![]() ![]() Watery diarrhea, hemorrhagic colitis, hemolytic-uremic syndromeįood-borne and water-borne outbreaks in developed countries Pili, heat-labile and heat-stable enterotoxinsįluid replacement fluoroquinolone or rifaximin can be used alone or in combination with loperamideīundle-forming pilus, attaching and effacing effect ![]() coliĬhildhood diarrhea in developing countries traveler's diarrhea Table 1 Clinical, Epidemiologic, Pathogenetic, and Therapeutic Aspects of Infection with Various Pathotypes of E. 3,4 It is not known what roles the overwhelming majority of these genes play in the biology of the organism or in the pathogenesis of infections. For example, a strain isolated from a woman with pyelonephritis, a strain isolated from a child with hemorrhagic colitis, and a laboratory strain originally isolated from an asymptomatic volunteer share only 39% of their genes in contrast, 47% of the total number of genes in the three strains is unique to one strain only. coli, which are so alike in most characteristics that they could easily be regarded as identical in clinical microbiology laboratories, are remarkably different in genetic content. With the advent of genomic sequencing, it has become evident that different strains of E. coli that causes a particular clinical syndrome by a recognized pathogenic mechanism may be referred to as a pathotype. coli to cause a variety of clinical syndromes by a plethora of mechanisms is entirely dependent upon unique virulence attributes that are encoded by distinct sets of virulence genes. coli, 2 but because of historical and clinical considerations, they are often discussed separately. In fact, the organisms that are commonly referred to as Shigella are actually members of the species E. Thus, it is not surprising that this species has the ability to cause a diverse array of infectious diseases. 1 Ample time for diversifying selection and a prodigious capacity for genetic exchange have fostered a tremendous degree of genetic diversity in E. coliand Salmonelladiverged from a common ancestor about 100 million years ago.Several virulence factors are shared by most members of the species these include the ability to produce a highly reactive lipopolysaccharide in the cell wall, the ability to produce type 1 mannose-binding fimbriae, and, in many strains, the ability to produce an antiphagocytic capsule and to sequester iron. coli'sability to ferment lactose and to produce indole and its inability to hydrolyze urea. ![]() coli, the most common facultative anaerobe in the human intestine, is distinguished from other members of the family Enterobacteriaceae primarily on the basis of E.They cause a variety of diseases, including diarrhea, urinary tract infections (UTIs), and nosocomial infections. They are oxidase negative and catalase positive and are capable of reducing nitrate to nitrite. Many Enterobacteriaceae species reside principally in the gastrointestinal tract of vertebrates, though some are found primarily in the environment. These organisms are often motile because of the presence of peritrichous flagella (i.e., flagella that are distributed around the entire cell). The family Enterobacteriaceae comprises facultative anaerobic gram-negative bacilli that ferment sugars. Infections caused by Salmonella, Shigella, and Yersinia are described elsewhere. This chapter describes infections caused by Escherichia coli and related members of the family Enterobacteriaceae, excluding genera that principally cause enteric infections. The author has no commercial relationships with manufacturers of products or providers of services discussed in this chapter. ACP medicine, 3rd Edition Infectious Disease Infections Due to Escherichia Coli and Other Enteric Gram-Negative Bacilliġ Professor of Medicine, Professor of Microbiology and Immunology, and Head, Division of Infectious Diseases, University of Maryland School of Medicine ![]()
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