Specimen Collection and Processing Flashcards
0
Q
How long should the specimen collection be postponed when the patient is under antibiotic therapy?
A
Wait 1 week after antibiotic therapy
1
Q
Method for obtaining anaerobic bacteria
A
Aspiration
2
Q
Level scheme of prioritization where the specimen is “critical” due to invasive collection or severity of disease
A
Level 1
3
Q
Level scheme of prioritization with organisms that easily multiply; processed immediately
A
Level 1
4
Q
7 specimens under Level 1 priority
A
- CSF
- brain
- blood
- heart valves
- pericardial fluid
- bronchoalveolar lavage
- amniotic fluid
5
Q
Level scheme of prioritization that may contain other organisms
A
Level 2
6
Q
Level scheme of prioritization that may be unprotected/unpreserved and may quickly degrade or have rapid overgrowth of contamination, changing the nature of the specimen
A
Level 2
7
Q
7 specimens under level 2 priority
A
- Sputum
- pus
- tissue
- drainage from wounds
- bone
- feces
- stool
8
Q
Level scheme of prioritization whose specimen requires quantitation (colony counting & quantitative tissue biopsy)
A
Level 3
9
Q
2 specimens under level 3 priority
A
- urine
- catheter tips
10
Q
Level scheme of prioritization whoses specimen is in a transport media
A
Level 4
11
Q
3 specimens under level 4 priority
A
- feces and urine in preservative
- swabs in holding medium
12
Q
7 body sites that are normally sterile
A
- CSF
- serous fluids
- lower respiratory tract
- bladder
- bone marrow
- blood
- tissue
13
Q
7 body sites that have normal commensal flora
A
- mouth
- nose
- upper respiratory tract
- gastrointestinal tract
- female genital tract
- urethra
- skin
14
Q
2 specimens obtained from the upper respiratory tract
A
- throat cultures
- nasopharyngeal cultures
15
Q
Bacteria obtained from throat cultures
A
Group A streptococci
16
Q
Type of sterile swab used for throat cultures
A
Calcium alginate
17
Q
5 infections detected in throat cultures
A
- streptococcal infections
- whooping cough
- epiglotitis
- oral thrush
- gonorrhoea
18
Q
Organism that causes oral thrush
A
Candida albicans
19
Q
2 bacteria obtained from nasopharyngeal cultures
A
- Neisseria meningitidis
- Staphylococcus aureus
20
Q
3 infections detected by nasopharyngeal cultures
A
- pertussis
- middle ear infections
- indentification of carrier state
21
Q
4 infections detected by lower respiratory tract specimens
A
- bronchitis
- pneumonia
- tuberculosis
- histoplasmosis
22
Q
3 specimens for lower respiratory tract
A
- sputum
- gastric contents
- transtracheal aspirations
23
Q
Specimen for lower respiratory tract for children and orderly who cannot cough out sputum
A
Gastric contents
24
Specimen for lower respiratory tract when the patient cannot produce gastric contents
Transtracheal aspiration
25
Time for best specimen of sputum
Early morning (deep cough & no saliva)
26
What is the time limit of refrigeration of histoplasmosis specimen when it is delayed?
Refrigerate not more than 1-3 hours
27
Specimen when the physician requires anaerobic culture for lower respiratory tract
Aspirations
28
Presentation of results for lower repiratory tract
Bartlett's Classification (sputum only)
29
4 cells scanned for their presence in the Bartlett's classification
- squamous epithelial cells (SECs)
- polymorphonuclear neutrophils (PMNs)
- alveolar macrophages (AMs)
- columnar cells (CC)
30
Interpretation of PMNs in Bartlett's classification
Bacterial pneumonia
31
Interpretation of AMs and CCs in Bartlett's classification
Lower respiratory tract specimen was collected properly
32
Interpretation of SECs in Bartlett's classification
Oral flora contamination
33
Describe prurulent secretions
Greater than 25 PMNs and less than 10 SECs per low power field
34
Describe oral secretions
Greater than 25 SECs and less than 10 PMNs per low power field
35
Describe respiratory secretions
Predominance of AMs and CCs (greater than 10 PMNs per low power field)
36
What should be done with prurulent secretions?
Culture the specimen
37
What should be done with oral secretions?
Recollect specimen
38
Specimen for gastrointestinal tract
Rectal swab
39
Infection detected by gastrointestinal tract specimens
Gastroenteritis
40
3 methods of collection for urine
- Clean catch midstream specimen
- catheterized specimen
- suprapubic aspiration
41
Infection detected in urine specimen
Urinary tract infections
42
What is the time limit of refrigeration of urine specimen if there is delay?
