Campylobacter
The genus Campylobacter, (meaning 'twisted bacteria') first discovered in 1963[1], describes Gram-negative, spiral, microaerophilic bacteria. Motile, with either uni- or bi-polar flagella, the organisms have a characteristic spiral/corkscrew appearance (see photo) and are oxidase-positive.[2]Campylobacter jejuni is now recognized as one of the main causes of bacterial foodborne disease in many developed countries.[3] At least a dozen species of Campylobacter have been implicated in human disease, with C. jejuni and C. coli the most common.[2] C. fetus is a cause of spontaneous abortions in cattle and sheep, as well as an opportunistic pathogen in humans.[4]
Genome
The genomes of several Campylobacter spec have been sequenced, providing insights into their mechanisms of pathogenesis.[5] The first Campylobacter genome to be sequenced was C. jejuni, in 2000.[6]
Campylobacter species contain two flagellin genes in tandem for motility, flaA and flaB. These genes undergo intergenic recombination, further contributing to their virulence. [7] Non-motile mutants do not colonize.
Pathogenesis
Campylobacteriosis is an infection by campylobacter.[8] The common routes of transmission are fecal-oral, person-to-person sexual contact, ingestion of contaminated food or water, and the eating of raw meat. It produces an inflammatory, sometimes bloody, diarrhea, periodontitis[9] or dysentery syndrome, mostly including cramps, fever and pain. The infection is usually self-limiting and in most cases, symptomatic Campylobacteriosis treatment by reposition of liquid and electrolyte replacement is enough in human infections. The use of antibiotics, on the other hand, is controversial.
Cause
The sites of tissue injury include the jejunum, the ileum, and the colon. Most strains of C jejuni produce a toxin (cytolethal distending toxin) that hinders the cells from dividing and activating the immune system. This helps the bacteria to evade the immune system and survive for a limited time in the cells. It was thought that a cholera-like enterotoxin was also made, but this appears not to be the case. The organism produces diffuse, bloody, edematous, and exudative enteritis. In a small number of cases, the infection may be associated with hemolytic uremic syndrome and thrombotic thrombocytopenic purpura through a poorly understood mechanism.