Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Clinical Laboratory Science > Clincal Microbiology > Flashcards

Clincal Microbiology Flashcards

1
Q

What are the characteristics of bacteria

A

Multiply by fission
Form colonies
Bacteria morphology

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Bacteria Shapes

A

Coccus
Bacillus
Spirochetes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Types of Gram stains

A

Gram positive appear blue-purple,
gram negative appear pink-red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Growth requirements

A

Medium provides nutrients for growing
microorganisms
○ Bacteria that can only grow on
specialized medium are fastidious
bacteria
○ Aerobic and anaerobic bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is Pathogens

A

bacteria that
cause disease through
infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is communicable disease

A

Diseases that spread from
person

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Normal flora

A

bacteria
that are natural inhabitants
of the human body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Opportunistic pathogens

A

invade the body only
when immune defenses are
impaired

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Bacteriological Procedures

A

Specimen collection
- Bacteria collected
- Find growth of
bacteria on a medium that
provides nutrients
Identifying bacteria
- can use Microscopic morphology, colony
appearance, reactions with Gram
stain, growth on media,
biochemical reactions, gene
probes, antibody reactions
Antibiotic susceptibility testing
- Find minimum inhibitory
concentration (MIC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Reasons for Ordering Cultures

A

bad Throat
- Sore throat, fever, negative
rapid strep test

bad Nasal
- B Pertussis, MRSA,
rhinovirus, flu, RSV

bad Urine
- Recurring UTIs

bad Sputum
- Prolonged cough, fever, lung
infection, TB, pneumonia

bad Stool
- Diarrhea with blood and mucous,
prolonged bout of diarrhea
Signs of intestinal infection,
Salmonella, E. coli

bad Blood
- Suspected sepsis or
septicemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

throat culture

A

If negative for rapid test for strep throat, perform throat culture
● Sterile swab should be touched to tonsils or pharyngeal surfaces; tongue and
mouth will contaminate swab
● Streak immediately on blood agar plate if available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Nasal Culture

A

Nasopharyngeal swabs with flexible shafts, moistened with sterile saline; one
swab for each nasal cavity
● Swab inserted into anterior nostril 2 cm and rotated gently against nasal mucosa
● No rayon/Dacron swabs because they kill target organisms
● If pertussis (whooping cough) suspected, calcium alginate swab used with
Regan-Lowe medium transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Urine Culture

A

Clean-catch collected in sterile container
● If urine can’t be cultured within an hour after collection, use sterile tube such as
BD Urine C&S Transport kit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Sputum Culture

A

Sputum is material coughed up from lungs and is examined to aid in diagnosis
of lower respiratory tract infection
● Collection instructions
○ Rinse mouth
○ Collect 2 separate specimens in sterile containers, such as BD Sputum
Collection System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Stool Culture

A

One specimen per day collected on 3 consecutive days
● 3 vials that contain medium such as Cary Blair or Amies
● Para-Pak vials for culture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Blood Culture

A

Collected by venipuncture; site must be cleansed first with alcohol then with a swab
containing 2% solution of tincture of iodine
● In order of draw, blood culture bottles are filled first; 2 bottles usually collected, aerobic bottle
filled first
● Bactec instrument inoculated blood cultures and senses changes in CO2, which is released as
microorganisms grow; smear of blood from positive bottle can be made and Gram-stained to
determine microorganism present
● Trek Diagnostic ESP EZ Draw draws 0.1 mL of blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Aseptic technique

A

set of procedures used to prevent spread of infection during surgical
procedures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Aseptic technique (physical)

A

○ Protective clothing
○ Fluid-resistant lab coat
○ Disposable lab coats/gowns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Microbiological safety cabinets

A

Class I – protect worker and environment but not culture
Class II – provide protection to worker, environment, and culture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Disinfectants and antiseptics

A

Disinfectants are chemicals used to kill/control growth of microorganisms or inanimate objects
Bactericidal – kill bacteria
Bacteriostatic – slow growth of bacteria
Antiseptics are chemicals used to control growth of microorganisms on living tissue
Sterilization frees an article or area from all living organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Agar

A

derivative of seaweed used to solidify liquid
media, which grows and isolates bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Primary medium

A

first inoculated with
specimen collected from patient
○ Most common is blood agar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Enriched medium

A

supports growth of
wide variety of organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Selective media

