B3-003 Prework 1 Intro to Lab Diagnosis Culture

Question 1

What are Koch’s postulates

Answer 1

1. Microorganism present in every case of the infectious disease
2. Microorganism can be isolated in pure culture
3. Inoculation of pure culture into animals produces similar disease
4. Same species of micro organism recovered from diseased animal

Question 2

What are the arrangements of spherical bacterial cells

Answer 2

Diplococcus
Tetrad
Streptococcus
Staphylococcus

Question 3

What feature of gram negative bacterial cell wall is an endotoxin

Answer 3

Lipopolysaccharide –> shock

Question 4

In a gram stain what happens to gram positive bacteria

Answer 4

they stain violet

Question 5

In a gram stain what happens to gram negative

Answer 5

it stains pink

Question 6

What is an obligate aerobe

Answer 6

requires oxygen for growth

Question 7

What is facultative anaerobe

Answer 7

will grow in aerobic and anaerobic conditions

Question 8

What is microaerophilic

Answer 8

grows best with low concentrations of oxygen

Question 9

What is obligate anaerobe

Answer 9

Oxygen is toxic

Question 10

What are fermenters

Answer 10

Fermentation of glucose and lactose used to characterize organisms

Question 11

How do you measure fermentation

Answer 11

Byproducts - Lactic acid, butric acid, mixed acids

Question 12

When your patient has an infection what are the diagnostic tests you can choose from

Answer 12

microscopy, culture, serology, molecular biology

Question 13

What is molecular biology

Answer 13

nucleic acid detection

Question 14

Sputum specimen is from

Answer 14

lower respiratory tract

Question 15

What are the normal bacterial flora of upper respiratory tract

Answer 15

Staph sp.
Strep sp.
 - Strep pneumoniae
 - Viridans strep
Haemophilus sp
Anaerobes

Question 16

What is the normal bacterial flora of the skin

Answer 16

Staph sp
Coryneform bacteria or diptheroids
Propionibacterium sp

Question 17

What is the normal bacterial flora of the GI tract

Answer 17

anaerobes
enterococcus sp
enterobacteriaceae
Enterobacteriaceae
- Escherichia coli
- klebsiella sp
Strep anginosus
Lactobacillus sp
candida sp

Question 18

What are the normal flora of the Genital tract

Answer 18

Lactobacillus sp

Strep agalactiae

Question 19

what types of specimens do you use direct gram stain

Answer 19

sputum, positive blood culture, abscess fluid, CSF, vaginal discharge

Question 20

What is an enriched culture

Answer 20

contains nutrients to support growth of a wide variety of organisms

Question 21

What is a selective culture

Answer 21

inhibits growth of certain groups of organisms

Question 22

What is a differential

Answer 22

distinguish organisms based on growth characteristics

Question 23

What are key concepts of blood cultures

Answer 23

Draw before antibiotics

Fill bottles

Question 24

What is a viral culture grown with

Answer 24

mammalian cells

Question 25

What type of hemolysis is green and shows incomplete lysis around a colony

Answer 25

alpha

Question 26

What type of hemolysis has a clear zone around the colony

Answer 26

beta

Question 27

What type of hemolysis has no hemolysis

Answer 27

gamma

Question 28

What organism produces a yellow pigment on a blood agar

Answer 28

Staphylococcus aureus

Question 29

What organism grows red/pink colonies

Answer 29

Serratia marcascens

Question 30

What organism grows green/blue colonies

Answer 30

Pseudomonas aeruginosa

Question 31

What are the colony characteristics of Klebsiella pneumoniae

Answer 31

mucoid

Question 32

What are the colony characteristics of candida albicans

Answer 32

Projections

Question 33

What are the colony characteristics of proteus vulgaris

Answer 33

Swarming

Question 34

What are 3 enzymatic tests

Answer 34

Catalase Coagulase Oxidase

Question 35

What organisms exhibit alpha hemolysis

Answer 35

S. Pneumoniae S. Mutans Viridans group

Question 36

What organisms exhibit beta hemolysis

Answer 36

S. Pyogenes (GAS) | S. agalactiae (GBS)

Question 37

what is an organism that exhibits gamma hemolysis

Answer 37

enterococcus

Question 38

what types of antimicrobial susceptibility testing are there

Answer 38

Genotypic - PCR based detection of the genes associated with resistance to a drug Phenotypic - tests ability of organism to grow in presence of drug

Question 39

What are advantages of PCR based detection of genes associated with resistance to drug

Answer 39

Fast Very sensitive Very specific

Question 40

What are limitations of PCR

Answer 40

Expensive | Single target

Question 41

What are examples of phenotypic susceptibility testing

Answer 41

``` MIC Agar dilution Broth microdilution Disk diffusion Strip (Etest) ```