Journal of Tissue Viability 1996 Vol 6 No 3 103

CONTACT DERMATITIS IN PATIENTS WITH CHRONIC LEG ULCERS SHEILA POWELL Consultant Dermatologist, Churchill Hospital, Oxford

SUMMARY In any situation where tissue viability is an issue, skin care is of vital importance. This needs to be considered when caring for any patient with a chronic wound, and is true for the heal­ing wound and the surrounding skin, but eczema/dermatitis is a particular complication in patients with chronic leg ulcers. A patient with a chronic leg ulcer may have an endogenous, stasis eczema, or an exogenous eczema - a contact dermatitis. An irritant contact dermatitis may be related to topical prepa­rations used or techniques of bandaging. An allergic contact dermatitis is a well recognised complication of management in patients with chronic leg ulcers. This should always be con­sidered and for investigation requires referral to a dermatolo­gist for patch testing. Eczema may be multifactorial and en­dogenous and exogenous factors may co-exist together. In management of patients with chronic leg ulcers the possibility of contact dermatitis should always be remembered. Prepara­tions which do not irritate and are unlikely to sensitise should be used and if eczema does occur, this should be treated and referral for patch testing considered.

INTRODUCTION In any situation where tissue viability is of concern, care of the skin surrounding the affected site and care of the healing skin in vitally important. The most obvious examples of this situa­tion are patients with chronic wounds eg chronic leg ulcers, pressure sores and healing bums. In these patients the sur­rounding skin may be affected by exudate from the primary lesion or by therapeutic agents used in management. In addi­tion, whenever the integrity of the skin is broken eg short term following surgery, but particularly in long term situations such as stoma care, and when fungating malignant lesions are present, the care of the surrounding skin is a priority. Good skin care is always important but where the function of the skin is in any way compromised eg the elderly, the bedridden or paralysed individual, the diabetic patient, then it becomes vital.

If, in these situations, the care of the surrounding skin is ne­glected or inappropriate then inflammation may result and this can clinically present as eczema/dermatitis. This paper will discuss the common causes of eczema, with particular refer­ence to contact dermatitis which is a well recognised compli­cation, increasing morbidity and delaying healing in patients with chronic leg ulcers.

ECZEMA /DERMATITIS Eczema and dermatitis are words used to describe the same clinical condition. Clinically this presents as an itchy, ery­thematous, often weeping, often dry and scaly eruption. Ec­zema may be endogenous or constitutional in aetiology or may be due to exogenous or external factors.

ENDOGENOUS ECZEMA Common clinical conditions are:

* atopic eczema,

discoid eczema, * seborrhoeic eczema, *

* pompholyx,

stasis eczema, * asteototic eczema. *

Chronic eczema due to venous statis is the most common type to affect the lower leg. Atopic, discoid and asteototic eczemas may also affect this area but usually with eczema elsewhere.

EXOGENOUS ECZEMA Exogenous eczema is also known as contact dermatitis. There are two types: an irritant contact dermatitis and an allergic contact dermatitis.

Eczema is common in patients with chronic leg ulcers. The cause may be multifactorial with endogenous (stasis) and ex­ogenous (irritant and/or allergic) factors playing a part but of these a contact dermatitis should always be considered. Fail­ure to recognise the presence of eczema around an ulcer will lead to increased morbidity from the ulcer and the possibility of a delay in healing.

IRRITANT CONTACT DERMATITIS IN PATIENTS WITH CHRONIC LEG ULCERS This will result either from chemical irritation of the skin, acute or chronic, or from mechanical factors, eg bandaging1

• These may occur together and the insults to the skin are often repeti­tive. Whether or not an irritant contact dermatitis will occur depends on the degree to which the skin is irritated and also on the underlying skin type. Any patient with a constitutional tendency to develop eczema will be particularly susceptible to the action of irritants. ·

104 Journal of Tissue Viability 1996 Vol 6 No 3

Irritants can include:

exudate from wounds, * skin washes, *

* dressings used, * skin care preparations used around the

wound such as moisturisers, especially if perfumed.

