BACTERIAL INFECTIONS - SEROLOGICAL TESTS FOR SYPHILIS Flashcards
1
Q
- Microscopic due to absence of visualizing agent
A
VDRL
2
Q
- Both a qualitative and quantitative slide flocculation test for serum and spinal fluid (neurosyphilis)
A
VDRL
3
Q
Antigen (reagent) consists:
A
- CARDIOLIPIN (0.03%)
- Lecithin (0.21%)
- Cholesterol (0.9%)
4
Q
Serves as Ag
A
- CARDIOLIPIN (0.03%)
5
Q
Main reacting component
A
- CARDIOLIPIN (0.03%)
6
Q
Neutralize the anti-complementary properties of cardiolipin
A
- Lecithin (0.21%)
7
Q
Increase the reactive surface and complement fixing capacity of cardiolipin
A
- Cholesterol (0.9%)
8
Q
- Unknown is reagin Ab, w/c specifically reacts w/ cardiolipin
A
VDRL
9
Q
Inactivated serum: [?]
A
56°C heat for 30 mins
10
Q
to destroy the complement
A
Inactivated serum
11
Q
Volume of the sample:
A
50 ul
12
Q
Serum:
A
14mm slide with ceramic ring
o 180 rpm for 4 mins
13
Q
Spinal fluid:
A
16 mm in diameter and 1.75mm depth
o 180 rpm for 8 mins
14
Q
- Qualitative Serum VDRL:
A
18-gauge needle without bevel that will deliver 60 drops of antigen suspension per mL; Ring: 14mm
15
Q
- Quantitative Serum VDRL:
A
19-gauge needle without bevel that will deliver 75 drops of antigen suspension per mL; 23-gauge needle that with or without bevel will deliver 100 drops of saline per mL; Ring: 14mm
15
Q
- CSF VDRL:
A
21- or 22-gauge needle that will deliver 100 drops per mL; Ring: 16 mm
16
Q
Macroscopic due to presence of charcoal as visualizing agent
A
RPR
17
Q
Unheated serum
A
RPR
18
Q
Standard test for screening Syphilis
A
RPR
19
Q
RPR Principle:
A
RPR Ag + 1egain (if present) will combine with lipids and coagglutinates with charcoal
20
Q
RPR Endpoint:
A
Flocculation (black clumps)
21
Q
Modified VDRL Ag - reagent
A
RPR
22
Q
- Original VDRL Ag (?)
A
CARDIOLIPIN
23
Q
Main reacting component in RPR
A
CARDIOLIPIN
24
: enhances the ability of the suspension by inhibiting the oxidation of lipids
2. Na2EDTA
25
: visualizing agt
3. CHARCOAL
26
: buffers the suspension
4. PHOSPHATE
27
: preservative
5. THIMEROSAL
28
also inactivates the complement
5. THIMEROSAL
29
: eliminates the need for heating because it inactivates the inhibitors in serum or plasma
6. CHOLINE CHLORIDE
30
Primarily inactivates the complement
6. CHOLINE CHLORIDE
31
FTA-ABS Principle:
Indirect IF test
32
FTA-ABS Unknown:
Ab
33
FTA-ABS Indicator label:
FITC
34
Heat inactivated patient serum reacts with Sorbent consisting of Nonpathogenic treponemes (?)
Reiter strain
35
to remove cross-reactivity
Reiter strain
36
Perform indirect IF using pathogenic strain (?) fixed to slide
Nichols strain
37
FTA-ABS (+) result
(+) Green fluorescence = Presence of Anti-T. pallidum Ab
38
T. pallidum subspecies pallidum causes:
Syphilis
Bejel
Pinta
39
Use [?] to remove crossreactivity to other diseases and confirm syphilis
reiter strain
40
If Anti-T. pallidum Ab is present, it will react with/ [?]
