{"id":4422439,"date":"2025-01-11T19:04:30","date_gmt":"2025-01-12T01:04:30","guid":{"rendered":"https:\/\/myendoconsult.com\/learn\/topics\/disorders-of-sex-development\/"},"modified":"2025-01-13T07:02:04","modified_gmt":"2025-01-13T13:02:04","slug":"disorders-of-sex-development","status":"publish","type":"oen_topic","link":"https:\/\/myendoconsult.com\/learn\/topics\/disorders-of-sex-development\/","title":{"rendered":"Disorders of Sex Development"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">DISORDERS OF SEX DEVELOPMENT (DSD)<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Classification of DSD<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Definition<\/strong>: Congenital discrepancies between external genitalia and gonadal\/chromosomal sex.<\/li>\n\n\n\n<li><strong>Prevalence<\/strong>: Ambiguous genitalia in ~1:4000 births.<\/li>\n\n\n\n<li><strong>Three Main Categories<\/strong>:\n<ol class=\"wp-block-list\">\n<li><strong>Sex Chromosome DSD<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/myendoconsult.com\/learn\/topics\/turner-syndrome\/\"  data-wpil-monitor-id=\"351\">Turner syndrome<\/a> (45,X)<\/strong><\/li>\n\n\n\n<li><strong><a href=\"https:\/\/myendoconsult.com\/learn\/topics\/klinefelter-syndrome\/\"  data-wpil-monitor-id=\"352\">Klinefelter syndrome<\/a> (47,XXY)<\/strong><\/li>\n\n\n\n<li><strong>Mixed gonadal dysgenesis (45,X\/46,XY)<\/strong><\/li>\n\n\n\n<li><strong>Chimerism (46,XX\/46,XY)<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>46,XX DSD (Virilized XX Female)<\/strong>\n<ul class=\"wp-block-list\">\n<li>Disorders of gonadal development (gonadal dysgenesis, ovotesticular DSD, testicular DSD)<\/li>\n\n\n\n<li>Androgen excess (fetal or maternal in origin)<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>46,XY DSD (Undervirilized XY Male)<\/strong>\n<ul class=\"wp-block-list\">\n<li>Disorders of testis development (complete\/partial gonadal dysgenesis, ovotesticular DSD, testis regression)<\/li>\n\n\n\n<li>Disorders of androgen synthesis or action (e.g., CAH, LH receptor mutations, 5\u03b1-reductase 2 deficiency)<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Components of Sex Determination<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Chromosomal Sex<\/strong> (e.g., 46,XX or 46,XY)<\/li>\n\n\n\n<li><strong>Phenotypic Sex<\/strong> (external genitalia: male or female)<\/li>\n\n\n\n<li><strong>Gonadal Sex<\/strong> (presence of ovaries or testes)<\/li>\n\n\n\n<li><strong>Psychosocial Development<\/strong> (gender identity, gender role, sexual orientation).<\/li>\n<\/ol>\n\n\n\n<p><strong>DSD<\/strong> = congenital disorder in which the development of chromosomal, phenotypic, or gonadal sex is atypical.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">CHROMOSOMAL SEX<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Usually<\/strong>: 46,XX (female), 46,XY (male).<\/li>\n\n\n\n<li><strong>Aneuploidy<\/strong>: Meiotic nondisjunction \u2192 gain\/loss of sex chromosome (e.g., 47,XXY [Klinefelter], 45,X [Turner]).<\/li>\n\n\n\n<li><strong>Mosaicism<\/strong>: Mitotic nondisjunction \u2192 45,X\/46,XX or 45,X\/46,XY, etc.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">GONADAL SEX<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Determined by <strong>presence of ovaries or testes<\/strong>.<\/li>\n\n\n\n<li><strong>Y chromosome<\/strong> has <strong>SRY<\/strong> (testis-determining gene); it + <strong>SOX9<\/strong> \u2192 testis development, AMH production \u2192 m\u00fcllerian duct regression.<\/li>\n\n\n\n<li><strong>Ovarian development<\/strong>: Absence of SRY\/SOX9 expression and lack of AMH secretion \u2192 normal female internal duct formation.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">PHENOTYPIC SEX<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Male Differentiation<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Sertoli cells<\/strong>: Produce <strong>AMH<\/strong> \u2192 m\u00fcllerian duct regression (uterus, fallopian tubes, upper vagina).\n<ul class=\"wp-block-list\">\n<li>If AMH or its receptor is defective \u2192 Persistent M\u00fcllerian Duct Syndrome (PMDS).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Leydig cells<\/strong>: Secrete androgens (testosterone) by 9th week.\n<ul class=\"wp-block-list\">\n<li>Stimulated first by hCG (1st\u20132nd trimesters), then by fetal LH (3rd trimester).<\/li>\n\n\n\n<li>Testosterone stabilizes wolffian duct structures (vas deferens, epididymis, seminal vesicles).<\/li>\n\n\n\n<li><strong>DHT<\/strong> (via 5\u03b1-reductase type 2) \u2192 <a href=\"https:\/\/myendoconsult.com\/learn\/male-external-genitalia-exam\/\"  data-wpil-monitor-id=\"356\">male external genitalia<\/a> (penis, scrotum).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Testicular Descent<\/strong>: Two stages\u2014transabdominal (~12 wks) and transinguinal (androgen + LH dependent).