Endocrine Flashcards
(318 cards)
Androgen insensitivity syndrome, why do females often still develop breasts? Uterus / cervix? What is recommended?
Partial or complete lack of response to androgens. Have testis which produce Mullerian inhibing substance - inhibits grown of uterus and cervix -> BLIND ENDED VAGINA.
Fetus may not develop male external genitalia or secondary sexual characteristics at puberty.
Breasts often develop due to the peripheral conversion of circulating androgens to oestrogens
Reccomended orchiectomy due to risk of testis Ca
What is ashermans syndrome ?
Intrauterine adhesions from previous infection / scarring
[Think that dam surgeon Ash who made loads of scarring -> ASH-err-man
How to differentiate between androgen insensitivity syndrome and Mullerian agenesis?
Testosterone levels - RAISED in AIS [normal male levels]
Karyotype - XY in AIS
Who commonly gets secondary amenorrhoea
Endurance athletes
Breakdown some causes of amenorrhoea in women
Physiological - Constitutional delay, exercise/stress
GU malformations - imperforate hymen, transverse septum, absent vagina/uterus
Endocrine - HYPER/HYPOthyroid, PITUITARY (Hyperprolactinaemia, cranial irradiation, Sheehans, hypopituitarism Eg after TBI), Cushing, PCOS.
Genetic - Turners
Iatrogenic - chemo/radio
What is Sheehan’s syndrome?
Pituitary infarction after major obstetric haemorrhage
Seondary Amenorrhea + evidence of androgen excess eg hirsutism/acne. Differentials
PCOS
Cushing’s
Late-onset congenital adrenal hyperplasia
androgen-secreting tumours [RARE]
What might red/thin vaginal mucosa mean
Decreased oestrogen levels
Secondary Amenorrhea with high levels of FSH/LH? What would testosterone and prolactin levels be?
Indicates ovarian failure
NORMAL prolactin / tesoterone
When to refer girls with primary Amenorrhea
No secondary sexual characteristic - Age 13
With secondary characteristics - Age 15
Worries about anything else…
MEN 1 features? Genetic? Most common presenting factor
Pancreatic neuroendocrine tumours
Primary hyperparathyroidism
Pituitary adenomas
Dominant - chromosome 11
Usually present with HyperCalcium [due to hyperparathyroidism]
Familial hypocalciuric hypercalcaemia syndrome.
Inheritance? Abnormalities in blood?
Dominant
Raised serum Ca, raised PTH
[Obvs LOW ca urine]
MEN2a gene? features? differneces to MEN
RET gene - chromosome 10
Primary hyperparathyroidism - Usually due to an adenoma [MEN1 is usually generalised hyperplasia]
Often have pheochromocytoma +/- thyroid Ca
[DO NOT get pituitary adenomas or pancreatic neuroendocrine like in MEN1]
What is pseudohypoparathyroidism
caused by resistance to PTH
->Low PO4 and Ca levels [+raised PTH]
Important management in MEN2
Prophylactic thyroidectomy
GENETIC COUNCILING
Difference between MEN2 A and B
B - gets a marfanoid appearance and mucosal neuromas
Investigations for diagnosis of phaeo? Specific scan type?
24-hr urinary catecholamines
MRI
MIGB scan (metaiodobenzylguanidine)
Investigation for medullary thyroid Ca
Elevated calcitonin
US and fine needle aspiration
Ix for likely acromegaly? Why is it good
IGF-1 (then confirmed by glucose tolerance test + pituitary MRI, visual fields, cardiac assessment…)
Has a long half-life, and can be measured at any time of day
-> Can use for assessment of recurrence
A less common cause of acromegaly (not pituitary adenoma secreting GH)?
Carcinoid tumour elsewhere
What causes pseudo acromegaly? Drug?
Insulin resistance - associated with hyperinsulinaemia / minoxidil (antihypertensive and male pattern balding)
Non surgical options for acromegaly
Radiotherapy - may end up with panhypopituitarism
Drugs
Dopamine agonists: Bromocriptine and -goline / -golides
Somatostatin analogues: ocretide
Micro vs Macro prolactinoma
Smaller or bigger than 1cm …..
Management of macroprolactinomas
Usually a dopamine agonist (most common is CARBEGOLINE or bromocriptine)