title: Autopsy findings in eight patients with fatal H1N1 influenza.
abstract: A novel H1N1 influenza A virus emerged in April 2009, and rapidly reached pandemic proportions. We report a retrospective observational case study of pathologic findings in 8 patients with fatal novel H1N1 infection at the University of Michigan Health Systems (Ann Arbor) compared with 8 age-, sex-, body mass index-, and treatment-matched control subjects. Diffuse alveolar damage (DAD) in acute and organizing phases affected all patients with influenza and was accompanied by acute bronchopneumonia in 6 patients. Organizing DAD with established fibrosis was present in 1 patient with preexisting granulomatous lung disease. Only 50% of control subjects had DAD. Peripheral pulmonary vascular thrombosis occurred in 5 of 8 patients with influenza and 3 of 8 control subjects. Cytophagocytosis was seen in all influenza-related cases. The autopsy findings in our patients with novel H1N1 influenza resemble other influenza virus infections with the exception of prominent thrombosis and hemophagocytosis. The possibility of hemophagocytic syndrome should be investigated in severely ill patients with H1N1 infection.
authors.affiliation: Dept of Pathology, University of Michigan, Ann Arbor, 48109-5602, USA.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Harms
authors.forename: Lindsay A
authors.initials: LA
authors.lastname: Schmidt
authors.forename: Lauren B
authors.initials: LB
authors.lastname: Smith
authors.forename: Duane W
authors.initials: DW
authors.lastname: Newton
authors.forename: Maria A
authors.initials: MA
authors.lastname: Pletneva
authors.forename: Laura L
authors.initials: LL
authors.lastname: Walters
authors.forename: Scott A
authors.initials: SA
authors.lastname: Tomlins
authors.forename: Amanda
authors.initials: A
authors.lastname: Fisher-Hubbard
authors.forename: Lena M
authors.initials: LM
authors.lastname: Napolitano
authors.forename: Pauline K
authors.initials: PK
authors.lastname: Park
authors.forename: Mila
authors.initials: M
authors.lastname: Blaivas
authors.forename: Joseph
authors.initials: J
authors.lastname: Fantone
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Myers
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Jentzen
mesh_terms: D000328:Adult; D001996:Bronchopneumonia / Q000473:pathology / Q000821:virology; D004279:DNA, Viral / Q000032:analysis; D017809:Fatal Outcome; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000302:isolation & purification*; D007251:Influenza, Human / Q000473:pathology* / Q000821:virology; D008168:Lung / Q000473:pathology* / Q000821:virology; D051359:Lymphohistiocytosis, Hemophagocytic / Q000473:pathology / Q000821:virology; D008297:Male; D008875:Middle Aged; D011650:Pulmonary Alveoli / Q000473:pathology / Q000821:virology; D011655:Pulmonary Embolism / Q000473:pathology / Q000821:virology; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D004279:DNA, Viral