MICROBIO W1-DAY2_ALN Flashcards
(138 cards)
1
Q
most effective method of sterilization
A
autoclave
2
Q
autoclaving of media and instruments is set at:
A
121C, 15 psi for 15 mins
3
Q
autoclaving of infectious medical waste
A
132C (270F) for 30-60 mns
4
Q
QC for autoclave
A
Bacillus stearothermophilus
5
Q
sterilizer used in tyndallization
A
Arnold’s sterilizer
6
Q
Tyndallization = flowing steam set at:
A
100C for 30 mns for 3 successive days
7
Q
In tyndallization, flowing steam is set for 3 consecutive days. Indicate the purpose of each day.
A
1: killing of vegetative cells
2: germinating spores
3: remaining spores and vegetative cells
8
Q
“thickening through evaporation”
A
Inspissation
9
Q
Inspissation is set at:
A
75-80C for 2 hours, 3 consecutive days
10
Q
used to sterilize inoculating loops and needles
A
Flame
11
Q
Killing principle/mechanism of dry heat
A
via oxidation
12
Q
Usage of oven for sterilization is set at:
A
160-180 for 1.5-3 hrs
13
Q
Biological indicator for QC of ovens
A
Bacillus subtilis
14
Q
this is the most common method of treating infectious waste
A
Incineration
15
Q
Incineration temp
A
870-980C
16
Q
Safest method to ensure that no infective materials remain in samples or containers upon disposal
A
Incineration
17
Q
Methods of culture media sterilization
A
Autoclave
Membrane filtration
18
Q
T/F:
Evacuated tubes should be sterilized via autoclave and ethylene oxide gas
A
FALSE
This can alter pressure inside the tubes
19
Q
The most effective filter used for sterilization via filtration
A
Asbestos - Sietz (98% effective)
20
Q
Millipore size that equates to 100% bacterial sterility
A
0.22 um
21
Q
Sterilization method of choice for antibiotic solutions, toxic chemicals, radioisotopes, vaccines, and carbohydrates
A
Filtration
22
Q
Pertained to as filtrable agents of infection
A
Viruses
Filter: 0.22 um
Virus size: 0.01-0.03 um
23
Q
In filtration, filtration of liquids is accomplished by pulling the solution through ___________ membrane with a vacuum
A
cellulose acetate
cellulose nitrate
24
Q
Used to filter air
A
High-efficiency particulate air (HEPA) filter
removes organisms >0.3 um
25
Sterilization method of choice for syringes, catheter, gloves, and evacuated tubes
Ionizing radiation
26
Sterilization method involving high energy gamma rays
Ionizing radiation
27
Most common chemical sterilant
Ethylene oxide
28
Ethylene oxide biological indicator for QC
Bacillus subtilis
29
"cold sterilization"
ethylene oxide
glutaraldehyde
peracetic acid
30
This sterilization method kills spores in 3-10 hrs and is used for medical equipment (e.g., bronchoscopes) because it does not corrode lenses, metal, or rubber
glutaraldehyde
31
Sterilization method effective in the presence of organic material
Peracetic acid
32
The process that destroys pathogenic organisms, but not necessarily all microorganisms or spores
Disinfecition
33
Sterilization via boiling is set at what temp & duration
100C for 15 mns
34
This sterilization method is used mostly in food industry to prevent food spoilage
Pasteurization
35
Two methods by which pasteurization may be done
Batch method (Low-temp holding)
Flash method (High temp, short-time)
36
Batch method is set at:
63C for 30 mns
37
Flash method is set at:
72C for 15 secs
38
An example of this sterilization method is the use of mercury lamps (long wavelength, low energy)
Non-ionizing radiation
39
Disinfectants used on living tissue are termed:
Antiseptics
40
This destroys vegetative forms on inanimate objects (microbicidal)
Disinfectants
41
Alcohol concentration for disinfection
70%
increased water conc = for protein denaturation
42
Conc. of formaldehyde as disinfectant
8%
43
Conc. of glutaraldehyde as disinfectant
2%
44
Examples of halogens used as disinfectant
Iodine
Chloride
45
How long must iodine be applied to skin
60 secs
46
Iodine + detergent = ?
