Endocrinology Tutorials

Question 1

What are the causes of short stature?

Answer 1

• Genetics (Parents/ genetic conditions such as Down syndrome)
• Malnutrition or emotional deprivation
• Lack of growth hormone
• Cushings (excess steroid hormone(
• Bone abnormalities

Question 2

How can you design a growth hormone stimulation test?

Answer 2

• Insulin tolerance test (measure growth hormone following insulin injection)
• Vigorous exercise
• Large intake of amino acid high food
• Somatotropin releasing hormone

Question 3

What is the renal threshold?

Answer 3

When blood sugar increases over 10mmol/litre the kidney can’t prevent glucose passing into the urine. This is why patients with diabetes have glucose in their urine.

Question 4

What is osmotic dieresis?

Answer 4

Where glucose moves into the urine and water follows, as water potential of the urine is decreased.

Question 5

What surrogate marker of insulin can be measured?

Answer 5

The levels of C peptide in the blood. This is the same as insulin levels.

Question 6

What causes tiredness in Addisons?

Answer 6

Low levels of sodium (hyponatraemia), and low cortisol

Question 7

How can diabetes be diagnosed?

Answer 7

• Test for fasting blood glucose above 7mmol
• Test for HbA1c. This is possible as glucose binds irreversibly to blood cells, so the number of blood cells bond to glucose can be calculated, allowing blood sugar to be predicted for the last 3 months.

Question 8

Why do patients with cushings syndrome develop type 2 diabetes?

Answer 8

Cortisol encourages gluconeogenesis, as well as weight gain around the stomach

Question 9

How is proximal myopathy diagnosed?

Answer 9

The patient is asked to squat and stand up without using their arms

Question 10

List the clinical signs of cushings

Answer 10

• Abdominal striae (purple stretch marks)
• Plethoric face (red)
• Round face
• Buffalo hump
• Central obesity

Question 11

What medications can cause excess cortisol?

Answer 11

• Inhalers for asthma
• Steroid creams
• Skin lightening creams

Question 12

What are the symptoms of a prolactinoma?

Answer 12

• Inhibits LH and FSH
• Galactorrhea (milk release from breasts)
• Ogliomenorrhea (erratic periods)
• Loss of peripheral vision
• Headaches

Question 13

Why does a prolactinoma cause a bitemporal hemianopia?

Answer 13

• The optic nerves have four parts. The nasal parts cross over around where the pituitary gland is.
• A tumour of the pituitary gland compresses these nerves and causes loss of vision at the outer parts of the visual field

Question 14

Why does a prolactinoma cause loss of periods?

Answer 14

• Prolactin levels are mainly high when breastfeeding. This means the woman has a young baby.
• It is not evolutionary beneficial to have another baby so soon, so sex hormones are inhibited