Septicemia

Question 1

Bacteremia Definition

Answer 1

The presence of bacteria in the blood. Disease may or may not be present.

Question 2

Agents of Septicemia infection

Answer 2

Staph., Strep., Enterococcus, E. coli, Enterobacteriaceae, Yeast

Question 3

Septicemia Definition

Answer 3

Bacteria, or their toxins, are causing harm to the host. Disease is present.

Question 4

Primary Bacteremia

Answer 4

Endovascular source such as infected cardiac valve or intravenous catheter

Question 5

Secondary Bacteremia

Answer 5

Extravascular source such as lungs in pneumonia

Question 6

Classification of Bacteremia by Microbiology

Answer 6

1. G+
2. G-
3. Anaerobic
4. Polymicrobial (enterococci and G- mixture from gut)

Question 7

Classification of bacteremia by place of acquisition

Answer 7

1. Community
2. Nosocomial

Question 8

Classification of Bacteremia by Duration

Answer 8

1. Transient
2. Intermittent
3. Continuous

Question 9

Intermittent Causes of Septicemia

Answer 9

Meningococcemia, gonococcemia, pneumonia

Question 10

Continuous Causes of Septicemia

Answer 10

Endovascular source like endocarditis and infected catheters

Question 11

Intravascular Septicemia

Answer 11

Originating in the cardiovascular(CV) system:

• Infective endocarditis
• Intravenous, catheter-associated

Question 12

Extravascular Septicemia

Answer 12

Originating outside the CV system and entering the bloodstream via lymphatic system.

• GU tract (25%)
• Respiratory tract (20%)
• Abcesses/Surgical wounds (15%)
• Others (35%)

Question 13

Specimen Collection and Transport

Answer 13

• Collect 2-3 specimens per 24 hours
• Specimens collection should not be closer than 3 hrs
• Draw 10 mL from two separate venipuncture sites.
• Specimen should be transported at room temp. within 2 hours

Question 14

Minimum Microbe Presence for Septicemia Diagnosis

Answer 14

Adults: usually

Question 15

Blood Culture Media

Answer 15

Sodium polyanethol sulfonate (SPS 0.03%), the most common anticoagulant used. Maintain a ratio of 1:5 (blood to broth medium)

Question 16

Manual Blood Culture Detection Methods (Conventional)

Answer 16

• Visual inspection
• Blind subculture

Question 17

Manual Blood Culture Detection Methods (Septi-check)

Answer 17

• Biphasic media
• Self-subculturing
• Poor anaerobe recovery

Question 18

Manual Blood Culture Detection Methods (Isolator)

Answer 18

A lysis-centrifugation system

1. Blood lysed by saponin
2. Centrifuged
3. Inoculated directly to media

Question 19

Automated Blood Culture Detection Methods

Answer 19

• Continuous shaking of bottles
• Continuous monitoring for positives (yellow color indicates this)
• Variety of media formulations
• Barcode driven

Question 20

Differentiating Septicemia and Contamination

Answer 20

• Multiple bottles would be positive versus only single bottle in case of a contamination.
• Isolation of same organism in blood and from a sterile site simultaneously.
• Isolation of members of Enterobacteriaceae, S. aureus, P. aeruginosa, S. Pneumoniae, H. influenzae, C. albicans always indicate an infection.
• Most common contaminants are Propionobacterium acnes, diphtheroids and Staphylococcus coagulase-negative species.
• For slow-growers, keep the cultures longer (upto 4 weeks).

Question 21

Rapid Detection of mecA

Answer 21

Oxoid’s RAPID PBP2* TEST, a latex agglutination test Velogen’s cycling probe assay Cepheid’s Smart Cycler assay Advandx PNA FISH