5. Anti-streptolysin O

Question 1

Characteristics of streptococcal infection?

Answer 1

Gram + cocci chains

Non motile

No spore forming

Facultative anaerobe

Question 2

Streptococcal infection but gaseous requirements is obligate anerobe?

Answer 2

Peptostreptococci

Question 3

Group A Streptococci?

Answer 3

S. pyogenes

Question 4

Virulence factor that is associated with hyaluronic capsule; pharyngitis

Answer 4

M proteins

Question 5

Virulence factor that induce TNF alpha and IL-1 beta?

Answer 5

Streptolysin S

Question 6

MOT of S. pyogenes?

Answer 6

Direct contact to respiratory droplets

fomites

Question 7

Clinical infection?

Answer 7

Strep throat
Scarlet fever
Pyodermal infection
Necrotizing fasciitis
Streptococcal Toxic shock syndrome
Acute rheumatic fever

Post streptococcal glomerulonephritis

Question 8

detect antibodies to streptolysin O enzyme

Answer 8

Anti-streptolysin O

Question 9

Recent streptococcal infections from patients suspected of having acute rheumatic fever and

post-streptococcal glomerulonephritis following a throat infection

Indication of?

Answer 9

streptolysin O

Question 10

Hemolytic method for lab diag of streptolysin O?

Answer 10

ASO classic procedure

Question 11

PRocedure for ASO classic procedure?

Answer 11

Dilute serum
Add SLO reagent
Incubate
Add RBC indicator

Question 12

How do you report ASO classic procedure?

Answer 12

Titer with no hemolysis in Todd unit

Question 13

What is considered moderately elevated in ASO classic procedure for young adults?

Answer 13

240 Todd Unit

Question 14

What is considered moderately elevated in ASO classic procedure for Child?

Answer 14

320 Todd Unit

Question 15

What is the limitations for ASO Classic procedure?

Answer 15

Streptolysin reagent and RBC reagent are not stable

Question 16

What is the alternative or to make up the limitations for ASO classic procedure?

Answer 16

Nephelometry

Question 17

What is the unit for Nephelometry?

Answer 17

International Unit

Question 18

When will the Streptolysin O increase after infection?

Answer 18

1 to 2 weeks

Question 19

When will Streptolysin O peak following the symptoms?

Answer 19

3 to 6 weeks

Question 20

Percentage of antibody response to acute rheumatic fever

Answer 20

85%

Question 21

Is ASO titers helpful in individuals with skin infections?

Answer 21

False

Question 22

Why ASO titers is not use in skin infections?

Answer 22

Streptolysin O is not high in skin infection

Question 23

Procedure for ASO Latex test kit?

Answer 23

Latex particle w/SLO + serum

Question 24

What is the positive indicator for ASO latex test kit?

Answer 24

Agglutination

Question 25

Normal value for ASO latex test kit?

Answer 25

Less than or equal to 200 IU/mL

Question 26

Which of the following is not part of the preparation of Assay? A.) Allow all reagents and samples to warm to room temp after use B.) Gently mix the reagents before use; Avoid foaming C.) Gently Mix the latex reagent before each use to ensure homogeneity

Answer 26

A. Should be "Before" use not after

Question 27

Which of the following is not part of the Qualitative procedure? A.) Bring all reagents and specimens to cold temp B.) Place one drop (50uL) of the positive control and Negative control and 50 uL of the Patient serum into separate circles on the glass slide C.) Shake the ASO latex reagent gently and add 2 drop on each circle next to the sample to be tested and control D.) Mix well using a disposable stirrer spreading the mixture over the whole test area and tilting the slide gently. E.) Agitate for about 5 minutes with the rotator or by hand and observe

Answer 27

A.) should be room temp C.) One drop (ALL One drop in this procedure) E.) Agitate for about 2 minutes

Question 28

What is the dilution factor for Semi-quantitative procedure?

Answer 28

1:2 (2)

Question 29

What is the composition for Semi-Quantitative procedure?

Answer 29

0.25 mL serum/tube + 0.25 mL of saline (ALL 0.25 mL)

Question 30

Which of the following is not part of the Semi Quantitative procedure? A.) Serum to be titrated is serially diluted in 0.9g/L B.) Place on drop of positive and negative on slide C.) Dilute the control D.) Place 1 drop (50uL) of each serum dilution individually in successive circles on the slide

Answer 30

C.) Never dilute control

Question 31

True or False The serum ASO titer can be defined as the highest dilution showing a positive result

Answer 31

TRUE

Question 32

Formula for Approximate ASO level (IU/mL)

Answer 32

ASO titre = Highest dilution with positive reaction X Reagent sensitivity (200 IU/mL)