title: Systemic distribution of West Nile virus infection: postmortem immunohistochemical study of six cases.
abstract: Rare cases of West Nile virus (WNV)-associated inflammation outside the central nervous system (CNS) have been reported. We evaluated the systemic distribution of WNV in postmortem tissues during encephalitis in six patients using immunohistochemistry. WNV antigens were detected in neurons of CNS (all 6 cases), kidney (4 cases), lungs (2 cases), pancreas (2 cases), thyroid (2 cases), intestine (2 cases), stomach (1 case), esophagus (1 case), bile duct (1 case), skin (1 case), prostate (1 case) and testis (1 case). In systemic organs epithelial cells were infected. In none of the six cases were viral antigens identified in hepatocytes, heart, adrenal gland, nerves, skeletal muscles, bone, vessels and fat. All cases in which viral antigens were identified in systemic organs in addition to CNS were severely immunocompromised transplant recipients. With the exception of testis and brain, most foci of infection were not associated with inflammation. While the absence of inflammation may in part be due to patient immunosuppression or to possible transient nature of any host response, compartmentalization of viral antigen to the luminal region of epithelial cells may sequester WNV from immune recognition. Comparison of our findings with previous reports suggests that patients with WNV encephalitis can have widespread systemic infection.
authors.affiliation: Department of Pathology, University of Pittsburgh Medical Center, Presbyterian Hospital, Pittsburgh, PA 15213, USA. armahh2@upmc.edu
authors.forename: Henry B
authors.initials: HB
authors.lastname: Armah
authors.forename: Guoji
authors.initials: G
authors.lastname: Wang
authors.forename: Bennet I
authors.initials: BI
authors.lastname: Omalu
authors.forename: Robert B
authors.initials: RB
authors.lastname: Tesh
authors.forename: Kymberly A
authors.initials: KA
authors.lastname: Gyure
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: Chute
authors.forename: Roger D
authors.initials: RD
authors.lastname: Smith
authors.forename: Paul
authors.initials: P
authors.lastname: Dulai
authors.forename: Harry V
authors.initials: HV
authors.lastname: Vinters
authors.forename: Bette K
authors.initials: BK
authors.lastname: Kleinschmidt-DeMasters
authors.forename: Clayton A
authors.initials: CA
authors.lastname: Wiley
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000956:Antigens, Viral / Q000276:immunology*; D001344:Autopsy; D001921:Brain / Q000276:immunology / Q000473:pathology / Q000821:virology; D018450:Disease Progression; D004847:Epithelial Cells / Q000276:immunology / Q000473:pathology / Q000821:virology; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D016867:Immunocompromised Host / Q000276:immunology; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D014766:Viremia / Q000473:pathology / Q000503:physiopathology / Q000821:virology; D014781:Viscera / Q000276:immunology / Q000473:pathology / Q000821:virology*; D014901:West Nile Fever / Q000150:complications* / Q000276:immunology / Q000473:pathology; D014902:West Nile virus / Q000276:immunology*
chemical_list: D000956:Antigens, Viral