derm 2

Question 1

• Give 6 of the functions of the hair

Answer 1

Protection against external factors

Sebum

Apocrine sweat

Thermoregulation

Social and sexual interaction

Epithelial and melanocyte

Question 2

• What are the two types of hair?

Answer 2

Terminal hair → Scalp, eyebrows and eyelashes

Vellus hairs → Rest of body except for: palms, soles, mucosal regions of lips and external genitalia

Question 3

• What are the 3 steps of the hair cycle and what happens in each of them?

Answer 3

Anagen - whwere new hair forms and grows

- 85% of hair; lasts 2-6 years

Catagen - regressing phase

- 1% of hair; lasts 3 weeks

Telogen - resting phase

- 10-15% of hair; lasts 3 months

Question 4

• What is the pilosebaceous unit also known as?
• What is the function of the Arrector Pili?
• Where do the holocrine sebaceous glands open up into?

Answer 4

Hair follicle

Contracts to make the hair erect on the skin to generate heat

The pilary canal → in axillae

Question 5

• Where are apocrine glands found?
• What is the uppermost portion of the hair follicle called?
• What is the lower portion of the hair follicle called?

Answer 5

In the skin are in the armpits, the groin, and the area around the nipples of the breast

Infundibulum - extends from opening of sebaceous gland to surface of the skin

Isthmus - Between opening of sebaceous gland and insertion of arrector pili muscle

Question 6

• What is meant by keratinization?
• What does keratinization begin with?
• What is found in the Bulge of the hair?

Answer 6

The cytoplasmic events that take place in keratinocytes that move through the different layers of the epidermis to finally differentiate to corneocytes

epithelial keratinization begins with a lack of granular layer named trichilemmal keratinization

Hair follicle stem cells

Question 7

• Where and in what manner do these hair stem cells migrate?

Answer 7

Downward → generate the new lower anagen hair follicle → enter hair bulb matrrix, proliferate and undergo terminal differentiation to form hair shaft and inner root sheath

Upwards (distally) - form sebaceous glands and to proliferate in response to wounding

Question 8

what is the bulb of the hair follicle

what is the outer root sheath

what is the inner root sheath

Answer 8

lowermost portion of the hair follicle
includes hair matrix and follicular dermal papilla

extends along hair bulb to infundibulum and epidermis
serves as a reservoir of stem cells

guides/ shapes hair
encloses follicular dermal papilla , nerve fiber, a capillary root and mucopolysaccharide- rich stroma

Question 9

• Give 5 of the functions of the nails

Answer 9

Protection of underlying distal phalanx

Counterpressure effect to pulp important for walking and tactile sensation

Increase dexterity / manipulation of small objects

Enhance sensory discrimination

Facilitate scratching or grooming

Question 10

• Where does the nail plate emerge from?
• How fast does a nail grow?
• Where does the nail plate detach?
• What is the nail plate

Answer 10

Proximal nail fold

1-3mm/month

Hyponychium

Final product of the differentiation of the nail matrix keratinocytes

Question 11

• Where is the nail matrix found?
• What is the only visible portion of the nail matrix called?
• What occurs in the nail matrix?

Answer 11

Under proximal nail fold, above bone of distal phalanx- connected to it by tendon

Lunula

Karatinocytes differentiate → lose their nuclei and are strictly adherent - cytoplasm completely filled by hard keratins. also contains melanocytes

Question 12

• Is polygenic predisposition enough to contract Psoriasis?
• What is the most common form of Psoriasis characterised by?
• What are the common sites of involvement with Psoriasis?

Answer 12

No, environmental triggers are also needed

Sharply demarcated, scaly, erythematous plaques

Scalp, elbows and knees, followed by nails, hands, feet and trunk

Question 13

• What is the most common systemic manifestation of Psoriasis?

Answer 13

Psoriatic arthritis- psoriasis in nail matrix can lead to arthritis as nail bed is connected to distal phalange by a tendon

Question 14

• Why do scales form on the skin during Psoriasis?

- Why do you not see these same scales in Flexural Psoriasis?

Answer 14

The keratin differentiation process occurs so quickly due to increased kearatin proliferation that they do not differentiate correctly

The friction rubs it away as these tend to be in areas whereskin touches skin eg  the genitalia

Question 15

• Explain the pathophysiology of Psoriasis

Answer 15

Stressed keratinocytes release DNA/RNA which form complex with antimicrobial peptides (endogenous antibiotic - Psoriasin)

Induces release of cytokines - TNF-alpha, IL-1 and IFN-alpha

This activates dermal dendritic cells (dDCs)

dDcs migrate to the lymph nodes and promote Th1, Th17, Th22 cells

These release chemokines which cause the migration of inflammatory cells into the dermis

These inflammatory cells cause release of cytokines which lead to keratinocyte proliferation

This leads to a psoriatic plaque

Question 16

• Name three features seen in Nail Psoriasis?

Answer 16

Subungal hyperkeratosis - scaling of the nail coming from the nail matrix

    Onycholysis - nail lifts of nail bed

    Pitting - Keratinocytes forming the nail plate are inflamed and not sticking to the other keratinocytes effectively- holes in nail bed

Question 17

• When can the term ‘erythroderma’ be used to describe someone’s condition?
• What type of infection does Guttate Psoriasis typically follow?

Answer 17

When 90% or more of their skin is inflamed- functions of skin start to fail eg thermoregulation, barrier, immunological

Streptococcal throat infection

Question 18

• What is meant by secondary prevention of a condition?
• Give examples of some of these aggrevating fators that might aggravate Psoriasis
• What co-morbidities might Psoriasis increase your risk of contracting?

