Eating Disorders

Question 1

What test can be used to assess muscle wasting in patients with anorexia nervosa:

Answer 1

The sit-up–squat–stand (SUSS) test is a method used to assess muscle wasting in patients with anorexia nervosa. In the sit-up test, the patient lies flat on a firm surface such as the floor and attempts to sit up without using their hands. In the squat test, the patient is asked to rise from a squatting position without using their hands.

An inability to stand up from a chair without using their hands indicates failure of the squat test, which is a red-flag sign indicating severe muscle wasting.

Question 2

what investigations should be done in suspected anorexia nervosa?

Answer 2

• Basic obs (BP: hypotension)
• Full examination, height and weight – look for signs of anorexia/malnutrition: tired, sunken cheeks, clothing baggy, peripheral cyanosis, cold fingers, lanugo hair
• May consider USS of ovaries (amenhorrea)
• Urine pregnancy test
• Bloods – FBC, TFTs, U&Es (hypokalaemia, hypophosphataemia and hypomagnesiumaemia), Low sex hormone levels (FSH, LH, oestrogen and testosterone), lipid profile (Hypercholesterolaemia),
  Raised growth hormone and cortisol levels
• ECG (bradycardia, with symptoms such as dizziness, fainting or light-headedness, prolonged QT interval. A prolonged QT interval increases the risk of a fatal arrhythmia such as Ventricular Fibrillation)

Question 3

physical features in anorexia nervosa:

Answer 3

Low BMI
Hypotension
Bradycardia
Enlarged salivary glands
Lanugo hair (fine hair covering the skin)
Amenorrhoea

Question 4

Biochemical results in anorexia: (mnemonic)

Answer 4

-most things low (eg potassium, WCC: high secondary to malnutrition, Hypokalaemia
Hypomagnesemia,
Low sex hormone levels (FSH, LH, oestrogen and testosterone)

except high Gcs and Cs: Growth hormone, salivary glands, glucose (normal or low), hypercarotinaemia, hypercholesterolaemia, cortisol

Question 5

A 21-year-old female is being treated for anorexia nervosa. She has been suggested a drug treatment that could help with her anxiety around food and help her regain the weight needed to achieve a healthy weight to be discharged.

What drug has most likely been recommended?

Answer 5

Olanzapine is a form of atypical antipsychotic drug. The main side effects associated with these drugs are sedation, QT interval prolongation and metabolic disturbances (weight gain). This side effect of weight gain means it is a commonly used drug to help those who are underweight achieve weight gain goals.

Question 6

metabolic disturbances in purge-type bulimia:

Answer 6

Hypokalaemia with metabolic alkalosis is seen in patients who have frequently been vomiting either due to bulimia or due to an organic cause such as norovirus. Vomiting induces the renin–angiotensin–aldosterone steroid (RAAS) system to activate, retaining sodium, bicarbonate and water and expelling potassium. The use of diuretics also further reduces levels of potassium in the body, leading to a hypokalaemic state with metabolic alkalosis.

Question 7

features of bulimia:

Answer 7

It is characterized by:

1. Binge eating: Loss of control, eating enormous amounts with thousands of calories, often in sense of urgency and compulsion
   2, Purging: binges causes feelings of shame and guilt leading to attempts to ‘undo damage’ vomiting, laxatives, diuretics, can also be exercise
2. Body image distortion: feeling fat, often hate their body
3. BMI > 17.5 (usually normal or slightly increased weight and periods usually present)

Physical features:
1. dental erosion
2. parotid gland swelling
3. Russel’s sign (scarring on knuckles from induced vomiting)

Question 8

1st line management for eating disorders:

Answer 8

ED-focused CBT (referred for specialist care)

Question 9

what is refeeding syndrome?

Answer 9

Refeeding syndrome describes the fatal metabolic abnormalities which occur on feeding a person following a period of starvation. It occurs when an extended period of catabolism ends abruptly with switching to carbohydrate metabolism. The metabolic consequences include:
1. hypophosphataemia
2. hypokalaemia
3. hypomagnesaemia: may predispose to torsades de pointes
4. abnormal fluid balance

It is potentially fatal, as arrhythmias, cardiac failure and seizures can develop.