Could We Suppress S. aureus on Atopic Dermatitis Skin?
Student Summary by Olivia Liu
Original Source: Teruaki Nakatsuji, Richard L. Gallo, & others. JAMA Dermatology, June
16, 2021.
Image Created by Olivia Liu
Abstract
Background: Having been noted since 1974, there has been a strong connection between atopic dermatitis, an inflammatory skin condition characterized by dry, itchy skin, and Staphylococcus aureus, a bacterium that can cause skin infection. People who are found with this skin disorder produce a lower amount of antimicrobial peptides and have an abnormal skin microbiome, allowing S. aureus to inhabit the skin more easily. It was also found that patients with atopic dermatitis lack coagulase-negative Staphylococcus (CoNS), which are capable of producing antimicrobials (AM) that prevent the growth of S. aureus.
Objective: Researchers wanted to know if constantly applying CoNS-AM onto skin that has been affected by atopic dermatitis, would reduce/suppress S. aureus survival.
Method: Researchers swabbed each patient’s non-lesional (healthy-looking) skin (from 11 patients) to collect their personal CoNS bacteria. Only CoNS strains that could kill that patient’s own S. aureus were selected (a personalized match). The selected CoNS were cultured (grown) overnight and then formulated at 10⁷ colony-forming units per gram of lotion. The bacteria were mixed into Cetaphil lotion, confirmed not to harm bacterial viability. The vehicle group received lotion with saline only (control).
Results: After one week of twice-daily treatment, S. aureus colonization on lesional skin was reduced by 99.2% compared with the vehicle group. The effect lasted after treatment ended (S. aureus suppression persisted for 4 days after the last application).
Conclusion: This autologous bacteriotherapy reduced S. aureus by 99.2% and improved eczema severity by ~48%. Side effects were low and the bacteria didn’t accumulate. This personal bacteriotherapy method is an effective approach to be used in the future.
