Klebsiella
Classification General Characteristics General characteristics Gram-negative bacilli Facultative anaerobes Non-motile Encapsulated (polysaccharide capsule) Single, in pairs, or short chains Form large, mucoid colonies Major pathogenic species: Klebsiella pneumoniae Biochemistry Lactose fermenters: Ferment lactose to lactic acid Pink colonies on MacConkey agar Urease positive: hydrolysis of urea into ammonia and carbon dioxide Oxidase negative Can use […]
Chlamydia
General Characteristics General characteristics Obligate intracellular bacteria: Cannot produce their own adenosine triphosphate (ATP) Capable of synthesizing their own macromolecules Staining: Visualized using Giemsa stain: nucleic acid stain Classified as gram-negative bacteria, but exhibit poor Gram staining Cell wall shows some characteristics of gram-negative bacteria, but lacks peptidoglycans. Lack of peptidoglycans makes them insensitive to […]
Rickettsia
General Characteristics General characteristics Transmission and geography Table: Summary of major clinically relevant species R. rickettsii R. prowazekii R. typhi R. akari Vector Hard ticks (Ixodidae family): Dermacentor (dog tick), Amblyoma (wood tick) Human lice (Pediculus humanus corporis): Defecate on skin Host scratches area. Bacteria enter the skin. Eastern flying squirrels along with their lice […]
Proteus
Classification General Characteristics Proteus spp. Clinically relevant species Epidemiology Pathogenesis Reservoir and transmission Virulence factors Disease process Clinical Presentation Diagnosis and Management Diagnosis Treatment Comparison with UTI-associated bacteria Escherichia coli (E. coli) and Proteus spp. are common etiologies of urinary tract infection. Table: Different factors of Proteus spp. versus E. coli Proteus spp. E. coli […]
Bacillus
Classification General Characteristics Basic features of Bacillus spp. Pathogenic species B. anthracis Epidemiology Transmission Pathogenesis Clinical presentation In the United States, 3 clinical manifestations occur. Identification Management Prevention B. cereus Epidemiology Transmission Pathogenesis Clinical presentation Identification References
Yersinia pestis/Plague
General Characteristics Basic features of Yersinia pestis Structure: bacilli/rods Gram stain: gram negative Other stain(s): Stains such as Wright’s, Giemsa’s, and Wayson’s Bipolar staining (retain staining at the ends of the cells) or “safety pin” appearance Spore formation: non-spore forming Invasion and replication in relation to the host cell(s): facultative intracellular Oxygen requirement: facultative anaerobes […]
Yersinia spp./Yersiniosis
Classification General Characteristics Basic features of Yersinia spp. Structure: bacilli/rods Gram stain: gram negative Other stain(s): Stains such as Wright’s, Giemsa’s, and Wayson’s Bipolar staining (retain staining at the ends of the cells) or “safety pin” appearance Spore formation: non-spore forming Invasion and replication in relation to the host cell(s): facultative intracellular Oxygen requirement: aerobic, […]
Clostridia
Classification General Characteristics Basic features of Clostridium species Pathogenic species Table: Compare and contrast Clostridia species C. botulinum Clostridioides difficile C. perfringens C. tetani Habitat Soil Marine sediments Intestinal flora Soil Intestinal flora Soil Intestinal flora Virulence Botulinum toxin Enterotoxin A Toxin B Alpha toxin Enterotoxin Tetanus toxin (tetanospasmin) Transmission Ingestion of: Spores Preformed toxin […]
Corynebacterium
Classification General Characteristics Basic features General characteristics of Corynebacterium species include: Growth and biochemical properties Clinically relevant species Corynebacterium diphtheriae Epidemiology Transmission Virulence factors Clinical presentation Diphtheria (respiratory): Complications/systemic toxemia: Cutaneous (wound) diphtheria: Identification Prevention Management Mnemonic “ABCDEFGs of Corynebacterium diphtheriae”: References
Bordetella
Classification General Characteristics Basic features of Bordetella Biochemistry and growth Pathogenic species Bordetella Pertussis Epidemiology Transmission Pathophysiology Pathogenesis: Virulence factors: Clinical presentation Identification Specimen collection: Tests: Prevention References