<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Female Differentiation<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>M\u00fcllerian ducts<\/strong> \u2192 uterus, upper vagina, fallopian tubes in absence of testicular factors.<\/li>\n\n\n\n<li><strong>Wolffian ducts<\/strong> regress without local testosterone.<\/li>\n\n\n\n<li><strong>External Genitalia<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Genital tubercle \u2192 clitoris.<\/li>\n\n\n\n<li>Urogenital folds \u2192 labia minora.<\/li>\n\n\n\n<li>Urogenital swellings \u2192 labia majora.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Ovarian estrogen is minimal in fetus; female ductal development does not require gonadal hormones.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Psychosocial Development<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Gender identity, gender role, sexual orientation<\/strong> are influenced by prenatal hormone levels + postnatal environment.<\/li>\n\n\n\n<li>Example: <strong>Complete <a href=\"https:\/\/myendoconsult.com\/learn\/androgen-insensitivity-syndrome\/\"  data-wpil-monitor-id=\"353\">Androgen Insensitivity Syndrome<\/a> (CAIS)<\/strong> (46,XY) \u2192 typical female psychosocial development.<\/li>\n\n\n\n<li>Some changes may occur at puberty (e.g., 5\u03b1-reductase deficiency).<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Klinefelter Syndrome (47,XXY)<\/strong>: <\/li>\n\n\n\n<li><strong>Turner Syndrome (45,X)<\/strong>:<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">Mixed Gonadal Dysgenesis (45,X\/46,XY)<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Phenotypic Range<\/strong>: From typical female external genitalia to ambiguous or typical male.<\/li>\n\n\n\n<li><strong>Gonadal Range<\/strong>: Streak gonads to normal testes.<\/li>\n\n\n\n<li><strong>Uterus<\/strong> may be present if AMH is insufficient \u2192 persistent m\u00fcllerian structures.<\/li>\n\n\n\n<li><strong>Management<\/strong>:\n<ul class=\"wp-block-list\">\n<li>If raised as girl (with minimal virilization), remove dysgenic gonads (high tumor risk), then start estrogen therapy at puberty.<\/li>\n\n\n\n<li>If raised as boy (hypospadias, partial testis function), then hypospadias repair, orchiopexy if needed, possibly testosterone at puberty.<\/li>\n\n\n\n<li>In very ambiguous cases, complex decisions are made with a multidisciplinary team.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Chimerism (46,XX\/46,XY)<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Results from double fertilization or ovum fusion.<\/li>\n\n\n\n<li>Can lead to <strong>ovotesticular DSD<\/strong> (true hermaphroditism).<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">46,XX DISORDERS OF SEX DEVELOPMENT<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>(Virilized XX Female)<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Main Causes<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Gonadal Dysgenesis<\/strong> (primary ovarian failure, minimal estrogen).<\/li>\n\n\n\n<li><strong>Ovotesticular DSD<\/strong> (ovary + testis tissue).<\/li>\n\n\n\n<li><strong>Testicular DSD<\/strong> (SRY translocation, SOX9 duplication).<\/li>\n\n\n\n<li><strong>Androgen Excess<\/strong> (most common):\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/myendoconsult.com\/learn\/topics\/congenital-adrenal-hyperplasia-cah\/\"  data-wpil-monitor-id=\"354\">Congenital Adrenal Hyperplasia<\/a> (CAH)<\/strong>, typically 21-hydroxylase deficiency.<\/li>\n\n\n\n<li><strong>Gestational hyperandrogenism<\/strong> (e.g., maternal androgen-secreting tumor, theca-lutein cysts, placental aromatase deficiency).<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">Congenital Adrenal Hyperplasia<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Most frequent cause of <strong>virilized XX newborns<\/strong> (46,XX DSD).<\/li>\n\n\n\n<li>Usually 21-hydroxylase deficiency.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Ovotesticular DSD (True Hermaphroditism)<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Presence of both testicular and ovarian tissue<\/strong> in one or both gonads.<\/li>\n\n\n\n<li>Typically 46,XX karyotype (~60%), less commonly 46,XX\/46,XY chimeric.<\/li>\n\n\n\n<li>Gonads can be: ovotestis on one side + ovary\/testis on other, bilateral ovotestes, or testis on one side + ovary on the other (least common).<\/li>\n\n\n\n<li>External phenotype can vary from near male to near female; many have ambiguous genitalia.<\/li>\n\n\n\n<li>Management: Complex; depends on functional aspects, tumor risk, potential fertility, and desired gender assignment.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">46,XY DISORDERS OF SEX DEVELOPMENT<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>(Undervirilized XY Male)<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Main Causes<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Abnormal Testis Development<\/strong>\n<ul class=\"wp-block-list\">\n<li>Complete or partial gonadal dysgenesis (e.g., Swyer syndrome).<\/li>\n\n\n\n<li>Ovotesticular DSD.