A pilot study of antimicrobial photodynamic therapy of encapsulated Aspergillus fumigatus in a rabbit maxillary sinus model

摘要

Because fungi are present throughout the environment, humanexposure is inevitable and normal respiration will routinely depositfungal elements within the nose, paranasal sinuses, and in theremainder of the airway. In cases of immunosuppression orotherwise poor health, invasive aspergillosis may result in lethaloutcomes. Current approaches to treatment using azoles mayresult in severe hepatotoxicity and steroid treatment can inducediabetes and other negative sequelae. This pilot studydemonstrated that topical in vivo antimicrobial photodynamictherapy was capable of eradicating >3 log10 (>99.9%) of A.fumigatus inoculated into the NZW rabbit maxillary sinus in arecognized agar bead model of aspergillosis. This represents a>4,000-fold reduction in the number of viable conidia per unit area.These in vivo results closely matched in vitro experimental data inplanktonic and biofilm cultures. This pilot study will be replicated ina larger sample size and with polymicrobial cultures of importanthuman fungal pathogens including A. niger, A. flavus and M. indicus.