title: [In-vitro study of photodynamic therapy of antibiotic-resistant staphylococcus from patients with chronic rhinosinusitis].
abstract: OBJECTIVE
  To evaluate the photodynamic therapy (PDT) against multi-antibiotic-resistant Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S.epidermidis) obtained from patients with chronic rhinosinusitis (CRS).
  
  
  METHODS
  Forty-five CRS patients who had been given medical treatment but still needed endoscopic surgery were included in this study. The mucus from middle meatus was collected from these patients during surgery, followed by separation of S. aureus and S. epidermidis and drug sensitive test. The strains which could form biofilm were selected. Light emitting diode (LED) array with a major wavelength of (633±10) nm was used as light source and 5-Aminolevulinic acid (ALA) was used as photosensitizer in this PDT experiment. The safe range of LED dose and ALA concentration which were not toxic to bacteria by themselves were confirmed, and then did PDT experiment on S. aureus and S. epidermidis. The data of bacterial colony forming unit were transformed to lgCFU before statistical analysis.The Graph Pad Prism 5 software was used to analyzed the data.
  
  
  RESULTS
  Thirteen S. aureus and 16 S. epidermidis were included in this experiment(from 45 patients), all of them were multi-antibiotic-resistant bacteria, and four of S. aureus and five of S. epidermidis could form biofilm in each group. In planktonic S. aureus experiment, the mean lgCFU was 8.32±0.31 in control group whereas the experiment group was 6.47±0.67 (t=9.01, P<0.01), and in planktonic S. epidermidis experiment the final data was 8.34±0.20 (control group) and 6.97±0.59 (experiment group) (t=8.84, P<0.01). In biofilm S. aureus experiment, the mean lgCFU was 8.68±0.05 (control group), 6.90±0.96(experiment group) (t=3.68, P<0.05); and in biofilm S. epidermidis experiment the data was 8.67±0.05 (control group), 7.29±0.61 (experiment group, t=5.07, P<0.01).
  
  
  CONCLUSIONS
  Our results demonstrated that ALA-mediated PDT on multi-antibiotic-resistant S. aureus and S. epidermidis from CRS patients was effective in vitro. Additional work defining if the PDT treatment would damage the nasal mucosa and further checking the effectiveness of PDT in vivo is still needed.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai 200031, China.
authors.forename: Keqing
authors.initials: K
authors.lastname: Zhao
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai 200031, China; Department of Otorhinolaryngology-Head and Neck Surgery, Ruijin Hospital, Shanghai Jiaotong University, Shanghai 200025, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Yang
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai 200031, China.
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Ding
authors.affiliation: Department of Clinical Laboratory, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai 200031, China.
authors.forename: Chunhong
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Dermatology, Huashan Hospital, Fudan University 200040, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Dermatology, Ruijin Hospital, Shanghai Jiao Tong University, Shanghai 200025, China.
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Chen
authors.affiliation: School of Basic Medical Science and Institutes of Biomedical Sciences, Shanghai Medical College of Fudan University, Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai 200032, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Eye, Ear, Nose and Throat Hospital, Fudan University, Shanghai 200031, China.
authors.forename: Chunquan
authors.initials: C
authors.lastname: Zheng
mesh_terms: D000622:Aminolevulinic Acid / Q000627:therapeutic use; D000900:Anti-Bacterial Agents; D018441:Biofilms; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D008027:Light; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use; D012220:Rhinitis / Q000188:drug therapy* / Q000382:microbiology; D012852:Sinusitis / Q000188:drug therapy* / Q000382:microbiology; D013203:Staphylococcal Infections / Q000150:complications / Q000188:drug therapy*; D013210:Staphylococcus
chemical_list: D000900:Anti-Bacterial Agents; D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid