Embryology and CAH Flashcards
1
Q
Origin of congenital sinus
A
Endodermal
2
Q
Parts of urogenital system that are endodermal in origin are
A
Lower 1/3rd of Vagina and Vaginal epithelium
3
Q
Intermediate mesoderm gives rise to
A
Genital ridge and ducts.
4
Q
Genital ridge derivatives are
A
Gonads and Renal system.
5
Q
Gonads develop at
A
5 wks
6
Q
Sex of baby is decided by
A
SRY region or Testis determining factor.
7
Q
SRY gene present means
A
Male
8
Q
Medulla of gonads gives rise to
A
Testis
9
Q
Cortex of gonads gives rise to
A
Ovary
10
Q
Testis @ which week
A
7th week
11
Q
Ovary @ which week
A
8th week
12
Q
Genes associated with testis
A
SOX - 9
13
Q
Genes associated with Ovary
A
RSPO - 4 and WnT - 4
14
Q
1st feature to distinguish between Testis and ovary
A
Formation of testicular cords
15
Q
Testis and ovary are indistinguishable till
A
10-11 wks
16
Q
Blood - Testis barrier is formed by
A
Sertoli cells
17
Q
For complete formation of ovaries _____ is required
A
Two X chromosome.
18
Q
Turner’s syndrome
A
45XO - Gonads are ovary- No Y chromosome.
Streak ovaries - Coz of only one X chromosome.
19
Q
Mesonephric Duct
A
Wolffian
20
Q
Paramesonephric Duct
A
Mullerian
21
Q
Ducts appear by
A
6 weeks
22
Q
____ ducts disappear in Females
A
Wolffian
23
Q
_____ ducts disappear in Males
A
Mullerian
24
Q
Mullerian and wolffian ducts disappear by
A
9 weeks.
25
Sertoli cells secrete ____ at 7 th week.
Anti mullerian factor or Testis inhibiting Hormone.
26
Remnant of Mullerian duct in males.
Prostatic Utricle
| Appendix of testis - Hydatid of Morgagni.
27
Leydig cells secrete _______
Testosterone.
28
Testosterone production begins @ ___
8 th week
29
Testosterone production is maximum @_____
15 weeks
30
_____ promotes wolffian duct production in males
Testosterone produced by leydig cells
31
Male internal genital organs formed from Wolffian ducts are
S - Seminal vesicle
E - Ejaculatory ducts
E - Epididymis
D - vas Deferens
32
_____ helps in formation of Male external genital organs from Lateral mesoderm
Testosterone from Leydig cells.
33
Appendix of testis
Remnant of mullerian duct
34
Appendix of Epididymis
From Wolffian duct or mesonephric duct
35
Efferent ductules of testis is derived from
Mesonephros.
36
Remnants of Pronephros
Kubelt tubercle or hydatid of morgagni
37
Remnant of caudal end Mesonephros
Paranephros
38
Remnant of Cranial end of Mesonephros
Epo-Nephros
39
Remnant of Mullerian duct in Females
Gartner's duct.
40
After mesonephric duct gives rise to Ureteric bud it is called as
wolffian duct
41
Hydatid of morgagni in males
Remnant of Mullerian duct
42
Hydatid of Morgagni in females
Remnant of Pronephros or Kubelt tubercle
43
Anti mullerian Hormone deficiency
AMH is produced only in males to suppress MD
So in its absence - MD does not regress
MD form Female internal genital organs - FT, Uterus, Cervix and upper 2/3rd of vagina.
Wolffian duct - grows male internal and external genital organs .
Leads to Uterus herniation syndrome or Persistent Mullerian duct syndrome.
44
Persistent mullerian duct syndrome caused by
Deficiency of Anti mullerian hormone leading to non regression on Mullerian duct in male.
45
Not a cause of Ambiguous genitalia in males
AMH deficiency or persistent mullerian duct syndrome
46
Uterine herniation syndrome
```
Less space coz of both Male and Female internal genital organs being present.
Cryptorchidism.
