INTRODUCTION
Atopic dermatitis (AD) is a chronically relapsing, inflammatory
and pruritic skin disease. In industrialized countries,
the prevalence of AD is 10−20 percent in children
and 1−3 percent in adults.1 Acute exacerbations present clinically
as pruritic, erythematous papules with excoriation and serous
exudates.2,3 Chronic disease is characterized by dry, scaly
skin (xerosis) and thickened, lichenified skin with fibrotic papules.
Xerosis signifies a compromised epidermal barrier and
can lead to disease exacerbation or skin infections.2,4 Patients
with moderate-to-severe AD experience an average of seven to
nine flares per year, with the average flare lasting 16 to 19 days.5
Flare reduction is essential in effective, long-term management
of AD, although it is quite challenging due to the chronic and
relapsing nature of the disease process.
Currently, the best clinical practice in the long-term management
of AD requires a multi-therapeutic approach, which
includes resolving short-term flares, controlling symptoms
between major flares and prolonging the time until the subsequent
flare.6 The most commonly used treatment modalities are
emollients, topical corticosteroids (TCS), and topical calcineurin inhibitors (TCIs). TCS are the mainstay of treatment; however,
long-term use of super-potent TCS is not desirable due to a
multitude of side effects. Localized cutaneous side effects include
skin atrophy, telangiectasia, dyspigmentation, rosacea,
dermatitis, acne and impairment of the epidermal barrier.7-11
Tachyphylaxis, or decreased medication efficacy, may also
occur as a side effect with repeated administration, causing disease
relapse after discontinuation.12,13 While not as prevalent,
systemic side effects may occur if the applied TCS penetrates
into the circulation; this may only been seen if super-potent
TCS are used hastily for long periods with high frequency and
large applications. Systemic side effects can be detrimental and
include suppression of the hypothalamic-pituitary-adrenal axis
(HPA), growth retardation in children, and cataract and glaucoma
formation.14-17 Until recently, the only options for patients
unresponsive to or requiring frequent application of TCS were
oral systemic therapies such as corticosteroids or immunosuppressive
medications such as cyclosporine, methotrexate,
azathioprine, or mycophenolate mofetil, which are all associated
with distinctive, serious systemic side effects.18