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Flashcards in Respiratory Bench Deck (25)
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Classify the types of respiratory specimens that can be cultured as "non-sterile" relating to the normal flora content of the original site

Expectorated or induced sputum
Endotracheal aspirates
Bronchioalveolar lavage
Bronchial washings
Bronch brushes


Classify the types of respiratory specimens that can be cultured as "sterile" relating to the normal flora content of the original site

Transtracheal aspirates
Lung aspirates
Pediatric BAL


Normal Flora of the respiratory tract

1. Strep viridian's group
2. Corynebacterium
3. Neisseria species
4. Coag Negative Staph
5. Rothia
6. Group F streptococci
7. Haemophilus spp other than influenzae
8. Enterococcus species
9. Candida
10. Eikenella corrodens
11. Capnocytophaga species
12. Moraxella species


5 common "potential pathogens" of the lower respiratory tract

1. Streptococcus pneumoniae
2. Strep pyogenes
3. Haemophilus influenae
4. Staphylococcus aureus
5. Cryptococcus neoformans
6. Moraxella catarrhalis
7. Neisseria meningitidis
8. Gram Negative Rods


OSOM Ultra Strep A Test
- time?
- principle?

- occurs in 7 minutes
- color immunochromatographic assay using dual label technology
- extraction, form complex with anti-group A strep antibody conjugated to color particles; complex will then bind to capture antibody and visible blue test line will appear.


OSOM Ultra Strep A Test
- collect from where?
- problems with it?

sterile swab from tonsils and or back of throat
- Rapid strep screen: rapid, but not sensitive but very specific


"Strep Throat" screen
- procedure

Swab of the tonsillar areas and posterior pharynx; BAP incubated in anaerobic glove box for 48 hours; screen BAP for beta strep group A only; strep latex test is performed on beta strep for identification.


What specimen types can receive a report of "normal flora"? and what specimen types require listing of all organisms isolated?

"normal flora" - non-sterile
All organisms - sterile


When are expectorated or induced sputums, and endotracheal or tracheostomy aspirates considered unsatisfactory for culture workup?

if there are > 10 squamous epithelial cells per low power field


How do you quantitate growth of organisms on respiratory culture media?

dependent on quadrant where organisms are growing (1+/few, first quad; 2+/moderate, second quad, 3+/many, third quad; 4+/many , fourth quad)


Pathogens commonly isolated from Cystic Fibrosis patients

Staphaureus or Haemophilus
Pseodomonas aeruginosa
Burkholderia cepacia
Stenotrophomonas maltophilia


Susceptibilities for Pseudomonas aeruginosa

colistin e-test


Susceptibilities for Stenotrophomonas maltophilia

Moxifloxacin and minocycline e-test


Cystic Fibrosis:
- choice of selective media
- length of incubation
- purpose of selective media

- PC and Mannitol Salt agar (MSA) plates
- on day two incubated in ambient air incubator
- PC agar for Burkholderia cepacia
- MSA agar


Appropriate Media for:
- Throat strep screens



Appropriate Media for:
- Throat/Pharynx

BAP with stab
Special Request: choc, Mod Thayer Martin, Loeffler/Tellurite


Appropriate Media for:
- Nose/nasopharynx

BAP, Chrom Agar
Special Request: Mod Thayer Martin, Bordet-Gengou or Regan Lowe


Appropriate Media for:
- Routine Sputum (sputum, endotracheal suction, tracheal aspirate, Luken's trap)

BAP with stab, Choc, Mac, and CNA


Appropriate Media for:
- Bronchial wash/Unprotected brushing

BAP with stab, Choc, Mac, and CNA


Appropriate Media for:
- Bronchoaviolar lavage (BAL)
- Protected brush

Quantitative cultures using calibrated loops
BAP with stab, Choc, Mac, CNA, Thio Broth


Appropriate Media for:
-TransTrachial aspirate, "steriles", Pediatric BAL

BAP with stab, Choc, Mac, and CNA
Thio Broth, anBAP, anPEA, anKV


Appropriate Media for:
- Legionella Culture

BCYE with and without antibiotics after processing with 1:10 KCL:HCL
Routine Culture: BAP with stab, Choc, Mac, and CNA


What media is kept at 35C in CO2 for 48 hours? Give purpose of each

1. MAC - GNR, lactose reaction
2. BAP - general purpose media, hemolysis
3. Choc - enriched for Hemophilus and Neisseria sp.
4. CNA - Gram positive organisms


What media is kept at 35C in non CO2 incubator for 48 hours? Give purpose of each

1. Chrom ID agar - for MRSA
2. Thio - general purpose media, enhances the growth of anaerobes


What media is kept at 35C in anaerobic incubator for 48 hours

1. anBAP - general purpose media, isolation of anaerobes, hemolysis
2. anKV - isolate anaerobic GNR
3. anPEA - isolate anaerobic GPC