<\/li>\n\n\n\n<li>Testis regression (e.g., vanished testis syndrome).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Impaired Androgen Synthesis<\/strong>\n<ul class=\"wp-block-list\">\n<li>CAH due to 17\u03b1-hydroxylase deficiency, 3\u03b2-HSD deficiency, P450scc deficiency.<\/li>\n\n\n\n<li>LH receptor defects (Leydig cell hypoplasia).<\/li>\n\n\n\n<li>5\u03b1-reductase 2 deficiency \u2192 inadequate DHT \u2192 undervirilized external genitalia.<\/li>\n\n\n\n<li>17\u03b2-HSD type 3 deficiency (most common testosterone synthesis defect).<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Impaired Androgen Action<\/strong>\n<ul class=\"wp-block-list\">\n<li><strong>Androgen Insensitivity Syndrome (AIS)<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Complete (CAIS) \u2192 phenotypic female with undescended testes, no uterus, no pubic\/axillary hair.<\/li>\n\n\n\n<li>Partial (PAIS) \u2192 ambiguous or predominantly male or female with some undervirilization.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Mutations in AR gene; range of clinical phenotypes.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">Clinical Presentation<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ranges from ambiguous genitalia, micropenis, hypospadias to near-female external appearance.<\/li>\n\n\n\n<li>Gonads may be undescended (risk of tumors).<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">EVALUATION AND TREATMENT OF DSD<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Initial Workup<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>History<\/strong>: Family occurrences, maternal exposures, prior pregnancies.<\/li>\n\n\n\n<li><strong>Physical Exam<\/strong>: External genitalia measurements (phallus size, fused labial\/scrotal tissue), presence of gonads in labia\/inguinal canal, TANNER staging if older.<\/li>\n\n\n\n<li><strong>Laboratory<\/strong>:\n<ul class=\"wp-block-list\">\n<li>Serum electrolytes (to rule out salt-wasting CAH).<\/li>\n\n\n\n<li>17-hydroxyprogesterone, cortisol, DHEA, androstenedione, testosterone, LH, FSH, TSH.<\/li>\n\n\n\n<li>\u00b1 \u03b2-hCG, \u03b1-fetoprotein if germ cell tumor suspected.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Karyotype<\/strong> + <strong>FISH<\/strong> for SRY gene.<\/li>\n\n\n\n<li><strong>Imaging<\/strong>: Pelvic and abdominal ultrasound \u2192 uterus\/vagina presence, gonad location\/size.<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">Management Implications<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Determine underlying cause<\/strong>: Key for deciding sex assignment, surgical interventions, hormone treatments, tumor risk.<\/li>\n\n\n\n<li><strong>Sex Assignment<\/strong>: Typically guided by the probability of future gonadal function, potential fertility, surgical complexity, and psychosocial considerations.<\/li>\n\n\n\n<li><strong>Hormone Therapy<\/strong>: E.g., glucocorticoid for CAH, GnRH analog for central <a href=\"https:\/\/myendoconsult.com\/learn\/topics\/precocious-puberty\/\"  data-wpil-monitor-id=\"355\">precocious puberty<\/a> if relevant.<\/li>\n\n\n\n<li><strong>Surgical<\/strong>: Gonadectomy of dysgenic gonads (tumor risk), correction of ambiguous genitalia (urogenital sinus anomalies), orchiopexy for undescended testis, or hypospadias repair.<\/li>\n\n\n\n<li><strong>Long-Term Follow-Up<\/strong>: Involves endocrinologists, surgeons, geneticists, psychologists for counseling on fertility, psychosocial identity, risk of neoplasms, etc.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>DISORDERS OF SEX DEVELOPMENT (DSD) Classification of DSD Components of Sex Determination DSD = congenital disorder in which the development of chromosomal, phenotypic, or gonadal sex is atypical. CHROMOSOMAL SEX GONADAL SEX PHENOTYPIC SEX Male Differentiation Female Differentiation Psychosocial Development SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT Mixed Gonadal Dysgenesis (45,X\/46,XY) Chimerism (46,XX\/46,XY) 46,XX DISORDERS OF [&hellip;]<\/p>\n","protected":false},"featured_media":0,"template":"","oen_topic_chapter":[685],"class_list":["post-4422439","oen_topic","type-oen_topic","status-publish","hentry","oen_topic_chapter-reproductive-disorders","post-wrapper","thrv_wrapper"],"_links":{"self":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422439","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic"}],"about":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/types\/oen_topic"}],"version-history":[{"count":5,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422439\/revisions"}],"predecessor-version":[{"id":4422874,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic\/4422439\/revisions\/4422874"}],"wp:attachment":[{"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/media?parent=4422439"}],"wp:term":[{"taxonomy":"oen_topic_chapter","embeddable":true,"href":"https:\/\/myendoconsult.com\/learn\/wp-json\/wp\/v2\/oen_topic_chapter?post=4422439"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}