Nichols strain
41
HEMAGGLUTINATION TESTS Principle:
Agglutination
42
RBCs are sensitized with Nichols strain
HEMAGGLUTINATION TESTS
43
HEMAGGLUTINATION TESTS Reactive result:
sooth matte at the bottom of the reaction well
44
HEMAGGLUTINATION TESTS Nonreactive result:
compact button of cells with or without a hole in the center
45
Only performed by reference lab requiring expertise
HEMAGGLUTINATION TESTS
46
1. ТРНА:
Turkey erythrocytes
47
2. МНА-ТР:
Tanned sheep erythrocytes
48
Lyme disease Clinical hallmark:
(chronicum/classic) Erythema migrans (EM)
49
Erythema migrans (EM) characteristics
Bull’s eye rash
Tick burrowing
50
Lyme disease bacterial agent
Borrelia burgdorferi
51
Lyme disease Vector:
Ixodes scapularis tick – reduviid bug
52
MOT: vector-borne
Lyme disease
53
Survives in hot temperature
Ixodes scapularis tick – reduviid bug
54
Resembles signs and symptoms of stroke (facial palsy), gouty arthritis (swollen knee)
Lyme disease
55
Febrile disease – extremely high fever (what temp range?)
>37.5oC or 39 to 40oC
56
Group A Streptococcus agent
Streptococcus pyogenes
57
Streptococcus pyogenes causes:
1. URTI –pharyngitis: main infection
2. Necrotizing fasciitis: flesh-eating bacteria
3. Streptococcal Toxic Shock Syndrome
4. Streptococcal pyoderma (impetigo)
5. Scarlet fever
6. Erysipelas
58
(following infection after main infection)
sequelae
59
Most important sequelae
1. Acute Rheumatic fever
2. Post streptococcal Glomerulonephritis
60
Acute Rheumatic fever
develops as a sequela to pharyngitis or tonsillitis in [?] of infected individuals.
2 to 3 percent
61
Acute Rheumatic fever
period is typically [?] after onset of the sore throat.
1 to 3 weeks
62
Characteristic features of acute rheumatic fever include
fever inflammation in the joints, and inflammation of the heart
63
Acute Rheumatic fever Virulent factor:
M protein
64
attaches itself to heart valves; forms Ab against M protein where it attaches leading to Ag-Ab reaction; attacks the heart
M protein
65
• condition characterized by damage to the glomeruli in the kidney due to the deposition of Ab-streptococcal immune complexes
Post streptococcal Glomerulonephritis
66
Kidneys: filters the blood
Glomerulus - first filtering part
Ag-Ab does not pass thru and accumulates in the glomerulus
Result: Nephritis
Post streptococcal Glomerulonephritis
67
Immunologic Features
1. Lipoteichoic Acid
2. Protein F
3. M Proteins
68
: adheres to epithelial cells ‘
1. Lipoteichoic Acid
69
: adheres to epithelial cells
2. Protein F
70
: anti-phagocytic, mimic proteins on the heart valve
3. M Proteins
71
(Virulence Factors: substances that can produce Abs against)
Immunologic Features
72
Cannot be easily recognized by the immune system
M Proteins
73
Mimics the protein on the heart valve
M Proteins
74
Extracellular products - aka
exoantigens
75
Extracellular products
• Hemolysins (Streptolysin O and S)
• Hyaluronidase
• DNAse
• Streptokinase
• Erythrogenic toxin
76
- spreading factor
Hyaluronidase
77
– exoantigen tested in the sero lab
DNAse
78
causes scarlet fever
Erythrogenic toxin
79
Strawberry tongue
Erythrogenic toxin
80
Ag or Ab
- Reagent
ANTIGEN
81
Ag or Ab
- Unknown in the px
ANTIBODY
82
Whole or processed B. burgdorferi
IFA
83
Anti-Borrelia antibody from patient, antihuman globulin with fluorescent tag
IFA
84
Difficult to perform
IFA
85
Sonicated B. burgdorferi
EIA
86
Anti-Borrelia antibody from patient, antihuman globulin with enzyme tag
EIA
87
Easy to perform
EIA
88
Purified flagellin protein
EIA
89
