title: A DNA dot hybridization model for assessment of bacterial bioburden in orthokeratology lens storage cases.
abstract: OBJECTIVE
  The aim of this study was to evaluate a DNA dot hybridization assay (DHA) for assessing bacterial bioburden in orthokeratology lens (OK) storage cases.
  
  
  METHODS
  Forty-one OK wearers participated in this study. The dot hybridization assay was used to assess the bacterial bioburden of OK after removal and 6-hour soaking in a storage case. Signals of the DHA were standardized after gray image transformation. The correlations between the hybridization intensities of three universal bacteria probes (BP1, BP2, and BP3) and bacterial bioburden determined by culture (colony forming units per milliliter) was analyzed by Pearson's correlation coefficient and receiver operating characteristic plots. In addition, three genus-specific probes for Pseudomonas, Acinetobacter, and Klebsiella were used to detect potentially hazardous bacterial contamination regardless of bacterial viability status.
  
  
  RESULTS
  Among the three universal probes, there were good correlations between probe BP2 (r2 = 0.31, P = 9.5 × 10(-5)) and probe BP3 (r2 = 0.35, P = 3.1 × 10(-5)) with bacterial bioburden, but no correlation was found between probe BP1 and bacterial bioburden (r2 = 0.04, P = 0.11). In 41 samples, one was Pseudomonas-positive by both DHA and culture, while 10 were Pseudomonas-positive by DHA but negative by culture. Furthermore, nine samples tested positive for Acinetobacter (n = 7) and Klebsiella (n = 2) by DHA only.
  
  
  CONCLUSIONS
  The dot hybridization assay provides a novel way to assess the bacterial bioburden of OK storage cases. Lens care quality can be assessed with universal bacteria probes, while potentially hazardous bacterial contamination can be traced with genus-specific probes.
authors.affiliation: Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Ming-Tse
authors.initials: MT
authors.lastname: Kuo
authors.affiliation: Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Chun-Chih
authors.initials: CC
authors.lastname: Chien
authors.affiliation: Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Jung
authors.initials: J
authors.lastname: Lo
authors.affiliation: Graduate Institute of Clinical Medical Sciences, Chang Gung University, Kaohsiung, Taiwan.
authors.forename: Chang-Chun
authors.initials: CC
authors.lastname: Hsiao
authors.affiliation: Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Shin-Ling
authors.initials: SL
authors.lastname: Tseng
authors.affiliation: Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Yu-Hsuan
authors.initials: YH
authors.lastname: Lai
authors.affiliation: Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Po-Chiung
authors.initials: PC
authors.lastname: Fang
authors.affiliation: Department of Medical Laboratory Science and Biotechnology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Tsung C
authors.initials: TC
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification*; D018407:Bacterial Physiological Phenomena; D018441:Biofilms / Q000254:growth & development; D002648:Child; D015169:Colony Count, Microbial; D003261:Contact Lenses / Q000382:microbiology*; D015342:DNA Probes / Q000737:chemistry; D004269:DNA, Bacterial / Q000032:analysis*; D004866:Equipment Contamination; D005260:Female; D006801:Humans; D008297:Male; D009693:Nucleic Acid Hybridization / Q000379:methods*; D054158:Orthokeratologic Procedures / Q000295:instrumentation*; D016133:Polymerase Chain Reaction; D019064:Product Packaging; D011446:Prospective Studies
chemical_list: D015342:DNA Probes; D004269:DNA, Bacterial
keywords: bacterial bioburden; dot hybridization assay; lens storage case; orthokeratology