USA: A bacteriotherapy with an autologous strain of bacteria may safely improve the microbiome of patients with Atopic Dermatitis and improve disease severity, according to a study published in the journal JAMA Dermatology.

Atopic Dermatitis (AD), also known as Eczema, is an itchy inflammation of the skin that worsen in the presence of certain irritants or triggers and can also be negatively affected by Staphylococcus aureus. Coagulase-negative staphylococcus (CoNS), that can kill S. aureus, is deficient in the microbiome of patients with AD.

So, researchers from the Department of Dermatology at the University of California carried out a study to evaluate if the antimicrobial-producing CoNS (CoNS-AM+) of a patient with AD can be autologously reintroduced to the same patient to inhibit survival of S aureus and improve clinical outcomes.

They carried out a double-blind, vehicle-controlled, single-center randomized clinical trial of 11 adult patients with moderate to severe AD. The participants were randomized to receive either an autologous CoNS-AM+ or the vehicle, between April 2016 and May 2018. The data were analyzed from May 2018 to July 2019. Autologous CoNS-AM+ was isolated from swabs that were obtained from the non-lesional skin of the patients, expanded by culture, and then reapplied topically to the forearms at a concentration of 10⁷ colony-forming units/g.

The primary end point of this study was to assess S aureus abundance after 1 week by culture-based and DNA-based methods. The secondary end points were to assess the safety and clinical outcomes.

The study showed the following results:

• There were no serious adverse events in groups treated with autologous CoNS-AM+ or the vehicle.
• Staphylococcus aureus colonization on lesional skin at the end of treatment on patients who were treated with autologous CoNS-AM+ was reduced by 99.2% compared with vehicle treatment and persisted for 4 days after treatment.
• Local Eczema Area And Severity Index scores that were assessed at day 11 on patients who received CoNS-AM+ were significantly improved compared with vehicle treatment.

These findings suggest that a bacteriotherapy with an autologous strain of bacteria may safely improve S. aureus colonization in the microbiome of patients with AD and improve disease severity.

"Although larger studies will be needed, this personalized approach for S aureus reduction may provide an alternative treatment for patients with AD beyond antibiotics, immunosuppression, and immunomodulation," the investigators concluded.

Reference:

Study titled, "Use of Autologous Bacteriotherapy to Treat Staphylococcus aureus in Patients With Atopic Dermatitis: A Randomized Double-blind Clinical Trial," published in the Journal of American Medical Association, Dermatology.

DOI: 10.1001/jamadermatol.2021.1311