title: Clinical features and outcomes of influenza infections in lung transplant recipients: a single-season cohort study.
abstract: BACKGROUND
  For lung transplant recipients (LTRs) influenza infections pose a considerable risk for complications. These infections have mainly been described in hospitalized patients. The aim of this study was to describe characteristics of predominantly outpatient-treated influenza infections.
  
  
  METHODS
  We conducted a single-season (2010/2011) retrospective observational study using database information of our cohort. Patients with evidence for respiratory tract infection received empirical oseltamivir and an oral antibiotic, pending results from nasopharyngeal swab analysis. In laboratory-confirmed influenza infection, treatment was continued and serial weekly swabs were performed until virologic results were negative.
  
  
  RESULTS
  We identified 22 infections in 21 of 173 patients followed up; influenza A virus was diagnosed in 13 and influenza B virus in 9 infections. Leading presenting symptoms were cough and rhinorrhea. Oseltamivir was given within 48 h of symptom onset in 13 infections and within 72 h in 21 infections. Prolonged viral shedding (PVS) for ≥ 7 days was detected in 15 infections; median shedding duration for influenza A was 21 days. In univariable analysis, viral load (VL) at diagnosis was associated with extended duration of shedding (P = 0.006). Multivariable analysis confirmed this association. Bronchiolitis obliterans syndrome stage increased in 3 patients at 6-month follow-up.
  
  
  CONCLUSIONS
  In this study, PVS of influenza virus was detected in the majority of LTRs and high VL at diagnosis was predictive for prolonged shedding, which occurred despite extended antiviral therapy.
authors.affiliation: Division of Pulmonology, Zurich University Hospital, Zurich, Switzerland.
authors.forename: M M
authors.initials: MM
authors.lastname: Schuurmans
authors.forename: B D
authors.initials: BD
authors.lastname: Isenring
authors.forename: C
authors.initials: C
authors.lastname: Jungo
authors.forename: J
authors.initials: J
authors.lastname: Boeni
authors.forename: N J
authors.initials: NJ
authors.lastname: Mueller
authors.forename: M
authors.initials: M
authors.lastname: Kohler
authors.forename: C
authors.initials: C
authors.lastname: Benden
mesh_terms: D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D009980:Influenza A virus / Q000502:physiology; D007251:Influenza, Human / Q000188:drug therapy / Q000473:pathology*; D016040:Lung Transplantation; D008297:Male; D008875:Middle Aged; D053139:Oseltamivir / Q000627:therapeutic use*; D012189:Retrospective Studies; D012621:Seasons; D016896:Treatment Outcome; D019562:Viral Load; D017201:Virus Shedding
chemical_list: D000998:Antiviral Agents; D053139:Oseltamivir
keywords: infection; influenza; lung transplantation; outpatient; prolonged viral shedding; viral load