2. CONTENTS of Part 1
1. Development in brief
2. Introduction
3. Classifications
4. Incidence
5. 46 XX DSD
6. 46 XY DSD
3. Normal Sexual Differentiation
GENETIC SEX
GONADAL SEX
SEXUAL
DIFFERENTIATION OF
BRAIN
HORMONE
PRODUCTION AT
PUBERTY
SECONDARY SEXUAL
DEVELOPMENT
HORMONE
PRODUCTION DURING
FETAL DEVELOPMENT
SEXUAL
DIFFERENTIATION OF
EXTERNAL GENITALIA
SEX OF ASSIGNMENT &
REARING
GENDER
IDENTITY
PHENOTYPIC
SEX
10. Urogenital sinus
Female external genitalia
. Lower part of vagina
Mullerian ducts
Female internal genital
Organs
. Most of upper vagina
. Cervix and uterus
. Fallopian tubes
Neutral
Development
Absence of androgen exposure
Female development
11. INTRODUCTION
• DISORDERS OF SEXUAL DEVELOPMENT:
Congenital conditions characterized by atypical development of chromosomal,
gonadal or phenotypic sex.
• INTERSEX
An individual in whom there is discordance between chromosomal, gonadal,
internal genital, and phenotypic sex or the sex of rearing.
• INTERSEXUALITY:
Discordance between any two of the organic sex criteria
• TRANSSEXUALITY:
Discordance between organic sex and psychological sex components.
• TRUE HERMAPHRODITISM:
Has both ovarian & testicular tissue.
• MALE PSEUDOHERMAPHRODITISM:
Has testes, but a female genotype.
• FEMALE PSEUDOHERMAPHRODITISM:
Has ovaries but a masculine genital characteristics.
16. Incidence
• A conservative estimate is that 1 in 2000 children born will be
affected by an intersex condition.
• 90 % of affected babies are due to congenital adrenal hyperplasia
19. TRUE HERMAPHRODITISM
• Ovotesticular DSD
• Mixed ovarian & testicular tissue.
• B/l ovotestes OR an ovotestis &C/l ovary or testis
• Majority 46XX, 7% 46XY, 10-40% Mosaics
• Rt- Testicular tissue, Lt- ovarian tissue
• Cause- translocation of TDF from Y to X
• Int gen- Both
• Ext gen- Ambiguous / male
• Gonadal biopsy is required for confirming diagnosis
21. 46 XX Sex reversal
• Testicular disorder of sexual devp
• Occurs in 1 of every 20,000 males
• Chromosomal sex (46 XX) not consistent with gonadal sex (testes).
• 2 types- Sry positive& Sry negative
• Cause-
90%- Recombination distal short arms of X & Y and transfer of sry from Y to X during male
meiosis.
10%- Sry not detected
• Int genitalia- Testes
• Ext genitalia-
Sry-negative: ambiguous
Sry positive: Normal male but hypogonadism, gynaecomastia, infertility, features of
Klinefelter but have
o Shorter (mean height, 168 cm) & more normal skeletal proportions than Klinefelter’s
patients
o Infertile lack of germ cell elements
22. 46 XX Pure Gonadal Dysgenesis
• Cause- Autosomal etiology (AR)
• Features:
• Normal female external genitalia
• Normal müllerian ducts with absence of wolffian duct structures
• Normal height
• Normal 46 XX
• Bilateral streak gonads elevated serum gonadotropins
(hypergondotropic hypogonadism)
• Sexual infantilism
• Management-
• cyclic hormone replacement with estrogen and progesterone.
• growth is basically normal so GH is not needed
26. Congenital Adrenal Hyperplasia
• >90% - 21 Hydroxylase def
• Basic pathophysiology-
Decrease cortisol stimulate ACTH adrenal hyperplasia
Increase steroid hormone proximal to enzyme block increase androgens
• Time, duration & LEVEL of exposure of androgen determine degree of clitoral
enlargement, labial fusion, urethral & vaginal abnormalities
• <10 wk- no effect, as adrenals not functional, vg & urethra separate
• 10-12 wk- androgens labial fusion, clitoromegaly
• 12-14 wk- limited effect if androgens rise after this
• Female ext gen not completed until 20wks, size of clitoris depends on Level of
androgens
• Ovaries, AMH normal & high local conc not achieved- Wollfian absent
27.
