Congenital Disorders of Sexual Development

Overview of Sex Development

Definition

Disorders of sexual development are a group of conditions characterized by atypical sexual development in an individual, involving abnormalities in the structure and/or function of both the internal reproductive organs and/or external genitalia.

Overview of typical sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria development

• Chromosomal sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria → determines gonadal sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria → determines phenotypic sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria
• Up until 6 weeks of gestation, sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria development is identical and nonbinary. The developing structures include:
  • Nonbinary, bipotent, undifferentiated gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types
  • Wolffian and Müllerian ducts (both are present in both sexes initially)
  • Urogenital sinus Urogenital Sinus Congenital Malformations of the Female Reproductive System
  • The genital tubercle Genital Tubercle Development of the Urogenital System, genital swellings Genital swellings Development of the Urogenital System, and genital folds Genital folds Development of the Urogenital System 
• The genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure present at fertilization Fertilization To undergo fertilization, the sperm enters the uterus, travels towards the ampulla of the fallopian tube, and encounters the oocyte. The zona pellucida (the outer layer of the oocyte) deteriorates along with the zygote, which travels towards the uterus and eventually forms a blastocyst, allowing for implantation to occur. Fertilization and First Week will determine how the developing bipotent gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types differentiate (e.g., into a testis or an ovary).
• The developing gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types will then secrete hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types:
  • The presence and/or absence of specific hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types will determine how the remaining structures differentiate.
  • In general, female organs and structures are the “default” phenotype Phenotype The complete genetic complement contained in the DNA of a set of chromosomes in a human. The length of the human genome is about 3 billion base pairs. Basic Terms of Genetics if specific genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure and hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types are not present to stimulate male differentiation.

Sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria organs and characteristics

• Gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types develop based on the karyotype Karyotype The full set of chromosomes presented as a systematized array of metaphase chromosomes from a photomicrograph of a single cell nucleus arranged in pairs in descending order of size and according to the position of the centromere. Congenital Malformations of the Female Reproductive System/ genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure that are present.
  • Testes Testes Gonadal Hormones: 
    • Develop when sex-determining region of the Y chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics (SRY gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics) is present
    • Secrete testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens and anti-Müllerian hormone ( AMH AMH A glycoprotein that causes regression of mullerian ducts. It is produced by sertoli cells of the testes. In the absence of this hormone, the mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent mullerian duct, a form of male pseudohermaphroditism. Primary Amenorrhea)
  • Ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy develop when the X chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics is present and/or the SRY is absent. 
  • Ovotestis: a gonad containing both ovarian and testicular tissue found in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with true hermaphroditism True hermaphroditism True hermaphroditism, or ovotesticular disorder of sexual development (ODSD), is characterized by the presence of an ovotesticular gonad that contains both ovarian and testicular elements. Individuals are usually born with ambiguous genitalia, but the diagnosis is rarely confirmed before puberty. The most common karyotype is 46,XX, and less often, 46,XY can be identified. True Hermaphroditism
• Wolffian structures differentiate from the Wolffian (mesonephric) ducts in the presence of testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens:
  • Epididymis Epididymis The convoluted cordlike structure attached to the posterior of the testis. Epididymis consists of the head (caput), the body (corpus), and the tail (cauda). A network of ducts leaving the testis joins into a common epididymal tubule proper which provides the transport, storage, and maturation of spermatozoa. Testicles: Anatomy
  • Vas deferens Vas Deferens The excretory duct of the testes that carries spermatozoa. It rises from the scrotum and joins the seminal vesicles to form the ejaculatory duct. Testicles: Anatomy
  • Seminal vesicles Seminal vesicles A saclike, glandular diverticulum on each ductus deferens in male vertebrates. It is united with the excretory duct and serves for temporary storage of semen.
  • Ejaculatory ducts Ejaculatory Ducts Paired ducts in the human male through which semen is ejaculated into the urethra.
• Müllerian structures differentiate from the Müllerian (paramesonephric) ducts when AMH AMH A glycoprotein that causes regression of mullerian ducts. It is produced by sertoli cells of the testes. In the absence of this hormone, the mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent mullerian duct, a form of male pseudohermaphroditism. Primary Amenorrhea is absent:
  • Uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy
  • Fallopian tubes Fallopian tubes The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The fallopian tubes receive an ovum after ovulation and help move it and/or a fertilized embryo toward the uterus via ciliated cells lining the tubes and peristaltic movements of its smooth muscle. Uterus, Cervix, and Fallopian Tubes: Anatomy
  • Upper ⅓ of the vagina Vagina The vagina is the female genital canal, extending from the vulva externally to the cervix uteri internally. The structures have sexual, reproductive, and urinary functions and a rich blood supply, mainly arising from the internal iliac artery. Vagina, Vulva, and Pelvic Floor: Anatomy
• External genitalia develop from the undifferentiated genital tubercle Genital Tubercle Development of the Urogenital System, genital swelling Swelling Inflammation, and genital folds Genital folds Development of the Urogenital System based on the presence or absence of testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens.
  • Male: testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens → penis Penis The penis is the male organ of copulation and micturition. The organ is composed of a root, body, and glans. The root is attached to the pubic bone by the crura penis. The body consists of the 2 parallel corpora cavernosa and the corpus spongiosum. The glans is ensheathed by the prepuce or foreskin. Penis: Anatomy and scrotum Scrotum A cutaneous pouch of skin containing the testicles and spermatic cords. Testicles: Anatomy
  • Female: lack of testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens → clitoris Clitoris An erectile structure homologous with the penis, situated beneath the anterior labial commissure, partially hidden between the anterior ends of the labia minora. Vagina, Vulva, and Pelvic Floor: Anatomy, labia majora Labia majora Vagina, Vulva, and Pelvic Floor: Anatomy, labia minora Labia minora Vagina, Vulva, and Pelvic Floor: Anatomy
• Secondary sexual characteristics Secondary Sexual Characteristics Precocious Puberty develop based on the hormonal milieu at puberty Puberty Puberty is a complex series of physical, psychosocial, and cognitive transitions usually experienced by adolescents (11-19 years of age). Puberty is marked by a growth in stature and the development of secondary sexual characteristics, achievement of fertility, and changes in most body systems. Puberty.
  • Androgenic characteristics: due to the presence of testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens and/or dihydrotestosterone Dihydrotestosterone A potent androgenic metabolite of testosterone. It is produced by the action of the enzyme 3-oxo-5-alpha-steroid 4-dehydrogenase. Gonadal Hormones ( DHT DHT A potent androgenic metabolite of testosterone. It is produced by the action of the enzyme 3-oxo-5-alpha-steroid 4-dehydrogenase. Gonadal Hormones)
    • Pubic and axillary hair
    • Facial and body hair in an androgenic distribution and quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement (dark and coarse)
    • Deepening of the voice
    • ↑ Muscle mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast
  • Estrogenic characteristics result from the presence of estrogen Estrogen Compounds that interact with estrogen receptors in target tissues to bring about the effects similar to those of estradiol. Estrogens stimulate the female reproductive organs, and the development of secondary female sex characteristics. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds. Ovaries: Anatomy:
    • Breast development
    • Wider hips

Typical male development

Male development begins due to the presence of the sex-determining region of the Y chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics (SRY gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics).

