Atopic dermatitis

Atopic dermatitis is a chronic inflammatory cutaneous disease. It is known for manifesting in outbreaks, being reversible and for unpredictable progression during the patient’s life. The most frequent cutaneous disease in children. Patients have very itchy, dry skin, as well as a hyperactive immune response to environmental factors. Intense itchiness leads to uncontrolled scratching, which causes wounds on the eczema. These can be complicated by infection and can cause great anxiety in patients and their families. 

Atopic dermatitis is a multifaceted disease caused by a combination of many factors, including: 

• skin components: cellular and extracellular components that form the skin barrier
• innate and adaptive immune system. Innate immunity is present from birth and acts as the first line of defence against infectious agents. Adaptive immunity is acquired throughout life depending on the infections we are exposed to. 
• cutaneous microbiome (different microbes that form part of normal skin)  
• genetic factors
• environmental factors

Symptoms

Common symptoms of atopic dermatitis are: 

• dry skin 
• itchy skin, leading to uncontrollable scratching and wounds
• eczemas which manifest as areas of reddened skin with peeling; they may be acute, subacute or chronic
• hyperactive response to environmental factors that can trigger eczema in the form of outbreaks

Clinical presentation, characteristics of symptoms and initial signs depend on the patient’s age but, in all cases, axillary and inguinal folds are usually unaffected.

• Infants (under 2): affects the face, cradle cap, neck and limb extensor areas.
• School age children: affects the face and predominantly arm and leg flexor areas (antecubital fossa in the elbow and popliteal fossa in the knee).
• Adults: can be just as extensive as in children or be limited to the sides of the neck and back of the hands and feet.

Who is affected by the condition? 

The most frequent cutaneous disease in children. Usually begins during childhood and most cases are resolved during adolescence. Although some paediatric patients are affected by the disease until adulthood. Atopic dermatitis can also sometimes begin in adults, young adults or even at an advanced age.  

Diagnosis 

Atopic dermatitis is always diagnosed according to clinical criteria and generally does not require complementary tests. Currently, diagnosis and assessment of the severity of the disease are clinical with the doctor examining the patient.

A skin biopsy should be considered to exclude other conditions, including early stage T-cell cutaneous lymphoma, psoriasis or dermatitis herpetiformis.

Atopic dermatitis is not an allergic condition but children with the disease may suffer:  

• food allergies
• asthma
• rhinitis
• skin sensitivity to external substances

If rhinitis, allergic conjunctivitis or any food allergy is associated or suspected, the patent will be referred to the Allergology Department. 

Typical treatment 

The main goal of treatment is to maintain the skin free from eczema outbreaks. Therefore, hygiene measures will be prescribed to keep the skin moisturised and less susceptible to inflammation. External factors that can trigger skin inflammation should also be avoided.

Topical corticosteroids, topical immunomodulators and oral antihistamines are used to control minor to moderate outbreaks of atopic dermatitis in order to reduce inflammation and itchiness. Topical or oral antibiotics may be necessary in case of eczema superinfection. 

Controlling severe outbreaks may require systemic treatment, such as:

• oral corticosteroids
• phototherapy
• ciclosporin
• azathioprine
• methotrexate
• mycophenolate mofetil or recently approved biological treatments

Prevention

Prevention is essential to avoid the inflammatory response associated with eczema:

• Avoid irritating external factors
• Keep skin well moisturised