Eczema – Diagnosis, Symptoms, and Treatment

What is Eczema?

Eczema (atopic dermatitis) is a skin condition characterized by chronic inflammation and itching (pruritus), most commonly involving the hands and face. Patients often develop redness, dryness, thickening, crusting, and oozing of the skin in the affected areas. The disease most often affects children but may also be seen in adults. Individuals often have a diagnosis of other conditions that result from allergies, such as asthma, dry eyes, and allergic rhinitis. The predilection for allergen-related conditions such as eczema, asthma, and allergic rhinitis is referred to as atopy.

Risk factors for the disease include a family history of atopy and certain genetic mutations that reduce the ability of the skin to act as a barrier against the environment.

What Causes Eczema?

Eczema is caused by multiple factors such as genetic mutations, skin barrier dysfunction, and abnormalities in immune function. It is still unclear whether skin inflammation is initiated by abnormalities in the skin barrier or whether it is due to an abnormal immune response.

Major risk factors include family history of atopy - this refers to the presence of eczema, asthma, and allergic rhinitis. About 70% of patients have family members affected with atopy. Genetic mutations such as loss-of-function of the filaggrin gene is also implicated in the pathogenesis of the disease. Individuals exposed to day care and pets early in life may have a lower risk of developing eczema.

How Common is Eczema?

Worldwide, the prevalence of atopic dermatitis in children is about 5%-20% in the United States, approximately 11% of children are affected by the disease. The annual prevalence in adults is estimated to be 10%-15%. The incidence of atopic dermatitis is rising and is greater in urban areas and developed countries. The condition is slightly more common in females compared to males. Up to 50% of individuals who acquire the disease during childhood continue to have symptoms into adulthood. Approximately 60% of cases occur in the first year of life and about 85% of cases happen by age 5.

Eczema is commonly evaluated in the primary care clinic. Severe or advanced cases may require referral to a dermatologist, especially if first-line treatment was unsuccessful.

Signs and Symptoms

Patients typically develop symptoms before age 5 with the most common presenting symptoms being dry and red skin that results in severe itching. There are many other symptoms and signs than can develop throughout life, the most common being:

• Dry skin 
• Severe itching 
• Skin hyper-reactivity to environmental stimuli
• Redness - erythema
• Papulation – bump formation
• Oozing & crusting 

Environmental stimuli that may provoke the symptoms of atopic dermatitis include exposure to certain foods, inhaled allergens, skin irritants, and bacterial infection. Patients often have chronic skin lesions that are aggravated by abrasions from scratching (excoriations). They also frequently develop thickening of the skin (lichenification) in these areas. There are variants of the disease characterized predominantly by eyelid symptoms and occasionally lip eczema (atopic cheilitis). This latter condition results in lip peeling and fissuring.

Mild disease often results in intermittent flares of inflammation that are self-limited and resolve with minimal to no treatment. Moderate to severe disease may be characterized by skin changes that rarely clear without medical therapy. Patients may have symptoms lasting months to years in more severe cases.

Diagnosis

Atopic dermatitis is a clinical diagnosis based on symptoms, history, and physical examination. Major features of diagnosis include one or more of the following:

• Itchy skin (pruritus)
• Inflammation involving the skin creases
• Inflammation involving flexural surfaces
• Inflammation involving the cheeks or dorsal extremities
• History of asthma or allergic rhinitis
• Dry skin within the past year

In rare cases, your dermatologist may obtain immunoglobulin E levels or a skin biopsy to ensure that there is not another condition contributing to your symptoms. 

Eczema Medication and Treatment

The treatment of eczema involves eliminating triggers, restoring the skin barrier function, skin hydration, and medical treatment to reduce inflammation. Mild disease is usually treated with topical corticosteroids and emollients (moisturizers). Low potency corticosteroid cream or ointment may include Desonate (desonide 0.05%) or Cortizone (hydrocortisone 2.5%) applied once or twice daily for up to 1 month. Using this medication more frequently will not accelerate healing and may result in thin and easily breakable skin. 

Low potency corticosteroids are also generally indicated when there is involvement of the face or skin folds. Atopic dermatitis involving the face or skin folds that is refractory to topical corticosteroids may benefit from a class of medications known as topical calcineurin inhibitors such as Protopic (tacrolimus) or Elidel (pimecrolimus).

Moderate eczema is usually treated with medium to high potency corticosteroids such as Synalar (fluocinolone 0.025%), Aristocort (triamcinolone 0.1%), and betamethasone dipropionate 0.05%. Severe atopic dermatitis may warrant the use of phototherapy or in rare cases systemic immunosuppressants in adolescents. These therapies have a severely increased risk of side effects and must be carefully discussed with your physician. 

Skin hydration is also an important treatment consideration as the skin tends to get significantly dry with eczema. Dry skin also impedes skin healing. Some lotions can actually worsen dry skin as they have a low oil content, leading to increased dryness after the fluids in the lotion evaporate. Thick creams such as Eucerin or Cetaphil, or ointments such as Vaseline or Aquaphor are better at hydrating skin. Some patients complain that they result in greasiness of the skin, but other than this sensation they are very well tolerated and have minimal side effects.

References:

1. Weidinger S, Novak N. Atopic dermatitis. Lancet 2016; 387:1109. - https://www.ncbi.nlm.nih.gov/pubmed/26377142
2. Eichenfield LF, Tom WL, Berger TG, et al. Guidelines of care for the management of atopic dermatitis: section 2. Management and treatment of atopic dermatitis with topical therapies. J Am Acad Dermatol 2014; 71:116. - https://www.ncbi.nlm.nih.gov/pubmed/24813302