Gastroenterology (Nutrition)

Question 1

Fat-soluble vitamins

Answer 1

• Vitamin A
• Vitamin

may accumulate in the body, such as in the liver:

Question 2

Water-soluble vitamins

Answer 2

more readily excreted from the body, therefore toxicity is generally less likely:
* Vitamins B1, B3, and B6
* Vitamin C

Question 3

Vitamin A deficiency can lead to:

Answer 3

also known as retinol

• Xerophthalmia – describes a spectrum of pathologies affecting the conjunctiva, cornea, and retina, including night blindness and corneal scarring

Question 4

vitamin A caution

Answer 4

• High doses of vitamin A may be teratogenic:
• This is because retinol converts to retinoic acid, which can lead to congenital defects if levels are too high or low
• Foods with liver have high vitamin A levels and should be avoided during pregnancy

Question 5

vitamin B1 (thiamine) deficiency occurs due to

Answer 5

• Alcohol excess:
• Due to alcohol inhibiting the uptake of thiamine
• Malnutrition

Question 6

B1 (thiamine) deficiency can lead to

Answer 6

• Wernickes
• Korsakoff sydrome
• Beriberi

Question 7

wet vs dry Beriberi

Answer 7

Wet beriberi – describes dilated cardiomyopathy:

• Tachycardia
• Elevated jugular venous pressure
• Paroxysmal nocturnal dyspnoea
• Shortness of breath on exertion
• Peripheral oedema

Dry beriberi – describes peripheral neuropathy:

• Numbness and tingling
• Confusion
• Hyporeflexia

Question 8

deficiency in vitamin B3 (iacin)

Answer 8

A deficiency of B3 can lead to pellagra which is characterised by:

• Dermatitis
• Dementia
• Diarrhoea
• Hair loss
• Photosensitivity
• Glossitis
• Weakness

Question 9

vitamin B6 (pyridoxine) deficiency

Answer 9

peripheral neuropathy

• Isoniazid – used in tuberculosis
• Penicillamine – used in Wilson’s disease
  *

Question 10

vitamin C deficiency

Answer 10

Reduced vitamin C can lead to scurvy, which occurs secondary to impaired wound healing and collagen synthesis. Features include:

• Easy bruising and ecchymosis
• Poor wound healing
• Gingivitis bleeding gums
• Weakness
• Malaise
• Anorexia
• Depression
• Synovitis
• Cautions

Scurvy is exceedingly rare in the UK. Patients with these features may have an underlying haematological malignancy, therefore, investigations should not be delayed by a trial of vitamin C treatment.

Question 11

Vitamin C deficiency occurs in

Answer 11

• People whose exposure to sunlight is limited (e.g. those that are housebound, confined indoors, or cover their skin)
• People with dark skin as their skin is less efficient at synthesising vitamin D
• Pregnant and breastfeeding women
• Children under 4 years of age
• Intestinal malabsorption
• Chronic liver disease

Question 12

vitamin D deficiency

Answer 12

• rickets
• osteomalacia

Question 13

vitamin K

Answer 13

important for clotthing factors II, VII, IX AND X
- found in green vegetable and olive oil

Question 14

vitamin K deficiency

Answer 14

Deficiency

Since vitamin K is fat-soluble, patients with fat malabsorption (such as biliary obstruction or hepatic disease) are at an increased risk of deficiency.

• Coumarin anticoagulants (such as warfarin) exert their effects by interfering with vitamin K metabolism).
• Vitamin K deficiency can lead to:
• Excessive bleeding
• Haemorrhagic disease of the newborn

Question 15

RF for malnutrition in elderly

Answer 15

Living alone, particularly without care input
Institutionalisation
Hospitalisation
People with mental health problems
Diseases affecting appetite, eating, swallowing, or gastrointestinal function

Question 16

RF for malnutrition in young

Answer 16

Young age
Children with co-existing illnesses
Neglect
Poverty

Question 17

People are considered to be malnourished if any of the following apply:

Answer 17

1. A BMI of less than 18.5 kg/m2
2. Unintentional weight loss >10% in the last 3-6 months
3. BMI of less than 20 kg/m2 and unintentional weight loss >5% in the last 3-6 months

Question 18

People are considered to be at an increased risk of malnutrition if any of the following apply:

Answer 18

1. They have eaten little or nothing for >5 days and/or are likely to eat little or nothing for the next 5 days or longer
2. Have poor absorptive capacity and/or high nutrient losses and/or increased nutritional needs due to causes such as catabolism

Question 19

screening tool for malnutrition

Answer 19

MUST

Question 20

pathophysiology of Reefeeding syndrome

Answer 20

Pathophysiology

In starvation, insulin secretion is decreased due to reduced carbohydrate intake and fat and proteins are catabolised to release energy. This leads to an intracellular loss of electrolytes, particularly phosphate, magnesium, and potassium.

When feeding restarts, the shift from fat and protein to carbohydrate metabolism increases insulin secretion, which stimulates cellular uptake of phosphate and other electrolytes, leading to severe hypophosphataemia, hypokalaemia, and hypomagnesaemia. Phosphate is essential for the formation of ATP and other phosphorylation reactions, leading to cellular dysfunction.

Question 21

Patients are deemed at high risk of refeeding syndrome if:

Answer 21

1 or more of the following are present:

• BMI less <16 kg/m2
• Unintentional weight loss greater than 15% within the last 3 to 6 months
• Little or no nutritional intake for more than 10 days
• Low levels of potassium, phosphate or magnesium before feeding

Or 2 or more of the following apply:

• BMI less than 18.5 kg/m2
• Unintentional weight loss greater than 10% within the last 3 to 6 months
• Little or no nutritional intake for more than 5 days
• A history of alcohol abuse or drugs including insulin, chemotherapy, antacids or diuretics

Question 22

presentation of refeeding syndrome

Answer 22

• Hypophosphataemia
• Hypokalaemia
• Hypomagnesaemia
• Features of Wernicke-Korsakoff encephalopathy (due to thiamine deficiency)
• Hyperglycaemia – due to abnormal glucose metabolism and reduced insulin secretion
• Cardiac arrhythmia – due to electrolyte imbalances
• Fluid imbalances
• Pulmonary oedema
• Heart failure

Question 23

prevention of refeeding syndrome

Answer 23

• Initiate feeding at no more than 50% of energy in patients who have eaten little or nothing for more than 5 days, then increase if no refeeding problems are detected on clinical or biochemical testing
• Electrolyte levels are checked once daily for 1 week then at least 3 times in the following week

Question 24

refeeding is a biochemical triad of

Answer 24

1. Hypophosphataemia
2. Hypokalaemia
3. Hypomagnesaemia