![]() dysenteriae is the most pathogenic species, with a fatality rate up to 20%, whereas S. Severity of infection depends on the host, dose, and serotype ( 2). Infections are usually self-limiting, but can become life-threatening in immunocompromised patients or if not properly treated. Virulence of Shigella is temperature-regulated, as organisms are able to invade HeLa cells at 37☌, and cannot do so in vitro at 30☌ ( 12). dysenteriae that can also cause other neurotoxic effects). flexneri ( 9, 10), severe dehydration, intestinal perforation, toxic mega colon, bacteremia, toxaemia ( 11), septicaemia, seizures, toxic encephalopathy with headache and alterations of consciousness, septic shock and convulsions (very rare) ( 4), and haemolytic uremic syndrome, which have been linked to Shiga toxin (a potent cytotoxin produced by S. Further complications include Reiter’s syndrome which has been associated with S. Infection may be mild and asymptomatic, but it is most commonly characterized by acute intestinal infections upon ingestion, resulting in mild watery diarrhea to severe inflammatory bacillary dysentery or shigellosis, manifested by severe abdominal cramps, nausea and vomiting, fever, tenesmus, anorexia, and stool containing blood and mucus ( 1, 2, 8). PATHOGENICITY/TOXICITY: Ingested pathogens can survive gastric acidity and cause illness by infecting the colonic mucosa and multiplying in the colonic epithelial cells, and spreading laterally to adjacent cells ( 5- 7). dysenteriae is considered the most virulent, and can produce a potent cytotoxin known as Shigatoxin ( 4). Different serogroups, considered as species, can be differentiated by their biochemical properties, phage or colicin susceptibility, and polyvanlent antisera can detect specific polysaccharide antigens ( 2, 3). They are non-motile, non-encapsulated, and facultative anaerobes that do not ferment lactose, or do so slowly. ![]() sonnei, shigellosis, and bacillary dysentery.ĬHARACTERISTICS: Shigella spp., of the Enterobacteriaceae family, are gram-negative rod-shaped pathogenic bacteria ( 1). ![]() SYNONYM OR CROSS REFERENCE: Serogroup A: S. PATHOGEN SAFETY DATA SHEET - INFECTIOUS SUBSTANCES SECTION I - INFECTIOUS AGENT ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |