title: Eubacterial PCR for bacterial detection and identification in 100 acute postcataract surgery endophthalmitis.
abstract: OBJECTIVE
  To evaluate eubacterial PCR compared with conventional cultures for detection and identification of bacterial agents in ocular samples from patients with acute postcataract endophthalmitis.
  
  
  METHODS
  Broad-range eubacterial PCR amplification was used, followed by direct DNA sequencing in ocular samples (aqueous humor, vitreous samples from tap or vitrectomy) from 100 consecutive patients presenting with acute postcataract endophthalmitis. Bacterial cultures were performed on the same ocular samples by using traditional methods (brain-heart infusion broth).
  
  
  RESULTS
  At the time of admission, the detection rate was not significantly different between cultures and PCR (38.2% for cultures versus 34.6% for PCR in aqueous humor samples; 54% versus 57% in vitreous from a vitreous tap). In contrast, in the vitreous obtained from vitrectomy, after intravitreous injection of antibiotics, PCR detected bacteria in 70% of the cases, compared with 9% in cultures. By combining PCR and cultures, bacterial identification was obtained in 47% of aqueous humor samples at admission, in 68% of vitreous samples from a vitreous tap at admission, and in 72% of vitreous samples from pars plana vitrectomy. Gram-positive bacteria predominated (94.3%). The concordance between cultures and PCR was 100%. The contamination rate was 2%.
  
  
  CONCLUSIONS
  Cultures and eubacterial PCR are complementary techniques for bacterial identification in eyes with acute postcataract endophthalmitis. PCR technique was needed for identification of the involved microbial pathogen in 25% of all the cases. Eubacterial PCR is more effective than cultures in detecting bacteria in vitreous samples from patients with previous intravitreous administration of antibiotics.
authors.affiliation: Department of Ophthalmology, University Hospital Center (CHU) de Grenoble, Université Joseph Fourier, Grenoble, France. cchiquet@chu-grenoble.fr
authors.forename: Christophe
authors.initials: C
authors.lastname: Chiquet
authors.forename: Pierre-Loic
authors.initials: PL
authors.lastname: Cornut
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Benito
authors.forename: Gilles
authors.initials: G
authors.lastname: Thuret
authors.forename: Max
authors.initials: M
authors.lastname: Maurin
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Lafontaine
authors.forename: Andre
authors.initials: A
authors.lastname: Pechinot
authors.forename: Karine
authors.initials: K
authors.lastname: Palombi
authors.forename: Gerard
authors.initials: G
authors.lastname: Lina
authors.forename: Alain
authors.initials: A
authors.lastname: Bron
authors.forename: Philippe
authors.initials: P
authors.lastname: Denis
authors.forename: Anne
authors.initials: A
authors.lastname: Carricajo
authors.forename: Catherine
authors.initials: C
authors.lastname: Creuzot
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Romanet
authors.forename: Francois
authors.initials: F
authors.lastname: Vandenesch
mesh_terms: D000208:Acute Disease; D000368:Aged; D001082:Aqueous Humor / Q000382:microbiology; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification*; D001431:Bacteriological Techniques; D004269:DNA, Bacterial / Q000032:analysis*; D009877:Endophthalmitis / Q000382:microbiology*; D015818:Eye Infections, Bacterial / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D018918:Phacoemulsification; D016133:Polymerase Chain Reaction / Q000379:methods*; D011183:Postoperative Complications; D011446:Prospective Studies; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014822:Vitreous Body / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S