Iodophor
47
Used to neutralize chlorine (e.g., in pools)
Sodium thiosulfate
48
Bleach is also known as:
Sodium hypochlorite
49
How long before halogens inactive HBV?
10 mns
50
How long before halogens inactivate HIV?
2 mns
51
Common bleach dilution
1:10
1 part NaOCl, 9 parts H2O
52
Metal that is known as algicide
COpper
53
Eye drop solution containing ________ is used to prevent Opthalmia neonatorium
1% AgNO3
54
use of QUATS should be avoided in labs handling what type of microorganism?
MTB
55
Prior to culture of MTB specimens, ________ is used for decontamination to remove normal flora
QUATS
56
Benzalkonium chloride (zephiran) is under what category of disinfectant
QUATS
57
This is sued to disinfect bench tops or other surfaces in the lab and is rapidly inactivated by organic matter
QUATS
58
Standard disinfectant
Phenol
(denature proteins, disrupt cell membranes)
59
Phenol coefficient control for Gram + orgaisms
S. aureus
60
Phenol coefficient control for Gram - organisms
S. typhi
61
Expression of the bactericidal power of a particular substance as compared to pure phenol
Phenol coefficient
62
PC that indicates disinfectant is better than phenol
>1
63
Ionizing radiation biological indicator for QC:
Bacillus pumilus
64
Dry heat oven biological indicator for QC:
Bacillus subtilis var. niger
65
Ethylene oxide biological indicator for QC:
B. subtilis var. globigii
66
Most common type fo BSC
Type II
67
Type of BSC used when radioisotopes, toxic chemicals, or carcinogens will be used
IIB
68
BSC with no recirculation
IIB2
69
BSC with the highest level of safety
Type III
70
Airborne microorganisms
Measles, varicella, TB, smallpox
71
Multi-drug resistant bacteria that is transmitted via contact
Clostridium difficile
72
JEMBEC system type of transport is used for what microorganism
N. gonorrhoeae
73
This substance is added to Stuart's or Amie's media to absorb FA present in the specimen
charcoal
74
Addition of charcoal to Stuart's or Amie's media is for what organisms
N. gonorrhoeae
Bordetella pertussis
75
SPS is used at what concentration as anticoagulant in clinical specimens?
0.025%
76
Long term storage of tissues or other specimens
-70C
77
Storage of serum for serologic studies
Frozen up to 1 week at -20C
78
Storage of normal specimens (urine, stool, viral specimens, swabs, catheters)
4C
79
Example of a critical value in Microbio is presence of what specimen in sterile site?
S. pyogenes
80
Example of a critical value in Microbio is presence of what specimen in genital site of pregnant woman at term?
S. agalactiae
HSV
81
Examples of significant pathogens (considered critical value in microbio)
Bordetella pertussis
Brucella spp.
Legionella spp.
82
In collection of abscess (wound), this substance is added if smear suggests mixed gram positive and gram negative flora
CNA (Columbia Colistin-Nalidixic medium)
83
Addition of CNA in abscess collection enhances growth of what organism
Gram +
84
For collection of deep abscess, (aerobic/anaerobic) transporter is used.
Anaerobic
85
In collection of blood or bone marrow aspirate, collection should be done at time of what type of episode?
Febrile
86
In collection of blood for blood culture, what is the volume for adults and infant px?
