Show:
Physiology
Causes of vitamin D deficiency
Diagnosis
Management
100

Where can you get vitamin D from?

Created in the skin from sunlight, and directly from diet

100

When is sunlight-induced vitamin D synthesis is most effective?

UK spring and summer months, around midday

100

Name 3 symptoms of vitamin D deficiency

  • Fatigue
  • Bone pain
  • Muscle weakness
  • Muscle aches
  • Pathological or abnormal bone fractures
100

What lifestyle advice can be offered for patients with vitamin D deficiency?

Go outside in sun for short periods, advise on dietary intake of calcium and vitamin D

200

Where is vitamin D activated in the body?

In the kineys

200

What are three risk factors for vitamin D deficiency?

  • Living somewhere with lower sunlight
  • Winter months, when there is less sunlight and less time outside
  • Spending more time indoors (e.g., indoor occupations and care home residents)
  • Darker skin (those with darker skin require more sun exposure to create the same vitamin D)
  • Wearing clothes that reduce sun exposure on the skin
  • Older age (vitamin D production is less efficient with age)
  • Malabsorption (e.g., inflammatory bowel disease) affecting vitamin D absorption


200

What is the difference between osteoporosis and osteomalacia?

One is characterised by loss of bone density and mass whereas the other is softening of the bones

200

What type of vitamin D is used to treat vitamin D deficiency?

vitamin D3

300

How does calcitriol affect PTH?

Inbibits Parathyroid hormone (PTH)

300

Which GI conditions make you prone to vitamin D deficiency?

Malabsoprtion: crohns, UC

300

What does the standard blood test to check vitamin D levels measure?

25-hydroxyvitamin D?

300

Who does NICE recommend should be taking prophylactic vitamin D supplements?

Under 4 years or over 4 years old with risk factors

400

Which enzyme converts 25-hydroxyvitamin D (calcidiol) into 1,25-dihydroxyvitamin D (calcitriol) (the active form of vitamin D)?

1-alpha hydroxylase

400

State 3 things in a vitamin D rich diet?

Egg yolk, oily fish (such as salmon, mackerel, herring, and sardines), wild mushrooms, red meat, fat, liver, and kidney

400

Give 2 examples of what other lab investigations may show in vitamin D deficiency

  • Low serum calcium
  • Low serum phosphate
  • High serum alkaline phosphatase
  • High parathyroid hormone
400

How do you treat patients with vitamin D deficiency where rapid correction is needed?

Prescribe a fixed loading dose of vitamin D3 followed by regular maintenance vitamin D therapy 1 month after loading. [NICE]

500

How can low calcium levels affect the parathyroid gland? 

It can cause secondary hyperparathyroidsm

500

Why does severe CKD cause vitamin D deficiency?

Impairs the conversion of 25-hydroxyvitamin D (calcidiol) to the active form of vitamin D, 1,25-dihydroxyvitamin D (calcitriol). 


A blood test may show a normal level of 25-hydroxyvitamin D, while the active form, calcitriol, is deficient

500

List 2 differential diagnoses of vitamin D deficiency

Malignancy, fibromyalgia, fracture, hyperparathyroidism, polymyalgia rheumatica

500

Do you need to routinely monitor serum 25-hydroxyvitamin D  levels in patients with vitamin D deficiency?

No