Eczema (syn. dermatitis)

Latest update 24/03/2010

This chapter is set out as follows:

• Atopic eczema (including bandaging, food allergy, eczema herpeticum)
• Atopic scalp eczema
• Discoid (nummular) eczema
• Gravitational eczema
• Asteatotic eczema
• Hand dermatitis
• Contact allergic dermatitis (including latex and rubber allergy)
• Napkin dermatitis

Atopic eczema

Definition

An inflammatory skin reaction characterized histologically by spongiosis with varying degrees of acanthosis, and a superficial perivascular lymphohistiocytic infiltrate. The clinical features may include itching, redness, scaling and clustered papulovesicles. The condition may be induced by a wide range of external and internal factors acting singly or in combination. The terms eczema and dermatitis are nowadays generally regarded as synonymous

Incidence

• Eczema affects 1 in 5 children
• Most children out grow atopic eczema as they get older. In approximatley 65 % of children the eczema has gone by the time they are seven years of age and in approximately 74% of children the eczema will have disappeared by 16 years of age. It isn't possible to tell whether children will or will not out grow their eczema, although generally speaking those with more severe eczema are less likely to outgrow it
• Although eczema presents most frequently in childhood it can present at any age, and 1/3 of all new cases arise in adults

Aetiology

• Both genetic and environmental factors play a role
• Atopic dermatitis usually occurs in people who have an 'atopic tendency'. This means they may develop any or all of three closely linked conditions; atopic dermatitis, asthma and hay fever (allergic rhinitis). Often these conditions run within families with a parent, child or sibling also affected
• Current evidence points to mutations in the filaggrin gene being likely to underlie almost half the cases of atopic eczema. Filaggrin is critical to the conversion of keratinocytes to the protein/lipid squames that compose the stratum corneum, the outermost barrier layer of the skin. A primary defect in the skin barrier function therefore appears to underlie atopic eczema, and immunological changes are probably secondary to enhanced antigen penetration through a deficient epidermal barrier. The relevance of this finding is that it reinforces the importance of the regular use of emollients to help manage eczema

Triggers

Spontaneous flare-ups are often the result of triggers. Triggers are not the same for everyone, but there are a number of common ones:

• Soap and detergents
• Overheating / rough clothing
• Skin infection
• Animal dander (fur, hair) and saliva - if resulting from a pet symptoms often improve when patients spend time in a different environment for a few days
• Aeroallergens (pollens) - reactions to airborne allergens may cause a worsening of symptoms (often facial) over spring / summer in those sensitised. This is most commonly seen in older children and adults
• Food – primarily in infants and young children (see later under management)
• House-dust mites and their droppings - sensitised patients may notice a worsening of facial eczema when they wake up
• Stress

Key diagnostic features

• Personal or family history of atopy
• Itch
• Many patients have more troublesome symptoms in winter as a result of central heating drying the skin out
• Distribution:
  • Face in infants
  • Flexures
  • Can become widespread
• Morphology:
  • Erythematous patches that are often poorly defined
  • Lichenification
• Other affected sites:
  • Scalp may be generally erythematous with fine scale

	Figure 1 - Atopic eczema involving the flexures
	Figure 2 – Atopic eczema Ill-defined erythema   (copied with kind permission of dermatoweb)
	Figure 3 – Infected eczema right cheek
	Figure 4 - Atopic eczema Ill-defined erythema
	Figure 5 - Atopic eczema in an adult
	Figure 6 - Atopic eczema
	Figure 7 – Atopic eczema in darker skin
	Figure 8 – Same patient as above In darker skin prominent follicular involvement is a frequent finding in patients with atopic eczema
	Figure 9 – Steroid atrophy Resulted from daily applications of Eumovate

Management of atopic eczema

General points - as with other chronic skin conditions:

• Time is needed by the GP / practice nurse to discuss the condition, advise on how best to use emollients and to provide an individual management plan
• Provide patient information leaflets and/or direct to appropriate websites
• Advise on a pre-payment exemption certificate where appropriate
• At each step it is essential to ensure patient compliance and to make sure that copious amounts of emollients are being used

Step I - Initial consultation

For patients presenting with relatively mild eczema – go to Step II

For patients presenting with a flare – in bot h children and adu lts it is more effective and safer to 'hit hard' using more potent treatments for a few days than it is to use less potent treatments for longer periods of time:

