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Bacillary dysentery is a type of dysentery, and is a severe form of shigellosis. Bacillary dysentery is associated with species of bacteria from the Enterobacteriaceae family. The term is usually restricted to ''Shigella'' infections. Shigellosis is caused by one of several types of ''Shigella'' bacteria. Three species are associated with bacillary dysentery: ''Shigella sonnei, Shigella flexneri'' and ''Shigella dysenteriae''. A study in China indicated that ''Shigella flexneri'' 2a was the most common serotype. Salmonellosis caused by ''Salmonella enterica'' (serovar ''Typhimurium'') has also been described as a cause of bacillary dysentery, though this definition is less common. It is sometimes listed as an explicit differential diagnosis of bacillary dysentery, as opposed to a cause. Bacillary dysentery should not be confused with diarrhea caused by a bacterial infection. One characteristic of bacillary dysentery is blood in stool, which is the result of invasion of the mucosa by the pathogen. ==Pathogenesis== Transmission is fecal-oral and is remarkable for the small number of organisms that may cause disease (10 ingested organisms cause illness in 10% of volunteers, and 500 organisms cause disease in 50% of volunteers). ''Shigella'' bacteria invade the intestinal mucosal cells but do not usually go beyond the lamina propria. Dysentery is caused when the bacteria escape the epithelial cell phagolysosome, multiply within the cytoplasm, and destroy host cells. Shiga toxin causes hemorrhagic colitis and hemolytic-uremic syndrome by damaging endothelial cells in the microvasculature of the colon and the glomeruli, respectively. In addition, chronic arthritis secondary to ''S. flexneri'' infection, called reactive arthritis, may be caused by a bacterial antigen; the occurrence of this syndrome is strongly linked to HLA-B27 genotype, but the immunologic basis of this reaction is not understood. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「bacillary dysentery」の詳細全文を読む スポンサード リンク
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