Atopic dermatitis (AD), also known as eczema, is a chronic and inflammatory skin condition that causes intense itchiness and redness.

This condition affects millions of people worldwide, primarily children, and is characterized by a defective skin barrier function and an exaggerated immune response. The primary goal of AD treatment is to reduce skin inflammation, protect the skin barrier and prevent itching.

However, many patients with AD report that topical or ‘epidermal’ solutions such as creams and ointments fail to control their symptoms adequately. In this article, we will discuss why epidermal solutions fail with atopic dermatitis.

The skin barrier in atopic dermatitis

The skin is the largest organ in the body and acts as a barrier between the external environment and the internal organs. The stratum corneum, the outermost layer of the skin, is composed of tightly packed layers of dead skin cells and lipids.

This layer plays a crucial role in maintaining skin hydration, regulating body temperature, and protecting the body from harmful agents such as bacteria, viruses, and chemicals. In patients with AD, the skin barrier function is impaired due to the decrease in the amount of lipids in the stratum corneum.

This depletion leads to increased transepidermal water loss, dehydration of the skin and increased susceptibility to infection. Furthermore, the impaired skin barrier function may facilitate the penetration of irritants and allergens into the skin, leading to an exaggerated immune response and skin inflammation.

The role of inflammation in AD

The immune response in patients with AD is characterized by increased levels of pro-inflammatory cytokines such as interleukin (IL)-4, IL-5, IL-13, and tumor necrosis factor-alpha (TNF-α).

These cytokines play a crucial role in recruiting immune cells such as T cells, eosinophils, and mast cells into the skin. These cells release further cytokines, chemokines, and mediators that promote skin inflammation, itchiness, and erythema.

In addition, patients with AD have impaired skin immunity and increased susceptibility to superinfection with bacteria such as Staphylococcus aureus.

The limitations of epidermal treatments in AD

Topical treatments such as corticosteroids, topical calcineurin inhibitors, and emollients are commonly used in the treatment of AD. These treatments aim to improve skin barrier function, reduce inflammation, and prevent itching.

However, many patients with AD have reported inadequate control of their symptoms with the use of these treatments. For example, corticosteroids used over long periods of time can cause skin thinning, stretch marks, and telangiectasia.

Topical calcineurin inhibitors such as tacrolimus and pimecrolimus have been associated with an increased risk of skin infections, lymphoma, and skin cancer. Moreover, adherence to treatment is often an issue, as patients may find the application of creams uncomfortable or time-consuming.

The importance of managing lifestyle factors in AD

It is important to recognize that AD is a multifactorial condition, and management of the symptoms requires a holistic approach.

The upkeep of a healthy lifestyle, including a balanced diet, regular exercise, adequate sleep, and avoidance of environmental triggers such as pollen and dust mites, can be beneficial in managing the symptoms. In addition, patients with AD can benefit from stress-management techniques, such as yoga and meditation, as stress has been identified as a significant trigger of AD flare-ups.

Patients should also avoid using harsh soaps and irritants, as these can exacerbate symptoms. Moreover, maintaining good hygiene, ensuring adequate sun protection, and avoiding overheating can play a vital role in keeping the skin healthy and reduce the risk of infections.

The potential of systemic treatments in AD

In severe cases of AD, where topical treatments fail to control symptoms adequately, systemic treatments may be necessary.

These treatments include oral immunosuppressants such as cyclosporine, oral corticosteroids, and biologic agents such as dupilumab. These treatments aim to reduce inflammation, improve skin barrier function and prevent itching. However, these treatments have potential side effects and require regular monitoring and close supervision by a dermatologist.

The future of AD treatment

Research into AD is ongoing, and new treatments are currently being developed. These treatments aim to address the underlying immune dysregulation and improve skin barrier function.

One such treatment is the use of skin microbiome transplants, which involves the transplantation of healthy bacteria from a healthy individual’s skin to the AD patient’s skin. By doing so, the skin microbiome is restored to a healthy state, and thus, the skin barrier function is improved.

Another treatment is the use of Janus kinase inhibitors, which inhibit the activity of JAK1 and JAK2 and have demonstrated efficacy in reducing skin inflammation and improving symptoms in patients with AD.

Conclusion

AD is a multifactorial condition, and management of symptoms requires a holistic approach.

While epidermal treatments such as creams and ointments are commonly used in the treatment of AD, they have limitations and may fail to control symptoms adequately in some patients. The importance of managing lifestyle factors, avoiding triggers, and seeking medical treatment when necessary cannot be overstated.

Ongoing research to develop new and improved treatments has the potential to significantly improve the quality of life for patients with AD.