• Use a moderate/potent topical steroid e.g. Elocon ® (Mometasone) cream OD u ntil thing settle down. Patients may also need an appropriate systemic antibiotic i.e. flucloxacillin (erythromycin if allergic) for one week
• If the eczema is relatively localised consider using Fucibet ® cream instead, without a systemic antibiotic
• For marked sleep disturbance consider a sedating anti-histamine at night e.g. adults – Atarax ® (Hydroxyzine) 25-50 mg, and children – Piriton ® (Promethazine) 5-15 mg. Their is almost no role for non-sedating antihistamines in the management of eczema, the only exception is patients needing treatment for co-existent hay fever
• Take a skin swab if not settling
• Review the patient in 1-2 weeks to discuss long-term management

Step II- Long-term managament

i) Emollients - should be the mainstay of therapy. Good evid ence shows that the more emollients are used, the less topical steroids are needed. Complianc e is essential and so always review patients to check they are happy with what has been prescribed – it may be necessary to try a range of emollients before the p atient settles on the best combination

Moisturisers

• Most patients prefers creams and gels. The most important factor is to find one that the patient likes and is happy to use
• Ointments tend to be less well tolerated by patients, but they are less likely to cause contact allergic dermatitis as they do not contain preservatives (this is for both emollients and topical steroids)
• Encourage appropriate usage by prescribing generous amounts, e.g. 500 g. of moisturisers to use regularly (often QDS)
• As with other topical treatments, moisturisers should be gently rubbed into the skin until they are no longer visible. They should be applied downward in the direction of the hairs to lessen the risk of folliculitis
• Warn that they may sting for the first couple of days before soothing the skin
• Ointments come in tubs and so can easily become cross infected with bacteria from the skin – patients must not place hands into tubs but instead use a utensil to scoop out the ointment
• Patients can be shown how to apply moisturisers properly at the surgery or they can obtain a DVD

Bath / shower gels

• Does the patient bath or shower more?
• Patients getting frequent flares may benefit from emollients with an anti-septic property e.g. Dermol ® 600 Bath Emollient or 200 Shower Emollient, Emulsiderm ® Liquid Emulsion or Oilatum ® Plus Bath Additive
• Patients complaining of very itchy skin may benefit from an emollient with an anti-pruritic property such as Balneum-plus ® Bath Oil
• Patients must pat themselves dry after bathing
• Careful consideration must be given as to whether or not to use these products in patients with poor mobility due to the increased risk of slipping in the bath or shower

Soap substitutes

• Although patients like soaps as they make a lather, they damage the skin barrier and so should be avoided where possible
• Although specific soap substitutes can be prescribed it is probably more cost effective to use one of the prescribed moisturisers as a wash – ointments in particular can provide an effective wash

ii) Topical steroids for long-term control of inflammation - use the lowest appropriate potency and only apply thinly to inflamed skin. Allow to dry into skin for 20 minutes before applying moistuiser. Avoid using combined steroid/antibiotic preparations on a regular basis (e.g. Fucibet and Fucidin-H cream) as it will increase the risk of antibiotic resistance. Strength of steroid to be determined by the age of patient, site and severity:

• Child face: mild potency e.g. 1% Hydrocortisone
• Child trunk and limbs: moderate potency e.g. Eumovate ® (Clobetasone butyrate 0.05%) or Betnovate-RD ® (Betamethosone valerate 0.025%)
• Adult face: mild or moderate potency e.g. Eumovate
• Adult trunk and limbs: potent e.g. Betnovate ® (Betamethasone valerate 0.1%), Elocon ® (Mometasone)
• Palms and soles: potent or very potent e.g. Dermovate ® (Clobetasol propionate 0.05%)

If used approrpriately it is uncommon to develop steroid atrophy, however extra care needs to be taken in the following sites:

• Around the eyes: unless used very infrequently topical steroid preparations should be avoided due to the risks of glaucoma
• The face - the regular use of topical steroids should be avoided
• Lower legs in olde r patients / others at risk of leg ulcers - as above

Where there are concerns that the patient may be using too much topical steroid, especially on the sites referred to above, or there are signs of atroph y go to step IV

