Block 1

Front 1

Biochemical Analysis (Biotyping)

Back 1

Distinguishes bacteria based on metabolism, formation of distinct biochemical end products, presence of enzymes/toxins, or requirement of specific nutrients

--> Info from selective/differential/enrichment media

Front 2

Selective Media

Back 2

Components in the media inhibit the growth of some types of organisms allowing others to grow

Example: growth of pathogens vs. non-pathogens

Front 3

Differential Media

Back 3

More than one type of organism will grow, but media allows for differentiation based on biochemical rxns

Front 4

Enrichment Media

Back 4

includes growth factors that enhance/or are required for the recovery of "fastidious" microbes

Ex: legionella needs cysteine to grow on plate

Front 5

BAP

Back 5

Contains 5% sheep blood and is a differential media

Front 6

Three types of BAP hemolysis?

Back 6

gamma = do not hydrolyze RBCs

alpha= partially hydrolyze

beta= completely hydrolyze

Front 7

CHOC (chocolate agar)

Back 7

Enriched medium with 5% sheep blood with lysed RBCs -> for organisms which need RBC nutrients but cannot lyse RBCs on their own

Front 8

Thayer Martin/ NYC agar

Back 8

Modified CHOC agar containing antibiotics which prevent the growth of normal genital flora and selectively allow Neisseria species to grow

(so it is SELECTIVE)

Front 9

MSA (Mannitol Salt)

Back 9

Selective and Differential media which contains 7.5-10% salt which inhibits all organisms growth EXCEPT for Staph species.

Mannitol salt is nutrient for Staph which is fermented resulting in color change of medium from red to yellow (changes to acidic pH)

Front 10

MacConkey

Back 10

Selective and Differential agar which contains bile salts and dyes which inhibit gram + microbes but allows most gram neg to grow. Also contains lactose which may be fermented by some of the gram (-) resulting in pink to purple

Front 11

BAP agar

Back 11

Front 12

CHOC agar

Back 12

Front 13

MSA agar

Back 13

Front 14

MacConkey Agar

Back 14

Front 15

Hektoen Agar

Back 15

Front 16

CHROMagar

Back 16

Front 17

ENT Agar

Back 17

Front 18

MYC agar

Back 18

Front 19

Hektoen Agar

Back 19

Selective and Differential media that contains lactose, thiosulfate, iron, green dye, and gram + inhibitory salts. Organism that utilize thiosulfate have sulfide as by-product -> leads to production of H2S -> reacts w/ iron to form black precipitate

*Used to differentiate salmonella from shigella

*Shigella= green colonies/ Salmonella = H2S producing so green w/ black centers/ Lactose fermenters= salmon colored

Front 20

ENT

Back 20

Selective/Differential media that contains bile (inhibits gram +) and sodium azide (inhibits gram-) w/ esculin+peptone for nutrients and ferric citrate as color indicator.

Few organisms can hydrolyze esculin in presence of bile-> will produce esculetin-> reacts with ferric to form dark black precipitate

Front 21

CHROM agar

Back 21

Selective & Differential media which utilizes chromogen that releases differently colored compounds upon degradation by specific microbial enzymes= direct differentiation of certain species

Front 22

MYC & SAB

Back 22

Selective media for FUNGI

Contains antibacterial agents & usually an acidic pH

Front 23

Catalase Test

Back 23

Organisms producing catalase able to detoxify some chemicals that are part of host intracellular killing pathway.

Drop of h202 (Hperoxide) on a colony= bubbles or no bubbles

Staph is catalase + and Strep is catalase -

Front 24

Oxidase

Back 24

Some bacteria use different chemicals (besides cytoC oxidase) as the final electron acceptor and are oxidase neg (ex: enterobacteria); fecal bacteria

**Drop N,N,N',N'-tetramethyl-p-phenylenediaminedihydrochlorideon a colony +/- dark purple color.

Examples of gram neg BUT oxidase + are pasteurella multocida, haemophilus influenza, vibrio spp, campylobacter, and helicobacter spp

