Endocrinology Flashcards
For the following glands (exocrine or endocrine) explain whether they are:
A. Duct or Ductless
B. Release hormones directly into the blood or not?
Exocrine: Have ducts that transport to the site of the action such as the parotid gland
Endocrine: Don’t have ducts and release hormones directly into the blood (thyroid and adrenal glands)
Give an example of a peptide hormone?
- Insulin
Give an example of an amine hormone?
Dopamine and adrenaline
Give an example of an iodothyronine hormone?
Thyroxine
What is an example of a cholesterol hormone?
Oestrogen or Vit D
Where do peptide hormones act?
Cell membrane
What are two hormones that act on the nucleus of a cell ?
Thyroid hormone
Oestrogen
What 6 peptide hormones are produced by the anterior pituitary?
LH FSH TSH ACTH Prolactin GH
What two hormones are produced by the posterior pituitary gland?
ADH
Oxytocin
What inhibits the secretion of prolactin?
Dopamine
What is the imaging of choice to use in a patient with a suspected pituitary tumour?
MRI
What is the
Fasting level of glucose
Random level of glucose- needed for a diagnosis of Diabetes Mellitus?
Fasting >7.0
Random >11.1
What cell is insulin released from?
B cells in the pancreas
Describe what are the actions of the following Glucose Transporter Channels?
Glut 1
Glut 2
Glut 3
Glut 4
Glut 1: non insulin stimulated glucose uptake into cells
Glut 2: found in the beta cells of the pancreas. Detects high levels of glucose and release insulin in response
Glut 3: non insulin mediated glucose uptake in the brain
Glut 4: peripheral action of insulin. In muscle and adipose
Give 3 secondary causes of Diabetes?
Pancreatitis
Cushing’s Disease
Haemochromatosis
What is the triad for presentation of a patient with Type 1 Diabetes?
Weight loss + fatigue
Polydipsia
Polyuria
What is seen as a sign in patients who have severe insulin resistance?
Seen in neck and axillae of patients with insulin resistance.
You get acanthosis nigricans
What value does the HbA1c need to be to get diagnosed with T2DM?
HbA1c > 48
What is the pathophysiology behind diabetic ketoacidosis?
- SO you get autoimmune breakdown of the beta cells in the pancreas. This leads to less insulin made.
- You get breakdown of glycogen in the liver. High glucose causes dehydration.
- Peripheral lipolysis leads to increased FFA that are broken down to make acetyl co A which is converted to ketones in the mitochondria.
- Leads to metabolic acidosis with respirator compensation
What is normally found in a person with T2DM pancreas?
Amyloid deposits in beta cells due to an increase in pro inflammatory markers.
What are the two principles behind the pathophysiology of Type 2 DM?
- Insulin resistance
2. Insulin deficiency
What class of drug is metformin part of ?
- Biguanide
What is the pharmacology behind orlistat?
Intestinal lipase inhibitor
What are some of the symptoms of hypoglycaemia?
HE IS TIRED
headache Irritability Sweating Tachycardia Impaired vision Restlessness Excessive hunger Dizziness
What is the value of glucose for a diagnosis of Hypoglycaemia?
< 4.00
How would you manage someone with hypoglycaemia?
- If conscious give fast acting carb: sugar or fruit juice (CI in CKD and low K+ diets)
- Repeat after 10 mins up to 3 times
- Not responding give IM glucagon or IV glucose 10%. This is the same management if the patient is found unconscious
What is hyperosmolar hyperglycaemic state?
This is associated with type 2 diabetes.
RF: infections, steroids and thiazide diuretics.
They are still producing insulin but insufficient amounts to prevent hepatic glucose production
How would someone with hyperosmolar hyperglycaemic state present?
- Severe dehydration
- Decreased consciousness
- Symptoms of hyperglycaemia.
- The Hyperosmolarity predisposes them to MI, stroke etc.
What will the level of K+ be like in a patient with hyperosmolar hyperglycaemic state?
- LOW K+ level
How would you manage a patient with hyperosmolar hyperglycaemic state?
- IV fluids
- LMWH to reduce the risk of thromboembolism
- Replace lost K+ ions
Why is it needed for a patient with hyperosmolar hyperglycaemic state to be started on a LMWH like enoxoparin?
They are in a hyperosmolar state. Meaning they have a hypercoag state so at increased risk of thromboembolism
What diabetic medication should you avoid in people with diabetic nephropathy? + why?
Metformin
Increased risk of lactic acidosis
What is the best test for assessing whether a person has diabetic nephropathy?
Urine albumin: creatinine ratio >3
Explain the presentation differences between a patient who has a neuropathic foot ulcer vs a patient who has a neuro ischaemic foot?