• SRY gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics → produces SRY protein SRY protein Development of the Urogenital System (also known as testis-determining factor):
  • Stimulates the differentiation of the bipotent gonad into testes Testes Gonadal Hormones 
  • Stimulates development of:
    • Seminiferous tubules Seminiferous Tubules The convoluted tubules in the testis where sperm are produced (spermatogenesis) and conveyed to the rete testis. Spermatogenic tubules are composed of developing germ cells and the supporting sertoli cells. Testicles: Anatomy
    • Leydig cells Leydig Cells Steroid-producing cells in the interstitial tissue of the testis. They are under the regulation of pituitary hormones; luteinizing hormone; or interstitial cell-stimulating hormone. Testosterone is the major androgen (androgens) produced. Testicles: Anatomy
    • Sertoli cells Sertoli Cells Supporting cells projecting inward from the basement membrane of seminiferous tubules. They surround and nourish the developing male germ cells and secrete androgen-binding protein and hormones such as anti-mullerian hormone. The tight junctions of sertoli cells with the spermatogonia and spermatocytes provide a blood-testis barrier. Testicles: Anatomy
  • Suppresses the differentiation of ovaries Ovaries Ovaries are the paired gonads of the female reproductive system that contain haploid gametes known as oocytes. The ovaries are located intraperitoneally in the pelvis, just posterior to the broad ligament, and are connected to the pelvic sidewall and to the uterus by ligaments. These organs function to secrete hormones (estrogen and progesterone) and to produce the female germ cells (oocytes). Ovaries: Anatomy
• Testes Testes Gonadal Hormones secrete:
  • AMH AMH A glycoprotein that causes regression of mullerian ducts. It is produced by sertoli cells of the testes. In the absence of this hormone, the mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent mullerian duct, a form of male pseudohermaphroditism. Primary Amenorrhea
  • Testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens
  • DHT DHT A potent androgenic metabolite of testosterone. It is produced by the action of the enzyme 3-oxo-5-alpha-steroid 4-dehydrogenase. Gonadal Hormones
• The above hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types cause:
  • Stimulation of the Wolffian ducts Wolffian ducts A pair of excretory ducts of the middle kidneys of an embryo, also called mesonephric ducts. In higher vertebrates, wolffian ducts persist in the male forming vas deferens, but atrophy into vestigial structures in the female. Primary Amenorrhea (around the 8th week) to differentiate into the epididymis Epididymis The convoluted cordlike structure attached to the posterior of the testis. Epididymis consists of the head (caput), the body (corpus), and the tail (cauda). A network of ducts leaving the testis joins into a common epididymal tubule proper which provides the transport, storage, and maturation of spermatozoa. Testicles: Anatomy, vas deferens Vas Deferens The excretory duct of the testes that carries spermatozoa. It rises from the scrotum and joins the seminal vesicles to form the ejaculatory duct. Testicles: Anatomy, seminal vesicles Seminal vesicles A saclike, glandular diverticulum on each ductus deferens in male vertebrates. It is united with the excretory duct and serves for temporary storage of semen. , and ejaculatory ducts Ejaculatory Ducts Paired ducts in the human male through which semen is ejaculated into the urethra.
  • Regression Regression Corneal Abrasions, Erosion, and Ulcers of the Müllerian ducts
  • Differentiation of the prostate Prostate The prostate is a gland in the male reproductive system. The gland surrounds the bladder neck and a portion of the urethra. The prostate is an exocrine gland that produces a weakly acidic secretion, which accounts for roughly 20% of the seminal fluid. and external genitalia 
• The process of differentiation is largely completed by 12 weeks of gestation.

Typical female development

• Development of the ovary from the bipotent gonad requires:
  • Absence of the SRY (preventing differentiation into testes Testes Gonadal Hormones)
  • Presence of several genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure found on chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 1, including:
    • WNT4 
    • R spondin 1 (Rspo1)
  • Begins around 10 weeks of development
• Differentiation and development of the Müllerian ducts and external genitalia occur when testicular androgens Androgens Androgens are naturally occurring steroid hormones responsible for development and maintenance of the male sex characteristics, including penile, scrotal, and clitoral growth, development of sexual hair, deepening of the voice, and musculoskeletal growth. Androgens and Antiandrogens and AMH AMH A glycoprotein that causes regression of mullerian ducts. It is produced by sertoli cells of the testes. In the absence of this hormone, the mullerian ducts develop into structures of the female reproductive tract. In males, defects of this hormone result in persistent mullerian duct, a form of male pseudohermaphroditism. Primary Amenorrhea are absent.
• Embryos develop in the “female hormonal environment” within their mother; thus, it is unclear whether hormones Hormones Hormones are messenger molecules that are synthesized in one part of the body and move through the bloodstream to exert specific regulatory effects on another part of the body. Hormones play critical roles in coordinating cellular activities throughout the body in response to the constant changes in both the internal and external environments. Hormones: Overview and Types produced by the fetus are required for their development.

Summary of Common Disorders of Sexual Development

Principles of Diagnosis

The differential diagnosis for disorders of sexual development typically includes many of the conditions listed above. The general diagnostic approach to help determine the appropriate diagnosis is listed below.

