Mod 2 Specimen Collection

Question 1

What type of swab is used to collect specimen for most organisms

Answer 1

Polyester tipped swab on a plastic shaft

Question 2

Swab that should be avoided for collection of viral cultures

Answer 2

Calcium alginate. Inactivates HSV

Question 3

True or false. Specimens for recovery of bacteria should ideally be collected after microbial therapy has started.

Answer 3

False. Before

Question 4

_______ may be toxic to N. gonorrheae

Answer 4

Cotton swab

Question 5

______ shafts should be avoided and may be toxic to C. trachomatis

Answer 5

Wooden shaft swab

Question 6

True or false. Swabs are optimal for detection of anaerobes, mycobacteria or fungi

Answer 6

False.(NOT) optimal

Question 7

Is always superior to a swab specimen for recovery of pathogenic organisms

Answer 7

Tissue sample or fluid aspirate

Question 8

Proper Specimen collection includes:

Answer 8

Specimen obtained at site of infection
Minimal contamination
Collected in sterile container (except stool)
Labeled with name and identification #
Source of specimen
Date and time collected

Question 9

Specimen transport.

Specimen should be placed in:

Answer 9

Biohazard bags

Question 10

Specimen transport.

If a delay happens specimens for detection of C. trachomatis or viruses should be _______ to prevent overgrowth of normal flora

Answer 10

Refrigerated

Question 11

Specimen transport.

If a delay happens specimens for detection of N. gonorrheae should be held at __________

Answer 11

Room temperature. (Refrigeration adversely affects recovery of potential pathogens)

Question 12

Universal precaution:

Should be worn at all times

Answer 12

Gloves and lab coat

Question 13

Universal precaution:

Must be worn when there is risk of splashing droplet formation

Answer 13

Gloves + lab coat

Mask, goggles,gowns/apron

Question 14

True or false. Mycobacteria or fungi should be opened in a biological safety cabinet?

Answer 14

True. To prevent contamination of cell cultures

Question 15

Essential in identifying bacteria responsible for bacteremia, sepsis, infections of prosthetic valves etc.

Answer 15

Culture of blood

Question 16

Blood should be collected for culture before anti microbial therapy when any one or a combination are present:

Answer 16

Fever 38 C or greater
Hypothermia 36 c or lower
Leucocytosis
Granulocytopenia
Hypotension

Question 17

Germane to the detection of microorganisms in the blood

Technique for specimen collection

Answer 17

Phlebotomy

Question 18

True or false. The optimal time to draw blood for cultures when bacteremia or fungemia is suspected is just after a chill?

Answer 18

False. Before chills

However because it is not predictable, blood cultures are collected after the onset of fever and chills

Question 19

True or false. In adults with bacteremia, the number of CFU (colony forming units) per ml is frequently low at (20-30 ml per culture set) compared to infants and children where concentration is higher with (1-5 ml of blood per culture)?

Answer 19

True

Question 20

Nature of bacteremia:

Manipulation of a focus of infection (abscess, furuncle, cellulitis)

Surgical procedures

Localized infections like pneumonia

Answer 20

Transient Bacteremia

Question 21

Nature of bacteremia:

Undrained abscess

Answer 21

Intermittent bacteremia

Question 22

Nature of bacteremia:

Hallmark of intravascular infection

Answer 22

Continuous bacteremia

Question 23

Manual blood cultures:

Consist of broth medium in a bottle to which a chamber containing agar media on a paddle is attached

Recovery of facultative bacteria and yeast

Answer 23

Biphasic system

Question 24

Manual blood cultures:

Inhibit coagulation and the complement cascade, lyse blood cells and provide a cushion for microorganism during centrifugation

Answer 24

Lysis centrifugation blood culture system

Question 25

Automated blood culture systems: Enhances recovery of fungi and recovery of bacteria from pts receiving anti microbial agents Color changes are monitored every 10 minutes ( change in color from green to yellow)

Answer 25

Colorimetric detection of Co2

Question 26

Automated blood culture systems: Computer generates growth curves and data are analyzed according to growth algorithms.

Answer 26

Fluorescent technology

Question 27

Detection of positive cultures: Detected within 12-36 hrs of incubation

Answer 27

Aerobic organisms

Question 28

Detection of positive cultures: Identification and susceptibility results 24-48 hours after gram staining

Answer 28

Aerobic organisms

Question 29

Detection of positive cultures: Not detected for 48-72 hrs and identification is not available for 3-4 days after that

Answer 29

Anaerobic organisms

Question 30

Detection of positive cultures: Not detected until 3-5 days

Answer 30

HACEK group ``` Haemophilus Actinobacillus Cardiobacterium Eikenella Kingella ```

Question 31

Detection of viruses like HIV, HCV and HBV to antiviral therapy using:

Answer 31

Quantitative PCR

Question 32

Detection of parasites: Simplest technique Diagnosis of trypanosomiasis or filariasis

Answer 32

Direct mount

Question 33

Detection of parasites: Standard preparation for determining species of plasmodium, babesia, trypanosoma and microfilaria

Answer 33

Thin smear

Question 34

Detection of parasites: Detects all parasites + minimum lab work up for their diagnosis Giemsa stain, allowed to dry for dehemoglobinization

Answer 34

Thick smears

Question 35

It is collected to diagnose meningitis

Answer 35

CSF

Question 36

Agents most commonly responsible for meningitis

Answer 36

Enteroviruses

Question 37

CSF is usually obtained by_______ or is aspirated from the _______ or collected from a ______.

Answer 37

Lumbar spinal puncture Ventricles Shunt

Question 38

Test performed on fluid (CSF):

Answer 38

Tube 1: protein and glucose Tube 2: prep smears to stain with gram stain for culture Tube 3: cell counts Tube 4: special tests (cryptococcal antigen)

Question 39

Diagnosis of neurosyphillis based on findings:

Answer 39

Pleocytosis Elevated protein concentration Positive VDRL

Question 40

Used most often for diagnosis if viral infections of the CNS

Answer 40

Nucleic acid amplification tests

Question 41

Cultures of free living amoebas from CSF are done on _______ plates covered with a suspension of E. Coli

Answer 41

Non nutrient agar plates

Question 42

Fluid is collected from the pericardial, thoracic, or peritoneal cavity or from joint spaces by:

Answer 42

Aspirating with a needle and syringe

Question 43

Most common causes of infectious pericarditis

Answer 43

Enteroviruses ( Cox viruses A and B)

Question 44

The fluid collected in a hydatid cysts specimen is usually:

Answer 44

Clear and contains hydatid sand

Question 45

True or false. Surgeon must obtain an amount of material that is adequate for both histopathologic and microbiological examination of tissues.

Answer 45

True

Question 46

Tissue obtained surgically should be obtained into a:

Answer 46

Sterile, wide mouthed, screw capped container