28. 21-Hydroxylase Deficiency
• Most common endocrine cause of neonatal death.
• Two categories:
(1) Classical-
Salt wasters (deficiency of cortisol & aldosterone & with virilization) severe shock
Simple virilizers (patients with virilization, but without circulatory collapse) ambiguous gen
(2) Nonclassical (those without evidence of virilization or salt wasting) hirsutism, Menstrual
irregularities
• 1 in 5000 live births. 2/3rd (75%) Salt wasting 1/3rd (25%) simple virilizing
• Autosomal recessive pattern
• CAUSE: 21-hydroxylase gene ( CYP-21 ) chromosome 6p
1. Non- Reciprocal gene conversions active CYP-21 gene into the inactive gene occur in 65%
to 90% of cases of classic 21-hydroxylase deficiency (i.e., salt wasting and simple virilizing
forms) and in all nonclassic cases
2. Gene deletions are responsible for 10% to 35% of the remainder of mutations that produce
21-hydroxylase deficiency
30. Classical
Salt wasting Simple virilizing
Non classical
Presentation At birth At birth (F)
Neonates, early infancy
(M)
Childhood or early adolescence
Ext genitalia
Puberty
Ambiguous genitalia (F)
(adrenogenital synd)
Adrenal insufficiency (M)
Masculinization of the untreated
female;
Pubic and axillary hair develop
prematurely
Acne
Deepening of voice
Ambiguous genitalia (F)
Young children with
early virilization (M)
Normal
Signs of hyperandrogenism
Precocious puberty
Hirsutism
Menstrual irregularities
Fertility 1.Chronic anovulation
2.Abnormalities of genital anatomy and psychosocial factors
Pregnancy Protective effect of placental aromatase from virilization of
female fetus; increase GDM
Diagnosis 1. 17 OHP levels >3500ng/dl
2. 11 deoxycortisol & 17 α hydroxypregnenolone
3. For confirmation- ACTH stimulation test (>10,000ng/dl)
4. Genotyping cells from CVS
5. Urinary 17-ketosteroids and pregnanentriol are elevated.
6. A pelvic USG for presence of mullerian tissues.
7. Neonatal screening
Not by neonatal screening
Serum 17OHP levels N or
DHEAS - N
1. 17 OHP >82 ng/dl in children
2. Adult women morning levels
<200-exclude CAH
>800- diagnostic
200-800 stimulation test(>1500)
34. 3β Hydroxysteroid Dehydrogenase Deficiency
• Precursor of all steroid hormones.
• 2 types of 3β HSD enzymes-
1. Activity in placenta & peripheral tissues (skin, breast, prostate)
2. Adrenal, ovaries, testes
• Type 2 enzyme defect common.
• Pregnenolone, 17 Pregn, DHEA increased
• Types- Salt wasting & Non salt wasting.
35. • Features- Symptoms of gluco & mineralocorticoid def
• FEMALES: At birth- virilized ext gen;
Late-onset- premture pubarche, signs of hyperandrogenism (mild
clitoromegaly and labial fusion)
• MALE: Incomplete masculinization
• Autosomal recessive inheritance pattern
• Diagnosis-
1. 17 α Hydroxypregnenolone, pregnenolone, DHEA, DHEAS raised
2. Most reliable criteria- serum 17 α HP levels after ACTH stimulation
36. Pregnenlolone
Progesterone
Desoxycorticosterone
Corticosterone
18 OH Corticosterone
Aldosterone
17 OH Pregnenlolone
17 OH Progesterone
11 Desoxycortisol
Cortisol
DeHydroEpiAndrosterone
Androstendione
Testosterone Estradiol
Cholesterol
Desmolase
3 B HSD
21 OH
11 OH
18 OH
Desmolase
3 B HSD 3 B HSD
21 OH
11 OH
Survival is rare due to more proximal enzyme block
Weak Androgen
3 B Hydroxy steroid DH Deficiency:
37. TREATMENT OF CAH
GOALS-
• Classical forms of CAH – provide cortisol , reduce ACTH & prevent androgen effect.