Vas Deferens obstruction.
Infertility
Herniation of uterus .
```
47
Developments of ducts in females.
Since gonads are ovaries - no sertoli or leydig cells.
Since no Sertoli cells - no AMH or TIF so MD develops female Internal genital organs.
Since no leydig cells - no Testosterone - so Wolffian ducts regress and no Male Internal and external genitalia.
48
Remnants of Wolffian ducts in Females
Pronephros - Kubelt tubercle or hydatid of morgagni
Mesonephros - Cranial - Eponephros
Caudal - Paranephros.
Mesonephric duct - Gartner's duct.
49
Lower 1/3 rd of vagina is derived from
Genital sinus / Sino-vaginal bulb
50
Sinovaginal bulb gives rise to
Lower 1/3rd of vagina
51
Vaginal epithelium is derived from
Endoderm - Genital sinus
52
Development of external genitalia
They develop from lateral plate mesoderm - Dorsal somatic part.
Depends on Testosterone levels.
If present - Male ext genitalia.
If absent - Female ext genitalia.
53
Genital tubercle
Penis / Clitoris
54
Genital Fold
Penile urethra / Labia minora
55
Genital Swelling
Scrotum / Labia majora
56
Sex of baby can be determined via USG by
14 weeks
57
Homologous organs
Same embryological origin
58
Homologous organ of Prostate
Skene or paraurethral glands
59
Homologous organ of Cowper or bulbourethral glands
Bartholin gland
60
Homologous organ of littre gland
Glands in labia majora and minora.
61
MCC of Ambiguous genitalia in male
Androgen Insensitivity syndrome or testicular feminizing syndrome
62
MCC of Ambiguous genitalia in females
CAH
63
MC structures affected in Ambiguous genitalia
Clitoromegaly.
Fusion of Labioscrotal folds.
Phallus (Penile Urethra)
64
True Hermaphroditism.
Both testis and ovary are present.
| 46XX is the most common stereotype.
65
Pseudohermaphroditism
Gonads of one sex and external genitalia of other.
66
Male Pseudohermaphroditism
Gonads - Testes - External genitalia of female
| MCC- Androgen insensitivity syndrome
67
Female Pseudohermaphroditism
Gonads- Ovary - External genitalia - Male
| MCC- CAH
68
DHEA - Steroid pathway
Pregnenolone to 17 hydroxypregnenolone to DHEA
| Enzymes- 17 hydroxylase and 17,20 lyase
69
Pregnenolone to 17 hydroxypregnenolone.
| Enzyme .?
17 hydroxylase.
70
Pregnenolone to aldosterone pathway
Pregnenolone to progesterone to deoxycortisone to cortisone to Aldosterone
Enzymes -3 beta HSD, 21 hydroxylase, 11 beta hydroxylase, 18 hydroxylase.
71
Pregnenolone to Progesterone. Enzyme
3 beta HSD
72
Progesterone to Deoxycortisone. Enzyme.
21 hydroxylase.
73
Deoxycortisone to Cortisone.
| Enzyme
11 beta Hydroxylase.
74
Cortisone to Aldosterone. Enzyme.
18 Hydroxylase.
75
17- Hydroxypregnenolone to Cortisol pathway.
17- Hydroxypregnenolone to 17 OH Progesterone to Deoxycortisol to cortisol.
Enzymes- 3 beta HSD, 21 hydroxylase, 11 Beta Hydroxylase, 18 hydroxylase.
76
enzyme 3 beta HSD. which reaction's.?
Pregnenolone to progesterone and 17 hydroxypregnenolone to 17 OH Progesterone.
77
21 Hydroxylase Enzyme. Which reaction's.?
Progesterone to Deoxycortisone.
| 17 OH Progesterone to Deoxycortisol.
78
11 Beta Hydroxylase Enzyme. Which reaction.?
Deoxycortisone to Cortisone.
| Deoxycortisol to Cortisol.
79
18 Hydroxylase Enzyme. Which reaction.?
Cortisone to Aldosterone.
