title: Multiple organ invasion by viruses: pathological characteristics in three fatal cases of the 2009 pandemic influenza A/H1N1.
abstract: To further understand the pathological characteristics of multiple organ involvement of the 2009 pandemic influenza A/H1N1 infection, tissues of bronchial mucosa, lung, myocardium, gastrocnemius, and liver from 3 patients with fatal A/H1N1 infections were investigated by light microscopy and transmission electron microscopy. In all 3 patients, bronchial mucosa showed necrotizing bronchiolitis, epithelial necrosis and desquamation, and squamous metaplasia, while lung consolidation or fibrosis was identified. Myocardium and gastrocnemius exhibited focal necrosis and fibrosis, surrounded by muscle cells showing features of cell damage. In liver, there was widespread fatty degeneration and necrosis, most often around the central lobular vein and portal area. Viral particles were found in all samples, frequently located in endothelium, epithelium, and muscle cells. The observations demonstrate that in fatal cases of A/H1N1 infection, viruses not only infect the respiratory system, but also engage in multiple organ invasions, causing pathologic changes.
authors.affiliation: Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China. ruyongxin@.tom.com
authors.forename: Yong-xin
authors.initials: YX
authors.lastname: Ru
authors.forename: Yue-chuan
authors.initials: YC
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhao
authors.forename: Shi-xuan
authors.initials: SX
authors.lastname: Zhao
authors.forename: Jing-Ping
authors.initials: JP
authors.lastname: Yang
authors.forename: Hua-Mei
authors.initials: HM
authors.lastname: Zhang
authors.forename: Tian-Xiang
authors.initials: TX
authors.lastname: Pang
mesh_terms: D000328:Adult; D000368:Aged; D001980:Bronchi / Q000473:pathology / Q000821:virology; D001988:Bronchiolitis / Q000473:pathology / Q000821:virology; D002681:China / Q000453:epidemiology; D005234:Fatty Liver / Q000473:pathology / Q000821:virology; D005355:Fibrosis / Q000473:pathology / Q000821:virology; D006321:Heart / Q000821:virology; D054884:Host-Pathogen Interactions; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000235:genetics / Q000302:isolation & purification* / Q000648:ultrastructure; D007251:Influenza, Human / Q000401:mortality / Q000473:pathology* / Q000821:virology; D008171:Lung Diseases / Q000473:pathology / Q000821:virology; D008297:Male; D046529:Microscopy, Electron, Transmission; D009102:Multiple Organ Failure / Q000401:mortality / Q000473:pathology* / Q000821:virology; D018482:Muscle, Skeletal / Q000473:pathology / Q000821:virology; D009206:Myocardium / Q000473:pathology; D009336:Necrosis / Q000473:pathology / Q000821:virology; D058873:Pandemics; D020545:Respiratory Mucosa / Q000648:ultrastructure / Q000821:virology; D015996:Survival Rate