Eczema

Learning objectives Recognise the features of an eczematous rash Develop a rational method for classifying eczema Name the main types of endogenous and exogenous eczema Know how to distinguish irritant contact from allergic contact dermatitis Describe the theory behind patch testing, its method and indications Recognise and describe the distribution and morphology of atopic, discoid, varicose, pompholytic and seborrhoeic eczema List the common exacerbating factors for atopic eczema Develop a management plan for a patient with moderately severe atopic eczema List the main side effects of topical steroids and the measures needed to safeguard against these

Eczema Features Itching Scaling Dryness Fissures Bleeding Weeping Lichenification

Types of Eczema Atopic Discoid Seborrhoeic Venous/Gravitational Irritant Contact Allergic Contact

Localised or generalised Elderly, eczema on the legs with varicose veins, mainly immobile? Gravitational Eczema Localised to Face and Scalp? <2 years on first presenation, history of asthma/hayfever? No Yes Generalised Localised Seborrhoeic eczema Mainly on the hands and working with harmful substances? Atopic Eczema No Yes Discoid Allergic Contact dermatitis Irritant contact dermatitis

Atopic eczema Eczema, asthma, hay fever Family history Normally first presentation <2 years old 50% remission by 2, 80% have remission by adolescence Infants less than one year old: Widely distributed eczema The cheeks of infants are often the first place to be affected Nappy area spared due to the moisture retention of nappies Children: Often affects the extensor aspects of joints, particularly the wrists, elbows, ankles and knees. It may also affect the genitals May develop nummular pattern- mistaken for ringworm

Discoid Eczema Nummular dermatitis May be associated with staph aureus Affects children and adults, males>females Men over 50, chronic alcohol abuse Mainly limbs and trunk, asymmetrical distribution Two types: Exudative acute discoid eczema: oozy papules, blisters and plaques Dry discoid eczema: subacute or chronic erythematous, dry plaques Tests: bacterial swabs for staph aureus- antibiotics Scrapings to rule out ring worm (tinea corporis)

Gravitational Eczema Elderly people with: History of deep venous thrombosis in affected limb History of cellulitis in affected limb Chronic swelling of lower leg, aggravated by hot weather and prolonged standing Varicose veins Venous leg ulcers Thought to be caused by fluid collecting in the tissues and activation of the innate immune response May be mistaken for cellulitis - Crusting or scaling is the most important sign in eczema and this is not seen in cellulitis, small blisters may also be seen

Seborrhoeic Infantile and adult forms Associated with Pityrosporum Spp- metabolites cause an inflammatory reaction Adult scalp, face (creases around the nose, behind ears, within eyebrows) and upper trunk Winter flares, improving in summer following sun exposure Blepharitis: scaly red eyelid margins Infantile: Cradle cap under the age of 3 months and usually resolves by 6–12 months of age may spread to affect armpit and groin folds  salmon-pink patches that may flake or peel not especially itchy- babies unperturbed by the rash even when generalised

Irritant Contact Causes: Friction Environmental factors such as cold Over-exposure to water Chemicals such as acids, alkalis, detergents and solvents Damage occurring faster than the skin can heal- repeated exposure 80% occupational hand dermatitis caused by irritants Less likely to spread to other areas Heals when irritant removed Patch test? Allergic and irritant can co-exist

Allergic contact Arises hours after contact Contact urticaria within minutes Reaction to a harmless substance Commonly: Fragrances Dyes Nickel Rubber Patch testing Avoidance of substance

MANAGEMENT Principles Reduction of exposure to trigger factors (where possible) Regular emollients to treat dry skin topical steroids IMPORTANT TO HAVE STEROID FREE DAYS Potency steroid Mild Hydrocortisone 1% moderate eumovate Potent Elocon, betnovate Very potent dermovate Steroid s/es – rare Striae, telangiectasia, glaucoma and cataracts. NOT SKIN THINNING The effects of topical steroids on various cells in the skin are: Anti-inflammatory Immunosuppressive Anti-proliferative Vasoconstrictive The potency of topical steroids depends on: The specific molecule Amount that reaches the target cell Absorption through the skin (0.25%–3%) Formulation use mild potency for the face and neck, except for short-term (3–5 days) use of moderate potency for severe flares

FINGER TIP UNIT (FTU) The amount of cream that should be used varies with the body part: One hand: apply 1 fingertip unit One arm: apply 3 fingertip units One foot: apply 2 fingertip units One leg: apply 6 fingertip units Face and neck: apply 2.5 fingertip units Trunk, front and back: 14 fingertip units Entire body: about 40 units Index finer – very end of finger to first crease. 0.5g approx. for one FTU

2nd line treatments Topical immunomodulatory Bandaging/wet wraps – for chronic linchenified areas Systemic treatments UV Oral prednisolone, cyclosporine, azathioprine Calcineurin inhibitors - Topical tacrolimus for mod-severe eczema in adults and children >2 years old Infected eczema – flucloxacillin 1st line (or erythromycin) Topical tacrolimus is recommended, within its licensed indications, as an option for the second-line treatment of moderate to severe atopic eczema in adults and children aged 2 years and older that has not been controlled by topical corticosteroids Pimecrolimus is recommended, within its licensed indications, as an option for the second-line treatment of moderate atopic eczema on the face and neck in children aged 2–16 years that has not been controlled by topical corticosteroids Localised medicated dressings or dry bandages can be used with emollients as a treatment for areas of chronic lichenified (localised skin thickening) atopic eczema in children. Flucloxacillin should be used as the first-line treatment for bacterial infections in children with atopic eczema for both Staphylococcus aureus and streptococcal infections. Erythromycin should be used in children who are allergic to flucloxacillin or in the case of flucloxacillin resistance. Clarithromycin should be used if erythromycin is not well tolerated. The benefits of wet wrapping include: Reduced itching and scratching Reduced redness and inflammation Skin rehydration Better skin healing process Reduced steroid usage once the condition is controlled Improved sleep

Which one of the following best describes the typical distribution of atopic eczema in a 10-month-old child? 1) nappy area and flexor surfaces of arms and legs 2) face and trunk 3) nappy area and trunk 4) flexor surfaces of arms and legs 5) scalp and arms 2)

2) 1) Tinea manuum 2) Irritant contact dermatitis A 19-year-old female who has just started work as a cleaner presents with a rash on her hands. On examination there is a generalised erythematous rash on the dorsum of both hands. There is no evidence of scaling or vesicles. What is the most likely diagnosis? 1) Tinea manuum 2) Irritant contact dermatitis 3) Allergic contact dermatitis 4) Ichthyosis vulgaris 5) Pustular psoriasis 2)