{{Short description|Positive indicator of rabies infection}} thumb|Histopathology of Negri bodies in rabies encephalitis. [[Image:Rabies Virus EM PHIL 1876.JPG|thumb|250px|Micrograph with numerous rabies virions (small dark-grey rod-like particles) and Negri bodies, larger pathognomonic cellular inclusion bodies of rabies infection.]]
'''Negri bodies''' are eosinophilic, sharply outlined, pathognomonic inclusion bodies (2–10 μm in diameter) found in the cytoplasm of certain nerve cells containing the virus of rabies, especially in pyramidal cells<ref name=":0">{{Cite web|url=https://www.sketchymedical.com/sections/viruses-2-3-rhabdovirus|title=2.3 Rhabdovirus|last=Sketchy Group, LLC|website=www.sketchymedical.com|language=en|access-date=2017-04-12|archive-url=https://web.archive.org/web/20170413234842/https://www.sketchymedical.com/sections/viruses%2D2%2D3%2Drhabdovirus|archive-date=2017-04-13|url-status=dead}}</ref> within Ammon's horn of the hippocampus. They are also often found in the Purkinje cells<ref name=":0" /> of the cerebellar cortex from postmortem brain samples of rabies victims. They consist of ribonuclear proteins produced by the virus.<ref>{{cite journal|last1=Lahaye|first1=Xavier|last2=Vidy|first2=Aurore|last3=Pomier|first3=Carole|last4=Obiang|first4=Linda|last5=Harper|first5=Francis|last6=Gaudin|first6=Yves|last7=Blondel|first7=Danielle|title=Functional Characterization of Negri Bodies (NBs) in Rabies Virus-Infected Cells: Evidence that NBs Are Sites of Viral Transcription and Replication|journal=Journal of Virology|date=15 August 2009|volume=83|issue=16|pages=7948–7958|doi=10.1128/JVI.00554-09|pmid=19494013|language=en|issn=0022-538X|pmc=2715764}}</ref>
They are named for Adelchi Negri.<ref>{{WhoNamedIt|synd|2491}}</ref>
==History and significance== Adelchi Negri, an assistant pathologist working in the laboratory of Camillo Golgi, observed these inclusions in rabbits and dogs with rabies. These findings were presented in 1903 at a meeting of the Società Medico-Chirurgica of Pavia. The American pathologist Anna Wessels Williams made the same discovery,<ref>{{Cite web|url=https://cfmedicine.nlm.nih.gov/physicians/biography_331.html|title=Changing the Face of Medicine|website=NCBI}}</ref> but because Negri published his results<ref>{{Cite journal|last=Negri|first=Adelchi|date=1904|title=Contributo allo studio dell'eziologia della rabbia|journal=Bollettino della Società Medico-chirurgica di Pavia|volume=2|pages=88–115}}</ref> first, the bodies bear his name.
Negri was convinced the inclusions were a parasitic protozoon and the etiologic agent of rabies. Later that same year, however, Paul Remlinger and Rifat-Bey Frasheri in Constantinople and, separately, Alfonso di Vestea in Naples showed that the etiologic agent of rabies is a filterable virus. Negri continued until 1909 to try to prove that the intraneuronal inclusions named after him corresponded to steps in the developmental cycle of a protozoan.
In spite of his incorrect etiologic hypothesis, Negri's discovery represented a breakthrough in the rapid diagnosis of rabies, and the detection of Negri bodies, using a method developed by Anna Wessels Williams, remained the primary way to detect rabies for the next thirty years.<ref>{{cite journal |last1=Henry |first1=Ronnie |last2=Murphy |first2=Frederick R. |date=2017 |title=Etymologia: Negri Bodies |journal= Emerg Infect Dis |volume=23 |issue=9 |pages=1461 |doi=10.3201/eid2309.ET2309 |quote=citing public domain text from the CDC |pmc=5572856 }}</ref>
==References== {{Reflist}}
==External links== * [http://pathmicro.med.sc.edu/virol/rabies.htm Slide at pathmicro.med.sc.edu – see bottom] * [https://www.youtube.com/watch?v=NP5CYphae5Y See pathology video of Negri bodies]
{{Infectious blood tests}}
{{DEFAULTSORT:Negri Bodies}} Category:Histopathology Category:Rabies Category:Hippocampus (brain) Category:Neuropathology