Clinical Presentation and Diagnosis
Patients with AD present acutely with pruritic, erythematous, scaly papules, and plaques. These lesions usually involve the antecubital and popliteal fossae, hands, neck, and face, especially the periorbital and perioral skin. If severe, weeping and crusting may be present. The intense itching results in scratching of the skin, leading to subacute and chronic changes such as lichenification, excoriations, and hyperpigmentation of the affected areas. The open areas of the skin are susceptible to superinfection with S aureus (impetiginization) and secondary infection with herpes simplex virus (eczema herpeticum); this susceptibility is thought to be secondary to barrier dysfunction, as well as immunologic changes. As a result of the intense itching, sleep disturbance is one of the major symptoms affecting patients with AD.
The clinical presentation of AD is age-dependent and the condition is thus divided into infantile, childhood, and adult stages. In infants, AD begins as dry patches associated with itching; the cheeks and hands are most affected, as these areas are accessible to scratching and rubbing by the infant. The diaper area is typically spared, since this area is somewhat less affected by barrier dysfunction. In toddlers and school-aged children, scaly papules and plaques are usually seen on the antecubital and popliteal fossae and the neck. Adult AD is typically distributed on the hands, neck, and face. In children and adults, handwashing contributes to involvement of the hands, which can be especially debilitating.
There is no laboratory test for AD, as the diagnosis of AD is based on specific criteria with clinical features as mentioned earlier. It is important to rule out other common diseases that can cause pruritus, such as scabies, seborrheic dermatitis, contact dermatitis, and psoriasis. A skin biopsy is sometimes, but not always, helpful in distinguishing between these disorders. If a patient is not responding to therapy for AD, other systemic disorders — including more serious nutritional, metabolic, and immunologic conditions in children and cutaneous T-cell lymphoma in adults — should be considered. Further laboratory work-up such as patch testing, complete blood count, serum chemistry, allergy and immunology studies, and genetic evaluation may be warranted.
The severity of AD in the clinical setting is usually described as mild, moderate, or severe. For the purpose of clinical trials, as well as for evaluation for systemic therapy, severity can be assessed based on the SCORing AD (SCORAD) index. This is based on the extent, intensity, and subjective symptoms (itching and sleeplessness) of AD in a standardized manner. A SCORAD score below 20 is regarded as “mild” AD, whereas a score greater than 40 is generally regarded as “severe” disease. The importance of sleep disturbance in the patient and the patient’s family cannot be overstated and contributes to the tremendous impact of AD.
According to guidelines published and updated in the Journal of American Academy of Dermatology,7 management of AD is a multistep process that involves primary, secondary, and tertiary measures. Treatment may vary between individuals and can include pharmacologic and nonpharmacologic interventions.
Primary Prevention or Avoidance Strategy
Primary prevention involves avoidance of incitement factors, as well as nonpharmacologic interventions such as avoidance of allergens, cleansing and bathing, and dietary modifications. Although there is no standard established or scientific data concerning the suggested duration and frequency of bathing appropriate for AD, it has been suggested that patients with AD bathe as a part of their treatment. Not only does bathing hydrate the skin, a crucial step in treating AD, but it also removes allergens/irritants that cause AD symptoms and removes the scale crust that can stimulate the inflammation process. Neutral to low pH, hypoallergenic, and fragrance-free cleansers should be used, followed by moisturizers to maintain skin hydration.