Random Endo/ Pituitary Function

Question 1

What are the blood glucose and HbA1clevels for diabetes diabetes?

Answer 1

1. Fasting plasma Glucose >7mM
2. Glucose Tolerance Test: 2h after >11.1 mM
3. HbA1c >6.5% (48mmol/ml)

Question 2

What are causes of metabolic alkalosis?

Answer 2

1. H+ loss
2. Hypokalaemia
3. ingestion of Bicarbonate

Question 3

What is Osmolality?
How does it differ from osmolarit?

Answer 3

** Osmolarity** = calculated, units = mmol/l

Osmolality = total number of particles in solution - measured with an osmometer, units = mmol/kg.

Question 4

What particles are the main determinants of Serum Osmoarity?

Answer 4

Physiological = Na+ K+ Cl + HCO3 + urea + glucose

Pathological = Endogenous (i.e. glucose), Exogenous (ethanol, mannitol)

Question 5

What is the normal range for serum osmolarity?

Answer 5

275 – 295 mmol/kg

Question 6

How would you calculate osmolality?

Answer 6

2 (Na+K) + Urea + Glucose

Question 7

How does alkalosis cause hypokalaemia?

Answer 7

To restore pH –> H+ will move from cells into extrcellular fluids in exchange for K+ –> hypkalaemia

Question 8

How does Hypokalaemia cause Alkalosis?

Answer 8

In Hypokalaemia

K+ is going from cells into the bloodstream in exchange for extracellular Hydrogen ions (–> H+ moves into the cells) –> Hypokalaemia

Question 9

What diagnosis is suspected if the pt is not pregnant and has a prolactin of >6.000?

Answer 9

Prolactinoma

Question 10

What is done in a pituitary function test?

Answer 10

Stimmulation of hormone secretion:

Administer LHRH, TRH and stress via Hypoglycaemia (<2.2mmol/L)

Hypoglycarmia –> increase CRF and ACTH and GH

Question 11

How is a Combine pituitary function test done?

Answer 11

Fasting over night
* Give IV 0.15U/kg insulin
* TRH 200mcg
* LHRH 100mcg

And Measure
* glucose
* Cortisol
* GH
* LH, FSH and TSH 30 mins and max 60 mins after

AND measure
* Glucose
* GH and
* cortisol
* Every 30 mins until 120 mins

Question 12

How is pituitary malfunction treated?

Answer 12

• Hydrocortisone replacement
• Thyroxine replacement
• Oestrogen replacement
• GH replacement

Question 13

How is pituitary adenoma treated?

Answer 13

Cabergaline
Bromocriptine
(Dopamine agonists –> shrink) +/- surgery

Question 14

How can a non-functioning pituitary adenoma cause prolactinaemia?

Answer 14

Adenoma –> compression of pituitary stalk –> Inhibition of dopamine signaling –> increased prolactin

Question 15

What enzyme has reduced activity in Gilbert’s syndrome?

Answer 15

UDP glucuronyl transferase