Answer 18

Minimisation or avoidance of the aggravating factors

Smoking and Alcohol consumption

Psoriatic Arthritis, Coronary Artery disease, Inflammatory Bone disease

Question 19

• Give an example of a type of treatment that is used to treat both inflammatory bowel disease and psoriasis?
• What are some of the 1st line treatments considered when treating Psoriasis?

Answer 19

Anti-TNF biologic treatments

Topical gels, creams, ointments and foams or phototherapy

Question 20

• What are some of the topical therapies that are used?

Answer 20

Vitamin D analgoues - calcipotriol

Topical coritcosteroids

Retinioids - Vitamin A analogues

Topical tacrolimus - T-cell inhibitors

Question 21

• What does phototherapy do?

- Why might phototherapy be considered over topical therapies?

Answer 21

Induces T-Cell apoptosis

Cream cannot be constantly applied all over the body and so when the psoriasis covers more than 20% of the body's surface area, phototherapy is used

Question 22

• Why would you be less likely to use PUVA over UVB?

- Is it the 2nd or 3rd line treatments that are systemic?

Answer 22

UVB does not cause an increased risk of skin cancer, whereas PUVA does

Both

Question 23

• What is Acitretin and why would it be used as a treatment for Psoriasis?

Answer 23

Oral retinoid - Vitamin A analogue

Retinoids help bring order to the differentiation of the keratinocytes from deep to superficial

Therefore it restores order of keratinization

Question 24

• Give 2 examples of immunosuppresive drugs ?

- What does Apremilast do?

Answer 24

Methotrexate, Ciclosporin

It is a Phosphodiesterase inhibitor and this allows reduction in the amount of TNF alpha

Question 25

- What are biologics when referring to the advanced treatments of Psoriasis

Answer 25

Injected monoclonal antibodies against TNF-alpha, IL-17 and IL-23

Question 26

- What are some of the other atopic disorders associated with atopic eczema? - Does flexural inflammation and lichenification occur in children or adults? - Where does acute inflammation occur in children with atopic eczema?

Answer 26

Rhinoconjunctivitis, Hay Fever, Asthma both Acute inflammation of cheeks, scalp and extensors

Question 27

- What does filaggrin do?

Answer 27

Binds and aggregates keratin bundles and intermediate filaments to form cellular scaffold in corneocytes

Question 28

- What role does Filaggrin play in the pathophysiology of eczema? (barrier defect)

Answer 28

A defect in the genes coding for the protein means that it cannot function correctly Which means that the stratum corneum cannot function correctly This means that the extracellular lipids and ceramide production at the stratum corneum are reduced Ceramide locks moisture into your skin and without this, there is a net effect of Transepidermal Water Loss (TEWL) This leads to impaired protection against microbes and environmental allergens

Question 29

- How can immune dysregulation lead to eczema?

Answer 29

Staphylococcal (Aureus) superantigens stimulate overactive Th2 lymphocyte responses and subvert T-reg Cytokine release leads to epidermal lichenification, spongiosis (odema in epidermis) , decreased filaggrin

Question 30

- What symptoms result from atopic eczema in children? | - Into adulthood, what symptoms are found due to atopic eczema?

Answer 30

Erythematous, oedematous papule and plaques with vesiculation Lichenification due to chronic scratching, exaggeration of the normal skin markings and disordered pigmentation

Question 31

what is fissuring what is impetiginisation

Answer 31

cracks in fingers due to water loss, reduced flexibility of the skin gold crust on fingers, caused by staphylococcus (more common) or streptococcus

Question 32

what conditions are under the umbrella term eczema dermatitis

Answer 32

atopic eczema seborrhoeic dermatitis venous stasis eczema allergic contact dermatitis irritant contact dermatitis

Question 33

- How would you describe an 'erosion'? - when you see many monomorphic erosions what condition does this suggest - What happens if this condition is left untreated?

Answer 33

Breaches in the epidermis that don't go all the way through (if they did, that would be an ulcer) Eczema herpeticum an emergency, more susceptible to herpetic infections It can be complicated by encaphilitis, blindness and can be fatal

Question 34

- What lifestyle modifications could be applied to manage atopic eczema?

Answer 34

Moisturise at least 3 times a day Omission of soap Habit reversal of scratching Clinical nurse specialist involvement for topical application technique

Question 35

- Why might patch testing be used to manage atopic eczema? | - If someone who has nipple eczema is not responding to treatment, why would you take a biopsy?

Answer 35

Patch testing is used to detect allergies These allergies could be what is aggrevating the eczema if treatment is not working on the eczema Paget's disease of the nipple is associated with underlying breast cancer which looks exactly the same as nipple eczema Could also be a skin lymphoma

Question 36

- What topical therapies can be given to manage eczema? - What case would PUVA be used in eczema management? - Is narrowband UVB still used as a treatment?

Answer 36

Topical corticosteroids - correct potency for correct site Topical tacrolimus / pimercrolimus - T-cell inhibitor Hand dermatitis Yes

Question 37

- Give examples of very rare or extremely rare adverse effects of topical corticosteroids? - Give examples of rare adverse effects of topical corticosteroids? - What is an extremely rare adverse effect of topical corticosteroids?

Answer 37

perioral dermatitis and rebound syndrome (tachyphylaxis) skin atrophy, exacerbation of acne and rosacea, and infection Hormonal imbalance (Suppression of hypothalamic-pituitary-adrenal axis) and hirsuitism

Question 38

- In what region of the body do retinoids work well against eczema in than others? - Give examples of systemic immunosuppressing drugs to treat eczema?

Answer 38

Hands Methotrexate, Ciclosporin, Azathioprine and Mycophenolate

Question 39

- What do the biologics that are used in eczema management target? - Give an example of one of these drugs - What other condition is dupilimab used for?

Answer 39

IL-4alpha, IL-13 Dupilimab Asthma