• Mothers- prevent masculinization of female fetus
• Neonates- life saving t/t, prevent virilization
• Children- to permit normal growth & sexual maturation
• Adults- hirsutism, menstrual irreg, infertility
1. PREIMPLANTATION GENETIC DIAGNOSIS IN COUPLES AT RISK- single cell removed from
6-8 cell stage embryo
2. PRENATAL TREATMENT OF MOTHERS AT RISK –
• Dexa upto 1.5mg daily divided doses
• Begin at 4-5 wks but not later than 9wk
• S/e- failure to thrive, psychomotor devp delay (neonate), severe abd striae
hyperglycemia, HTN, GI symp (mother)
• 1 in 4 female fetus benefited. Early CVS , genotyping, sex determination recommended
38.
39. 3. NEONATAL TREATMENT: Present with ambiguity or adrenal
crisis
• Hypotension– 10-20ml/kg 0.9% saline
• Hypoglycemia – 2-4 mg/kg 10% dextrose
• Hyperkalemia- Insulin & glucose
• Withdraw a blood sample for 17OHP etc
• 50-100 mg/m2 iv hydrocort 4 hrly until stable & feeding
normally
• 0.3mg daily fludricortisone & Na Cl 1-3 g daily
4. CHILDREN: to promote growth & decrease sex steroid
production
• Hydrocort 12-18mg/m2
Long acting glucocort can cause early closure of epiphysis
• Fludrocortisone 0.05- 0.2 mg in classical 21 HD
Overt/t- impair growth, Inadeq t/t- stimulate steroidogenesis
40. • Monitor- 3mthly infants, 4-12 mthly in children
• Measure- 17OHP (400-1200ng/dl) , Androstenedione, Plasma
renin activity, growth velocity, skeletal maturation (Bone age &
growth rate )
• GnRH agonist to prevent central precocious puberty.
• ILLNESS- ppt crises – increase hydrocort 2-3 folds (100mg),
decrease gradually
• Growth hormone & long acting GnRH agonist to maximize
height.
• S/e corticosteroid- Obesity & HTN
• SURGICAL M/m- Clitoroplasty, Separation of labial folds,
Vaginoplasty.
Postponed until child is older & can participate in decision
41. 5. ADULTS: goal is to lower & maintain androgens & adr precursors
(17 OHP)
• After epiphysial closure – Long acting glucocorticoid
• Dexa 0.25-0.75mg btwn 2AM to 10 AM
• Others- Prednisone, hydrocort
• s/e- osteoporosis, cushing syndrome
• Fludrocort 0.1-0.2mg/d
6. PREGNANCY: Hydrocort dose increased
Cesarean section
42. FETOPLACENTAL ORIGIN ANDROGEN EXCESS
1.Aromatase deficiency:
• 19 c androgen to aromatic 18 c estrogen.
• Chrm 15, AR
• Female fetal virilization , low maternal estrogen
and maternal hirsutism.
• Ambiguous genitalia, 1ry amenorrhoea with
hyperandrogenism.
43. 2.P450 oxidoreductase deficiency:-
• Chrm 7
• 46 XX (female virilization) & 46XY (incomplete male
virilization)
• Partial deficiencies in 21 hydroxylase, 17, 20 lyase & to less
extent 17 alpha hydroxylase ,aromatase.
• Cortisol levels usually Normal, Raised 17OHP, Low DHEA &
andrestenedione
• Female Virilization in utero by “backdoor androgen pathway”
44.
45. MATERNAL ORIGIN ANDROGEN EXCESS
Gestational hyperandrogenism
Hirsutism, temporal balding, clitoromegaly,deepning of voice in
pregnant women.
Early pregnancy exposure- labioscrotal fusion & clitoromegaly of
female fetus
> 12wks- clitoromegaly
1. DRUGS-
• Danazol for endometriosis
• Progestins for threatened/ recurrent abortions
Testosterone Diazoxide
Minoxidil Danocrine
Phenytoin sodium Streptomycin
Penicillamine
46. 2. EXCESS ANDROGEN PRODUCTION-
• M/c/c- Luteomas & Theca lutein cysts
• Pelvic USG – All theca lutein cyst & ½ Luteomas are bilateral
• Surgery rarely needed as regress after delivery.
a) PREGNANCY LUTEOMA- Hyperplastic masses of lutenized cells
6- 10 cm in size
1/3 rd – maternal hirsutism
no risk to female fetus if mother not virilized
regress after delivery
b) THECA- LUTEIN CYST - Associated with increased hCG
10-20% with GTD
10- 15 cm
30% hirsute or virilize
47.
