Endocrine Flashcards
Fall in which hormone precedes menstruation?
Progesterone
= corpus luteum degrades, reduced production of progesterone > shedding of endometrium
Panretinal photocoagulation
- Target
- Complication
= focuses on peripheral retina
- Decrease in night vision: rods found mainly in periphery and responsible for night vision
- Decrease in peripheral vision
Pseudohypoparathyroidism
- What is it?
- Inheritance
- Blood results profile
Type I and II
- Lack of response to PTH due to mutation in receptor
- Autosomal dominant
- Raised PTH but LOW calcium
What endocrine abnormality is associated with pulmonary TB?
Hyponatraemia due to SIADH
What kind of receptor does insulin act on?
Tyrosine kinase
Firm non tender goitre with nil thyroid symptoms
- diagnosis
- association
Riedel’s thyroiditis = fibrous invasion of thryoid
Associated with retroperitoneal fibrosis
How does vitamin D raise serum calcium
Via increased gut absorption of calcium
First line management of primary hyperparathyroidism
Surgery
Klinefelter’s Syndrome
- Hormone results
Testosterone LOW
LH and FSH LOW or inappropriately normal
- they should be raised to try and boost the testosterone levels
Treatment of phaeochromocytoma
Non-selective alpha blocker
e.g. phenoxybenzamine
Phaeochromocytoma + medullary thyroid cancer
- Syndrome
- Genetic fault
MEN II
A. parathyroid adenomas
B. marfanoid habitus
RET oncogene
Drug class sitagliptin
- Mechanism
DPP-4 inhibitor
= increases GLP-1 levels by decreasing their breakdown
Mechanism of action of bisphosphonates
Inhibition of osteoclasts
Glucocorticoid VS mineralocorticoid effects
Glucocorticoid = anti-inflammatory
Mineralocorticoid = fluid retention (via secretion of aldosterone)
Which steroid has the least mineralocorticoid effects?
Dexamethasone - why so useful in brain tumours and desired anti-swelling effect
What cancer is associated with hashimoto’s thyroiditis?
MALT lymphoma
What is octreotide?
Mechanism of action
Produced from where?
Somatostatin analogue
Inhibits serotonin
D cells
How does carbimazole work?
Blocks thyroid peroxidase from binding to residues on thyroglobulin
Kallman Syndrome =
hypogonadotrophic hypogonandism
11 beta hydroxylase deficiency =
Congenital adrenal hyperplasia
Subacute thyroiditis =
De Quervain’s thyroiditis
Results in high dose dexamethasone suppression test
- +VE
- -VE
+VE = supressed cortisol, likely pituitary cause
-VE = cortisol not supressed, likely adrenal/ectopic cause
Causes of raised gastrin (4)
Gastrinoma
Zollinger-Ellison syndrome
Vagotomy
PPI
TSH
- controlled by
- actions (2)
Under control of TRH
Actions
1. Growth of thyroid gland
2. Synthesis + release of T3/T4
LH
- controlled by
- cell
- actions (2)
GnRH
Leydig cells
1. Male - increased testosterone production
2. Female - development of corpus luteum
FSH
- controlled by
- cell
- action
GnRH
Sertoli cell
Action = increase in seminiferous tubules
Prolactin
- controlled by
- increased (4)
Inhibited by dopamine
Increased = exercise, pregnancy, hypothyroidism, renal failure
Growth Hormone
- controlled by
Inhibited by somatostatin
What is the most common cause of Conn’s syndrome
Bilateral adrenal hyperplasia
Effect of hypocalcaemia on NMJ
Increased neuronal excitability - can result in tetany
What does axillary freckling feature in?
Neurofibromatosis
NOT a feature of tuberous sclerosis
Types of amiodarone-induced thyrotoxicosis
- management of each type
Type 1 = excess hormone synthesis, see goitre
Give carbimazole
Type 2 = destructive thyroiditis
Give steroids
Type 1 amiodarone thyrotoxicosis management
Give carbimazole
Type 2 amiodarone thyrotoxicosis management
Give steroids
Treatment of Paget’s Disease
Bisphosphonate
Mechanism of action of Bisphosphonate
Inhibits bone resorption by INTERFERING with osteoclasts
Gold standard diagnosis for insulinoma
Supervised prolonged fasting
Malignancy associated with acromegaly
- why?
Colorectal cancer
Increased secretion of growth hormone
Investigation of Zollinger Ellison Syndrome
Secretin stimulation test
= paradoxical rise in gastrin secretion
Gastrin is usually inhibited by secretin
What can cause a worsening of thyroid eye disease?
Radioiodine
Most common cause of congenital adrenal hyperplasia
21 hydroxylase deficiency
Options for management of Grave’s Disease (2)
Down titration of carbimazole
Block and replace - carbimazole, start levothyroxine when euthyroid
Down titration has a better side effect profile
Mechanism of metabolic alkalosis in cirrhosis
Reduced steroid hormone production
Depleted intravascular volume
= increased secretion of aldosterone
= metabolic alkalosis
How do the metaglitinides work?
Same mechanism as sulphonylureas
