Shigella: Difference between revisions

Jump to navigation Jump to search
m (Robot: Automated text replacement (-{{SIB}} +, -{{EH}} +, -{{EJ}} +, -{{Editor Help}} +, -{{Editor Join}} +))
 
Line 25: Line 25:


'''''Shigella''''' is a [[genus]] of [[Gram-negative]], [[Motility|non-motile]], [[Endospore|non-spore forming]] rod-shaped [[bacterium|bacteria]] closely related to ''[[Escherichia coli]]'' and ''[[Salmonella]]''. The causative agent of human [[shigellosis]], ''Shigella'' also cause disease in other [[primate]]s, but not in other mammals.<ref>{{cite book | author = Ryan KJ, Ray CG (editors) | title = Sherris Medical Microbiology | edition = 4th ed. | publisher = McGraw Hill | year = 2004 |isbn = 0-8385-8529-9 }}</ref>
'''''Shigella''''' is a [[genus]] of [[Gram-negative]], [[Motility|non-motile]], [[Endospore|non-spore forming]] rod-shaped [[bacterium|bacteria]] closely related to ''[[Escherichia coli]]'' and ''[[Salmonella]]''. The causative agent of human [[shigellosis]], ''Shigella'' also cause disease in other [[primate]]s, but not in other mammals.<ref>{{cite book | author = Ryan KJ, Ray CG (editors) | title = Sherris Medical Microbiology | edition = 4th ed. | publisher = McGraw Hill | year = 2004 |isbn = 0-8385-8529-9 }}</ref>
== Classification ==
''Shigella'' species are classified by four serogroups:
* Serogroup ''A'': ''[[Shigella dysenteriae|S. dysenteriae]]'' (12 [[serotype]]s)
* Serogroup ''B'': ''[[Shigella flexneri|S. flexneri]]'' (6 serotypes)
* Serogroup ''C'': ''[[Shigella boydii|S. boydii]]'' (23 serotypes)
* Serogroup ''D'': ''[[Shigella sonnei|S. sonnei]]'' (1 serotype)
Group ''A''–''C'' are physiologically similar; ''S. sonnei'' (group ''D'') can be differentiated on the basis of biochemical metabolism assays.<ref>{{cite book | author =  Hale TL, Keusch GT | title = Shigella: Structure, Classification, and Antigenic Types. ''in:'' Baron's Medical Microbiology ''(Baron S ''et al'', eds.)| edition = 4th ed. | publisher = Univ of Texas Medical Branch | year = 1996 | url = http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mmed.section.1269 | isbn = 0-9631172-1-1 }}</ref>


== Pathogenesis ==
== Pathogenesis ==

Revision as of 21:18, 5 April 2015

Shigella
Photomicrograph of Shigella sp. in a stool specimen
Photomicrograph of Shigella sp. in a stool specimen
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Gamma Proteobacteria
Order: Enterobacteriales
Family: Enterobacteriaceae
Genus: Shigella
Castellani & Chalmers 1919
Species

S. boydii
S. dysenteriae
S. flexneri
S. sonnei

WikiDoc Resources for Shigella

Articles

Most recent articles on Shigella

Most cited articles on Shigella

Review articles on Shigella

Articles on Shigella in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Shigella

Images of Shigella

Photos of Shigella

Podcasts & MP3s on Shigella

Videos on Shigella

Evidence Based Medicine

Cochrane Collaboration on Shigella

Bandolier on Shigella

TRIP on Shigella

Clinical Trials

Ongoing Trials on Shigella at Clinical Trials.gov

Trial results on Shigella

Clinical Trials on Shigella at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Shigella

NICE Guidance on Shigella

NHS PRODIGY Guidance

FDA on Shigella

CDC on Shigella

Books

Books on Shigella

News

Shigella in the news

Be alerted to news on Shigella

News trends on Shigella

Commentary

Blogs on Shigella

Definitions

Definitions of Shigella

Patient Resources / Community

Patient resources on Shigella

Discussion groups on Shigella

Patient Handouts on Shigella

Directions to Hospitals Treating Shigella

Risk calculators and risk factors for Shigella

Healthcare Provider Resources

Symptoms of Shigella

Causes & Risk Factors for Shigella

Diagnostic studies for Shigella

Treatment of Shigella

Continuing Medical Education (CME)

CME Programs on Shigella

International

Shigella en Espanol

Shigella en Francais

Business

Shigella in the Marketplace

Patents on Shigella

Experimental / Informatics

List of terms related to Shigella


This article is about the bacteria. For the disease, see shigellosis

Shigella is a genus of Gram-negative, non-motile, non-spore forming rod-shaped bacteria closely related to Escherichia coli and Salmonella. The causative agent of human shigellosis, Shigella also cause disease in other primates, but not in other mammals.[1]

Pathogenesis

Shigella infection is typically via ingestion (fecal–oral contamination); depending on age and condition of the host as few as ten bacterial cells can be enough to cause an infection. Shigella cause dysentery that results in the destruction of the epithelial cells of the intestinal mucosa in the cecum and rectum. Some strains produce enterotoxin and Shiga toxin, similar to the verotoxin of E. coli O157:H7.[2] Both Shiga toxin and verotoxin are associated with causing hemolytic uremic syndrome.

Shigella invade the host through epithelial cells of the small intestine. Using a Type III secretion system acting as a biological syringe, the bacterium injects Ipa protein into cell, triggering bacterial invasion, and the subsequently lysis of vacuolar membranes. It utilizes a mechanism for its motility by which its IcsA triggers actin polymerization in the host cell in a "rocket" propulsion fashion for cell-to-cell spread.

The most common symptoms are diarrhea, fever, nausea, vomiting, stomach cramps, and straining to have a bowel movement. The stool may contain blood, mucus, or pus (e.g. dysentery). In rare cases, young children may have seizures. Symptoms can take as long as a week to show up, but most often begin two to four days after ingestion. Symptoms usually last for several days, but can last for weeks. Shigella is implicated as one of the pathogenic causes of reactive arthritis worldwide.[3]

Severe dysentery can be treated with ampicillin, TMP-SMX, or fluoroquinolones such as ciprofloxacin.

External Links

References

  1. Ryan KJ, Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed. ed.). McGraw Hill. ISBN 0-8385-8529-9.
  2. Hale TL, Keusch GT (1996). Shigella. in: Baron's Medical Microbiology (Baron S et al, eds.) (4th ed. ed.). Univ of Texas Medical Branch. ISBN 0-9631172-1-1.
  3. Hill Gaston JS, Lillicrap MS (2003). "Arthritis associated with enteric infection". Best practice & research. Clinical rheumatology. 17 (2): 219–39. PMID 12787523.

ca:Shigel·la da:Shigella de:Shigella fa:شیگلا ko:이질균 it:Shigella he:Shigella nl:Shigella no:Shigella sv:Shigella uk:Shigella


Template:WikiDoc Sources