48. OTHER DISORDERS
1. CLOACAL EXTROPHY- rectum, vg, urinary tract single orifice,
omphalocoele, imperforate anus
2. MRKH
3. MURCS- Mullerian renal cervico thoracic somatic dysplasia
51. Complete Gonadal Dysgenesis
(SWYER SYNDROME)
• Streak gonads with no AMH nor androgens
• Int gen & ext gen – female
• Cause- 10-15% Sry inactivation
• Features- Delayed puberty, 1ry amenorrhea, normal pubic
hair & normal int , ext gen
• Treatment- Gonadectomy soon after diagnosis
Female sex assignment
Estrogen for breast devp
Cyclic E & P for sexual maturation
Pregnancy by donor oocytes (IVF)
52. Partial Gonadal Dysgenesis
• Varieties of genetic mutations –
Single gene disorders (WT1, SRY, SF1, SOX9 etc)
Chrom Aberrations (Wnt4, Dax1, DMRT1)
• Mullerian struct absent or present
• Ext Gen female/ ambiguous/ male
• Other devp anomalies
53. Testicular Regression Syndrome
• Developmentally normal testes during but fetal life
regressed / lost later
• Unilateral/ bilateral
• Partial/ Complete absence of testicular tissue
• Normal male Ext Gen
• Cause- Might be catastrophic event (torsion)
• Features- Late in pregnancy- Int & Ext Gen virilize, anorchia,
small phallus, incomplete masculinization
55. 5 α Reductase Deficiency
• AR, Type 2 enzyme defect
• Testosterone DHT Blocked impaired virilization
• 46XY with severe perineal hypospadias (phallus size btwn penis & clitoris,
chordee tethering phallus into perineum, urethra on perineum, small vg)
• Ext Gen- Female
• Int Gen- Male
• Testes in inguinal canal/ labia majora/ scrotum & impaired spermatogenesis
• Virilize to varying degrees at puberty
• Breast like normal male (contrast to AIS)
• Less body hair, less temporal hairline recession, no acne (Less DHT)
• Females- Body hair reduced, delayed menarche
56. urogenital sinus with separate
urethral and vaginal openings,
and posterior labioscrotal fusion
clitoromegaly with marked
labioscrotal fusion and small
vaginal introitus
57. Diagnosis -
• Infants with ambiguous genitalia , Adolescents phenotype
• serum hormone profile (normal testosterone, increased TT/DHT ratio > 10
infants, >20 in children & adults)
• hCG stimulation test- measure testosterone & DHT before & after (3rd & 6th
day) administration of 1500 IU/m2 hCG
Management- Sex assigned according to sex of rearing & psychological sex .
• Female- Gonadectomy , Clitoroplasty, Vaginoplasty, Estrogen t/t at puberty or
after gonadectomy
• Male- Hypospadias & cryptoorchidism correction, Testosterone t/t
58. 3β-Hydroxysteroid Dehydrogenase Deficiency
• incomplete masculinization with salt-wasting impaired aldosterone and
cortisol synthesis
• a small phallus, hypospadias with labioscrotal fusion, a urogenital sinus, and a
blind-ending vaginal pouch. Testes are often scrotal, and wolffian ducts
develop normally
• diagnosis: increased levels of 3β-hydroxysteroids (pregnenolone, 17-
hydroxypregnenolone, and DHEA)
17α-Hydroxylase Deficiency
• conversion of pregnenolone and progesterone to 17-hydroxypregnenolone
and 17-hydroxyprogesterone
• impaired cortisol production ACTH hypersecretion increased DOC,
corticosterone, and 18-hydroxycorticosterone in the adrenals
• These mineralocorticoids salt and water retention, HTN, and hypokalemia
• FEMALE- 1ry amenorrhea, delayed puberty, hypergonado hypogonadism, HTN
hypokalemia
• MALE- Ext g- female, Int Gen- Male & Intraabd testes
• T/t- Glucocort, Estrogen therapy
59.
60. 17,20-Lyase Deficiency
• cortisol and ACTH secretion are normal aldosterone normal no HTN
• ambiguous rather than totally female genitalia at birth
• suspect this dx if absent müllerian derivatives and no defect in glucocorticoid or
mineralocorticoid synthesis.
17β-Hydroxy steroid Dehydrogenase Deficiency
• Most common hereditary defect in testosterone synthesis
• Type 3 convert Androstenedione androgen, testosterone
• Male- normal int gen & undescended testes, Ext gen- female (blind vagina)
At puberty Virilization phallic growth and male secondary sexual characteristics
• Diagnosis- Androstenedione increased to 10 to 15x normal
Testos/ Androstn <0.8- 0.9 after hcg stimulation
• T/T- Gonadectomy, Estrogen therapy (if reared as F)
61. P450 Oxidoreductase deficiency-
As described earlier
StAR protein deficiency- Chrm 8p
• Congenital Lipoid Adrenal Hyperplasia
• Rarest & severest form of CAH
• Def of all adr & gonadal steroid hormones, raised ACTH, Adr hyperplasia,
cholesterol ester accumulation
• Infants- Severe adrenal insufficiency
• Male- Ext g is female, a blind-ending vaginal pouch
intra-abdominal, inguinal, or labial testes
absence of mullerian structures & Wolffian ducts are present but rudimentary
• Female- Normal genitalia & puberty
• T/t- Gluco & mineralo
• Abdominal CT scan- large, lipid-laden adrenal glands
63. Complete Androgen insensitivity syndrome
• Testicular Feminization syndrome
• 1 in 20,000 to 1 in 60,000 males
• Chrm Xq12 (X linked recessive)
• Normal testes AMH suppress mullerian & descent of testes up to inguinal
canal
• Ext G- Female, Axillary & Pubic hair absent, Breast enhanced, Good height
• Presentation- Female with 1ry amenorrhea 2% of female with hernia
• Unequivocal female gender identity androgen resistance of brain tissue
• Serum Testos N/raised, LH increased, FSH normal, Estrogen raised, DHT decreased
• T/t- Hormone therapy, Vaginoplasty, Gonadectomy after puberty (16-18 yrs)
• Low (5-10%) risk of seminoma or gonadoblastoma before puberty
• Testis produces estradiol helps feminization
64.
65. Incomplete Androgen Insensitivity
• Reduced number of normally functioning androgen receptors
• Normal receptor number but decreased binding affinity
68. Infertile Male
• Mildly under masculinized & infertile
• Normal Ext & Int G, normal testes, some gynecomastia
• 10% men with azoospermia / severe oligospermia have Partial AIS
• Decreased androgen receptor binding to DHT in genital skin fibroblasts
Diagnosis of AIS- Most reliable method- sequence AR gene
69. 5α-reductase Complete Incomplete Reifenstein Infertile
Inheritence Autosomal
recessive
X-linked
recessive
X-linked
recessive
X-linked
recessive
X-linked
recessive
Spermatoge
nesis
Decreased Absent Absent Absent Decreased
Mullerian Absent Absent Absent Absent Absent
Wolffian Male Absent Underdevp Male Male
External Female Female Female
clitoromegaly
Male
hypospadias
Male
Breasts Male Female Female Gynecomastia M (Gynecomastia)
70. MANAGEMENT OF INCOMPLETE AIS
• Appropriate gender assignment- Size of phallus & feasibility of constructing male
urethra
• Hormone therapy- Estrogen therapy for female after puberty.
Female Children- consider growth percentile, velocity, bone age, target
height & predicted adult height.