Front 25

Coagulase Test

Back 25

coagulase->reacts w/ prothrombin-> fibrinogen to fibrin-> leads to coagulation and clotting. Preformed Abs against coagulase are mixed w/ microbes which produce protein and agglutination results

*IDs Staph aureus and Yersinia pestis

Front 26

Nitrite using Nitrate broth (dipstick)

Back 26

Differential medium used to determine if an organism is capable of reducing nitrate to nitrite

**Important for Enterobacteriaciae (UTIs)

**If nitrate broth turns red= positive result

Front 27

Urease Test

Back 27

Broth that contains pH indicator which is orange at neutral pH. If bacteria produces urease (converts urea to ammonia)= increase in pH (more basic) causes solution to turn deep pink

Front 28

Indole Test

Back 28

test to determine ability of bacteria to split tryptophan into indole, pyruvate, and ammonium using Kovac's reagent (glycolytic pathway)

Gram- rod = indole +

***Bright RED colored product

Lactose fermentation= E. coli

Front 29

Sensitivity Test / Susceptibility Test

Back 29

Either resistance is shown (growth on media) or inhibition (micro cannot grow in presence of substance)

Front 30

Sugar Fermentation

Back 30

Test using tubes where sugar is added to a nutrient rod and the fluid inside test has a pH indicator

RED= no fermenting; Yellow= fermentation

Can also be yellow w/ gaseous product

Front 31

Serotyping

Back 31

Using preformed Abs to identify Ags on surfaces of expected pathogens

**Salmonella serotyping by agglutination

**Ouchterlony Test for Diptheria toxin= preciptation where Ab meets the toxin

Front 32

Serology

Back 32

Analysis of Abs in patients SERUM

-> can do Paired Sera= take serum at two different times and see if titer has increased (indicates active infection). Useful for common population exposures; and organisms that cannot be tittered until later in the disease

->OR send in fluid to see if multinucleated bodies present

Front 33

Molecular Diagnosis

Back 33

Sensitive/Specific diagnosis; safest for highly virulent infectious organisms, not useful for diagnosing "life-long" infections

Includes NAATs and In Situ Hybridization: Gonorrhea, Chlamydia, HSV, Trichomonas, Candida, and Gardnerella

Front 34

Other types of testing

Back 34

physical examination (auscultation, palpation, percussion, HEENT, etc)

Chem panels

CBC= complete blood count [% lymphocytes, neutrophils (virus), and eosinophils (parasites)]

skin tests

x-ray, ecg, etc.

Front 35

What is the purpose of antimicrobial agents?

Back 35

To compliment or assist the host's immune defense; to reduce # of bugs so that healthy individual's immune system can eliminate the rest

Front 36

What is Empiric Therapy?

Back 36

Starting TRX with antimicrobial before confirmation of the actual causative agent; based on best-guess & experience of physician

** life-threatening, helps w/ patient satisfaction

Front 37

What is selective toxicity?

Back 37

Ability to kill pathogen instead of or before killing the host's cells

Broad= kills many different types of microbes

Narrow= kills only a few microbes

Ex: Acyclovir as prodrug only becomes activated when it makes it to a cell that is infected with HSV

Penicillin only targets peptidoglycan on gram+

Front 38

What are adverse host reactions?

Back 38

Reactions while taking antimicrobials, may be unrelated to the mechanism of axn of the drug

Ex: Penicillin can act as a hapten and cause allergic rxns

Front 39

What are the two types of drug actions?

Back 39

1. Static = prevents growth of microbe (replication); assists immune system by limiting # of microbes being produced (Ex: if gram- want to limit release of LPS toxins to prevent endotoxic shock)

2. Cidal= destroys the bacteria

Front 40

What is the drug susceptibility, or MIC?

Back 40

MIC= Minimum Inhibitory Concentration

*Minimum dose to achieve static effect; MIC is NOT the drug dosage (must be higher for metabolism compensation)

Front 41

Back 41

Antibiotic Antagonism= adding antimicrobial limits the toxic effect of another

Front 42

Back 42

Antibiotic Synergism= adding antimicrobial to another leads to synergistic effect and more thorough clearance of the bacteria

EXAMPLE: Enterococcus faculae can have its protein synthesis inhibited by aminoglycoside; but can only reach ribosomes after penicillin is introduced to destroy cell wall to allow entry

Front 43

What are antibiograms?

