Gram-negative Bacteria & Diseases Flashcards
Describe cell morphology of Neisseria species
- gram-negative diplococci
- often found in neutrophils in cerebrospinal fluid and urethral discharge
- Pili responsible for urethral colonization
Nisseria species and diseases
N. gonorrhoeae: STI
N. meningitides: respiratory-transmitted infection of CNS
Describe bacteriological properties of Enterobacteriaceae in regard to their identification
- gram-negative, non-spore forming bacilli
- use NO3 for anaerobic respiration
- negative for cytochrome C oxidation (defining test)
- ferment glucose
- peritrichous if motile
- O and H antigens identifies specific strains
- K capsule antigen diagnostic if present
Moraxella catarrhalis
- gram-negative, diplococcus
- aerobic
- unencapsulated (low virulence, easily phagocytized)
- normally in nasopharynx
- pneumonia in elderly
Describe the bacteriological properties and diseases caused by Y. pestis, its reservoir, and transmission
(black plague)
- Enterobacteriaceae
- bipolar staining coccobacillus
- resevoir: rats, prairie dogs, squirrels, etc
- transmitted by rat flea
- fatal if not treated within a day
Describe the bacteriological properties and diseases caused by F. tulerensis, its reservoir, and transmission
-gram-negative coccobacillus
-aerobic
-symptoms:
- ulceroglandular: fever, ulcer at bite site, swollen
lymph nodes
- glandular: lymph nodes but no ulcer
- oculoglandular: enters by eye – eye inflammation,
lymph nodes
- oropharyngeal: by ingestion – sore throat, ulcers
- pneumonic: by inhalation – pneumonia
- typhoidal: fever without local findings
-resevoir: langomorphs (rabbits, hares, etc) and aquatic rodents
-transmitted by various ticks and deer flies (anthropods)
-low infectious dose, easy to aerolize, high virulence (potential weapon of mass destruction)
Describe the bacteriological properties and diseases caused by C. burnetti, its reservoir, and transmission
- gram-negative
- can multiply in cell
- motly asymptomatic, fever, headache, cough, pneumonia
- incubation period of 20 days
- resevoir: cattle, sheep, goats, rich in placenta
- transmitted by inhalation of aerosol (no vector)
- if mom gets – transmitted to placenta –fetus dies
Describe the bacteriological properties and diseases caused by B. henselae, its reservoir, and transmission
(Cat scratch disease)
- gram-negative bacillus
- long incubation period (1-3 weeks)
- low fever, vesicle/red lesions at primary lesion, enlarged nodes
- resevoir: domestic cats
- transmitted via scratch (possibly anthropods)
Describe the bacteriological properties and diseases caused by Pasteurella multocida, its reservoir, and transmission
- gram-negative rod
- intense wound infections appearing in 24 hours
- resevoir: dogs and cats
- transmitted via bite
How does lactose-fermentation determine if an Enterobacteriaceae is pathogenic or not?
ferments lactose – good
doesn’t ferment lactose – pathogenic
Apply knowledge of the zoonotic bacterial infections to clinical scenarios
increasing exposure to animals allows viruses to jump to humans