Antiflagellin antibody from patient, antihuman globulin with enzyme tag
EIA
90
Easy to perform; highly specific; sensitive in early Lyme disease
EIA
91
C6 peptide
EIA
92
Conserved region of surface lipoprotein (VlsE)
EIA
93
Easy to perform; highly specific; initial studies promising; sensitive in early and late Lyme disease
EIA
94
Patient DNA matched to Borrelia DNA
DNA probe
95
Ag: None
DNA probe
96
Technically demanding, very specific; lacks sensitivity
97
ANTISTREPTOLYSIN O TEST (ASTO/ASO) Principle:
based on the neutralization of the hemolytic activity of streptolysin O
98
ANTISTREPTOLYSIN O TEST (ASTO/ASO) Principle in the lab:
Latex Agglutination
99
If a patient's serum containing antistreptolysin O Ab is added to the streptolysin Rgt, an Ag-Ab reaction occurs causing the neutralization of the toxin
ANTISTREPTOLYSIN O TEST (ASTO/ASO)
100
ANTISTREPTOLYSIN O TEST (ASTO/ASO)
Positive result:
Negative result:
Positive result: NO LYSIS
Negative result: Hemolysis
101
Patient serum: w/ anti-SLO Ab
Reagent:
1. SLO
-SLO + anti-SLO = Ag-Ab binding
-SLO rgt will be neutralized
2. RBC (indicator)
-Di papansinin
-(+) Result: No lysis due to presence of anti-SLO Ab
What is the result?
Positive result: NO LYSIS
102
Patient serum: w/o anti-SLO Ab
Reagent:
3. SLO
-No neutralization
-SLO rgt will be hydrolyzed
4. RBC (indicator)
-SLO + RBC = Lyse
-(+) Result: Lysis due to absence of anti-SLO Ab
What is the result?
Negative result: Hemolysis
103
– caused by toxin or SLO
o Dirty purple
104
– caused by complement
o "vin rose" / red lysis
105
What tube is (+) control in ASO?
Tube 13
106
What tube is (-) control in ASO?
Tube 14
107
is the RBC control (no hemolysis)
Tube 13
108
is the SLO control (hemolysis)
Tube 14
109
ASO
Prepare [?] tubes
14
110
ASO Serum Dilution
0.5ml serum + 4.5ml of diluent
111
ASO Normal:
Titer of 166 Todd units or below (0-166)
112
ASO Moderately elevated
-Adult:
-Child:
240 Todd units
320 Todd units
113
o Passive agglutination
ASO Latex Agglutination Slide Method
114
ASO Latex Agglutination Slide Method NV:
<200IU/mL
115
ASO Latex Agglutination Slide Method
(+) Result:
Agglutination
116
ASO Latex Agglutination Slide Method False (+) on px w/
braces
117
ANTI-DNASE B TESTING Principle:
Neutralization
118
ANTI-DNASE B TESTING
If [?] is present, it will neutralize the rgt [?]
Anti-DNAse B Ab
DNASE B
119
ANTI-DNASE B TESTING Positive result:
green complex (Intact DNAmethyl green conjugate because no hydrolysis)
120
ANTI-DNASE B TESTING Negative result:
hydrolysis of the green conjugate to colorless
121
Reagents:
1. DNASE B
2. DNASE B rgt will not be neutralized due to absence of Ab DNAmethyl green
- DNASE B rgt has now the capability to hydrolyze the DNAmethyl green resulting to a colorless cpd
-(-) Result: due to absence of Anti-DNAse B
What is the result?
Positive result: green complex (Intact DNAmethyl green conjugate because no hydrolysis)
122
Reagents:
1. DNASE B = Ag-Ab binding
- DNASE B rgt will be neutralized
2. DNAmethyl green
- Cannot be hydrolysed since it is bound to Ab
What is the result?
Negative result: hydrolysis of the green conjugate to colorless
123
slide agglutination screening test
STREPTOZYME TESTING
124
detection of antibodies to several streptococcal antigens
STREPTOZYME TESTING
125
STREPTOZYME TESTING
Sheep red blood cells are coated with
streptolysin, streptokinase, hyaluronidase, DNase, and NADase
126
STREPTOZYME TESTING
Positive test:
Hemagglutination
127
false positives
IFA
EIA
128
subjective
IFA
129
more sensitive than IFA
EIA
