Question | Answer |
What are the medically important gram positive rods? | bacillus, corynebacterium, erysipelothrix, gardnerella bacillus |
What is bacitracin produced from? | B. subtilis |
What are the virulence factors in bacillus? | endospores, enterotoxins |
What are the important species? | B. anthracis, B. cereus, B. subtilis, B. sterothermophilus |
What is the etiological agent of anthrax? | B. anthracis |
What are the three clinical presentations of anthrax? | cutaneous, gastroenteritis, inhalation |
What are the two clinical presentations of B. cereus? | gastroenteritis (mediated by enterotoxins) and ocular (trauma --> rapid, progressive destructions) |
What is the classic radiographical presentation of anthrax? | widened mediastinum |
Corynebacterium | genus of Gram positive rods, often irregularly shaped |
How well do corynebacterium grow on lab media? | readily |
What is the etiologic agent of diphtheria? | C. diphtheriae |
Where is C. diphtheriae found in normal flora? | skin, GI, GU and respiratory tracts |
diptheroids | corynebacterium |
What two genera are often grouped together in microbiology because both are aerobic rods with similar microscopic morphology? | erysipelothrix, listeria |
erysipelothrix | small, thin rods that form long filaments, grows slowly in vitro, little known about its virulence factors |
Listeria | small, paired coccobacilli |
Out of the 3 species of erysipelothrix found in humans, which is associated with disease? | E. rhusiopathiae |
Where is erysipelothrix colonized? | many animals, especially turkey, swine, fish |
How do erysipelothrix infections move to humans? | zoonotic, cutaneous - butchers, farmers, vets |
What does systemic form of erysipelothrix cause? | rare - usually endocarditis |
Where is listeria widely found? | in animals |
What other places can listeria be found? | soil, water, vegetation, variety of mammals, fish, fowl |
how is human disease from listeria transmitted? | by contaminated food, vertical, zoonotic |
Who is at risk for listeria infection? | neonates, elderly, pregnant women, cancer/transplant patients |
What are the virulence factors of listeria? | hemolysin, listeriolysinO, ability to survive in cold temperatures |
What are the medically important anaerobic gram positive rods? | actinomyces, clostridium, lactobacillus, mobiluncus, propionbacterium |
Where do anaerobic medically important gram positive rods typically colonize? | skin and mucosal surfaces |
actinomyces | filamentous morphology; resembles hypae |
What is the most common actinomyces infection in humans? | A. israeli |
Where do actinomyces typically colonize in humans? | upper respiratory, GI and female genital tracts |
What does actinomyces cause? | low virulence - cause infection when mucosal barriers are disrupted, often chronic |
Clostridium | spore formers, spores more prominent in some species than others |
Where is clostridium ubiquitious? | soil, water, human GI tract |
What are the four medically important clostridium infections? | C. perfringens, C. botulinum, C. tetani, C. difficile |