Exam

• Genital examination:
  • Ambiguous genitalia Ambiguous Genitalia Primary Amenorrhea is likely due to ↑ testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens/ DHT DHT A potent androgenic metabolite of testosterone. It is produced by the action of the enzyme 3-oxo-5-alpha-steroid 4-dehydrogenase. Gonadal Hormones in individuals without SRY (e.g., 46,XX) or ↓ testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens in individuals with SRY (e.g., 46,XY)
  • Assess the size and descent of testes Testes Gonadal Hormones.
• Internal pelvic examination on phenotypic females:
  • Is a cervix Cervix The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Externally, the cervix is lined by stratified squamous cells; however, the cervical canal is lined by columnar epithelium. Uterus, Cervix, and Fallopian Tubes: Anatomy visible?
  • Is the uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy palpable?
• Assessment of secondary sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria characteristics in adolescents/adults:
  • Breast development = estrogen Estrogen Compounds that interact with estrogen receptors in target tissues to bring about the effects similar to those of estradiol. Estrogens stimulate the female reproductive organs, and the development of secondary female sex characteristics. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds. Ovaries: Anatomy present
  • Pubic and axillary hair = testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens present
  • Facial/body hair, deepening of the voice = testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens present
• Look for findings associated with specific syndromes (e.g., webbed neck Webbed neck Turner Syndrome in Turner syndrome Turner syndrome Turner syndrome is a genetic condition affecting women, in which 1 X chromosome is partly or completely missing. The classic result is the karyotype 45,XO with a female phenotype. Turner syndrome is associated with decreased sex hormone levels and is the most common cause of primary amenorrhea. Turner Syndrome).

Laboratory

• Karyotype Karyotype The full set of chromosomes presented as a systematized array of metaphase chromosomes from a photomicrograph of a single cell nucleus arranged in pairs in descending order of size and according to the position of the centromere. Congenital Malformations of the Female Reproductive System with FISH FISH A type of in situ hybridization in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei. Chromosome Testing to assess the presence or absences of the SRY gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics
• Testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens: 
  • Decreases in Kallman, Swyer, and Klinefelter syndromes
  • Increases or is normal in androgen insensitivity syndrome Androgen insensitivity syndrome Androgen insensitivity syndrome (AIS) is an X-linked recessive condition in which a genetic mutation affects the function of androgen receptors, resulting in complete (CAIS), partial (PAIS), or mild (MAIS) resistance to testosterone. All individuals with AIS have a 46,XY karyotype; however, phenotypes vary and include phenotypic female, virilized female, undervirilized male, and phenotypic male individuals. Androgen Insensitivity Syndrome ( AIS AIS Scoliosis), 5α-reductase deficiency, aromatase Aromatase An enzyme that catalyzes the desaturation (aromatization) of the ring a of C19 androgens and converts them to C18 estrogens. In this process, the 19-methyl is removed. This enzyme is membrane-bound, located in the endoplasmic reticulum of estrogen-producing cells of ovaries, placenta, testes, adipose, and brain tissues. Aromatase is encoded by the cyp19 gene, and functions in complex with NADPH-ferrihemoprotein reductase in the cytochrome p450 system. Adipose Tissue: Histology deficiency, and congenital adrenal hyperplasia Congenital adrenal hyperplasia Congenital adrenal hyperplasia (CAH) consists of a group of autosomal recessive disorders that cause a deficiency of an enzyme needed in cortisol, aldosterone, and androgen synthesis. The most common subform of CAH is 21-hydroxylase deficiency, followed by 11β-hydroxylase deficiency. Congenital Adrenal Hyperplasia
• DHT DHT A potent androgenic metabolite of testosterone. It is produced by the action of the enzyme 3-oxo-5-alpha-steroid 4-dehydrogenase. Gonadal Hormones: 
  • Decreases with 5α-reductase deficiency 
  • Increases in AIS AIS Scoliosis
• Follicle stimulating hormone ( FSH FSH A major gonadotropin secreted by the adenohypophysis. Follicle-stimulating hormone stimulates gametogenesis and the supporting cells such as the ovarian granulosa cells, the testicular sertoli cells, and leydig cells. Fsh consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle) and luteinizing hormone ( LH LH A major gonadotropin secreted by the adenohypophysis. Luteinizing hormone regulates steroid production by the interstitial cells of the testis and the ovary. The preovulatory luteinizing hormone surge in females induces ovulation, and subsequent luteinization of the follicle. Luteinizing hormone consists of two noncovalently linked subunits, alpha and beta. Within a species, the alpha subunit is common in the three pituitary glycoprotein hormones (TSH, LH, and FSH), but the beta subunit is unique and confers its biological specificity. Menstrual Cycle): 
  • Decrease in Kallmann syndrome Kallmann syndrome Kallmann syndrome (KS), also called olfacto-genital syndrome, is a genetic condition that causes hypogonadotropic hypogonadism due to decreased secretion of gonadotropin-releasing hormone (GnRH) by the hypothalamus. The lack of sex hormones results in impaired pubertal development. Kallmann Syndrome (due to ↓ gonadotropin-releasing hormone Gonadotropin-releasing hormone A decapeptide that stimulates the synthesis and secretion of both pituitary gonadotropins, luteinizing hormone and follicle stimulating hormone. Gnrh is produced by neurons in the septum preoptic area of the hypothalamus and released into the pituitary portal blood, leading to stimulation of gonadotrophs in the anterior pituitary gland. Puberty (GnRH))
  • Increase in 46,XX gonadal dysgenesis 46,XX Gonadal Dysgenesis 46,XX gonadal dysgenesis is a disorder present in individuals who are phenotypic females with normal karyotypes of 46,XX and who have streak gonads with no functional ovarian tissue. It is also called “pure gonadal dysgenesis” to differentiate these patients from those who present with the phenotype of Turner’s syndrome. 46,XX Gonadal Dysgenesis and Swyer syndrome Swyer syndrome Swyer syndrome is a disorder of sex development caused by a defect in the SRY gene on chromosome Y. The syndrome is characterized by complete testicular dysgenesis in an individual who has a 46,XY karyotype and is phenotypically female. Swyer Syndrome (normal GnRH function with non-responsive gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types)
• 17-Hydroxyprogesterone: ↑ in congenital adrenal hyperplasia Congenital adrenal hyperplasia Congenital adrenal hyperplasia (CAH) consists of a group of autosomal recessive disorders that cause a deficiency of an enzyme needed in cortisol, aldosterone, and androgen synthesis. The most common subform of CAH is 21-hydroxylase deficiency, followed by 11β-hydroxylase deficiency. Congenital Adrenal Hyperplasia