Step III - Treatment of flare-ups

• For infrequent flares (every 4-8 weeks) manage as in step I
• For more frequent flares
  • Check compliance
  • Swab the skin - for frequent infections it is useful to take nasal swabs and if positive for S.Aureus treat with nasal Bactroban ® cream BD for one week
  • Consider the Elocon weekend regime for both children and adults - Elocon should be applied thinly to inflamed areas OD for two weeks and then alternate days for a further two weeks. Once the eczema is under control use Elocon on two consecutive days (e.g. Saturday and Sunday) of each week to the areas that tend to flare. The treatment must be applied even if the skin in not inflamed – the aim is to reduce the frequency of flares
  • An alternative to the Elocon weekend regime is to use Protopic ® ointment (an immunomodulator - see below) - as above the eczema first needs to be brought under control by more frequent use of the proptopic and then reduce down to twice a week

Patients not responding to the above - consider the possibility of a contact allergic dermatitis (see later). Go to Step IV/V

Step IV - Treatment with immunomodulators

• The topical immunomodulators, Protopic ® (tacrolimus) and Elidel ® (pimecrolimus) are calcineurin inhibitors
• Their main benefit is that they are not steroid based and so do not cause skin atrophy
• Formulations
  • Protopic 0.03% ointment and Elidel cream are licensed for ages 2 years and above
  • Protopic 0.1% ointment is licensed for ages 16 yeas and above
• Local adverse effects include stinging, burning, itch, irritation and slight photosensitivity - appropriate sun protection is recommended. Adverse effects are more common with Protopic but in many patients are transient. Immunomodulators should be temporarily discontinued when the skin is infected
• When to consider immunomodulators:
  • Eczema involving the eyelids and peri-orbital skin
  • Patients regularly using topical steroids on the face
  • Patients regularly using topical steroids on the lower legs in elderly patients and others at risk of leg ulcers
  • Any signs of skin atrophy
  • When eczema is widely distrubuted AND patients are using too much topical steroids - see step III
• In milder cases use Elidel cream, although if this is ineffective or in the first instance the eczema is of a greater severity consider Protopic ointment. Protopic can also be used on a twice weekly regime, as in step III to reduce the frequency of flares. Proptopic should be allowed to dry into the skin for 60 minutes before applying moisturisers, whereas with Elidel patients only need wait 20 minutes
• While short-term data has showed no serious adverse effects, the possible long-term adverse effects of immunomodulators are not yet known - however the risks are likely to be minimal especially when the treatments are used in the ways described above. For patients using larger quantites (i.e. more frequent applications to larger areas), especially of Protopic, referral to a specialist is advisable

Step V - Referral to a specialist

The following patients should be referred to a specialist:

• Diagnostic uncertainty
• Severe eczema
• Moderate-severe eczema only partially responding to steps I-IV
• Steroid atrophy or concerns regarding the amount of topical steroids / Immunomodulators being used
• Possible cases of contact allergic dermatitis – see later

Bandages and dressings

• Some patients find dry bandages (e.g. Clinifast ® or Tubifast ® bandages) or medicated dressings (e.g. Viscopaste) helpful. They can be used on top of emolllients and topical corticosteroids for 7-14 days during flare-ups, or for longer periods on chronic lichenified eczema. There is no good evidence to support the use of wet wraps
• Do not use - on infected eczema

Food allergy and the skin

Presentation:
Along with other allergens, food can be responsible for some type I and type IV reactions

• Type I reactions
  • Contact urticria (e.g. perioral / cheeks)
  • Acute/intermittant urticaria
  • Acute flare-ups of chidlhood eczema
• Type IV reactions - these result in less clinically obvious flares of childhood eczema

Types of food causing type I reactions:

• Milk, egg white and peanuts account for 75% of reactions
• Treenuts, fish (including shellfish), soya and wheat account for most of the rest
• Citrus fruit (e.g. oranges, lemons, grapefruit and tangerines) and tomatoes can also cause type I reactions

Investigations and general management

• In the majority of cases where the offending food is obvious, tests are not needed and the diagnosis can be confirmed by dietary exclusion for 4-6 weeks
• Where symptoms are troublesome and there is some uncertainty as to whether or not food could be implicated then it may be helpful to do blood IgE levels and RAST tests for those foods most commonly associated with type I reactiosn (as above) and/or any other suspected food
• RAST tests have their limitations - a positive RAST test does NOT confirm that any given food is responsible for the rash. If a RAST test is positive the food should be excluded for 4-6 weeks to see if thier is a link. Also RAST tests will only detect type I reactions and not type IV reactions, which can sometimes be responsible for milk allergy
• The following patients should be referred to an immunologist:
  • Certain food allergies – patients with moderate/severe reactions to eggs. Patients with nut allergies often have multiple allergies and may require further investigations
  • Patients with life-threatening symptoms such as severe angioedema (e.g. with swelling of the mouth or throat) and anaphylaxis sometimes require further investigations, and may benefit from advice on how to manage symptoms including the proper use epipens
• For further information on eczema see below  