adult: >/= 20 mL/set
infants: 1-5 or 1-20 mL/set
87
Ratio of blood to medium for blood cultures
1:10
88
Best concentration of SPS for anticoagulation
0.025 to 0.030%
89
Most common concentration of SPS for anticoagulation
0.025-0.050%
90
Spx of choice for B. pertussis
Nasopharyngeal swab
91
NPS transportation to the lab should be:
<2 hrs/RT
92
Specimen recovered from NPS
H. influenzae
N. meningitidis
B. pertussis
MRSA
93
Bartlets criteria of acceptable sputum sample
<10 EC/LPF
>25 PMNS/LPF
94
When testing for sputum, what spx is used for bedridden px
Gastric lavage
95
Specimen of choice for detecting nontuberculous mycobacteria and other opportunistic pathogens in px with immune dysfunction
Bronchial lavage, washings, and brushings
96
Spx of choice for mechanically ventilated adult px
Endotracheal aspirate (ETAs)
97
Sp. of choice for P. jiroveci/P. carinii testing
BAL
98
common causes of respiratory infection among immunosuppressed
P. jiroveci
P. carinii
99
Factor used for 1 uL inoculated loop in urine colony count
1000
100
Factor used for 10 uL inoculated loop in urine colony count
100
101
volume discarded in using catheter for urine collection
first 15 mL
102
Collection of urine for px with indwelling catheter
aspirate 5-10 mL of urine with needle and syringe
103
Specimen of choice for urine anaerobic culture
Suprapubic aspiration
104
Colony count that means patient has UTI?
> / = 100,000 CFU/mL
105
UTI cause in 90% of cases
E. coli
106
commonc cause of UTI among young females
S. saprophyticus
107
medium used for stool culture
Cary blair
108
common cause of diarrhea and gastroenteritis among children
Rotavirus
109
common cause of diarrhea among adults (Norwalk virus)
Norovirus
110
common cause of diarrhea among hospitalized px
antibiotic-assoc. diarrhea
C. difficile
111
ecofriendly fixative for O & P
PVA
112
Stool specimens containing these substances ar eunacceptable
MABBAN
Mineral oil
Antibiotic
Barium
Bismuth
Antimalarial agents
Non-absorbable antidiarrheal prep
113
How long before specimen be collected after antibiotic/barium administration?
5-10 days
or at least 2 weeks
114
Plating media for routine CSF analysis
BAP
CAP
115
Plating media for CSF analysis (shunt)
BAP
CAP
THIOL
116
CSF must be transported in the laboratory within:
15 mns
117
CSF storage conditions
<24 hrs incubate at 37C
EXCEPT VIRUSES: 4C for 3 days
118
Agent that causes increased eosinophils in CSF (fungal)
Coccidioides immitis
119
causative agent of bacterial meningitis in newborns - 1 month
S. agalactiae and Gram -
120
causative agent of bacterial meningitis in 1 month - 5 yo
H. influenzae (serotype b)
121
causative agent of bacterial meningitis in in 5 yo to 29 yo
N. meningitidis
122
causative agent of bacterial meningitis in >29 yo
S. pneumoniae
123
causative agent of bacterial meningitis in in infants, and immunosuppressed px
L. monocytogenes
124
Type of meningitis associated with normal lactate and glucose level
Viral
125
Type of meningitis associated with pellicle formation
Tubercular
126
Type of meningitis associated with increased WBC primarily neutrophils in CSF
Bacterial
127
Type of meningitis associated with positive limulus lysate test
Bacterial
128
Limulus lysate test rgt
Blood of horseshoe crab (limulus polyphemus)
129
+ rxn in limulus lysate test
clumping
130
Pellicle formation in tubercular meningitis can only be seen at what condition?
overnight refrigeration
131
most common cause of aseptic meningitis
Enterovirus
(no growth of fungi and bacteria upon culture)
132
resemble lymphocytes in CSF
C. neoformans
133
resemble myelin globules in sputum
Blastomyces
134
C. neoformans pattern in gram stain
classic starburst
135
In fungal meningitis, this is the causative agent that shows positive rxn in india ink
C. neoformans
136
Interference in latex agglutination for C. neoformans
Rheumatoid factor
Note: can be eliminated by boiling for 5 mns
137
CSF collection tubes:
Test for each tube?
1. Chem/Sero (frozen)
2. Microbio (RT/37C)
3. Hema/cell count (refrigerated)
4. Microbio
138
If only 1 tube of CSF collected, what is the order of priority of tests?
1. Microbio
2. Hema
3. Chem
