Atopic Eczema (Atopic Dermatitis) in Adults

Essentials

• Chronic intrinsic skin disorder, the cornerstones of treatment being symptomatic treatment of exacerbations and maintenance therapy.
• Diagnosis is based on the clinical picture, course of disease and exclusion of other skin disorders.
• Unjustified assumption of association with allergies, food or skin infections should be avoided.

Epidemiology and aetiology

• Chronic itchy skin disorder that may occur at any age (late onset disorder) but often begins in childhood.
• Intrinsic multifactorial aetiology
• Susceptibility to the disease is genetic, and the disease often occurs in the immediate family, as well.
• Patients often have other atopic disorders, i.e. allergic rhinoconjunctivitis Allergic Rhinitis Conjunctivitis, food allergies Food Allergy in Adults, asthma Asthma: Symptoms and Diagnosis Long-Term Management of Asthma.
• One of the most common skin disorders; in Finland, as many as 20 to 30% of adults have had the condition at some point.
• The disease may negatively affect quality of life (e.g. through itching, cosmetic problems) and cause psychosocial suffering and functional problems.
• In most cases, the disease is mild and has a good prognosis.
• There are no known means of prevention.

Clinical picture

• The course of the disease is usually chronic. Exacerbations, which are hard to predict, are typical for the disease.
• Chronic, itchy eczema at typical sites (skin creases, the face, neck, eyelids). Lichenification due to chronic friction can often be seen.
• The clinical picture usually varies, and the disease may take many different forms.
  • Typical Besnier's prurigo (elbow or knee creases [pictures ], wrists [picture ], ankles, neck)
  • Face, upper torso and neck (head and neck type)
    • On the face, often particularly in the eyelid area and also around the mouth Facial Dermatoses
  • Nummular eczema Nummular Dermatitis; pictures
  • Atopic eczema of the lower trunk and thighs; pictures
  • Chronic hand eczema Hand Dermatitis; pictures
  • Finger tips and palms (dermatitis palmaris sicca; picture )
  • Feet (balls of the feet and undersurfaces of the toes; dermatitis plantaris sicca, juvenile plantar dermatosis, atopic winter foot, pictures )
  • Atopic eyelid eczema, blepharitis Benign Skin Problems of the Eyelids; pictures
  • Chronic eczema or itching of the scalp, so-called sensitive scalp
  • Chronic eczema in the genital area
  • Lip eczema (atopic cheilitis)
  • Erythema and maceration of the skin at the corners of the mouth (angular cheilitis or Perlèche)
  • In some patients a chronic vicious circle of itching and scratching causes findings consistent with neurodermatitis (e.g. on the ankles, neck, genital area).
  • Nodular prurigo may be the predominant clinical feature (prurigo form of atopic eczema).

Aggravating factors

• Issues to be examined:
  • physical factors (sweating, friction, in some patients hot environment, wet work, holiday trips)
  • use of ointments, hygiene and cosmetic products
  • pollen or other allergies, foodstuffs.
• An atopic tendency (IgE-mediated sensitization to pollen or animals, for instance) alone does not explain atopic eczema but may in some patients aggravate the clinical picture (exacerbation of atopic eczema during the pollen season or through animal contact, for instance, delayed immunological mechanisms).
• Effective treatment of the eczema may reduce the symptoms of allergic rhinitis or asthma.
• In adults, food allergy (IgE- or non-IgE-mediated) alone will not explain the eczema but may in rare cases aggravate it (delayed immunological mechanism, exacerbation of symptoms usually with delay).

Diagnosis

• Should be made clinically.
• The clinical picture varies depending on the patient's age.
• The more of the following criteria are met, the more probable the diagnosis is.
  • Itching (always present; if not, the diagnosis is unlikely)
  • Chronic and relapsing course of disease
  • Dry skin (particularly in the winter)
  • Onset at a young age, atopic eczema in childhood (infantile atopic dermatitis)
  • Atopic tendency (diagnosis of IgE-mediated sensitization)
  • Diagnosis of asthma or allergic rhinoconjunctivitis
• In many patients, only a few of these criteria are met.
• Differential diagnosis on clinical grounds
• Skin infections - secondary bacterial infection of eczema (impetiginization) Impetigo and other Pyoderma, herpes simplex (eczema herpeticum) Herpes Simplex Infection of the Skin, warts Warts (Verruca Vulgaris) or mollusca contagiosa Molluscum Contagiosum - may occur more easily in these patients.