Eczema

• Food allergy has a role to play in 7% of patients with atopic eczema
• It predominantly affects infants and young children
• Most children with mild-moderate eczema that responds well to treatment do NOT have a food allergy - in such patients, and in the absence of any close temporal link between a particular food causing a flare of eczema investigations and dietary restrictions are not generally recommended
• Milk allergy – can be difficult to diagnose as it can cause a type I or type IV reaction and so food specific blood IgE or RAST tests for milk are not always helpful as they are only relevant for type I reactions. Milk allergy should be considered in young patients (primarily under the age of 3) with:
  • Type I reactions (e.g. urticaria, wheeze, reflux, vomiting) after ingestion of milk
  • Multisystem involvement such as skin, respiratory and gastrointestinal (diarrhoea, vomiting, failure to thrive)
  • Moderate to severe eczema responding poorly to topical treatments
• Managing possible cows milk allergy
  • Exclude cows milk for 6-8 weeks - in breast feed infants the mother needs to avoid all sources of cows milk. If bottle fed replace with protein hydrolysate milks (e.g. Prejomin ®), or amino acid derived formulae (e.g. Neocate ®). Avoid Soya due to high antigenic cross over
  • If a significant improvement is noted remain off cows milk and refer to a dietician
  • Milk allergy normally resolves by 2-3 years of age 

Eczema herpeticum

• Atopic patients develop more extensive eruptions with herpes simplex (eczema herpeticum) and varicella-zoster. Consider infection with herpes simplex if:
  • Clustered vesicles / punched-out monomorphic erosions which may coalesce
  • Areas of rapidly worsening, painful eczema
  • Fever, lethargy or distress
• Treat suspected eczema herpeticum immediately with systemic aciclovir and discuss the same day with the on-call dermatologist
• If eczema herpeticum involves the skin around the eyes, refer for same-day ophthalmological advice

	Figure 10 – Eczema herpeticum
	Figure 11 – Eczema herpeticum (copied with kind permission of Dermatoweb)

Atopic scalp eczema

• Clinical findings - general erythema and fine scaling (as opposed to psoriasis where there are areas of normal skin in between the psoriasis, and hairline involvement)
• Beware of nits presenting as scalp eczema
• Treatment
  • If a lot of scale is present remove scale with e.g. Sebco ® ointment, applied for 2-4 hours before shampooing, twice weekly
  • Mild tar-based shampoo
  • Water based topical steroid scalp application, e.g. Betacap ® OD-BD to eczematous areas until settles (alcohol based lotions will sting)
  • In young children (e.g. 18 months and under) it is often better to use an emollient bath oil to wash the hair rather than using a specific scalp treatment

Discoid (nummular) eczema

• History – very itchy, can be associated with excessive bathing or swimming
• Age – more common in adults than children
• Distribution – can occur anywhere although the limbs predominate
• Morphology - discrete round / oval patches. Differ from psoriasis in that lesions tend to be a lighter red, the border fades gradually at the periphery and they may have an exudate / crust as opposed to scale
• Management:
  • Provide a patient information leaflet
  • Generally manage as per atopic eczema
  • Lesions tend to respond well to a short course of a potent topical steroid such as Fucibet ® cream

	Figure 12 – Discoid eczema  (copied with kind permission of dermatoweb)
	Figure 13 – Psoriasis Lesions tends to be duller with a more abrupt edge and scale

Gravitational eczema (syn. varicose eczema or stasis dermatitis)

• A common problem associated with venous incompetence. Varicose veins may not be evident
• Distribution - localised or diffuse involvement of the gaiter area. Often bilateral
• Appearance – erythema, may be dry and scaly or weepy
• Differential diagnosis – gravitational eczema is often misdiagnosed as cellulitis. Cellulitis is nearly always unilateral, tender and has a well demarcated edge

