pneumococcus- Daniels Flashcards
streptococcus pneumoniae characteristics
- gram positive cocci
- diplococci
- aerotolerant anaerobe
- non spore forming
- encapsulated
s. pneumoniae is the main cause of _____
community-acquired pneumonia worldwide
s. pneumoniae exhibits ___ hemolysis on blood agar
alpha
____ of young children is major reservoir for s. pneumonia
nasopharyngeal mucosa
transmission of s. pneu is by ____/____
respiratory secretions; hands
risk factors for establishment of infection
- viral infection (esp influenza)
- fluid in lungs for any reason
- season (winter/spring)
- smoking
- loss of consciousness (aspiration)
- high risk comorbities, age, demographics
s. pneumoniae can cause ____ in children and potential ____ to pneumonia in adults
otitis media (middle ear infection); sequelae
pneumonia in adults can cause ____ and _____
pleural effusion (fluid in chest, outside lungs); bacteremia –> meningitis
pneumococcus diagnosis
- presumptive from gram-stained sputum
- culture
pneumococcus therapy
- penicillins and other beta lactams (resistance is a concern)
- macrolides like erythromicin and azithromycin)
- fluoroquinolones (levofloxacin)
vaccine products are compromised of ____ (capsular) from multiple strains of s. pneumoniae
polysaccharide antigens
legionella pneumophila characteristics
- gram negative pleomorphic rod
- obligate aerobe
- fastidious; requires special conditions for lab
- cysteine requirement is identifying
L. pneumophila is transmitted through contaminated ____; is a parasite of _____
water; protozoa
l. pneumophila is ____ and is spread through _____ (NOT spread by cough)
thermotolerant (withstands 46C); environmental aerosols
virulent strains of l. pneumophila multiply within _____ (double membrane of rough ER)
autophagosomes
l. pneumophila have a ____ immune response; includes secretion of ____ and causes _____
cell-mediated; IFN-gamma; iron sequestration
virulence/proinflammatory mechanisms of L. pneumophila
- survival in macrophages
- LPS, flagellin
treatment for L. pneumphila
antimicrobials with good intracellular penetration; macrolides, fluoroquinolones, tetracyclines
penicillin not effective for L. pneumophila bc:
they do not reach therapeutic concentrations in macrophages
bordetella pertussis and parapertussis characteristics:
- gram negative rod
- obligate aerobe
- very contagious
- cause of whooping couch
pertussis colonizes the ____ and accesses the _____
nasopharynx; trachea/bronchi
ciliary adherence of pertussis via:
- filamentous hemagglutinin (Fha)
- pili (fimbriae)
- pertactin (a protein)
stages of pertussis seen clinically
- catarrhal stage
- paroxysmal stage
- covalescent stage
2 vaccines with acellular pertussis
DTaP- diptheria, tetanus, and acellular pertussis (routine 5 doses)
TDaP- lower doses of diptheria and pertussis components
canine infectious tracheobronchitis; part of kennel cough complex; rarely affects humans
bordetella bronchiseptica
mycobacterium species cause:
- tuberculosis (M. tuberculosis)
- leprosy (M. leprae)
- opportunistic diseases from tattoos, plastic surgery, environmental wounds, etc.
mycobacterium are ____ bacteria
acid fast
characteristics of mycobacterium
- gram positive obligate aerobes
- non-spore formers
- thick waxy cell wall
- mycolic acid binds carbol fuscin dye
diagnosis of tuberculosis
-intradermal skin test (use of killed antigen)
-acid fast sputum test
culture- very slow growing
PCR
leprosy is a ____ disease; organism prefers ____ temperature; spreads via _____ route
granulomatous; low (skin); respiratory
2 types of leprosy
tuberculoid and lepromateous
milder form of leprosy, may be self limiting; very few bacteria present in lesions
tuberculoid leprosy
in lepromatous leprosy which is severe and disfiguring, ____ is significantly decreased
cell mediated immunity