80
Progesterone to Testosterone Pathway.
Progesterone to 17- OH Progesterone to Androsterone to Testosterone.
Enzymes- 17 hydroxylase and 17,20 lyase.
81
MC enzyme deficiency in CAH
21 hydroxylase
| Progesterone to dexycortisone.
82
2nd MC Enzyme deficiency in CAH
11 Beta Hydroxylase.
| Deoxycortisone to Cortisone.
83
Least common Enzyme deficiency in CAH
3 beta HSD- Hydroxysteroid dehydrogenase.
84
21 Hydroxylase is needed for production of ___ by Adrenals.
Cortico and mineralosteroids.
85
21 Hydroxylase is not needed for production of ____ by Adrenals
Progesterone and Androgens.
86
Pathogenesis of CAH - 21 hydroxylase.
21 hydroxylase is needed for production of Corticosteroids and mineralocorticoids by Adrenals.
Which provide negative feedback on ACTH.
Since no Cortico and mineralocorticoids - no negative feedback - inc ACTH - inc Progesterone and androgens.
87
Inc androgens causes _____ in CAH in females.
Ambiguous genitalia - Clitoromegaly, Labioscrotal fusion and phallus formation.
Precocious puberty - heterosexual.
Virilisation.
Short stature due to early epiphyseal fusion.
88
CAH in Males.
no ambiguous genitalia but other characteristics are present which are just normal male characteristics.
89
Heterosexual Precocious puberty in female causes
Virilisation, Hirsutism, Inc muscle mass, Deepening of voice and clitoromegaly.
90
Increased androgens effect + salt water wasting + Hyponatremia and hypokalemia + Hypotension=
CAH due to 21 hydroxylase deficiency
91
Increased Androgen effects + hypertension =
CAH due to 11 beta hydroxylase deficiency.
92
CAH with Hypertension.
11 beta Hydroxylase deficiency.
inc androgens- Ambiguous genitalia
inc deoxycortisone - hypertension.
93
Screening test for CAH
17 OH Progesterone.
if < 300 = not CAH
300 - 800 = do diagnostic test
> 800 = CAH
94
Diagnostic test for CAH
ACTH stimulation test.
Stimulate ACTH and check 17 OH Progesterone levels after 1/2 hr
if >1500 ng/dl = CAH
95
Mx of CAH
For Salt water wasting - Steroid of choice = Fludrocortisone.
Surgical removal of Phallus @ 4-5 yrs of age
For Corticosteroid deficiency = steroid of choice is age dependant
in Childhood - hydrocortisone - to prevent epiphyseal closure
@ puberty - Dexamethasone or prednisone
In pregnancy - Hydrocortisone - can not cross placental barrier.
96
Steroid of choice in CAH in childhood
Hydrocortisone - to prevent early epiphyseal closure
97
Steroid of choice @ puberty in CAH
Dexamethasone or Prednisone
98
Pregnancy in CAH females how to Mx.?
Steroid of choice is Hydrocortisone - does not cross placental barrier
@ 10 weeks - FISH - fluorescence In-Situ Hybridisation - If male or unaffected female - continue Hydrocortisone.
If affected female fetus - Give Dexamethasone to cross placenta.
99
Late onset CAH
@ puberty - inc androgens and progesterone.
normal genitalia but hirsutism, virilisation are present.
Dx is same as normal CAH
100
Pubertal woman with hirsutism - DDx
PCOS or late onset CAH
101
Virilisation Characteristics.
```
Female with secondary sexual characters resembling male.
Hirsutism,
inc muscle mass,
Deep voice,
Breast atrophy.
```
102
Gartner's cyst
```
Tender, shiny
No rugosities,
not reducible,
cough impulse is absent
Well defined margins
```
103
Cystocele
```
Not shiny and tender
Rugosities are present
Reducible
No clear margins
Cough impulse is absent
```
104
MC cyst in vagina
inclusion cyst
105
MC cyst in Ovary
Follicular cyst
