Reviewed for currency January 14, 2021 Whipple disease (WD) is a rare systemic infectious disorder caused by the actinomycete Tropheryma whipplei. This chronic disease, first described by Whipple as “intestinal lipodystrophy,” preferentially affects middle-aged white men, who may present with…
Erysipelothrix rhusiopathiae is a thin, pleomorphic, nonsporulating gram-positive rod. First isolated from mice by Robert Koch in 1878 and from swine by Louis Pasteur in 1882, it was established as the etiologic agent of swine erysipelas in 1886 by Löffler…
Microbiology Bacteria of the genus Bacillus are well adapted to their normal environment of soil. This includes Bacillus anthracis, discussed elsewhere in this text (see Chapter 207 ). These gram-positive or gram-variable, aerobic or facultatively anaerobic, rod-shaped bacilli have rounded…
Anthrax has never been a cause of the massive loss of life associated with cholera, plague, or smallpox, but it has played a prominent role in the history of infectious diseases. While much of the industrialized world is focused on…
Definition Listeria monocytogenes is a gram-positive bacillus and zoonotic and foodborne pathogen found worldwide that causes listeriosis. Listeriosis spans the clinical spectrum from self-limited febrile gastroenteritis in immunocompetent people to more severe and invasive disease that mostly affects pregnant women,…
Coryneform Bacteria Other Than Corynebacterium diphtheriae Corynebacterium was proposed as a genus by Lehmann and Neumann in 1896, who derived the name from the Greek koryne, which means “club,” and bacterion, meaning “little rod.” The coryneforms are a diverse group…
A primary series of vaccination with diphtheria toxoid affords protective immunity in children and adults. To counter the effect of waning immunity, booster doses should be administered every 10 years to older children and adults who have completed the primary…
The Streptococcus anginosus (milleri) group is a subgroup within the viridans-group streptococci that includes three separate streptococcal species: S. anginosus, S. constellatus, and S. intermedius. These viridans-group streptococci are part of the normal flora of the human oropharynx and urogenital…
Overview The viridans group streptococci (VGS) are a diverse group of organisms and are the predominant microbiota in the oropharynx and gastrointestinal (GI) tract. The viridans streptococci cause a significant percentage of all cases of infective endocarditis (IE). Streptococcus mutans…
Reviewed for currency January 14, 2021 Historical Perspective Group B streptococci (GBS; Streptococcus agalactiae ) were reported as human pathogens in 1938 by Fry, who described three cases of fatal puerperal sepsis. Infections in humans were reported infrequently until the…