L13 - Abnormalities of Gonads Flashcards
1. Congenital adrenal hyperplasia (CAH) 2. Disorders of sex development 3. Describe anomalies of female genital tract, common congenital uterine anomalies and link their formation to their embryological development.
Hermaphroditism?
Organism, complete or partial reproductive organs that produce gametes normally associated with both male and female sexes.
Describe briefly the pathophysiology of puberty?
- Onset due to increase pulsatile release GnRH from hypothalamus.
- Initially occurs at night
- As puberty progresses it occurs during day and night
- Pulsatile GnRH causes gonadotropic cells of AP to release LH and FSH
- Lead to oestrogen production
- causes physical changes of puberty
What do the Mullerian ducts differentiate into? (4)
Differentiate to form:
- Fallopian tubes
- Uterus
- Uterine cervix
- Superior aspect of Vagina
When do the Mullerian ducts develop?
6th week of embryonic development.
When does the urogenital sinus form?
By 7th week
If Mullerian anomaly is identified why is it important to assess renal tract?
- Mullerian duct develops in close proximity to kidneys
Hymen
Thin membrane that covers vaginal opening.
Patients with imperforate hymen may present with…
Ultrasound may show…
- increased cyclical abdominal pain in absence of menstruation
- palpable abdominal mass
- USS —> large haematocolpos
Haematocolpos is an….
Accumulation of blood in vagina
Treatment for patient with imperforate hymen?
Incision and resection of hymen
Transverse vaginal septa may result from…
Failure of canalisation of vaginal plate where UG sinus meets the Mullerian duct.
Treatment for a transverse vaginal septa?
Surgical resection of septum can be resected vaginally, laparoscopically or via an abdomino-perineal approach
Laparoscopy is…
- Keyhole surgery.
- Surgeon can access the inside of the abdomen and pelvis without having to make large incisions in the skin.
Longitudinal vaginal septum arises due to…
types..
- failure of canalisation of vaginal plate
- can be partial or complete
Treatment for longitudinal vaginal septum
Resection vaginally.
Resection is….
Process of cutting tissue or part of organ.
Describe what symptoms a patient with an abnormal uterine shape may present with?
Usually asymptomatic
however. .. patient may have:
- menorrhagia
- primary infertility
- recurrent pregnancy loss
Examples of abnormalities of uterine shape
loads
Unicornuate uterus Bicornuate Double uterus Septate uterus Vertical septate uterus Horizontal septate uterus
Unicornuate uterus
- Only one functioning fallopian tube.
- Half size of typical uterus.
- Common type of congenital uterine abnormality.
Define disorders of sex development?
DSD
- group of conditions where development of chromosomal, gonadal or anatomical sex is atypical.
Atypical
Not representative of a group
When do primordial gonads appear?
6th week of development
What occurs during sixth week of development? (3)
- Primordial gonads appear
- Gonadal ridge can be testes or ovaries. If SRY present then testes.
- Mullerian and Wolfian ducts also develop.
Which gene in XY embryo stimulates development?
- SRY gene in embryo stimulates testicular development.
- Sex Determining region on Y chromosome.
Describe how the Wolfian structures develop?
What are the Wolfian structures?
Testes produces testosterone.
This causes the development of Wolfian structures.
- vas deferens
- seminal vesicles
- epididymus
How does the virulisation of external genitalia occur?
- Peripheral conversion of testosterone to dihydrotestosterone (DHT)
- via the enzyme 5-alpha reductase.
At what week during pregnancy is a fetus recognisably male?
12 weeks.
When does the masculisation of genitalia occur?
14 weeks.
Where is antimullerian hormone produced and whats its role?
Testes – AMH
Causes regression of Mullerain ducts.
What occurs in the XX gonad in order to form a girl?
- Ovarian development promoted
- Testicular development inhibited
RECAP: Menstruation
DAY 1 - 4
Day 1 to 4
- Menstruation
- endometrium shed
- myometrial contraction
RECAP: Menstruation
DAY 5 - 13
Day 5 to 13
- Hypothalamus, GnRN pulses
- LH and FSH release
- induce follicular growth
- secrete inhibin and oestrogen.
This supresses FSH.
