title: H275Y mutant pandemic (H1N1) 2009 virus in immunocompromised patients.
abstract: Most oseltamivir-resistant pandemic (H1N1) 2009 viruses have been isolated from immunocompromised patients. To describe the clinical features, treatment, outcomes, and virologic data associated with infection from pandemic (H1N1) 2009 virus with H275Y mutation in immunocompromised patients, we retrospectively identified 49 hematology-oncology patients infected with pandemic (H1N1) 2009 virus. Samples from 33 of those patients were tested for H275Y genotype by allele-specific real-time PCR. Of the 8 patients in whom H275Y mutations was identified, 1 had severe pneumonia; 3 had mild pneumonia with prolonged virus shedding; and 4 had upper respiratory tract infection, of whom 3 had prolonged virus shedding. All patients had received oseltamivir before the H275Y mutation was detected; 1 had received antiviral prophylaxis. Three patients excreted resistant virus for >60 days. Emergence of oseltamivir resistance is frequent in immunocompromised patients infected with pandemic (H1N1) 2009 virus and can be associated with a wide range of clinical disease and viral kinetics.
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Renaud
authors.forename: Alexandre A
authors.initials: AA
authors.lastname: Boudreault
authors.forename: Jane
authors.initials: J
authors.lastname: Kuypers
authors.forename: Kathryn H
authors.initials: KH
authors.lastname: Lofy
authors.forename: Lawrence
authors.initials: L
authors.lastname: Corey
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Boeckh
authors.forename: Janet A
authors.initials: JA
authors.lastname: Englund
mesh_terms: D000293:Adolescent; D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use; D002648:Child; D024882:Drug Resistance, Viral / Q000235:genetics; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D053118:Influenza A Virus, H1N1 Subtype / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D007251:Influenza, Human / Q000150:complications / Q000188:drug therapy / Q000821:virology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012141:Respiratory Tract Infections / Q000209:etiology / Q000821:virology; D055815:Young Adult
chemical_list: D000998:Antiviral Agents