Imaging

Abdominal pelvic ultrasound to assess the internal organs:

• Presence or absence of a uterus Uterus The uterus, cervix, and fallopian tubes are part of the internal female reproductive system. The uterus has a thick wall made of smooth muscle (the myometrium) and an inner mucosal layer (the endometrium). The most inferior portion of the uterus is the cervix, which connects the uterine cavity to the vagina. Uterus, Cervix, and Fallopian Tubes: Anatomy
• Assessment of the gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types

Consider imaging of the kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy and urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy, as abnormalities in the reproductive organs are frequently associated with renal/urinary anomalies.

Principles of Management

• Factors affecting management:
  • Age of presentation (infant, adolescent, versus adult)
  • Gender identity Gender identity A person’s concept of self as being male and masculine or female and feminine, or ambivalent, based in part on physical characteristics, parental responses, and psychological and social pressures. It is the internal experience of gender role. Sexual Physiology and preferences of the patient
  • Hormone status
• Psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy/counseling: All patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship (and potentially family members) should be referred for therapy.
• Hormone replacement therapy Hormone Replacement Therapy Hormone replacement therapy (HRT) is used to treat symptoms associated with female menopause and in combination to suppress ovulation. Risks and side effects include uterine bleeding, predisposition to cancer, breast tenderness, hyperpigmentation, migraine headaches, hypertension, bloating, and mood changes. Noncontraceptive Estrogen and Progestins ( HRT HRT Hormone replacement therapy (HRT) is used to treat symptoms associated with female menopause and in combination to suppress ovulation. Risks and side effects include uterine bleeding, predisposition to cancer, breast tenderness, hyperpigmentation, migraine headaches, hypertension, bloating, and mood changes. Noncontraceptive Estrogen and Progestins) may be indicated in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with hormonal deficiencies (e.g., testosterone Testosterone A potent androgenic steroid and major product secreted by the leydig cells of the testis. Its production is stimulated by luteinizing hormone from the pituitary gland. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol. Androgens and Antiandrogens and/or estrogen Estrogen Compounds that interact with estrogen receptors in target tissues to bring about the effects similar to those of estradiol. Estrogens stimulate the female reproductive organs, and the development of secondary female sex characteristics. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds. Ovaries: Anatomy).
• Surgery:
  • Abnormal gonads Gonads The gamete-producing glands, ovary or testis. Hormones: Overview and Types, especially gonadoblastomas and dysgerminomas, pose a high risk for malignancy Malignancy Hemothorax → surgical excision recommended
  • Reconstructive or reassignment surgery