Update on atopic dermatitis: insights into pathogenesis and new treatment paradigms.

Atopic dermatitis (AD) is a common skin disorder whose prevalence has increased, similarly to other atopic diseases. The immunopathogenesis of AD is complex, although Staphylococcus aureus may play an important role in cutaneous inflammation, possibly resulting from a deficiency in antimicrobial peptide secretion in the skin. Although more than 50% of patients will go on to develop asthma and allergies, atopic dermatitis is often the start of the "atopic march." Studies with topical fluticasone provide a rationale for maintenance therapy, whereas studies with the topical nonsteroidal immunomodulator pimecrolimus in patients as young as 3 months of age suggest that early intervention may be an effective strategy in treating this chronic, relapsing skin disease.