Boys- with Reifenstein syndrome – High dose testosterone
Adult men- Might improve masculinization
• Psychological support- early disclosure
• Gonadectomy- Earlier to prevent virilization at puberty (F) & maximise
function(M)
• Reconstructive surgeries
• Gynecomastia in men – mastectomy (Risk of breast ca raised in Reifenstein)
71. LH Receptor Defects
• AR
• Inactivating mutation in LH/hCG receptor gene Leydig cell
hypoplasia decrease testosterone production
• Mullerian – Absent (Normal AMH)
• Wollfian – Impaired (Decreased Testos)
• Testes – Undescended (require IGF3 & Testos, both by Leydig)
• Phenotype – Completely N female to nearly N Male
• At puberty - Females present with 1ry amenorrhea, sexual infantalism,
Pubic hair & Breast Absent
• LH raised & testosterone decreased
72. Disorders of AMH & its Receptor
• Hernia uterine inguinale syndrome
• AR
• AMH receptor gene defect mullerian persists
• AMH gene 45%, AMHR2 receptor gene 39%, No mutation detected
15%
• Normal male Int & Ext Genitalia ,
• Cryptorchid testes &
• Inguinal hernia containing Mullerian structures during hernia repair
• M/M- Require orchidopexy
• Vas deferens are in close proximity to the uterus and proximal
vagina not to remove to preserve fertility
• Malignancy of retained müllerian structures has not been reported
75. TRUE HERMAPHRODITISM
• Gonads :
- ovary one side and testis on the other or
- bilateral ovotestis
• Karyotype :
46,XX most common(57%); XY(13%) and XX/XY(30%)
• Internal genitalia :
Both mullerian and wolffian derivates
• Phenotype is variable
•
76. XX XY
XX O X Y
XXX XO XXY YO
OVUM SPERMATOZOON
NON-DISJUNCTION
77. Turner’s Syndrome (45,XO)
1 in 2500 live births
60% are 45,XO and 40% are mosaics
No oocytes remain in the ovaries, which
become streaks
Ovum donation for those with bilateral streaks
33% - 60% have structural or positional
abnormalities of the kidney
horseshoe kidney = 10%,
duplication or renal agenesis= 20%
malrotation= 15%
multiple renal arteries = 90%
Four classic features:
female phenotype
short stature
lack of secondary sexual characteristics
a variety of somatic abnormalities:
Cubitus valgus
Wide spaced nipples
Broad chest (shield)
Webbed neck
Short stature
peripheral edema at birth, short 4th metacarpal,
hypoplastic nails, multiple pigmented nevi,
coarctation of the aorta, and renal anomalies
78. Characteristics
1. Short slender female less than 5 ft.
2. Secondary sexual ratio altered
3. Breast B0 or B1
4. Body hairs absent
5. Shield chest,webbing of neck,cubitus
valgus
6. CVS abnormalities (aortic
stenosis,coarctation of aorta)
7. Urinary abnormalities
8. Mental retardation
9. External genitalia poorly developed.
10. Uterus and tubes –hypoplastic
11. Internal gonads-agenetic or
dysgenetic
12. Primary ovarian failure
13. Colour blindness and multiple navi
on skin
14. Hashimoto’s thyroiditis,Addison’s
disease and vitiligo are common.
15. Anormality of lymphatic system
may sometimes cause gross swelling
of thelegs in the child or adult.
79. Seminiferous Tubule Dysgenesis (Klinefelter's
syndrome) Syndrome characterized by eunuchoidism, gynecomastia, azoospermia, increased
gonadotropin levels, and small, firm testes, 47,XXY karyotype
nondisjunction during meiosis
1 of 1000 liveborn males
associated with 48,XXYY; 49,XXXYY; 48,XXXY; 49,XXXXY; 46,XY/47XXY
Gynecomastia can be quite marked at pubertal development
8 X risk for breast carcinoma compared with normal males
Seminiferous tubules degenerate and are replaced with hyaline
After birth tubules are aplastic and functionless so sterility is the rule.
decreased androgens prevents normal secondary sexual development
poor muscle development, the fat distribution is more female than male.
Normal amounts of pubic and axillary hair, but facial hair is sparse.
Patients tend to be taller than average, due to disproportionately long legs
Predisposed to malignant neoplasms of extragonadal germ cell origin.
