, underwent reconstruction of the perineum to achieve a feminine phenotype. These patients represent four major etiologic groups, adrenogenital syndrome, male pseudohermaphroditism, mixed gonadal dysgenesis, and true hermaphroditism. If the patient is to be raised as a female, the perineum is reconstructed early in the neonatal period by doing a clitoral recession, labial reduction, and vaginal exteriorization. The latter is delayed if the vagina enters the urogenital sinus high, until 2 years. The factors affecting the choice of gender and the details and the timing of the surgical techniques are described.

Mechanical genital maldevelopment presenting as pseudovaginal perineoscrotal hypospadias

Pseudovaginal perineoscrotal hypospadias is the descriptive terminology of a phenotypic genital abnormality that may develop from multiple etiologic factors, such as defective virilization-masculinization owing to deficient androgenic synthesis, defective androgenic action or mechanical embryologic failure. The case presented herein typifies a mechanical abnormality that results in perineal hypospadias with the appearance of a vaginal introitus but with rectal mucosa incorporated in the urethral opening.

Management of neonates and children with male pseudohermaphroditism

Twenty-five patients with male pseudohermaphroditism were treated. Causes included (1) inadequate testosterone production, (2) incomplete conversion of testosterone to dihydrotestosterone, and (3) insufficient androgen-binding protein at the target cell. These various problems can be defined accurately today. These infants should be studied early to define which gender role is more appropriate. Change in gender assignment later can be disastrous. An individual raised in the female role, but with incomplete internal structures, can cope with life better than one raised in the male role but lacking a satisfactory phallus. In general, we believe most male pseudohermaphrodites should be raised as females, performing appropriate alterations at an early age.

Diagnosis and management of the infant with genital ambiguity

Clinical management of a child with ambiguous external genitalia requires physicians to consider the immediate management of the condition, as well as parental reactions. They must also obtain the necessary data upon which to make a diagnosis. This review summarizes the most common disorders causing genital ambiguity and suggests approaches toward delineation.

Male pseudohermaphroditism due to steroid 5-alpha-reductase deficiency

A new inherited form of male pseudohermaphroditism has been investigated in a pedigree of 24 families with 38 affected males. At birth, the affected males (46 XY) have a clitoral-like phallus, bifid scrotum and urogenital sinus. The testes are in the inguinal canals or labial-scrotal folds. The Wolffian structures are normally differentiated; there are no Mullerian structures. At puberty a muscular male habitus develops with growth of the phallus and scrotum, voice change and no gynecomastia. The subjects have erections, ejaculations and a libido directed towards females. They have decreased body hair, a scant to absent beard, no temporal hair line recession and a small prostate. Testicular biopsy reveals a normal testis. The mean plasma T levels in affected adults are significantly higher, and the mean plasma DHT levels are significantly lower when compared to those in normal subjects. The plasma T:DHT ratios range from 35 to 84 compared to 8 to 16 in normal subjects. After the administration of hCG, the T:DHT ratios in affected male children range from 74 to 162 compared to 3 to 26 in the control subjects. In affected adults, mean plasma LH and FSH levels are significantly higher than in normal subjects. In the affected subjects, the metabolic clearance rates of T and DHT are normal, but the conversion ratio of T to DHT is less than 1 per cent. The endogenous mean urinary E:A and E-OH:A-OH ratios, and the urinary E:A and E-OH:A-OH ratios after the infusion of radioactive T are significantly higher than in normal males. Inheritance is autosomal recessive with some sibling sisters showing the same biochemical defect, and obligate carrier parents showing an intermediate defect. These data support our thesis that the defect in these male pseudohermaphrodites is secondary to decreased steroid delta 4-5 alpha-reductase activity. The affected subjects provide a clinical model for delineating the roles of T and DHT in sexual differentiation and development. This entity also demonstrates an inherited disorder of steroid metabolism in which the basic enzyme deficiency resides in the target tissues.

Testicular feminization syndrome: current clinical considerations

The testicular feminization syndrome (TFS) in its complete form results in total feminization due to a nuclear inaction of androgens, and the female role should be supported with postpubertal orchiectomy to avoid the risk of malignancy. Incomplete forms of the syndrome (ITFS) include Type I n which some degree of masculinization may be observed, prompting earlier gonadectomy, and Type II or pseudovaginal perineoscrotal hypospadias (PPSH) which is always characterized by pubertal masculinization, necessitating management and support of these patients as males. Other intersex abnormalities which must be differentiated include true hermaphroditism, the Swyer syndrome, males with 17-ketosteroid reductase deficiency, and Reifenstein's syndrome.

Genetic and hormonal control of male sexual differentiation

Phenotypic sexual differentiation during embryogenesis is a complex process involving the action of at least 18 genes. These genes regulate gonadal differentiation, gonadal hormone formation, and in the male the cellular action of three necessary hormones, namely mullerian regression factor, testosterone, and dihydrotestosterone. Analysis of two of the mutations affecting sexual development is consistent with the thesis that the two androgens testosterone and dihydrotestosterone have separate and specific roles in virilization of the male urogenital tract, testosterone stimulating wolffian duct development and dihydrotestosterone mediating development of the urogenital sinus and external genitalia. In the disorder familial incomplete male pseudohermphroditism, type 2, deficient dihydrotestosterone formation is associated with a selective failure of virilization of the urogenital sinus and external genitalia, whereas the wolffian duct derivatives develop normally. On the other hand, in the testicular feminization syndrome there is a complete failure in the development of the male phenotype, indicating that the primary defect involves an abnormality in some biochemical step that is common to the action of both androgens. Evidence from studies in the submandibular gland of the mouse with testicular feminization suggest that the fundamental defect lies in the translocation and/or nuclear binding of the cytoplasmic androgen receptor. It remains to be proven whether these events in the postnatal, sexually dimorphic submandibular gland of the testicular feminization mouse reflect prenatal events occurring in the urogenital tissues during embryogenesis.