ALLERGIC CONTACT DERMATITIS IN PATIENTS WITH CHRONIC LEG ULCERS Allergic contact dermatitis is well recognised in patients with chronic leg ulcers2-1• To develop this the patient must first be sensitised (through skin contact) with an allergen. Once sen­sitised, on subsequent exposure of the skin to that allergen, the area of skin exposed will develop eczema - a contact dermati­tis. In severe cases this can spread outside the exposed area and affect the whole leg or even become generalised. It may even be more severe at sites distal to the affected leg. This is an example of Type IV, cell mediated hypersensitivity.

Why patients with chronic leg ulcers are particularly at risk is not fully understood, but the chronic nature of many leg ulcers and the use of many different medicaments, many of which contain ingredients which may sensitise, often within occlu­sive bandages, are thought to be factors. An allergic contact dermatitis should be considered in any patient with a chronic leg ulcer when eczema develops around the ulcer (Fig 1).

Figure 1: An allergic contact dermatitis

bers on Scanpor tape (Fig 2) which are then applied to the patients back (Fig 3). They are left in position for two days, then removed and the first reading of results is undertaken.

Figure 2: Allergens in Finn chambers on Scanpor tape.

Figure 3: Finn chambers applied to a patient's back

Investigation to exclude an allergic contact dermatitis as a cause The back is re-examined after a further 2 days. A positive of eczema is by means of patch tests and requires referral to a patch test is an area of eczema occurring at the site of allergen dermatologist. There are various techniques used. Most com­ exposure (Fig 4). Patients are tested to the European standard monly, small amounts of allergens are placed in Finn cham- series of allergens and a 'leg ulcer' series of relevant allergens.

Journal of Tissue Viability 1996 Vol 6 No 3 105

Figure 4: Positive patch test Is this an endogenous eczema, probably statis, or are there ex­ternal factors and if so, is the picture one of an irritant or an allergic contact dermatitis?

In considering these various qiagnoses the previous history and management of the patient can give important clues. All stages of patient care should be considered eg:

a what is applied to the skin when dressings are removed eg skin cleansers?

b what preparations are being used as treatment i on the leg as a whole eg moisturisers?

topical steroids? ii to the ulcer itself eg medicaments?

dressings? c what bandaging technique is being used2

•

It may be evident from the story that the skin has been exposed to irritants or potential allergens. Any patient with persistent eczema around a leg ulcer should be referred for patch testing.

PATIENT MANAGEMENT Whilst awaiting this referral the eczema should be treated and A patient presents with a chronic leg ulcer and surrounding the ulcer managed with preparations which are unlikely to sen­eczema. The question then to be answered is:- sitise or irritate.

Table 1 Commonly reported allergens in patients with chronic ulcers

ALLERGEN SOURCE

Topical antibiotics Medicaments eg framycetin, neomycin, eg Sofra-tulle, cicatrin powder, gentamicin cream and ointment. gentamicin

Lanolin and derivatives Many creams, ointments, emollients and moisturisers eg wool alcohols, eg E45 cream, hydrous ointment, Oilatum emollient. Amerchol LlOl, Eucerin

Cetyl stearyl alcohol Present in many cream preparations eg Hioxyl, (cetyl alcohol, stearyl Flamazine, E45, aqueous cream and corticosteroid cream. alcohol) In some ointments eg emulsifying ointment, in some paste

bandages.

Colophony/rosin Sticking plaster, adhesive in some bandages and some Esters of rosin hydrocolloid dressinGS.

Rubber chemicals Bandages and tubigrip containing natural rubber. eg Thiuram mix, Carba Elastic stockings containing natural rubber. mix, Mercapto mix

Preservatives and biocides In many medicaments and some paste bandages. eg parabens, Phenosept, chlorexylenol, Chinoform

a. Balsam of Peru/fragrance mix Home care preparations b. Benzocaine a) with perfume b) with local anaesthetic action.

Tixocortol pivalate one. Marker of corticosteriod hypersensitivity particular to hydrocortisone.

106 Journal of Tissue Viability 1996 Vol 6 No 3

Treat the eczema with a low or moderately potent topical ster­oid. Choose an ointment as these usually have white soft par­affin as their based and this is unlikely to sensitise. For a mois­turiser/emollient which will neither sensitise nor irritate, choose the mixture of 50% white soft paraffin and 50% liquid paraf­fin. Under bandages (compressive if indicated), apply a cot­ton tubular bandage to the skin to avoid irritation from the bandage itself.