Androgen supplementation to improve libido & reduction mammoplasty
81. 46,XY Complete Gonadal Dysgenesis
Characterized by :
normal female genitalia
well-developed müllerian structures
bilateral streak gonads
nonmosaic karyotype
Ambiguity of genitalia is not an issue
Sexual infantilism is the primary clinical problem
present in their teens with delayed puberty
An abnormality of the Sry gene function, or loss of another gene
downstream from Sry that is necessary for SRY protein action
LH elevated clitoromegaly
30% risk of germ cell tumor development by age 30 years
gonadoblastoma is most common
embryonal carcinoma, endodermal sinus tumor, choriocarcinoma, and immature teratoma
have also been reported
Management removal of both streak gonads and proper cyclic hormone
replacement with estrogen and progesterone
82. Mixed gonadal dysgenesis (MGD)
Characterized by a unilateral testis, often intra-abdominal
Contralateral streak gonad
Persistent müllerian structures with varying inadequate masculinization
Most are 45,XO/46,XY, the most common form of Y chromosome mosaicism
Second most common cause of ambiguous genitalia after CAH
Dysgenetic or streak gonad is associated with ipsilateral mullerian derivatives (uterus,
fallopian tube)
Well-differentiated testis with functional Sertoli and Leydig cells will have ipsilateral
wolffian but no mullerian ducts
no germ cells so infertility is the rule
Increased risk of developing gonadoblastoma or dysgerminoma of 15% to 20%
Also increased risk for Wilm’s tumor .
Endocrine function of testis is normal post-pubertally
fetal testis dysfunction may account for ambiguous genitalia
90% to 95% of 45,X/46,XY mosaicism have normal-appearing male genitalia
83. Bilateral dysgenesis of testes( Swyer
Syndrome)
XY karyotype with mutation in SRY gene.
Fibrous bands in place of gonads.
Female internal and external genitalia
presents with primary amenorrhea and lack of
secondary development at puberty.
To prevent neoplasia removal of band areas is
advocated as diagnosis is made.
84. Anorchia
XY individual with infantile umambiguous
male external genitalia and male wolffian
ducts and lack mullerian ducts.
No detectable testes, early testes did occur
but was not sustained in sufficient amount or
duration to develop normal size phallus.
Also known as “disappearing testis
syndrome”.
85. Noonan syndrome
Inheritence autosomal dominant
Both affected male and females have normal
chromosome complements and normal gonadal
function.
The phenotypic appearance is that of a patient
with turner syndrome. The cardiac lesions are
different, pulmonic stenosis as opposed to aortic
coarctation.
These are fertile.
86. AMBIGUOUS GENITALIA AT
BIRTH
The external genital organs look
unusual, making it impossible to
identify the sex of the newborn
from its outward appearance.
Any one of the following :
A small, hypospadiac phallus
and unilaterally
undescended gonad.
An enlarged phallus with
bilaterally impalpable
gonads.
An enlarged phallus and a
vagina in the same infant.
87. MANAGEMENT OF NEWBORN WITH
AMBIGUOUS GENITALIA
GENERAL GIUDELINES
Medical and social emergency
Avoid immediate declaration of sex
Proper counselling of the parents
Team management; obstetrician,
neonatologist, pediatric endocrinolgist,
genetist and paediatric surgeon.
88. MANAGEMENT OF NEWBORN WITH
AMBIGUOUS GENITALIA
DIAGNOSIS
History : pregnancy; family
Detailed examination : abdomen; pelvis;
external genitalia; urethral and anal
openings.
Federman’s rule: a palpable gonad below the
inguinal ligament is testes until proven
otherwise
89. MANAGEMENT OF NEWBORN WITH
AMBIGUOUS GENITALIA
Investigations
• Rule out cong. Adrenal hyperplasia: Serum electrolytes; 17-
OHP level and urinary levels of 17-ketosteroids
• Karyotype ( buccal smear; blood)
• Pelvic US and sometimes MRI or Genitogram
• Skin biopsy; fibroblast culture to measure 5alpha-reductase
activity or dihydrotestosterone binding
• Laparoscopy
• Gonadal biopsy (laparotomy)
90. Sex assignment
1)Phallus length- Male gender assignment :
- stretched phallus > 2.5 cm
- erectile tissue
- lack of severe hypospadias
Female gender assignment :
- clitoris < 1cm
- cervix and uterus present.
2) Degree of labioscrotal fold fusion
In difficult cases; sex assignment should be
to the sex which can be surgically made to be
adequate for coitus
92. SURGICAL CONSIDERATIONS
Phallic / clitoral reduction if the assigned sex is female, before 3 years
of age
Removal of intra-abdominal gonads / streaks in newborns carrying Y
chromosome
Vaginal construction / repair is better performed around puberty
100. Transsexualism
Transsexualism occurs when a person strongly
believes that he or she belong to the opposite sex.
This is typically a lifelong feeling and results in
varied degrees of physical/external changes
These patients should be referred to the psychiatrist