Flashcards in Gynaecology Deck (91)
Loading flashcards...
1
Name types of intersex states
CAH, AIS, 5 alpha Reductase
2
Which intersex state may present later in life?
AIS - presents with amenorhoea
3
What is CAH?
Autosomal recessive.
Usually 21 hydroxylase deficiency
Reduction in cortisol and aldosterone
ACTH increases bu shunting into androgen synthesis pathway
4
What are the symptoms of CAH?
Salt wasting
Addisonian crisis in infants
Precocious puberty in males
Virilisation of genitalia in female - ambigous
5
What are the investigations of CAH?
imaging - pelvic/renal/bladder
6
What is the management of CAH?
gender reassignment and replacement of cortisol and aldosterone
7
What is AIS?
High resistance to testosterone causing genetically male children to have a female phenotype
8
What are the symptoms of AIS?
Complete AIS → appear female at birth. Usually present with amenorrhoea, and will have a lack of body hair. The patient will have undescended testes and an absent uterus. Breast development may occur as a result of testosterone conversion to oestradiol.
Partial AIS → present with a varying degree of genital development. This can range from cliteromegaly to ambiguous genitalia
9
How is AIS diagnosed?
Buccal smear or chromosome analysis to reveal 46XY genotype
10
What is the management of AIS?
Counselling - raise child as female
Bilateral orchidectomy (increased risk of testicular cancer due to undescended testes)
Oestrogen therapy
11
What is 5 alpha reductase?
Autosomal recessive condition. Results in the inability of males to convert testosterone to dihydrotestosterone (DHT). (More potent, responsible for external genitalia differentiation)
12
Define sex determination
Sexual determination is a genetically controlled process dependent of the Y chromosome, i.e. it is the genetic determination of male or female. The key gene is the SRY (sex determining region Y), which determines whether a testis or ovary will form. The formation of a testis then regulates sexual differentiation.
13
Describe the process of sexual differentiation
Male - SRY - Sertoli cells develop - produce AMH mullerian duct degenerate.
Leydig cells - testosterone - wollfian duct - epididymis, vas deferens, seminal vesicle, ejaculatory duct .
DHT - external structures
Female - no SRY. Ovary develops. No sertoli cells so no MIS causing mullein duct development and Fallopian tubes, uterus, upper vagina.
no leydig cells - regression of wollffian ducts.
14
What is adrenarche and menarche?
Adrenarche - secretion of adrenal androgens leading to growth of hair, height.
Menarche - onset of menstruation.
15
Define delayed and precocious puberty
Precocious : The onset of secondary sexual characteristics before age of 8 in girls or 9 in boys
Delayed: Defined as the lack of any pubertal signs by the age of 13 years in girls and 14 years in boys.
16
What are causes of delayed puberty?
1Constitutional delay: idiopathic/ within families. Temporary delay due to severe illness in childhood, e.g. mumps.
2. Organic causes:
Hypothalamic [Hypogonadotrophic hypogonadism – low levels of LH/FSH and low levels of sex steroids]:
Congenital GnRh deficiency (e.g. Kallmann’s syndrome – where there is failure in migration of GnRH neurons) or acquired (trauma, surgery)
Gonadal [Hypergonadotrophic hypogonadism– high levels of LH/FSH and low levels of sex steroids]:
Congenital disorders, chromosomal disorders (e.g. Klinefelters) or acquired (e.g. testicular/ovarian torsion, radiation, surgery, infection)
17
What are causes of precocious puberty?
Classification:
1. Gonadotrophin dependent ('central', 'true') → consonance maintained
• Caused by excess GnRH secretion: either idiopathic (common in females) or secondary (trauma, radiotherapy, intracranial tumour or CNS damage)
• FSH & LH raised
2. Gonadotrophin independent ('pseudo', 'false') → loss of consonance
• Due to excess sex hormones
• FSH & LH low due to negative feedback
• Caused by:
o Ovarian: tumours
o Testicular: tumours, activating LH mutations on Leydig cells which release testosterone
o Adrenal: CAH in males
o Primary hypothyroidism: high levels of TSH acts on LH/FSH receptors causing a release of sex steroids
o McCune-Albright syndrome: Sx - precocious puberty, café au lait spots, fibrous dysplasia of the bones & short stature
o Exposure to exogenous steroids
18
Describe the events of puberty and when they occur
Thelarche
Menarche
puberache
19
What are the stages of the menstrual cycle?
Follicular phase → growth of follicles up to ovulation, dominated by oestrogen (variable length)
Luteal phase → formation of corpus luteum, dominated by progesterone production (always lasts 14d)
20
Outline the hormonal changes in the menstrual cycle?
1. Follicular phase:
Early in the follicular phase steroids low due to the regression of CL
FHS released from -ve feedback leading to the intercycle rise in FSH → follicle selection
• Dominant follicle is selected and produces oestrogen which gives –ve feedback causing FSH levels to fall
2. Mid-cycle:
• Dominant follicle continues producing oestrogen till levels exceed 300pmol where negative feedback switches to positive
• This causes an LH surge (and FSH peak)
• LH induces ovulation
3. Luteal:
• Corpus luteum produces progesterone and negative feedback is re-instated
• Withdrawal of progesterone leads to menses
21
How does 5 alpha reductase present?
Internal male structure are formed, external are not
May appear female or have ambiguous genitalia
Can undergo virilisation at puberty (high levels of circulating testosterone)
22
What are the causes of oligo/amenorrhoea?
Primary: structural or genetic
Secondary
Premature menopause, PCOS, hyperprolactinaemia
Physiological: pregnancy, lactating, pre or post.
Hypothalamic
Primary - congenital reduced GNRH. Secondary - stress, low fat/body weight, exercise
Pituitary
Hyperprolactinaemia, Sheehans
Ovarian
Acquired: PCOS or premature menopause
Congenital: turners
Endocrine; thyroid
23
How does 5 alpha reductase present?
Internal male structure are formed, external are not
May appear female or have ambiguous genitalia
Can undergo virilisation at puberty (high levels of circulating testosterone)
24
What are the first sign of puberty in girls?
First sign is breast development at around 11.5 years of age (range = 9-13 years)
Height spurt reaches its maximum early in puberty (at 12) before menarche
Menarche at 13 (11-15)
There is an increase of only about 4% of height following menarche
25
What are the investigations and management for precocious puberty?
Investigations:
Auxology: accurate measurements of height, body proportions + weight
Tanner stage + Ferriman and Gallwey scoring system for hirsutism
•Bone age estimation, LH, FSH, Sex steroids, US scan of pelvis, MRI of hypothalamic areas
•Measuring adrenal steroids: increased in tumours + in CAH, the precursors of androgens
Treatment: dampens down the effects of the sex steroids
Anti-androgens
5-alpha reductase inhibitors
Aromatase inhibitor – inhibits conversion of testosterone to oestrogen
Long acting GnRH analogues – dampens down the pituitary so there is no release of LH/FSH
26
What investigations and management would be needed for delayed puberty?
Same Ix as precocious. + Check anosmia for kallmans.
Mx
Testosterone/Oestrogen
Oxandralone (synthetic steroid)
Kallman’s can be treated using pulsatile GnRH as the gonads are still functioning
27
What is the Tanner staging system?
5 stages of development for breasts, pubic/axillary hair and male genitalia
28
Define menopause
Menopause is the permanent cessation of menstruation due to loss of ovarian follicular function. Average age 51.
12 months after the last period in women > 50 years
24 months after the last period in women < 50 years
29
When is menopause classified as premature?
<40
30
