Dermatology: Functions of the Skin

Question 1

Functions of the skin?

Answer 1

Barrier functions

Metabolism and detoxification

Thermoregulation

Immune defence

Communication

Sensory functions

Question 2

Consequences of acute skin failure?

Answer 2

Loss of barrier increases infection risk, water loss and disturbs thermoregulation

Question 3

Example of when acute skin failure occurs?

Answer 3

Toxic epidermal necrolysis

Question 4

What is ichthyosis?

Answer 4

A group of genetic disorders causing thick, dry, fish scale like skin, e.g: there is an X-linked form that occurs in males

Question 5

What is erythroderma?

Answer 5

Inflammatory disease involving erythema and scaliness

Question 6

Functions of skin in relation to metabolism and detoxification?

Answer 6

Vitamin D metabolism

Thyroid hormone metabolism

Defence against chemicals, drugs, pollutants and sunlight

Question 7

Vitamin D conversion and storage?

Answer 7

UV allows cholecalciferol to be converted to vitamin D3, which is stored as hydroxycholecalciferol in the liver

This is then converted to 1,25-dihydroxycholecalciferol (an even more active form) in the kidney

Question 8

Thyroid hormone metabolism?

Answer 8

Thyroxine (T4) is converted to triiodothyronine (T3); 20% of this occurs in the thyroid gland and 80% in the peripheral tissues, inc. skin

Question 9

What are Scabies?

Answer 9

Mite burrows into keratin layer

Question 10

What is eczema herpeticum?

Answer 10

Disseminated herpes simplex virus infection; usually occurs in people with a tendency towards asthma, eczema and hayfever