Tags: Cellulitis

Leishmania

The genera Leishmania and Trypanosoma are members of the family Trypanosomatidae. These protozoans cause diseases with widely varied clinical presentations as well as geographic distributions, including leishmaniasis, American trypanosomiasis (Chagas’ disease), and African trypanosomiasis (sleeping sickness).

Borrelia & Leptospira Species

The syndrome of relapsing fever consists of two clinical entities: epidemic relapsing fever caused by Borrelia recurrentis (LBRF) and transmitted by the human body louse and endemic relapsing fever caused by Borrelia spp. (TBRF) and transmitted by arthropods (Table 1). A. Epidemiology. 1. Louse-borne epidemic relapsing fever (LBRF).

Actinomycetes

Originally thought to be fungi due to their hyphae-like appearance, they are now recognized as bacteria based on their cell wall components, reproduction by fission without sporulation or budding, inhibition by antibacterial agents, and molecular phylogenetic analysis. The actinomycete chromosomes contain a high content of guanosine and cytosine.

Nocardia

Nocardia spp. are strictly aerobic, ubiquitous soil-dwelling organisms that are largely responsible for the decomposition of organic plant material. Infection usually occurs via inhalation of these organisms in airborne dust particles, leading to pulmonary disease.

Yersiniosis

Conditions that are associated with increased risk for Yersinia spp. infections (yersiniosis) include iron overload states (such as in patients who receive chronic blood transfusions or those with hemochromatosis) and the use of desferrioxamine, a bacterial siderophore. Infections caused by Y enterocolitica are more common in children than adults.

Important Anaerobes

Anaerobic bacteria are the predominant component of the normal microbial flora of the human body. The following sites harbor the vast majority of them:

Important Anaerobes: Clinical Syndromes

Box 1 summarizes different clinical syndromes associated with anaerobic bacteria. The sections that follow describe the various syndromes, including clinical findings. For some syndromes, specific diagnosis and treatment information is included as well.

Legionella

More than 25 species and 48 serogroups of Legionella have been identified. Legionella pneumophila (especially serogroup 1) causes ~ 70-80% of cases of legionellosis, but L micdadei, L bozemanii, L dumoffi, L feelei, L longbeacheii, and other species are also pathogenic. The true incidence of legionellosis, which includes Legionnaires’ disease and Pontiac fever, is difficult to establish.

Legionella: Clinical Syndromes

Legionella species are associated with outbreaks of either Pontiac fever, a self-limited influenzalike condition in otherwise healthy people, or Legionnaires’ disease, a severe pneumonic disease more common among elderly and immunocompromised individuals.

Vibrio & Campylobacter

Cholera is a disease of antiquity and probably represents some of the diarrheal illnesses described by Hippocrates and other early physicians. Robert Koch discovered V cholerae in 1884. Since the 17th century, at least eight epidemics of cholera have swept the globe. At least seven of the eight pandemics originated from the Ganges River delta, where cholera is endemic.