A Comparative Clinical Trial to Evaluate the Efficacy and Safety of Tacrolimus Versus Hydrocortisone in Treatment of Children With Atopic Dermatitis

Atopic dermatitis is a common pruritic inflammatory skin disorder. The prevalence of atopic dermatitis increased in the last three decades by two or three folds worldwide. In the developed countries, atopic dermatitis is estimated to affect 15% to 30% of children and 2% to 10% of adults. This type of dermatitis is usually associated with family history of other atopic disorders such as allergic rhinitis or asthma.

The clinical presentation of Atopic dermatitis differs depending on the age of the patient, it usually begins in infancy with erythematous, papular skin rash that may first appear on the cheeks and chin. In childhood, the skin appears dry, flaky, rough, cracked, and may bleed because of scratching, in adults the lesions are more diffuse with underlying erythema.

This condition is characterized by acute phase where the skin has red scaly patches and chronic phase in which the skin thickens.

Atopic dermatitis is a complex genetic disease where the exact etiology is not entirely known, but it is most probably due to interaction between environmental and genetic factors. The two major groups of involved genes are the genes encoding for epidermal and epithelial structural proteins and the genes regulating the production of cytokines for the immune response.

In atopic dermatitis patients, imbalance occurs between T helper-1 (TH1) and T helper-2 (TH2) immune responses, increased TH2 activity causes the release of interleukin (IL)-3, IL-4, IL-5, IL-10, and IL-13 which results in blood eosinophilia, increased total serum immunoglobulin (Ig) E, and increased growth and development of mast cells.