title: Efficacy of antifungal PACT in an in vitro model of onychomycosis.
abstract: BACKGROUND
  The difficulty of antifungal substances to penetrate keratin and slow nail growth limit the efficacy of topical therapy in onychomycosis. One promising alternative is photodynamic antimicrobial chemotherapy, or PACT: an irradiated photosensitizer creates singlet oxygen molecules which destroy pathogens without damaging human cells.
  
  
  OBJECTIVE
  As PACT has demonstrated strong antifungal capabilities, we wanted to investigate its efficacy in an in vitro model of onychomycosis.
  
  
  METHODS
  PACT was tested in a microdilution assay, in an in vitro onychomycosis model as well as in a patient.
  
  
  RESULTS
  PACT inhibited fungal growth in the microdilution assay with no colonies of T. rubrum detectable. Fungal growth was also inhibited in an onychomycosis model, after 30 min of LED irradiation. Subsequently, a patient with distolateral onychomycosis was treated on three consecutive days and showed significant and durable improvement of nail morphology 6 months after.
  
  
  CONCLUSIONS
  PACT appears to be an effective treatment of onychomycosis in vitro. The promising results need to be validated by clinical trials.
authors.affiliation: Department of Dermatology, Eberhard-Karls-University, Tübingen, Germany; Ärztliche Direktion, Abteilung Medizincontrolling, UniversitätsSpital Zürich, Zürich, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Mehra
authors.forename: M
authors.initials: M
authors.lastname: Schaller
authors.forename: B
authors.initials: B
authors.lastname: Walker
authors.forename: C
authors.initials: C
authors.lastname: Braunsdorf
authors.forename: D
authors.initials: D
authors.lastname: Mailänder-Sanchez
authors.forename: F
authors.initials: F
authors.lastname: Schynowski
authors.forename: R
authors.initials: R
authors.lastname: Hahn
authors.forename: M
authors.initials: M
authors.lastname: Röcken
authors.forename: M
authors.initials: M
authors.lastname: Köberle
authors.forename: C
authors.initials: C
authors.lastname: Borelli
mesh_terms: D015169:Colony Count, Microbial; D005260:Female; D005533:Foot Dermatoses / Q000188:drug therapy*; D005782:Gels; D006801:Humans; D008027:Light; D008875:Middle Aged; D014009:Onychomycosis / Q000188:drug therapy*; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000627:therapeutic use*; D014048:Tolonium Chloride / Q000627:therapeutic use*; D014249:Trichophyton / Q000187:drug effects* / Q000254:growth & development
chemical_list: D005782:Gels; D017319:Photosensitizing Agents; D014048:Tolonium Chloride