Group Teaching - Disorders of Appetite

Question 1

Define polydipsia.

Answer 1

Excessive thirst or excess drinking

Question 2

Define adipsia.

Answer 2

Inappropriate lack of thirst

With consequent failure to drink in order to correct hyperosmolality

Question 3

Define anorexia.

Answer 3

Lack or loss of appetite for food

Question 4

Define obesity.

Answer 4

Abnormal or excessive fat accumulation that presents a risk to health

Question 5

What is the name of the hormone responsible for the regulation of Osmolality?

Answer 5

Antidiuretic hormone (ADH) or vasopressin

Question 6

How does ADH work and where is it stored?

Answer 6

• Acts on the kidneys to regulate the volume & osmolality of urine
  
  • Collecting duct - Aquaporin 2 channel
• In the posterior pituitary

Question 7

If the plasma concentration of ADH is low will there be a water diuresis or an anti-diuresis?

Answer 7

Diuresis

Question 8

Which regions are sensory osmoreceptors found in the hypothalamus (2 answers)?

Answer 8

• Organ vasculosum of the lamina terminalis (OVLT)
• Subformical organ (SFO)

Question 9

Please list at least 3 causes of primary polydipsia:

Answer 9

• Mental illness - psychogenic polydipsia (or acquired)
  
  • Schizophrenia
  • Mood disorders - depressionandanxiety
  • Anorexia
  • Drug use
• Brain injuries
• Organic brain damage

Question 10

Can you list at least 5 conditions that lead to secondary polydipsia?

Answer 10

• Chronic conditions
  
  • Diabetes insipidus & mellitus
  • Kidney failure
  • Conn’s syndrome
  • Addison’s disease
  • Sickle cell anaemia
• Medications
  
  • Diuretics
  • Laxatives
    
    • Both result in dehydration
  • Antidepressants
• Dehydration
  
  • Acute illness
  • Sweating
  • Fevers
  • Vomiting
  • Diarrhoea
  • Underhydration

Question 11

Mr Smith is 48 year old gentleman who works as an accountant. He recently noticed a wound on his shin that does not seem to be healing very well and he has also lost some weight. He has to interrupt his meetings frequently as he must go to the toilet to pass urine. His relationship with his wife at home is not what it used to be.

What do you think is wrong with Mr Smith?

Answer 11

T2DM

Question 12

Mrs Smith is an 84 year old lady who retired following multiple coronary angioplasties. She used to enjoy a walk in the park but now gets severe shortness of breath walking around her house. The Doctor has prescribed some medication for this. She is a little forgetful and finds it difficult to answer her granddaughters text messages. Her daughter has noticed that lately, despite drinking a large amount of water, her lips are always dry.

Why does Mrs Smith drink so much water and why are her lips dry?

Answer 12

High medication dose / Taking too much medication

Question 13

Mr Thomas is a 45 year old gentleman with significant abdominal obesity and type 2 diabetes. He has tried dieting before without much success. The nurse measures his height and weight which demonstrates a BMI of 39 kg/m².

What therapy would you recommend to Mr Thomas to treat his obesity and diabetes?

Answer 13

Bariatric surgery

Question 14

Put the following terms in the appropriate blue boxes in the diagram below:
* ANGIOTENSIN II
* ACE (angiotensin converting enzyme)
* RENIN
* ANGIOTENSIN I
* ADH secretion
* ALDOSTERONE
* H₂O retention via Na⁺CL^- absorption and K⁺ excretion
* Conn’s syndrome

Answer 14

1. RENIN
2. ANGIOTENSIN I
3. ACE
4. ANGIOTENSIN II
5. Conn’s syndrome
6. ALDOSTERONE
7. H₂O retention via Na⁺CL^- absorption and K⁺ excretion
8. ADH secretion