Neuropathic Foot: warm, dry with bounding pulses. With reduced sensation
Neuroischaemic foot: cool and pink with atrophic skin and absent pulses
What is the other name used for Charcot Foot?
What are 3 factors that trigger Charcot foot?
- Neuropathic joint
2. Mechanical Vascular and Biological Factors
How would a Charcot joint normally present?
What imaging would you want to do?
It would normally present with a red, warm, swollen, deform foot.
Will have pain- but due to neuropathy will be a lot lower than expected
X-Ray and MRI scan
How do you treat Charcot Foot ? 3 ways
- Take weight off of the foot
- Treat the bone disease with Vit D and Bisphosphonates
- Surgery
Is Charcot foot an emergency?
YES
Why do you need to check LFTs in a patient with diabetes?
They have an increased incidence/risk of NAFLD and NASH.
What are two things you would test a diabetic’s urine for?
Microalbuminuria
Proteinuria
Mx of Diabetics in Surgery:
Elective (good control)
Elective (poor control) or fasting
Emergency Surgery
Elective (good control) normal levels given. Unless on LA and a 20% reduction is given.
Elective (poor control) or fasting: variable rate of insulin infusion. Until eating and drinking normal. Alongside KCL + glucose + NaCl
Emergency Surgery: IV fluids and insulin. But check the ketones, BG constantly
What happens in the colloid of the thyroid gland?
In the colloid you get iodine molecules binding to tyrosine
To great T1 or T2
This makes T3 or T4 (thyroxine)
It then once stimulated by TSH moves into secretory cells.
Would you be more concerned about a diffuse or nodular thyroid lump?
Nodular: associated with adenomas, cysts and cancer
Diffuse is normally just associated with goitres etc.
What are 4 common causes of hyperthyroidism?
Grave’s Disease
Toxic multinodular goitre or toxic adenoma
Drug induced hyperthyroid: iodine, lithium or amiodarone
De Quervain’s thyroiditis: normally secondary to infection.
What is De Quervain’s Thyroiditis?
Transient inflammation of the thyroid normally secondary to acute viral infection.
You get malaise, fever and a pain in the neck.
How do you treat DQ thyroditis?
Aspirin
Prednisolone
What might you find on blood investigations of a patient with hyperthyroidism?
TSHR- ab if Graves’ disease
Low TSH and high T3 and high T4
How do you manage hyperthyroidism?
- BB propranolol
- Carbimazole if ? Hypo after a time you can start them on thyroxine as well.
- Radioactive iodine therapy
- Surgery
What does Graves’ disease do to the eyes?
It causes retro orbital inflammation.
Presents as exophthalmos, photophobia, eye pain and Diplopia
What skin changes can you get in Graves’ disease?
Pre tibial myxoedema
What is the management of an acute presentation of graves eye disease?
IV methyl pred
Surgical decompression
What is thyrotoxicosis?
This is when you have excess thyroid hormone in the blood
sx: tachycardia, restlessness, hyperpyrexia and delirium/coma
How do you manage thyrotoxicosis?
Carbimazole
Propranolol
Potassium iodide
IV hydrocortisone
What are the two major causes of hypothyroidism?
- Iodine deficiency
2. Autoimmune conditions such as hashimoto
Give some signs of Hypothyroid?
BRADYCARDIC
Bradycardia Reflex slow Ataxia Dry (thin hair and skin) Yawning and drowsy Cold hands Ascites Round puffy face Defeated demeanour Immobile lieu’s Congestive cardiac failure
What antibodies are present in a patient with hashimoto disease?
TPO antibodies
What is a myoedema crisis?
How do you manage it?
This is when you have severe hyperthyroidism that can cause confusion and coma , cardiac failure, hypoglycaemia etc.
Management: IV T3, glucose infusion and gradual rewarming
What is the most common type of thyroid cancer in young people?
Papillary
What is the most common thyroid cancer in middle age people?
Follicular
Where can thyroid cancer throw mets to?
Bone and Lungs
How do most people present when they have thyroid cancer?
Thyroid nodule or lump hard and irregular in shape
Dysphagia and hoarseness of voice (due to compression of the recurrent laryngeal nerve)
What is the diagnostic method use for thyroid cancer?
TFTS
US
Fine needle aspiration
How do you treat thyroid cancer?
- Radio iodine therapy
- Admin lots of levothyroxine
- Surgery
What are the 3 layers of the adrenal cortex? What do each of them produce?
GFR?
Zona Glomerulosa: mineralcorticoids like aldosterone
Zona Fasciulata: glucocorticoids like cortisol
Zona Reticularis: sex hormone like androgens
What is made in the adrenal medulla?
Epinephrine and norepinephrine