- Oestrogen increase
- LH surge , ovulation
- Oestrogen has role in endometrium reformation
RECAP: Menstruation (3)
DAY 14 - 28
- Follicle transforms into corpus luteum
- Follicle produces oestradiol and progesterone - Corpus luteum degenerates
- decreased progesterone
- decreased oestrogen - Endometrium breaks down
Describe the effect of progesterone on the endometrium?
- Stromal cells enlarge
- glands swell
- blood supply increases
Menorrhagia
Heavy menstrual bleeding
>80mls
How is congenital adrenal hyperplasia inherited?
Describe effects on boys and girls?
- autosomal recessive
- Effects boys and girls
- but only girls will have abnormal genitialia
Congenital adrenal hyperplasia occurs due to ?
- Defective cortisol production
- as a result of 21-hydroxylase deficiency.
ACTH causes…
Increased androgen production
What is the treatment for ACTH?
Cortisol and mineral corticoid replacement.
What is androgen insensitivity syndrome in males? AIS
- Male has cell receptor insensitivity to androgen, which peripherally converted to oestrogen.
- Individual appears to be female but has no uterus.
Describe role of sertoli cells during development
Promotes involution of mullerian structures
—> uterus, fallopian tubes will disappear.
What is a hydrocoele?
Why might it occur?
Briefly state an examination method to confirm its presence?
- Fluid in tunica vaginalis.
- if there is a patent processus vaginalis, intraperitoneal fluid
- If you shine a torch at it, it will light up
What is an inguinal hernia?
- Wide opening patent processes vaginalis
- allows herniation of abdominal contents along canal into scrotum.
Describe formation of male external genitalia
- Genital tubercle —> elongates
- Urogenital sinus —> extends along phallus
- Urogenital folds —> fuse to form penile urethra
- Labioscrotal swellings —>fuse to form scrotum
Whats a urethral meatus?
Urethra hasn’t made it to the tip of penis
Describe what may cause XY under virulisation? (3)
- Lack of tesosterone
- testiular failure, leydig cell hypoplasia - Failure to convert to DHT
- 5 alpha-reductase - Failure to respond to androgen
- androgen receptor defect
Describe an undescended testis?
classifications of undescended testis?
- Not in scrotum.
- intraabdominal, inguinal, extra inguinal and ectopic - Classified as either:
- palpable or impalpable
How long may it take a hydrocoele to resolve?
Normally resolves by 2 years.
Recap: Genital tubercle will….
Elongate
Recap: Urogenital sinus will…
Extends along phallus
Recap: Urogenital folds will…
Fuse to form penile urethra
Recap: Laboiscrotal swellings will…
Fuse to form scrotum
How may congenital adrenal hyperplasia lead to salt wasting?
- Defect in 21-hydroxylase may affect production of aldostersone.
- Aldosterone = salt salvaging hormone.
What may be some symptoms of CAH?
- Salt wasting
- Rapid growth, precocious puberty, short stature.
- Scanty, absent menstruation
- Prostatic enlargement, cancer
What are some treatment options available to a patient with CAH?
- Lifelong steroid replacement
- close monitoring, extra steroid crisis - Feminising genital reconstruction
- timing and extent controversial - Life long psychological support / counselling.
Upper part of vagina is formed from…
Mullerian tubes
What may be some problems a patient with a longitudinal vaginal septum may encounter?
Dyspareunia - Difficult sexual intercourse
Difficulty with tampons
Hard labour
What is a uterine horn?
Point where the uterus and the fallopian tubes meet.
What are the two points of attachment for the round ligament of the uterus?
Mons Pubis
Uterine horn
What is cervical agenesis?
typically presents…
- Congenital disorder, absent cervix.
- Typically presents in early adolescence, amenorrhea and cyclic pelvic pain caused by obstruction of menstrual flow from the uterus.
Treatment for cervical agenesis?
absence of cervix
- Combined oral contraceptive to suppress menstruation and thereby relieve pain.
- Hysterectomy relieves symptoms caused by hematocolpos.
What is Mayer-Rokitansky-Kuster-Hauser syndrome?
Failure of Mullerian duct to develop (fuse) : missing uterus
Why might the vagina still be present in MRKH?
Mayer-Rokitansky-Kuster-Hauser syndrome
- Vagina develops from urogenital sinus along with bladder and urethra not from Mullerian duct.
- Ovaries also do not develop from Mullerian duct hence women might have normal secondary sexual characteristics.
