Endocrinology Flashcards
What is acromegaly?
A condition caused by excessive growth hormone resulting in a coarse facial appearance, larger tongue and excessive sweating and oily skin.
What are the causes of acromegaly?
- Pituitary adenoma (>95% of cases)
- Ectopic GHRH or GH production by tumours e.g. pancreatic (rare)
What are the features of acromegaly?
- Coarse facial appearance, spade-like hands, increase in shoe size
- Large tongue, prognathism, interdental spaces
- Excessive sweating and oily skin: caused by sweat gland hypertrophy
- Features of pituitary tumour: hypopituitarism, headaches, bitemporal hemianopia
- Raised prolactin in 1/3 of cases → galactorrhoea
In what condition do 6% of patients have MEN-1?
Acromegaly
What is the first-line treatment for acromegaly?
Trans-sphenoidal surgery
If surgery to remove a pituitary tumour causing acromegaly cannot be done (unresectable) then what is the treatment?
1st line: somatostatin analogue (adjuncts dopamine agonist and debulking surgery)
2nd line: growth hormone-receptor antagonist (GHRA)
3rd line: radiotherapy
What is the method of action of a somatostatin analogue?
It directly inhibits the release of growth hormone
In what proportion of patients with acromegaly are somatostatin analogues effective?
50-70%
In what proportion of patients with acromegaly are GH receptor antagonists effective?
90%
What is an example of a somatostatin analogue?
Octreotide
What is an example of a GH receptor antagonist?
Pegvisomant
What is an example of a dopamine agonist?
Bromocriptine
What is Graves’ disease?
An autoimmune condition associated with hyperthyroidism
What are the key diagnostic factors for Graves’ disease?
- Heat intolerance
- Sweating
- Weight loss
- Palpitations
- Tremor
- Diffuse goitre
- Orbitopathy
What is the treatment for Graves’ disease?
Antithyroid drug therapy such as carbimazole or thiamazole
What is Hashimoto’s thyroiditis?
Autoimmune-mediated lymphocytic inflammation of the thyroid gland resulting in a destructive thyroiditis with release of thyroid hormone and transient thyrotoxicosis (hyperthyroidism)
What is Hashimoto’s thyroiditis also known as?
Lymphocytic thyroiditis
What are the key diagnostic factors of Hashimoto’s thyroiditis?
- Heat intolerance
- Nervousness
- Small non-tender goitre
- Tremulousness
What is the treatment for a moderate/severe thyrotoxic phase of Hashimoto’s thyroiditis?
Beta-blocker/calcium-channel blocker plus corticosteroid e.g. atenolol/verapamil and prednisolone
What can low levels of parathyroid hormone indicate?
- Hypoparathyroidism
- Cancer that has spread to the bones
- Excess calcium
- Sarcoidosis
- Low magnesium
- Vitamin D toxicity
What drug belongs to the class biguanides?
Metformin
How do biguanides work?
- Increasing insulin sensitivity
- Increasing glucose uptake by cells therefore reducing plasma glucose concentrations
- Decreasing liver gluconeogenesis
What are alpha-glucosidase inhibitors and how do they work?
A class of diabetes medication that stop blood glucose levels rising too fast after eating
What is an example of an alpha-glucosidase inhibitor?
Acarbose
What are gliptins?
DPP-4 inhibitors used to treat type 2 diabetes
How do gliptins work?
1) Blocks DPP-4
2) Increases activity of incretins
3) Incretins stimulate insulin release and inhibit glucagon release
4) Blood glucose is lowered
What are sulfonylureas and how do they work?
A class of drug used to treat type 2 diabetes. They work by increasing the amount of insulin produced by the pancreas
What are two examples of sulfonylureas?
- Gliclazide
- Glimepiride