Differential diagnosis

• Trunk and limbs
  • Nummular eczema (often on the back and legs, single itching and scaly patches of eczema) Nummular Dermatitis
  • Allergic contact eczema (may spread or be primarily extensive, usually patchy) Allergic Contact Dermatitis
  • Scabies (intimate and other contacts, burrows on the wrists, between fingers, on the feet, lesions in the genital area) Scabies
  • Irritant contact dermatitis (restricted to skin areas subject to irritation, such as the backs of the hands) Irritant Contact Dermatitis
  • Psoriasis (typical sites, sharply defined, thick scale, family history, nail lesions, scalp lesions) Psoriasis
  • Ringworm (scaly, ring-shaped patches with clear centres on the trunk, limbs, groin, buttocks) Dermatomycoses
  • T-cell lymphoma of the skin (clinically resembling eczema at first, resistant to treatment, usually in the elderly) Lymphomas
• Hands Hand Dermatitis
  • Irritant contact dermatitis
  • Allergic contact eczema
  • Intrinsic (non-allergic) chronic hand eczema
  • Psoriasis
• Scalp
  • Seborrhoeic eczema
  • Psoriasis
  • Ringworm
• Face Facial Dermatoses
• Genital area

Workup

• No specific laboratory or allergy test will show atopic eczema, and these are therefore rarely helpful.
• Total serum IgE levels may be elevated and/or eosinophilia may be seen in the complete blood count. Normal values do not exclude the disease.
• In some adult patients, atopic eczema is exacerbated by allergens. In most cases, the eczema develops by a cell-mediated delayed mechanism that does not show in tests for immediate allergy (skin prick or specific IgE antibody tests).
• In adults, the eczema is not usually directly associated with IgE-mediated allergy. In some patients, IgE-mediated allergy (e.g. to foodstuffs, animals, pollen) may exacerbate the atopic eczema either directly (exacerbation of atopic eczema triggered by protein contact dermatitis) or through a combined effect of delayed mechanisms (mixed form). In such cases, prick tests or measurement of specific IgE antibodies may be indicated. Nevertheless, sensitization should always be interpreted in relation to the symptoms.
• The diagnosis of atopic eczema aggravated by food allergy should be based on elimination-challenge testing, not allergy tests. The patient can perform the testing at home (unless foodstuffs have caused serious reactions).
  • The foodstuff should be eliminated for 2 weeks. If symptoms subside, it can be reintroduced, observing the occurrence of symptoms. The patient should be encouraged to evaluate the association between foodstuffs and atopic eczema critically and systematically. In many cases, the challenge test should be repeated. If a foodstuff is found to aggravate the eczema, the patient should be encouraged to repeat the challenge test from time to time because tolerance to foodstuffs may develop Food Allergy in Adults.
• Bacterial culture may be performed if a patient with evident skin infection (such as secondarily infected eczema or impetigo) is suspected of being resistant to antimicrobial drugs.
• Bacterial samples taken from an area with eczema nearly always grow Staphylococcus aureus; this represents colonization, not infection. The culture finding does not prove causality, and colonization can usually be eliminated by treating the eczema.
• As necessary, herpes samples are taken from the skin (especially if Eczema herpeticum is suspected), Herpes simplex type 1 and 2, DNA detection (PCR).
• Samples for microscopy and fungal culture are required if ringworm is suspected. It is important to obtain a representative sample by plucking hair or scraping a scaly spot.
• In extensive eczema unresponsive to appropriate treatment histological examination of a skin biopsy sample may be needed to exclude diseases such as T-cell lymphoma of the skin.

