This paper studied whether mupirocin, a topical antibiotic, could help treat atopic dermatitis by reducing Staphylococcus aureus bacteria on the skin. The study looked at both the bacteria levels and clinical symptoms before and after treatment.

The researchers conducted a double-blind, placebo-controlled crossover study. They measured bacteria levels on patients' skin before treatment, after 2 weeks of either mupirocin or placebo treatment, and during a 4-week follow-up period.

The study included 49 patients with atopic dermatitis (45 completed the study). Almost all patients had heavy colonization of Staphylococcus aureus on their skin, even without visible infection.

Mupirocin significantly reduced both bacteria levels and clinical symptoms after 2 weeks of treatment, while placebo did not. Although bacteria levels returned to pre-treatment levels during the 4-week follow-up, clinical improvements were maintained. Half of the patients carried more than one type of bacteria, and 17% of patients were recolonized with new bacterial strains.

The authors concluded that mupirocin effectively reduces both Staphylococcus aureus colonization and clinical symptoms in atopic dermatitis. The treatment was safe with no serious side effects. Even though bacteria returned after treatment stopped, patients' symptoms didn't get worse during the study period.