Dermatology - inflammatory skin conditions (eczema, psoriasis and acne)

Question 1

Eczema: name 4 types of eczema

Answer 1

Exogenous (external causative agent)

• Asteatotic eczema
• Irritant contact dermatitis
• Allergic contact dermatitis

Endogenous (no precipitant identified)
-Atopic eczema

Question 2

What is this condition? Describe symptoms, contributory factors and treatment

Answer 2

Asteatotic eczema

• Dry erythematous eczema with fissuring and cracking (‘cracked paving’ appearance)
• Often affects shins of elderly

Contributory factors

• Over washing of patients in institutions
• Dry winter climate
• Dehydration through use of diuretics

Treatment
-Emollients and avoid detergents

Question 3

What is this condition? Describe contributory factors and treatment

Answer 3

Irritant contact dermatitis - eczema will occur on exposured areas

Contributory factors

• Caused by external agents damaging skin: eg substances used in hospital/cleaning
• Most commonly occurs with chronic exposure: hand dermatitis from hand washing

Management

• Theoretically simple: remove agent from patient/protect skin agasint it
• Emollients and topical steroids can help calm skin

Question 4

What is this condition? Describe symptoms and how to establish a diagnosis

Answer 4

Allergic contact dermatitis

• Delayed hypersensitivity reaction to external agent, eg nickel, rubber and topical meds
• Presents ad dermatitis in typical areas or classical patterns which suggest the agent which caused it (eg around wrist or where rings go)

Diagnosis

• History + charting the chronology + site of reaction
• Patch testing by dermatologist

Question 5

What is this condition? Describe the PC

Answer 5

Atopic eczema

• Papules and vesciles on an erythematous base
• Commonly presents as itchy, erythematous dry scaly patches
• Infants: more common on face and extenxor aspects
• Children and adults: flexor aspects

Question 6

Name the feautres of the acute phase of eczema + associated features

Answer 6

Acute eczema:
-Erythema
-Oedema
-Papules
-Vesicles
-Exudation
*As chronicity approaches, the oedema lessens and epidermis becomes thickened (lichenification)

Associated features

• Scratch marks (itchy)
• Hyperpigmentation
• Secondary bacterial/viral infection

Question 7

How do you mange atopic eczema: maintenance

Answer 7

Maintenance aim: creature a barrier to compensate for defective skin

• Emollients and soap substitutes: E45, diprobase cream (thin)
• Avoid certain foods/washing soap/cleaning products

Question 8

How do you mange atopic eczema: flares

Answer 8

Aim: suppress overactive immune system

• Thicker emollients: driprobase ointment (can be used as ‘wet wrap’ overnight
• Topical steroids: mild (hydrocortisone 0.5-2.5%), moderate (eumovate 0.05%), potent (betnovate 0.05%) and very potent (dermovate 0.05%) +/- topical antibacterial AND/OR topical immunomodulators (tracrolimus)
• Oral therapies: antihistamines
• Severe non-responsive cases: UV therapy + Immunosuppression/modulatio: PO steroids

Question 9

Name some complications of eczema

Answer 9

• Secondary bacterial infection: usually staph aureus, treat with PO flucloxacillin or admit for IV abx
• Secondary viral ifnection: molluscum contagiosum, viral warts and eczema herpeticum

Question 10

Name some forms of psoriasis

Answer 10

• Classical plaque psoriasis: most common subtypre resulting in well demarcated red scaly patches affecting extensor surfaces and scalp
• Flexural psoriasis: in contrast to plaque psoriasis the skin in smooth
• Guttate psoriasos (raindrop lesions): transient psoriatic frequently rash triggered by a streptoccocal infection 2-4 weeks previously, most cases self resolve within 2-3 months
• Acute generalised pustular psoriasis: palmar-plantar psoriasis
• Erythrodermic (total body redness)

Question 11

What is this? Outline the symptoms

Answer 11

Plaque psoriasis
-Most common
-Single or multiple plaques with variation in size - plaques are usually red, scaly, have silvery surface, usually on extensor surfaces and scalp
-Nail changes: pitting or onycholysis (painless detachment of nail from bed)
-Scratch and gentle removal causes capillary bleeding.
*5-8% suffer from associated psoriatic arthropathy

Question 12

Outline the general management of psoriasis

Answer 12

• General management: avoid precipitating factors, use emollients to reduce sclaes
• Topical therapies (mild-mod psoriasis): vitamin D analogues –> topcal dithranol –> topical tacrolimus (adults)

Extensive disease:

• Phototherapy (UVB and photochemoterapy ie psoralen + UVA)
• Oral therapies: methotrexade, retinoids, ciclosprin, etc

Question 13

Name some exacerbating factors for psoriasis

Answer 13

Question 14

What is acne vulgaris? Name some features

Answer 14

Disease of the pilosabaceous unit

• Comedones (open or closed)
• Papules and pustules
• Nodules and cysts
• Ice pick scars hypertrophic scars

Question 15

What is the management for acne vulgaris?

Answer 15

-General measures

Mild acne

• Single topical therapy: topical retinoid or benzyl peroxide
• if unsuccessful: combination benzoyl peroxide and topical antibiotics, topical retinoids

Moderate-severe acne
-Oral antibiotics: tetracyclines (avoid in pregnant/breastfeeding ladies)
-COCP in women - Dianette has anti-androgenic properties
-Oral retinoids: isotretinoin (must only be prescribed by specialist
*Pregnancy is a total CI for any form of retinoid
**There is no dietary modification which has been found to help with acne