ALLERGENS OF RELEVANCE IN PATIENTS WITH CHRONIC LEG ULCERS Although these depend on preparations used in patient man­agement, there are well recognised allergens of relevance in patients with chronic leg ulcers. Such a list could never be complete and a detailed history of leg ulcer management is always important. The allergens listed below are those most commonly seen in our clinic in Oxford and those reported in the literature (see also Table 1).

* Antibiotics which have been prescribed for topical use. Most topical antibiotics have been reported as being allergens but the most common culprits are those of the aminoglycoside group - neomycin, framycetin and gentamicin. Bactiracin would also appear to sensitise when this is used extensively8•

* Lanolin which may be known as 'wool fat' or 'wool alcohol'. Lanolin may be present in topical medi­caments, moisturisers and emollients.

* Cetyl stearyl alcohols are the base of many cream preparations. These include topical steroid creams moisturising creams and are also present in some paste bandages.

* Colophony or rosin and derivatives of rosin eg es­ters, can be part of the adhesive in some bandages and dressings.

* Chemicals such as accelerators and antioxidants are used in the rubber industry and can therefore be present in natural rubber containing bandages.

* Preservatives present in skin care preparations and some paste bandages can sensitise. Preservatives ofthe parabens group eg methyl-4-hydroxybenzoate, are examples.

10* Topical steroids can themselves sensitise9• •

Hy drocortisone and hydrocortisone-17-butyrate are the most common culprits.

* Constituents of home care preparations eg perfume in moisturiser, benzocaine, a local anaesthetic, in preparations for relief of pain.

RELEVANCE OF PATCH TESTING Following patch testing, advice can be given on suitable dress­ings, skin care preparations and bandages for the patient. Sadly many skin care preparations are as yet unlabelled and the onus is on the health care professional, to be aware of patients' sen­sitivities, and to be vigilant and check with pharmaceutical companies, as to the constituents of their products, especially if new preparations are to be used. Similarly it is important to be aware that· patients acquire sensitivities from exposure to allergens and negative patch testing some months or even years ago does not mean that the patient will not subsequently de­velop a sensitivity. If the clinical picture indicates that it is necessary, repeat patch testing will be required.

CONCLUSION When eczema occurs as a complication of a chronic wound such as a leg ulcer the possibility that this could be a contact dermatitis should be considered. In management of such pa­tients it is important firstly to use preparations which are un­likely to irritate or to sensitise and secondly if eczema does occur to consider referral for patch testing to exclude an aller­gic contact dermatitis.

Address for correspondence Dr S Powell, Consultant Dermatologist, The Churchill Der­matology Department, Old Road, Headington, Oxford OX3 7LJ.

References 1. Powell SM, Cameron JC. Irritant contact dermatitis in

patients with chronic leg ulcers. 1996 (in press). 2. Haxthausen H. Generalised 'ids' ('autosensitisation')

in varicose eczemas. Acta Dermatologica Venereal­ogica (Stockholm) 1955; 35: 271-280.

3. Maiten KE, Kuiper JP, Vander Staak WMJM. Contact allergic investigations in 100 patients with ulcus cruris. Dermatologica 1973; 147: 241-254.

4. Paramothsy Y, Collins M, Smith AG. Contact dermati­tis in patients with leg ulcers. Contact Dermatitis 1988; 18: 30-36.

5. Kulozik M, Powell SM, Cherry G, Ryan TJ. Contact sensitivity in community-based leg ulcer patients. Clini­cal and Experimental Dermatology 1988; 13: 82-84.

6. Wilson CL, Cameron J, Powell SM, Cherry G, Ryan RJ. High incidence of contact dermatitis in leg ulcer patients - implications for management. Clinical and Experimental Dermatology 1991; 16: 250-253.

7. Cameron J, Powell SM. Contact dermatitis: its impor­tance in leg ulcer patients. Wound Management 1992; 2 (3): 12-13.

8. Zaki I, Shall L, Dalziel KL. Bacitracin: a significant sensitiser in leg ulcer patients? Contact Dermatitis 1994; 31: 92-94.

9. Burden AD, Beck MH. Contact hypersensitivity to topi­cal steroids. British Journal ofDermatology 1992; 127: 497-500.

10. Wilkinson SM, Cartwright PH, English JSC. Hydro­cortisone: an important cutaneous allergen. Lancet 1991; 337: 761-762.