title: Intracellular residency is frequently associated with recurrent Staphylococcus aureus rhinosinusitis.
abstract: OBJECTIVE
  The prevalence of intracellular Staphylococcus aureus organisms in the nasal mucosa of patients with recurrent infectious rhinosinusitis episodes was studied.
  
  
  METHODS
  Twenty-seven consecutive adult patients who failed medical management of chronic rhinosinusitis (CRS) of multiple origins, associated or not with nasal polyposis, were consecutively enrolled for endonasal sinus surgery (including partial middle turbinectomy, middle antrostomy, ethmoidectomy, sphenoidotomy) and followed for a 12-month post-operative period.
  
  
  RESULTS
  Seventeen of these patients showed the presence of intracellular S. aureus as detected by confocal laser scan immunofluorescence microscopy in epithelial cells of surgical intranasal biopsy specimens. Nine of the patients with and two without intracellular bacteria yielded S. aureus in endoscopically guided cultures of middle meatus secretions, despite the recent administration of prophylactic antibiotics. Eleven of the 17 patients with intracellular S. aureus relapsed for rhinosinusitis within the 12-month follow-up period. Molecular typing of sequential S. aureus isolates demonstrated the persistence of unique patient-specific S. aureus clonotypes in nine of the patients with intracellular bacteria during the 12-month follow-up.
  
  
  CONCLUSIONS
  The presence of intracellular S. aureus in epithelial cells of the nasal mucosa is a significant risk factor for recurrent episodes of rhinosinusitis due to persistent bacterial clonotypes, which appear refractory to antimicrobial and surgical therapy.
authors.affiliation: Rhinology - Olfactology Unit, Department of Otorhinolaryngology/Head and Neck Surgery, Geneva University Hospital, Geneva, Switzerland.
authors.forename: I
authors.initials: I
authors.lastname: Plouin-Gaudon
authors.forename: S
authors.initials: S
authors.lastname: Clement
authors.forename: E
authors.initials: E
authors.lastname: Huggler
authors.forename: C
authors.initials: C
authors.lastname: Chaponnier
authors.forename: P
authors.initials: P
authors.lastname: François
authors.forename: D
authors.initials: D
authors.lastname: Lew
authors.forename: J
authors.initials: J
authors.lastname: Schrenzel
authors.forename: P
authors.initials: P
authors.lastname: Vaudaux
authors.forename: J S
authors.initials: JS
authors.lastname: Lacroix
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002353:Carrier State; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000382:microbiology*; D011446:Prospective Studies; D012008:Recurrence; D012220:Rhinitis / Q000382:microbiology* / Q000601:surgery*; D012307:Risk Factors; D012852:Sinusitis / Q000382:microbiology* / Q000601:surgery*; D013203:Staphylococcal Infections / Q000150:complications* / Q000601:surgery*; D013211:Staphylococcus aureus / Q000302:isolation & purification*; D016896:Treatment Outcome