Use of Autologous Bacteriotherapy to Treat Staphylococcus aureus in Patients With Atopic Dermatitis

Importance

Atopic dermatitis (AD) can be negatively affected byStaphylococcus aureus. The skin microbiome of AD is deficient in coagulase-negativeStaphylococcus(CoNS) that can killS aureus.

Objective

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 ofS aureusand improve clinical outcomes.

Design, Setting, and Participants

This double-blind, vehicle-controlled, single-center randomized clinical trial of 11 adult patients with moderate to severe AD who were randomized to receive either an autologous CoNS-AM+ (n = 5) or the vehicle (n = 6) was conducted between April 2016 and May 2018. The data were analyzed from May 2018 to July 2019.

Interventions

Autologous CoNS-AM+ was isolated from swabs that were obtained from the nonlesional skin of each patient with AD, expanded by culture, and then reapplied topically to the forearms at a concentration of 10⁷colony-forming units/g.

Main Outcomes and Measures

The primary end point of this study was to assessS aureusabundance after 1 week of application of autologous CoNS-AM+ on patients with AD by culture-based and DNA-based methods. The secondary end points were to assess the safety and clinical outcomes.

Results

Eleven patients (4 men [36.4%] and 7 women [63/6%]) were recruited based on the inclusion criteria. There were no serious adverse events in groups treated with autologous CoNS-AM+ or the vehicle.Staphylococcus aureuscolonization on lesional skin at the end of treatment on patients who were treated with autologous CoNS-AM+ (mean of log10 ratio to baseline, −1.702; 95% CI, −2.882 to −0.523) was reduced by 99.2% compared with vehicle treatment (mean of log10 ratio to baseline, 0.671; 95% CI, −0.289 to 1.613;P = .01) and persisted for 4 days after treatment (CoNS-AM+: mean of log10 ratio to baseline, −1.752; 95% CI, −3.051 to −0.453; vehicle: mean of log10 ratio to baseline, −0.003; 95% CI, −1.083 to 1.076;P = .03). Importantly, local Eczema Area And Severity Index scores that were assessed at day 11 on patients who received CoNS-AM+ (mean of percentage change, −48.45; 95% CI, −84.34 to −12.55) were significantly improved compared with vehicle treatment (mean of percentage change, −4.52; 95% CI, −36.25 to 27.22;P = .04).

Conclusions and Relevance

The data from this randomized clinical trial suggest that bacteriotherapy with an autologous strain of skin commensal bacteria can safely decreaseS aureuscolonization and improve disease severity. Although larger studies will be needed, this personalized approach forS aureusreduction may provide an alternative treatment for patients with AD beyond antibiotics, immunosuppression, and immunomodulation.

Trial Registration

ClinicalTrials.gov Identifier:NCT03158012