A

ingredients that inhibit the
growth of certain microorganisms while allowing the
growth of others

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Indicator medium

A

detects metabolic activity of
particular microorganisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Inoculation

A

Process of transferring microorganisms to a growth medium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How to do swab agar plate

A

Gently roll specimen swab onto one quadrant of agar plate, then prep bacterial smear by
rolling swab across sterile glass slide
○ Inoculating loop spreads inoculated material over agar plate to produce isolated colonies
○ Accomplished by streaking 4 quadrants, decreasing amount of culture material as
streaking proceeds into each quadrant
○ Loop Is sterilized and cooled to spread material into each quadrant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Incubation

A

Usually kept in 35-37 C
incubator
● Plates are inverted to
prevent formation of
condensate inside lid
● For aerobic specimens,
keep lid open a little bit
and incubate in aerobic
incubator (ambient air)
● Pathogens that grow in
CO2 are kept in CO2
incubator with 5-10% CO2
● Anaerobic specimens can
be incubated in sealed
bags/containers

29
Q

What to do after Observation After 24 Hours

A

Growth on blood agar should be observed for hemolysis, the lysis of RBCs by bacteria
growing on blood agar

30
Q

Beta hemolysis

A

completely lyses blood cells and makes surrounding area transparent

31
Q

Alpha hemolysis

A

incompletely lyses RBCs and makes area green

32
Q

how to do Gram stain

A

○Primary stain
■ Crystal violet poured on slide
■ All bacteria stain purple
○ Gram’s iodine
■ Gram’s iodine, a mordant, allows
dye to adhere
■ All bacteria remain purple
○ Decolorizer
■ Alcohol added briefly to slide when
it is tilted downward at 30 degrees
■ Gram-negative bacteria will be
colorless
○ Counterstain
■ Slide flooded with counterstain
safranin
■ Gram-negative bacteria turn pink

33
Q

Performing the Throat Culture

A

Collecting the specimen
○ Pharyngeal surfaces swabbed with sterile
Dacron/rayon swab; passed across surfaces
of both tonsils or surfaces of fossae and
back of throat
○ Don’t touch tongue or inside of mouth
● Inoculating the media
○ Throat swab immediately used to
inoculate a quadrant of the blood agar
plate
○ Paper disk with antibiotic bacitracin can
be placed on concentrated streak in 1st
quadrant
● Incubating the culture
○ CO2 concentration of 10%
● Reading throat culture plate
○ Beta hemolysis should show up in stabs
○ Presence of zone of inhibition around
bacitracin disk and presence of
beta-hemolytic colonies shows Group A
Strep

34
Q

Why are urine cultures collected?

A

Culture requested when patient
has UTI symptoms

35
Q

What contributes to STDs?

A

Escherichia coli - gram-negative rod part of flora of
intestinal tract

36
Q

How to perform urine culture

A

Clean-catch; must be inoculated within 1 hour of collection. Put into a blood agar. Inhibit growth of gram-positive so gram neg grows. Incubate at 35-37 degrees. Colony color, and hemolysis should be noted. Count of 100 000/mL or greater is evidence of UTI

37
Q

What are some common gram positive bacteria

A

Staphylococcus and Streptococcus

38
Q

Staphylococcus

A

Large, white or yellow
○ On Gram stain, appear spherical and in grape-like clusters

39
Q

Streptococci

A

Small, colorless
○ Spherical, chains or pairs

40
Q

Catalase test

A

used to perform on gram positive. staph is positive and strep negative

41
Q

Coagulase test

A

can differentiate between Staph aureus and other
staph

42
Q

Identification of Gram-negative Bacteria

A

Klebsiella form bubblegum pink, mucoid colonies. Gram negative bacteria will grow on EMB and MAC. Reported as gram-negative rods, coliform by EMB, where coliform refers to intestinal bacteria

43
Q

Antibiotic Susceptibility Tests

A

Tests which antibody works against certain viruses

44
Q

Minimum inhibitory concentration (MIC)

A

Instruments perform bacterial identification. Swab bacteria on an agar plate and put antibodies in each section of an agar plate. The antibody that works the best when it has a circle around the antibody

45
Q

vaginitis,

A

an infection of vagina

46
Q

Common microorganisms in vaginitis

A

Gardnerella vaginalis, Mobiluncus species, Streptococcus
group B, Chlamydia trachomatis, Neisseria gonorrhoeae, the protozoan
Trichomonas and the yeast Candida albicans