Management

• Provide a patient information leaflet
• Use copious emollients (as in atopic eczema)
• If the skin appears infected (see figure 13) either swab skin or treat empirically with appropriate antibiotic (e.g. flucloxacillin + penicillin V or erythromycin if penicillin allergy for 10-14 days)
• Topical steroids may be needed intermittently – use minimum dose due to increased risk of skin atrophy. If needed regularly consider replacing with a topical immunnomodulator such as Protopic ® ointment
• For troublesome symptoms consider the possibility of a contact allergic dermatitis to one of the treatments being used – this is more likely if there is eczematous spread to distant sites (see later under contact dermatitis)
• For persistent symptoms consider the use of a potential topical steroid e.g. Betnovate-C ® ointment applied to eczematous areas of skin, and an ointment such as Epaderm / Hydromol to unaffected areas of the lower legs, under occlusion. One of the most useful ways of occluding the skin is to use Viscopaste ® bandages (place either a Coban ® bandage or plain cotton bandage on top) - practice / district nurses should be familiar with this technique so that they can demonstrate it to the patient. Correct application of bandages can be shown by clicking here. Bandages should be changed once or twice a week until things settle
• In the long-term promote treatment of underlying venous conditions by the use of compression hosiery (normally prescribed from the pharmacy as 'made to measure' Class II below knee, open toe stockings – it is worth asking the nurses to check the ankle-brachial pressure index to make sure there is no significant arterial insufficiency that would exclude their use)

	Figure 14 – Gravitational eczema
	Figure 17 – Gravitational eczema – secondarily infected   (copied with kind permission of dermatoweb)

Asteatotic eczema (syn. xerotic eczema, eczema craquele)

• A very dry eczema that is most commonly seen in the winter
• Age – predominantly in older patients
• Distribution – lower legs but can be widespread
• Appearance similar to that of 'crazy paving'
• Management – copious amounts of ointment based emollients is the main stay of treatment

	Fig. 16 - Asteatotic eczema
	Fig. 17 - Asteatotic eczema that has become impetiginised

Hand dermatitis

Aetiology  

• Often results from a combination of causes including genetic or 'constitutional' factors (their may be a personal or family history of eczema or other atopic disorders), contact with irritants (contact irritant dermatitis) or allergy (contact allergic dermatitis – see section below on contact allergic dermatitis)
• A good history is needed to identify relevant occupational factors and hobbies

Presentation

• Dry and scaling (if features asymmetrical it is important to look for tinea - skin scrapings should be sent for mycology)
• Wet and weeping (with or without vesicles / blisters)
• Pompholyx – a specific type of eczema that usually presents periodically with intensely itchy vesicles that predominate on the palms and sides of fingers. On occasions large blisters may develop
• Hyperkeratotic – thick areas of scale on the palms and soles. Can be very difficult to distinguish from psoriasis although the latter may be better demarcated

Management of hand dermatitis

• All patients must be given a patient information leaflet on hand dermatitis informing them of good hand care
• Gloves
  • Hands should be protected when doing house / occupational work
  • Patients can use either cotton gloves (cotton gloves should be washed inside pillow cases otherwise they tend to fall apart in the washing machine), vinyl gloves or rubber gloves (the latter two are both suitable for 'wet' work)
  • Cotton lined rubber gloves should be used for patients allergic to certain allergens such as acrylates and epoxy resins, which can penetrate rubber and vinyl gloves
  • See below if latex / rubber allergy is suspected
• Eliminate any obvious cause – perform swabs for bacteriology and treat if positive. Take skin scraping for mycology if appropriate
• Aspirate any large bullae
• For weeping skin / large bullae: soak hands in 1:80000 potassium permanganate solution (one Permitab ® in 4 litres warm water) x 2-4/day for 10-15 minutes . Warn patient to apply vaseline to avoid staining fingernails brown. Supply non-adhesive dressings and light bandages
• Emollients - hand wash e.g. Aqueous cream, E45 ® Emollient Wash Cream. Moisturisers must be applied frequently
• Potent / super potent topical steroids are often needed to treat hand dermatitis e.g. Betnovate-C ® cream or Dermovate cream. If the hands are not weeping the effects of treatment can be enhanced by way of night time occlusion using either cotton gloves or cling film wrapped around troublesome areas. An alternative is Haelan ® tape
• Oral steroids may be needed if symptoms severe - cover with an antibitoic if infected
• Hyperkeratotic eczema - may affect the palms and soles. Use Diprosalic ® ointment BD. If there is a large amount of scale consider using 5 % salicylic acid ointment in yellow soft paraffin BD (needs to be made up and can be expensive, considerable variation in cost across different community pharmacies). As the scale diminishes change over to Diprosalic ointment. Any of these treatments can be applied under occlusion (e.g. clingfilm or cotton gloves) overnight

Who to refer

• Troublesome symptoms not responding to the treatments referred to above
• If contact allergic dermatitis (CAD) is suspected e.g. if occupation or hobbies appear be relevant. Don't over look the possibility of CAD in children - those with predominant and persistant hand dermatitis could have a CAD to certain materials found in toys e.g. cobalt
• It can be difficult to differentiate contact allergic dermatitis from other types of hand dermatitis - discuss referral pathways with local dermatology departments as some may wish to have referrals for hand dermatitis directed to dermatologists performing patch test clinics to rule out CAD
• Difficult cases of hyperkeratotic hand / foot eczema for consideration of systemic treatments such as Neotigason ® (Acitretin) and Toctino ® (Alitretinoin), which can lead to substantial improvements (see below)

• Is licensed for patients aged 18 and over with difficult hand eczema, which has failed to respond to appropriate topical steroids. Although it can be used for any type of hand dermatitis it is more effective for hyperkeratotic eczema and less so for vesicular eczema
• Is teratogenic so as with isotretinoin all woman of childbearing age need to be on a pregnancy prevention program. It should be prescribed in the same context as with isotretinoin and by dermatologists, or physicians with experience in the use of systemic retinoids who have full understanding of the risks of systemic retinoid therapy and monitoring requirments - this could include an experienced GPwSI working in an integrated fashion with a consutlant dermatologist. For more information please refer to the section on isotretinoin prescribing in the acne chapter 
• The usual dose is 30 mg OD
• Adverse effects: raised lipids (cholesterol and triglycerides) – check fasting lipids before treatment started and monitor. No need to monitor LFT. Headache – improves with time and so can support with analgesia, or change to the lower does of 10mg OD. Other – erythema, flushing, dry skin and eyes, reduced TSH + T4 levels (no need to monitor if on intermittant treatment), raised CPK (uncommon, monitoring not needed but warn patients to report muscle weakness /tenderness)
• Treatment course: 48% clear at 3-6 months, stop treatment once clear. 2/3 of patients remain clear six months after stopping treatment.  Can have further courses if needed. If no significant response at 3 months (18% of patients) stop treatment as continuing on unlikely to be of benefit  

	Figure 18 – Hand dermatitis
	Figure 19 – Hand dermatitis
	Figure 20 – Hand dermatitis Erythema, scaling and fissuring
	Figure 21 – Pompholyx
	Figure 22 – Pompholyx This patient had developed large bullae, which they burst themselves
	Figure 23 – Hyperkeratotic hand dermatitis
	Figure 24 – Tinea Patients with fine scaling in the creases (especially if unilateral) always need skin scrapings for mycology

Contact allergic dermatitis (CAD) / Latex and rubber Allergy

It is not always easy to diagnose contact allergic dermatitis on clinical grounds alone. Although the history may give clues to the cause some cases of allergy develop a considerable time after first contacting the offending substance

Referral to a dermatologist with an interest in contact dermatitis should be considered for the following:

• Cases of troublesome hand and foot eczema, unless obviously part of a widespread constitutional eczema, that respond inadequately to treatment or where occupational factors are likely to be relevant
• Face or eyelid eczema unless obviously part of a widespread atopic eczema or seborrhoeic dermatitis. In patients whose symptoms predominate in spring / summer consider an airboune contact dermatitis (see figure 34)
• Troublesome pruritus ani – can be related to medications used either to treat haemorroids or the skin
• Resistant cases of otitis externa
• Possible allergy to topical treatments - medicaments account for upto 30% of all cases of contact allergy. It is important to be alert to the possibility especially if there is a history of an eczematous eruption at the site of application or where eczema suddenly deteriorates without any other clear cause. The topical antibiotic Neomycin (found in Betnovate-N amongst other things) is one of the main offenders. Hydrocortisone is the topical steroid most commonly associated with CAD and should be avoid at sensitive sites such as around leg ulcers. Creams are more likely to cause CAD then ointments
• Children - it is important not to overlook the possibilty of CAD in children, for example:
  • Predominant and persistant hand dermatitis could represent an allergy to cobalt found in certain toys, or to parabens in play-doh
  • Eczematous changes on the lips could represent an allergy to palladium found in some orthodontic devices

Latex and rubber allergy

Contact urticaria

• Over 90% of natural rubber comes from the latex, or milky sap, of the rubber tree - Hevea brasiliensis
• Latex is found in gloves, catheters and numerous other medical and dental devices. It is also found in a wide range of other products including condoms, balloons and a number of adhesives
• Allergy to latex normally causes a contact urticaria, which usually presents with itching and swelling of the skin at the site of contact with latex. The symptoms usually start within a few minutes of contact, although they can be delayed for several hours
• More severe symptoms include asthmatic reactions (to powdered latex gloves) and anaphylaxis
• Patients with suspected latex allergy should be referred to a dermatologist for confirmation of the diagnosis (the history and examination may suffice - if not skin prick tests may be needed) and management advice

Contact allergic dermatitis

• A contact allergic dermatitis normally occurs in response to the chemicals used to make the latex product especially 'rubber accelerators' e.g. thiuram and carbamates
• Symptoms are not immediate and cause a type IV allergic reaction with itch and erythema. Occasionally the reaction can be more acute with swelling, blisters and exudate
• Patients should be referred to a dermatologist for patch testing

	Figure 25 – Contact allergic dermatitis (CAD) to chromate in cement (copied with kind permission of dermatoweb)
	Figure 26 – CAD to Balsum of Peru (used in cosmetics) (copied with kind permission of dermatoweb)
	Figure 27 – CAD to paraphenylenediamine (PPD) in hair dye Marked facial oedema
	Figure 28 – CAD to nail polish
	Figure 29 – CAD to nickel earings
	Figure 30 – CAD to the backs of glasses
	Figure 31 – CAD to rubber in elastic belt
	Figure 32 – CAD to thiuram in rubber gloves
	Figure 33 – Latex allergy (contact urticaria) Erythema and oedema with cut off at wrists
	Figure 34 – CAD to topical antibotic / steroid preparation in gravitational eczema
	Figure 35 – CAD to eye preparation
	Figure 36 – CAD to anti-herpetic cream
	Figure 37 - Airborne contact dermatitis to sesquiterpene lactones in plants Sesquiterpene lactones are allergens found in the compositae species of plants such as dandelions and chrysanthemums. They are not photosenitising agents but instead cause an allergic contact dermatitis. Photo-protected areas of the face and neck are not spared. Symptoms arise in the spring / summer Airborne contact dermatitis presents in a similar fashion to photodermatoses, however close examination should reveal subtle differences in that with photodermatoses there is often sparing of the photo-protected areas (i.e. infra-orbital ridges, philtrum, upper lip and submental areas) For more information refer to the chapter on photodermatoses

Napkin dermatits

• Usually caused by the contact irritant effects of the nappy contents – skin folds tend to have relative sparing (unless associated with a secondary infection such as candida)
• Prolonged wearing of wet or soiled nappies may indicate ammoniacal dermatitis, which causes erosions and ulceration. This is less common now that disposable nappies are widely used
• Infection with bacteria and candida is not uncommon, the latter causes satellite lesions and their is no sparing of the folds
• Others causes include underlying skin disorders such as:
  • atopic eczema
  • seborrhoeic dermatitis - presents in young infants with confluent erythema and scale. Other sites include the scalp, face, neck and axillae. Their is no sparing of the folds. Unlike with atopic eczema infants are comfortable and sleep is not affected. Seborrehoeic dermatitis is discussed elsewhere

Management

• Take swabs
• More frequent changes of nappies or even leaving the child out of nappies for short periods of time may be required
• Avoid soap. Use a soap substitute e.g. aqueous cream, Diprobase as a wash at every nappy change and when in the bath
• Apply a moisturiser to the skin before applying each nappy
• If the skin is very inflamed, an antifungal/hydrocortisone combination such as Daktacort ® cream BD in addition to the above steps, can be useful. Stronger topical steroids such as Trimovate ® cream are occasionally needed for a few days

	Figure 38 – Napkin dermatitis (contact irritant) Sparing of folds
	Figure 39 - Ammoniacal dermatitis Ulceration present
	Figure 40 – Candida Satellite lesions present, skin folds involved
	Figure 41 – Seborrhoeic dermatitis Confluent erythema with scale in a young infant, skin folds involved