Refrigerate not more than 24 hours
43
4 screening tests done before colony count of urine
- Griess test
- Triphenyltetrazolium chloride
- Automated methodologies
- Bac-T-Screen
44
Urine screen test that is a chromophoric test for the presence of organic nitrite compounds
Griess test
45
Urine screen test as a redox indicator; used to indicate cellular respiration
Triphenylbetrazolium Chloride
46
Urine screen test for ATP production
Automated methodologies
47
Calibration of urine inoculating loop
1 uL (0.001 mL) of urine
48
Value for bacteriuria
Values greater than 1.0x10^5 CFU/mL
49
Values considered to be contaminated or may represent cultures taken during periods of recovery from UTI after antibiotics have been initiated
Values between 1.0x10^3 and 1.0x10^5 CFU/mL
50
Unit used in urine colony counting
CFU/mL
51
Most common bacteria in urine
Escherichia coli
52
3 infections detected in blood
- bacteremia
- septicemia
- unexplained shock
53
2 factors that affect positive blood cultures
- stage of the disease
| - collection time
54
Collection time for subacute bacterial endocarditis (SBE)
24-48 hours (3-4 cultures)
55
Collection time for endocarditis
Anytime
56
Collection time for brucellosis
During exacerbation of symptoms or elevation of temperature
57
Collection time for shredding of bacteria in the blood
30-45 mins before the fibrile episode
58
Volume of blood needed from adults
20-30 mL/culture set (10 mL blood/bottle)
59
Volume of blood needed for infants
1-5 mL/culture set
60
3 types of bacteria that will be detected in blood cultures
- aerobic
- anaerobic
- capnophilic
61
Percent of CO2 during areobic or anaerobic incubation of blood culture
5-10% CO2
62
Ideal anticoagulant for blood used in blodd culture
Sodium polyanethol sulfonate (SPS) AKA liquoid
63
What is the time limit for refrigeration of blood sample when there is delay?
Refrigerate for 1-2 hrs
64
3 susbtances used to identify Peptococcus anaerobius, N. gonorrhoeae, and Gardnerella vaginalis
- sodium amylosulfate
- sodium citrate
- osmotic stabilizer (10-30% sucrose)
65
3 bacteria identified using sodium amylosulfate, sodium citrate, and osmotic stabilizer (10-30% sucrose)
- Peptococcus anaerobius
- Neisseria gonorrhoeae
- Gardnerella vaginalis
66
Medium used in blodd culture
Biphasic medium; 1:10 ratio (1 mL blood, 10 mL medium)
67
Blood culture positive result for gram negative rods
Uniformly turbid with gas bubbles
68
Blood culture positive for meningococci and pneumococci
Less distinct turbidity
69
Blood culture positive result for ß-hemolytic streptococci
Cotton ball colonies on top of sedimented red cell with clear upper layer
70
Blood culture positive result for pathogenic species of staphylococci
Large jelly-like coagulum throughout the broth
71
Blood culture positive result for bacillus species and saprophytic fungi (non-pathogenic)
Thick pellicle on the surface of the medium with hemolysis
72
Blood culture positive result for Clostridium species
Marked hemolysis with unpleasant odor and gas under pressure
73
Blood culture positive result for Bacteriodes species
Less gas than Clostridium spp. but a foul odor
74
Blood culture positive result for Haemophilus
No change in medium
75
How long should blood cultures be then declared negative?
After 7 days
76
Incubation period for Brucellosis
21 days
77
Skin contaminants in blood culture
Diphtheroid bacilli
78
4 organisms involved in fatal transfusions
- Pseudomonas (B. anthracis)
- citrobacter
- achromobacter
- late lactose fermenting enteric organisms
79
How is cerebrospinal fluid collected?
Lumbar puncture
80
2 bacteria detected in CSF
- N. meningitidis
- H. influenza
Fastidious bacteria
81
3 transport medium used for specimens with anticipated delay
- Stuart's medium
- Amie's medium
- Cary-Blair medium
82
Transport medium that increases viability of pathogens
Stuart's medium
83
Transport medium that is a substitute for Stuart's medium
Amie's medium
84
Transport medium for stool specimens and enteric pathogens
Cary-Blair medium
85
Specimen for male genital tract
Urethral discharge
86
3 specimens for female genital tract
- uterine cervix
- urethra
- cervix
87
Transport medium for genital tract specimen
Gono-Pak/JEM-BEC
