Episode 205: Atopic Dermatitis 

Kara Willbanks (medical student) explains the definition, pathophysiology, and treatment of eczema. Dr. Arreaza adds some input about bleach baths and topical steroids. 

Written by Kara Willbanks, MSIV, American University of the Caribbean. Comments and edits by Hector Arreaza, MD.

You are listening to Rio Bravo qWeek Podcast, your weekly dose of knowledge brought to you by the Rio Bravo Family Medicine Residency Program from Bakersfield, California, a UCLA-affiliated program sponsored by Clinica Sierra Vista, Let Us Be Your Healthcare Home. This podcast was created for educational purposes only. Visit your primary care provider for additional medical advice.

October is the Eczema Awareness Month!

What Is Atopic Dermatitis? 

Atopic dermatitis, a form of eczema, is a chronic, relapsing inflammatory skin disorder that often begins in childhood but can affect people of all ages. 

Other eczematous dermatoses include seborrheic dermatitis, contact dermatitis, juvenile plantar dermatosis, and stasis dermatitis. 

Atopic dermatitis is one of the most common skin conditions in the developed world, typically affecting up to 20% of children and 5-10% of adults. Patients usually present with severe pruritus (itchiness) and dry, inflamed patches of skin. Common sites include the face and extensor surfaces in infants, and flexural areas — like the elbows and knees — in older children and adults. 

Atopic dermatitis is often associated with other allergic conditions like asthma and allergic rhinitis — what we call the “atopic triad.” These conditions should also be considered when diagnosing someone with atopic dermatitis. 

Pathophysiology

Atopic dermatitis is believed to occur due to a combination of genetic, immune, and environmental factors. A major component is a defective skin barrier, often linked to mutations in the filaggrin gene. This allows irritants, allergens, and microbes to penetrate the skin more easily, triggering inflammation.

Differential Diagnosis

Atopic dermatitis can sometimes mimic other skin conditions, so it’s important to keep a differential in mind: 

-Contact dermatitis – triggered by allergens or irritants; often limited to the area of exposure but also tends to be very itchy. 

-Seborrheic dermatitis – greasy scales, typically on the scalp, eyebrows, and nasolabial folds 

-Psoriasis – well-demarcated plaques with silvery scales; sometimes found in similar areas of the body as eczema. 

-Tinea (fungal infections) – ring-shaped lesions with active, scaly borders -Important to note that treatment of tinea with topical steroids can make the rash much worse. 

-Scabies – intense itching, especially at night, with burrows between fingers. 

Ruling out these conditions helps guide the right treatment and prevent chronic mismanagement. As a recap our main differential diagnosis: contact dermatitis, seborrheic dermatitis, psoriasis, tinea, and scabies.

The treatment cornerstone: Moisturizers 

The most important daily treatment for atopic dermatitis is regular moisturizing. Moisturizers repair the skin barrier, reduce water loss, and protect against irritants. They should be applied at least twice daily, ideally right after bathing while the skin is still damp (within 3 minutes is most ideal). Use greasy ointments or thick creams rather than lotions — think products with ceramides or glycerin (hydrates and protects skin). 

It is best to choose ointments or creams without additives, perfumes or fragrances. Greasier ointments are the preferred vessel; however, patient compliance may be less as they may be unpleasant to some.

Bleach Baths 

For patients with frequent skin infections or severe eczema, dilute bleach