Treatment Interventions to Reduce Staphylococcus Aureus in the Management of Atopic Eczema

• Treatment is symptomatic and based on the treatment of exacerbations and prophylactic maintenance therapy.
• Response varies and the disease may be reactivated after several years of remission. Exacerbations are hard to predict and often occur without any cause.
• Symptoms can usually be kept under control by intermittent treatment with mid-potent to potent (Class II-III) topical glucocorticoids (e.g. in courses of 2 to 3 weeks).
• For the face, intermittent treatment with mild (Class I) topical glucocorticoids (e.g. in courses of 1 to 2 weeks) or calcineurin inhibitors as either intermittent or maintenance therapy (e.g. twice a week) are used Facial Dermatoses.
• In atopic lip inflammation, mild (Class I) topical glucocorticoids used periodically (e.g. in courses of 1-2 weeks) or calcineurin inhibitors used periodically or as maintenance therapy (e.g. twice per week) are usually effective. In some patients, food allergies make the lip inflammation worse.
• Non-medicated ointments will not cure the inflammation due to atopic eczema but in long-term use they may reduce exacerbations and the need for glucocorticoid ointments Emollients and Moisturisers for Eczema. In acute weeping eczema, moist dressings or compresses can be used in addition to glucocorticoid ointment.
• Reduction or avoidance of factors historically aggravating the skin disorder (irritants, detergents, allergies)
• The skin can be washed normally using mild skin washes. Soap or other detergents, or alternatively a non-medicated aqueous cream, can be used for washing.
• Non-medicated aqueous emollient cream rubbed onto the scalp every night and intermittent use of a glucocorticoid liniment in courses of 2 to 3 weeks are effective for the treatment of atopic eczema of the scalp.
• If the eczema cannot be controlled by intermittent use of glucocorticoid ointment and maintenance treatment with non-medicated ointment, topical calcineurin inhibitors (tacrolimus and pimecrolimus) can be used, first twice daily until the situation is under control, and subsequently twice a week as maintenance treatment, for example.
• Pre- or probiotics (e.g. products containing lactic acid bacteria), herbal medicinal products (e.g. evening primrose or omega oil), vitamins (e.g. high doses of vitamin D), trace elements (e.g. zinc) or the like have not been shown to be useful in the treatment of eczema Dietary Supplements for Established Atopic Eczema.

Other possible treatments

• Remember to make sure that the treatment is actually being used. Treatment fatigue, fear of adverse effects of topical glucocorticoids, etc. are common.
• Topical treatment should always be intensified in addition to using other forms of treating the eczema.
• Combination ointments containing an antiseptic/antimicrobial agent and glucocorticoid can also be tried.
• If the eczema is clinically secondarily infected (impetiginization), systemic antimicrobial treatment may be necessary, first-line drug being cephalexin 500 mg 3 times daily or flucloxacillin 750-1 000 mg 3 times daily; the treatment period is usually 7-10 days. The same antimicrobial drugs as for the treatment of impetigo can be used and in similar doses Impetigo and other Pyoderma.
• Oral glucocorticoids, such as prednisolone 0.5-0.25 mg/kg (40-20 mg) every morning for 1 to 2 weeks, can be considered for short-term treatment of severe exacerbations. As long-term results of systemic glucocorticoids are poor, such treatment should only be used in exceptional cases. Rebound eczema may occur after treatment.
• As non-sedating antihistamines in normal doses may help to treat itching in some patients, they may be used in addition to topical treatment; for example cetirizine 10 mg 1-2 tablets once or twice daily. The dose exceeds that recommended by the manufacturer and hence the prescription should be furnished with the locally relevant indication of exceptional dosage instructions. The dose is titrated according to the response.
• For symptomatic treatment of itching, a sedating antihistamine for the night can be tried, such as 25-50 mg of hydroxyzine. The sedative effect of the drug and potential interactions with other medicines should be kept in mind.

Specialist consultation

• Severe atopic eczema may require consultation of a dermatologist and, in some cases, hospital treatment on an outpatient clinic or on a ward.
• Treatment alternatives for extensive eczema include phototherapy (narrowband UVB or SUP) and, in extremely severe or treatment-resistant cases, under the supervision of a dermatologist, systemic drugs (such as methotrexate, cyclosporine A or dupilumab, tralokinumab, baricitinib, upadacitinib, abrocitinib).
• Epicutaneous tests should be performed if allergic contact dermatitis is suspected.

Pictures