title: The influence of high-efficiency particulate air filtration on mortality and fungal infection among highly immunosuppressed patients: a systematic review.
abstract: BACKGROUND
  Patients with hematological malignancies who are treated with intensive chemotherapy or who receive bone marrow transplants are exposed to an increased risk of developing nosocomial fungal infections. The aim of this systematic review was to compare the effectiveness of high-efficiency particulate air (HEPA) filtration with that of non-HEPA filtration in decreasing the rates of mortality and fungal infection among patients with diagnosed hematological malignancies and neutropenia or among patients with bone marrow transplants.
  
  
  METHODS
  Articles identified in a Medline search, guidelines, and books, as well as the bibliographies of review articles, monographs, and the articles identified by Medline, were researched. Randomized trials and observational studies comparing HEPA filtration with conventional room ventilation were selected for inclusion in the present review.
  
  
  RESULTS
  Sixteen trials (9 with death as an outcome and 10 with fungal infection as an outcome) that compared HEPA filtration with non-HEPA filtration were selected for meta-analyses. We discovered no significant advantages of HEPA filtration in the prevention of death among patients with hematological malignancies with severe neutropenia in randomized controlled trials (RCTs; relative risk [RR], 0.86 [95% confidence interval {CI}, 0.65-1.14]) and in studies of a lower standard (non-RCTs; RR, 0.87 [95% CI, 0.60-1.25]).
  
  
  CONCLUSIONS
  The placement in protected areas of patients with hematological malignancies with severe neutropenia or patients with bone marrow transplants appears to be beneficial, but no definitive conclusion could be drawn from the data available.
authors.affiliation: Institute of Hygiene and Environmental Medicine, Charité-University Medicine Berlin, Berlin, Germany. tim.eckmanns@charite.de
authors.forename: Tim
authors.initials: T
authors.lastname: Eckmanns
authors.forename: Henning
authors.initials: H
authors.lastname: Rüden
authors.forename: Petra
authors.initials: P
authors.lastname: Gastmeier
mesh_terms: D000391:Air Microbiology; D002487:Centers for Disease Control and Prevention, U.S.; D003428:Cross Infection / Q000150:complications / Q000401:mortality / Q000517:prevention & control*; D016469:Fungemia / Q000150:complications / Q000401:mortality / Q000517:prevention & control*; D006801:Humans; D016867:Immunocompromised Host; D017053:Infection Control / Q000592:standards; D009894:Opportunistic Infections / Q000150:complications / Q000401:mortality / Q000517:prevention & control*; D010356:Patient Isolation; D017410:Practice Guidelines as Topic; D016032:Randomized Controlled Trials as Topic; D014481:United States; D014691:Ventilation / Q000295:instrumentation