Back 43

Tests analyzing patterns of susceptibility and resistance to different antibiotics in order to choose a best treatment. [normally performed by lab after causative agent identified]

--> Ex: Neisseria Gonorrhea can be antibiotic resistant; may need to measure higher doses to see if effective

Front 44

Bauer Test (Disc Diffusion)

Back 44

Antibiogram measuring inhibition vs growth (resistance)

aka Disc Diffusion

Front 45

E Test

Back 45

Antibiogram used to see how high a dosage of antibiotic can be used without doing damage to the host. Tests different concentrations of drugs; also helps w/ patient compliance b/c higher dose means fewer days

Front 46

D Test

Back 46

Antibiogram which tests to see if bugs are no longer susceptible to a certain antibiotic when taken in concordance with another.

Front 47

What are the four ways microorganisms become resistant to antibiotics/antimicrobials?

Back 47

Target organelle/structure/enzyme alteration: enetic mutation altering binding site of the antibiotic -> drugs= macrolides, Vancomycin

Active Efflux: pumps out antibiotic using naturally occuring/mutated permeases-> drugs affected are Macrolides, Clindamycin, Tetracyclines, & Fluouroquinolones

Existing Microbial Structures: Such as LPS in Gram -

Inactivation or degradation of antimicrobial agent (enzymes)-> Drugs affected are beta-lactams, aminoglycosides

Front 48

Antibacterial Agents that inhibit cell wall synthesis

Back 48

*Beta-lactams bind PBP (penicillin binding proteins) (Example: Augmentin is combination drug using beta-lactam and clavulanic acid which is an inhibitor of beta-lactamase); include Penicillin and its derivatives

*Glycopeptides (Ex: Vancomycin)

Front 49

Antimicrobial agents that inhibit the protein synthesis pathway

Back 49

M.A.L.T.

Macrolides

Aminoglycosides

Lincosamides

Tetracyclines

*All high selective toxicity b/c sensitive for ribosomes of prokaryotes

Front 50

Antimicrobial agents that inhibit nucleic acid synthesis

Back 50

"Nucleic Acid Synthesis is So Much Fun"
Fluoroquinolones

Sulfonamides

Metronidiazole

*If micro can pick up thymidine exogenously they are intrinsically resistant to sulfonamide

Front 51

Antimicrobial agents that cause injury to the plasma membrane (and/or LPS of gram-)

Back 51

Polymyxin family of polypeptide antibiotics

"LPS, Polymyxin"

Front 52

Antivirals that disrupt:

1. Attachment

2. Uncoating

3. Replication

Back 52

1. Attachment: Enfuviritide

2. Uncoating: Amantadine, Arildone, Rimantadine, Tromantadine (also FUSION)

3. Replication: Phosphonoformate

Front 53

Antivirals that disrupt:

6. Nucleotide Synthesis

7. Thymidine Kinase

8. Neuraminidase (release)

Back 53

6. Nucleotide synthesis: Ribavirin

7. Thymidine Kinase: Acyclovir, Penciclovir

8. Neuraminidase (release): zanamivir,

oseltamivir

Front 54

Antifungal Drugs

1. Alters Plasma Membrane

2. Inhibits cell wall synthesis (glucan/mannan)

3. Disrupts microtubule structure

4. Inhibits nucleic acid synthesis

5. Blocks folic acid synthesis

Back 54

1. Fluconazole, Amphotericin B (polyenes)

2. Caspofungin, Nikkomycin

3. Griseofulvin

4. Flucytosine

5. Sulfonamides

Front 55

Anti-parasitic Drugs

1. DNA replication

2. Folic Acid biosynthesis

3. Transport disruption

4. Inhibition of Neuromuscular Action

Back 55

1. Mefloquine, Metronidazole

2. Sulfonamides

3. Mebendazole

4. Ivermectin