@article{TEXTUAL,
      recid = {6247},
      author = {Chun, Lindsay Y. and Dolle-Molle and Bethel, Cindy and  Dimitroyannis, Rose C. and Williams, Blake L. and Schechet,  Sidney A. and Hariprasad, Seenu M. and Missiakas, Dominique  and Schneewind, Olaf and Beavis, Kathleen G. and Skondra,  Dimitra},
      title = {Rapid pathogen identification and antimicrobial  susceptibility testing in &amp;lt;i&amp;gt;in vitro&amp;lt;/i&amp;gt;  endophthalmitis with matrix assisted laser  desorption-ionization Time-of-Flight Mass Spectrometry and  VITEK 2 without prior culture},
      journal = {PLOS ONE},
      address = {2019-12-30},
      number = {TEXTUAL},
      abstract = {&lt;p&gt;Purpose: Prompt clinical diagnosis and initiation of  treatment are critical in the management of infectious  endophthalmitis. Current methods used to identify causative  agents of infectious endophthalmitis are mostly  inefficient, owing to suboptimal sensitivity, length, and  cost. Matrix Assisted Laser Desorption-Ionization  Time-of-Flight Mass Spectrometry (MALDI-TOF MS) can be used  to rapidly identity pathogens without a need for culture.  Similarly, automated antimicrobial susceptibility test  systems (AST, VITEK 2) provide accurate antimicrobial  susceptibility profiles. In this proof-of-concept study, we  apply these technologies for the direct identification and  characterization of pathogens in vitreous samples, without  culture, as an in vitro model of infectious  endophthalmitis.&lt;/p&gt; &lt;p&gt;Methods: Vitreous humor aspirated  from freshly enucleated porcine eyes was inoculated with  different inocula of Staphylococcus aureus (S. aureus) and  incubated at 37°C. Vitreous endophthalmitis samples were  centrifuged and pellets were directly analyzed with  MALDI-TOF MS and VITEK 2 without prior culture. S. aureus  colonies that were conventionally grown on culture medium  were used as control samples. Time-to-identification,  minimum concentration of bacteria required for  identification, and accuracy of results compared to  standard methods were determined.&lt;/p&gt; &lt;p&gt;Results: MALDI-TOF  MS achieved accurate pathogen identification from direct  analysis of intraocular samples with confidence values of  up to 99.9%. Time from sample processing to pathogen  identification was &lt;30 minutes. The minimum number of  bacteria needed for positive identification was 7.889x106  colony forming units (cfu/μl). Direct analysis of  intraocular samples with VITEK 2 gave AST profiles that  were up to 94.4% identical to the positive control S.  aureus analyzed per standard protocol.&lt;/p&gt; &lt;p&gt;Conclusion:  Our findings demonstrate that the direct analysis of  vitreous samples with MALDI-TOF MS and VITEK 2 without  prior culture could serve as new, improved methods for  rapid, accurate pathogen identification and targeted  treatment design in infectious endophthalmitis. In vivo  models and standardized comparisons against other  microbiological methods are needed to determine the value  of direct analysis of intraocular samples from infectious  endophthalmitis with MALDI-TOF MS and VITEK 2.&lt;/p&gt;},
      url = {http://knowledge.uchicago.edu/record/6247},
}