Anna Carolina Ratto Tempestini HORLIANA DDS, PhD, Professor

• Department of Biophotonics Applied to Health Sciences, Postgraduate Program – Nove de Julho University, São Paulo, Brazil.
• Master in Dentistry Sciences – University of São Paulo (FOUSP)
• Ph.D. in Dentistry Sciences – University of São Paulo (FOUSP)
• Pos doc in Periodontics – University of São Paulo (FOUSP)

Title: Effect of antimicrobial photodynamic therapy in the nasal decolonization of chronic hemodialysis patients: A single-blind randomized pilot study

Background: Infections by Staphylococcus aureus are an important cause of mortality in patients with Chronic Kidney Disease (CKD) undergoing hemodialysis (HD) treatment. It is known that previous nasal colonization with this agent is a risk factor for infection. Nasal decolonization reduces infection rates; however, the repeated gold-standard treatment induces resistance. Antimicrobial photodynamic therapy (aPDT) is a promising treatment due to its bactericidal effect and does not induce resistance. Therefore, this study aims to compare aPDT with mupirocin for nasal decolonization among nasal carriers of Staphylococcus aureus in hemodialysis patients. Material and methods: A randomized, controlled follow-up pilot study of 34 participants distributed into G1 (n=17) – decolonization with aPDT (λ= 660 nm, 400 mW/cm², 300 seconds, methylene blue 0.01%, single application), G2 (n=17) – decolonization with mupirocin (twice a day, 5 days). Nasal swabs were collected to identify the carrier state, after the intervention,1 and 3 months.  Results: All 17 participants randomized to photodynamic therapy and 13 of 17 (77%) randomized to mupirocin were adherent to treatment. Among the participants, 12/17 (71%) had negative cultures compared with 13/17 (77%) treated with mupirocin (P=1.000; RR 0.92, CI 0.61 to 1.38). Moreover, 67% of patients who had negative cultures at T1 were recolonized within 3 months. There were no adverse events in the photodynamic therapy group. Limitations: Restricted to nasal colonization and infectious complications were not assessed. Conclusions: Photodynamic therapy is a feasible approach to treating Staphylococcus aureus nasal carriage. Future larger studies should be conducted to determine if photodynamic therapy is equivalent to the standard of care with mupirocin.

 Funding National Council for Scientific and Technological Development – CNPq (process:3146682020-9) Trial Registration NCT 04047914