Atopic Dermatitis: Overview of Current Diagnosis

What to Know

No clear consensus has emerged regarding the diagnostic work-up that should be performed when evaluating patients with AD, particularly in adult patients. Diagnostic approaches vary widely.¹
Chronic pruritus/itching induces scratch behavior. While this can serve as a physiologic self-protective mechanism to prevent the body from being hurt by harmful external agents, it also damages skin and increases inflammation. This further exacerbates pruritus and often leads to the ‘‘itch-scratch cycle.’’²
Clinical phenotypes and endophenotypes are characterized by a wide range of heterogeneity in the onset, course, and presentation of AD, as well as in individual comorbidities.
The diagnosis of AD remains clinical because there are no known reliable biomarkers that can distinguish AD from other diseases.^3,4
Guidelines for the management of AD issued in 2014 reported 28 different scales for the measurement of disease severity, without a single gold standard emerging.⁴

Symptoms and Physical Findings The main physical findings associated with AD include xerosis, lichenification, and eczematous lesions. Eczematous changes are seen in varying locations, depending on the age of the patient (infant, child, or adult).¹ (Figure 1)

The following symptoms and features are also commonly seen in AD:

Pruritus
Chronic and relapsing course
Early age of onset
Peripheral eosinophilia
Immunoglobulin (Ig) E reactivity
Staphylococcus aureus superinfection
Personal history of asthma or hay fever
History of atopic diseases in a first-degree relative¹

Diagnosis: American Academy of Dermatology

According to the American Academy of Dermatology,^2,3 patients with presumed AD should have their diagnosis made based on a combination of features.

Essential Features^2,3(must be present)

Important Features^2,3
(support diagnosis; seen in most cases)

· Pruritus
· Eczema (acute, subacute, chronic)
· Typical morphology and age-specific patterns*
· Chronic or relapsing history

*Patterns include:
1. Facial, neck, and extensor involvement in infants/children
2. Current/previous flexural lesions at any age
3. Sparing of the groin and axillary regions

· Early age of onset
· Atopy
· Personal and/or family history
· IgE reactivity
· Xerosis

“Associated features” help suggest the diagnosis of AD but are nonspecific.^2,3 These include:

Atypical vascular responses
Keratosis pilaris, pityriasis alba, hyperlinear palms, and ichthyosis
Ocular/periorbital changes
Perifollicular accentuation, lichenification, and prurigo lesions

In addition, other conditions must be excluded, such as scabies, seborrheic dermatitis, contact dermatitis, ichthyosis, cutaneous T-cell lymphoma, psoriasis, photosensitivity dermatoses, immunodeficiency diseases, and erythroderma of other causes.^2,3

For additional information on the diagnosis of AD, we encourage you to visit the following references as well as our “Additional Reading” sections.

References

Kim BS. Atopic dermatitis. Updated June 3, 2020 (https://emedicine.medscape.com/article/1049085-overview).
American Academy of Neurology. Atopic dermatitis clinical guideline (https://www.aad.org/practicecenter/quality/clinical-guidelines/atopic-dermatitis/diagnosis-and-assessment).
Eichenfield LF, et al. Guidelines of care for the management of atopic dermatitis: section 1. Diagnosis and assessment of atopic dermatitis. J Am Acad Dermatol. 2014;70:338-351.