Dermatology

Question 1

Eczema

Answer 1

Ax: Itchy ill defined erythematous scaly patches on flexor surfaces. Can be atopic, exogenous
Tx: Atopic: Topical- emollients, tar, steroids, PUVA, Systemic: PO antihistamines, Abx for infections, immunosupressants (azothioprine)

Question 2

Psoriasis

Answer 2

Ax: Polygenic susceptibility. Arthropathy ax with HLA B27, Exacerbating factors- drugs, stress, infections, strep for guttate
Sx: Types: Stable chronic plaque, guttate, ertythrodermic and pustular
Salman coloured silver scaly lesions often involving scap, behind ear, extensor surfaces.
Can be plaques, coin shapped, teardrop, Koebner phenomenon
Nail changes: Pitting, oncholysis, nail dystrophy, subungal hyperkeratosis
Tx: Supportive- emollients
Topical: Tar, topical steroids, dithranol, UVB, PUVA
Systemic: PUVA, Methotrexate, ciclosporin, hydroxycarbmide, sulfasalazine

Question 3

Lichen planus

Answer 3

Ax: Pruritic eruption of violaceous, shiny, polygonal papules with Wickhams stria (white lines)
Mouth: Oral involement - white or grey streaks forming a linear/reticulular patern.
Nails: Oncholysis, ridging, scarring of bed
Tx: Usually self limiting and resolves within 8-12 months

Question 4

Pemphigus

Answer 4

Ax: Direct action of an antibody attack on intra-epidermal desmosomal structure
Sx: Bullous lesions/blisters which may be confined to mucous membranes but can occur on trunk, scalp and other parts of the body, blisters can rupture easily as they are intra-epithelial
Ix: Biops, immunology- intracellular IgG, C3
Tx: Local wet dressings, lotions
Systemic: High dose steroids, immunosupressants, IV fluids
Cx: Secondary infection, sepsis, loss of body fluids and electrolytes

Question 5

Pemphigoid

Answer 5

Ax: Autoimmune reaction against the basement menbrane. More common elderly
Sx: Initially patients develop erythematous and eczematous areas on the trunk and limb, which develop into tense blisters, can be pruritic
Ix: IgG, C3 at basement membrane biopsy
Tx: Steroids, azathioprine

Question 6

Acne vulgaris

Answer 6

Ax: Non inflammatory follicular papules. In severe cases inflammtory papules, pustules and nodules. Affects areas of skin with sebaceous follicles
Tx: Topical: retinoids, Abx
Systemic: Abx (Tetracyclines), OCP, Isotretinoin

Question 7

Pityriasis Rosea

Answer 7

Ax: Papular skin eruption begins as a herald patch (pink oval patch 3-6cm in diameter). Normally found in back before distributed in christmas tree pattern.
Tx: Self limiting. Topical steroids in severe cases

Question 8

Dermatitis herpetiformis

Answer 8

Ax: Associated with coeliac disease
Sx: Itchy small blisers on extensor surfaces, buttocks or face
Tx: Dapsone, gluten free diet

Question 9

Ertythema nodosum

Answer 9

Ax: Tender, erythematous nodules which resolve after 6wks, occur on shins. Cause Infection:Strep,TB
Sarcoidosis, IBD, Sulfonamides, OCP
Tx: Treat underlying cause

Question 10

Erythema multiforme

Answer 10

Ax: Systemic eruption of raised target lesions. May be associated with pyrexia. If ax with mucosal involvement known as SJS
Causes: Infection, lupus, drug (sulfonamides,Abx), malignancy,Pregnancy, premenstrual

Question 11

Pyoderma gangrenosum

Answer 11

Ax: IBD, Seroneg RA, Myeloma,
Sx: Painful rapidly growing ulcerated nodules
Tx: Oral steroids

Question 12

Acanthosis nigricans

Answer 12

Ax: Malignancy, acromegaly, dermatomyositis, scleroderma, wilsons
Sx: Lesions begin as hyperpigmented macules/papules and progress to velvety plaques with ax skin tags. Most commonly occur in axilla, groin and posterior neck
Ix: Treat malignancy, diabetes, insulin resistance.