title: The role of bacteriologic infection in the etiology of nasolacrimal duct obstruction.
abstract: BACKGROUND
  In patients with nasolacrimal duct obstruction, the inflammation and fibrosis may be secondary to coexisting infectious colonization within the lumen of the lacrimal sac. We examined the bacterial flora within the lacrimal sac at the sac-duct junction to explore the possibility of a primary bacteriologic etiology of the inflammatory response.
  
  
  METHODS
  The study included 114 consecutive patients (132 sides) with epiphora undergoing routine external dacryocystorhinostomy (DCR) at a tertiary care hospital in Toronto between November 1999 and April 2000. A lacrimal sac tissue biopsy specimen was acquired intraoperatively from the inferior posterior lacrimal sac near the sac-duct junction. Microbiologic analysis was carried out to determine the presence and identification of infectious organisms.
  
  
  RESULTS
  Culture gave positive results in 51 patients (44.7%) (41.7% of specimens). A total of 65 isolates were cultured, of which 78.5% were gram-positive bacteria and 21.5% gram-negative bacteria. Of the gram-positive organisms 76.5% were Staphylococcus sp. The presence of a positive culture result was independent of a history of dacryocystitis or the presence of a mucocele.
  
  
  CONCLUSIONS
  Using direct biopsy methods, we found culture-positive lacrimal sac specimens in a large proportion of patients undergoing DCR surgery. These organisms were found to be present in patients with and without a history of infection.
authors.affiliation: Ophthalmic Plastic Surgery Service, Mount Sinai Hospital, University of Toronto, Toronto, Ont.
authors.forename: D
authors.initials: D
authors.lastname: DeAngelis
authors.forename: J
authors.initials: J
authors.lastname: Hurwitz
authors.forename: T
authors.initials: T
authors.lastname: Mazzulli
mesh_terms: D015373:Bacterial Typing Techniques; D003608:Dacryocystorhinostomy; D015818:Eye Infections, Bacterial / Q000382:microbiology* / Q000601:surgery; D006090:Gram-Negative Bacteria / Q000145:classification / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000145:classification / Q000302:isolation & purification*; D006801:Humans; D007767:Lacrimal Duct Obstruction / Q000382:microbiology*; D009301:Nasolacrimal Duct / Q000382:microbiology* / Q000601:surgery; D013666:Tears / Q000382:microbiology