Microbiology Review (Ch 4) Flashcards Preview

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Flashcards in Microbiology Review (Ch 4) Deck (15)

Gram Positive Cocci (GPC): 

Major subgroups? (3)

Major pathogens?

Less common pathogens? (in italics)

Gram Positive Cocci (GPC):

Staphylococci, Streptococci, Enterococci

Staph: Staph Aureus, S. epidermidis

Strep: Strep pneumoniae ("pneumococcus"), Viridans strep, Group A Strep ("pyogenes"), Group B Strep (S agalactiae), Group C, Group G

Enterococci: E. faecalis, E. faecium


Gram-Negative Rods (GNR):

Major subgroups?

Major pathogens?

Less common pathogens (in italics)?

Gram-Negative Rods (GNR):

(Aerobes) Enterobacteriacae, Vibrios

Enterobacteriaceae: E Coli, Klebsiella, Enterobacter, Proteus, Salmonella, Shigella, Yersinia, Serratia, Citrobacter, Morganella

Vibrios: Vibrio cholerae, Vibrio parahaemolyticus

Also: Pseudomonas, H influenza, Legionella, Moraxella cararrhalis, Acinetobacter, Campylobacter, Helicobacter, Bartonella, Pasturella, Bordetella, HACEK group


Gram-Negative Cocci (GNC):

Major subgroups? (1)

Major Pathogens? (2)

Gram-Negative Cocci (GNC):

Neisseria: Neisseria meningitidis ("meningococcus"), Neisseria gonorrhoeae ("gonococcus")



Major Subgroups? (3)

Major Pathogens? (2)

Less common pathogens?


Oral anaerobes, Bowel anaerobes, Clostridium spp

Oral anerobes: Anaerobic strep, Bacteroides, Fusobacterium, Prevotella, Actinomyces

Bowel anaerobes: Bacteriodes fragilis, Anaerobic strep

Clostridium spp: Clostridium difficile, C. perfringens, C. tetani, C. botulinum


Gram Positive Rods (GPR)

Major subgroups? (4)

Major pathogens? (0)

Less common pathogens? (5)

Gram Positive Rods (GPR):

Listeria, Corynebacterium, Bacillus, Nocardia

Listeria: Listeria monocytogenes

Corynebacterium: Non-diphtheria Corynebacterium, C diphtheriae

Bacillus: B anthracis (Anthrax), B cereus


Lack a typical cell wall so don't gram stain!

Major subgroups? (5)

Major Pathogens? (4)

Less common pathogens? 6)

Lack a typical cell wall so don't gram stain!

Mycobacteria, Spirochetes, Mycoplasma, Chlamydia, Rickettsia

Mycobacteria: M tuberculosis, Non-tuberculous mycobacteria

Spirochetes: Treponema pallidum (syphilis), Borrelia burgdorferi (Lyme)

Mycoplasma: M. pneumoniae

Chlamydia: C. trachomatis, C. pneumonia

Rickettsia: Rickettsia rickettsii (RMSF), Ehrlichia, Anaplasma


Pneumococcus (Strep pneumonia)

-gram stain and shape?

-most common cause of what?

-common cause of what? (2)

-part of normal flora where?


-what structure is impt for virulence?

Pneumococcus (Strep pneumonia)

-Gram positive cocci, lancet shaped

-Most common cause of bacterial pneumonia

-Common cause of meningitis and otitis

-part of normal throat flora (mixed w other bugs)

-Tx = penicillin -- but emerging resistance means we have to use Vanco, others

-Capsule is impt for virulence


Group A streptococcus (Strep pyogenes)

-why called "beta-hemolytic" strep?

-gram stain and shape?

-Causes what (2)

-Late sequelae are what? (2)

-Sensitive to what drug?

-Presence in what flora suggests disease?

-Various types of Group A strep are based on what?

Group A streptococcus (Strep pyogenes)

-"beta hemolytic: causes complete hemolysis on blood agar plates

-Gram positive cocci (GPC) in chains

-Causes pharyngitis, wound infections

-late sequelae: rheumatic fever, acute glomerulnephritis

-sensitive to PCN G (except enterococci)

-NOT usually part of normal throat flora: presence there -> disease

-Types of Group A strep based on differences in the "M" protein, within the cell wall


Group B Strep (Strep agalactiae)

-sensitive to what?

-normal flora of what?

-impt cause of what conditions? (2)

-are they beta hemolytic?

Group B Strep (Strep agalactiae)

-mostly sensitive to PCN G

-inhibit female genital tract

-cause neonatal septicemia and meningitis

-many strains (not all) are beta hemolytic


Viridans streptococci

-gram stain and shape?

-predominant organism where?

-most common cause of what?

-usual treatment?

-a few species?

Viridans streptococci

-Gram Positive Cocci in chains or pairs

-Predominant org in normal oral cavity

-most common cause of subacute bacterial endocarditis on damaged valves

-usual treatment for SBE: penicillin may be sufficient

-Species: S mutans, S sanguis, S salivarius, S mitis


Enterococcus faecalis (Strep faecalis)

-Gram stain and shape?

-normal where?

-causes what? (2)

-resistant to what?

-sensitive to what?

-what are VRE?

Enterococcus faecalis (Strep faecalis)

-Gram Positive coccus, pairs and chains

-normal fecal flora

-causes UTIs (10%)

-#2 cause of endocarditis (less common than Viridans strep)

-"resistant" streptococcus because resistant to PCN

-Ampicillin is used (with exceptions)

-VRE = Vancomycin Resistant Enterococcus


What are the 3 GPCs?

Staph, Strep, Enterococci


What are the 2 GNCs?

Neisseria meningitidis, Neisseria gonorrhoeae

(meningogoccus, gonococcus)


5 that don't gram stain because they lack a cell wall?