47
Q

waht is Saline wet mount prep

A

Mix drop of vaginal specimen with drop of 0.85%
saline on slide

48
Q

KOH prep of vaginal secretions for yeasts and fungi

A

2 drops vaginal material with 1 drop 10% KOH
solution
■ Fungal elements appear as hairs or threads

49
Q

Gram stain of endocervical secretions of bacteria and
yeasts

A

G Vaginalis is gram-variable; scattered over
constituents of smear
■ Yeast stains dark purple
■ Examined for N gonorrhoeae, which causes
gonorrhea; gram-negative, kidney bean-shaped

50
Q

urethritis

A

an inflammation of urethra

51
Q

If midstream urine contains RBCs, bacteria,
WBCS, or protein,?

A

then patient may have UTI
instead of STD

52
Q

how to do Urethral culture

A

Urethral discharge collected using urogenital
swab and cultured for gonorrhea
○ Inoculated on MTM plate to identify
gonorrhea

53
Q

what does a Urethral gram stain do

A

Examined for WBCs and bacteria

54
Q

Identification
of Gonorrhea

A

N. gonorrhoeae appear as tiny,
shiny, grayish colonies growing
along steak pattern. Oxidase test can be used to aid in
identifying colonies, which is
positive. Purple-black color forms when
oxidase-positive colonies are
exposed to reagent

55
Q

Types of herpes

A

Herpes simplex virus, type 1 (HSV-1)
is responsible for cases of oral
herpes and herpes simplex virus, type 2 (HSV-2) causes genital
herpes

56
Q

Identification of
Herpes (HSV)

A

If herpes lesion present, vesicle can
be broken with swab or needle and
fluid collected with swab, which is
then sent to lab for culture
● Serum titers of IgG and IgM can
also be measured

57
Q

Identification of
Chlamydia

A

Caused by C. trachomatis
● DNA probes use specific nucleic
acids, called probe DNA, that is
added to patient specimen; if
patient is positive,
color/luminescence is produced
● In females, Chlamydia can cause
cervix to bleed easily, cervix said to
be friable

58
Q

Identification of
Syphilis

A

Syphilis is venereal disease caused by
Treponema pallidum, a spirochete, or spiral
bacteria
● Primary syphilis characterized by skin lesions,
organ/tissue damage in secondary stage,
cardiovascular/CNS affected in late-stage
● Patient with T. pallidum produces non-specific
antibodies called reagin; RPR (rapid plasma
reagin) test has carbon-containing cardiolipin
antigen that reacts with reagin; also flocculation
test

59
Q

How do pandemics
re-emerge and spread?

A

Environmental Change
Population concentrations
international FLights
Public health
Pathogen adaptation
Natural disasters

60
Q

West Nile Virus

A

In 2002, it caused largest WNV epidemic and animal epizootic ever reported, with 4000 human
cases and 284 deaths in the US
● Normally transmitted by mosquitoes

61
Q

West Nile Virus Symptoms

A

fever, hemorrhaging caused by organ damage

62
Q

waht are Viral Hemorrhagic Fevers

A

Symptoms: fever, hemorrhaging caused by organ damage
● Caused by RNA viruses in 4 families: arenaviruses, filoviruses,
bunyaviruses, flaviviruses

63
Q

What are examples of Viral Hemorrhagic Fevers

A

Rift Valley Fever
Ebola and Marburg viruses
Severe Acute Respiratory Syndrome
Avian influenza

64
Q

Rift Valley Fever

A

Rift Valley fever occurs in livestock and humans in Africa
○ Caused by virus of Bunyaviridae family and transmitted by
mosquitoes

65
Q

Ebola and Marburg viruses

A

Ebola and Marburg viruses are filoviruses that cause high
mortality
○ WHO documented 17 outbreaks in humans

66
Q

Severe Acute Respiratory Syndrome

A

Mycobacterium tuberculosis causes tuberculosis
○ As HIV has increased worldwide, incidence of TB has also
increased

67
Q

Avian influenza

A

Reservoir for influenza A are birds
○ Outbreak in May 2006 in Indonesia was possible pandemic

68
Q

What are biological weapons?

A

Diseases used againest peopl in war

69
Q
A

Clinical Laboratory Science (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions