Anti-streptolysin O: Difference between revisions
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{{Short description|Antibody against streptolysin O}} |
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'''Anti-streptolysin O''' (ASO or ASLO) is the antibody made against [[streptolysin|streptolysin O]], an immunogenic, oxygen-labile |
'''Anti-streptolysin O''' (ASO or ASLO) is the antibody made against [[streptolysin|streptolysin O]], an immunogenic, oxygen-labile [[streptococcal]] [[hemolytic]] [[exotoxin]] produced by most strains of group A and many strains of groups C and G ''[[Streptococcus]]'' bacteria. The "O" in the name stands for ''oxygen-labile''; the other related toxin being oxygen-stable streptolysin-S. The main function of streptolysin O is to cause hemolysis (the breaking open of red blood cells)—in particular, [[Hemolysis (microbiology)#Beta|beta-hemolysis]]. |
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Increased levels of ASO titre in the blood could |
Increased levels of ASO titre in the blood could cause damage to the heart and joints. In most cases, penicillin is used to treat patients with increased levels of ASO titre. |
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In most cases, penicillin is used to treat patients with increased levels of aso titre. |
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== Clinical significance == |
== Clinical significance == |
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When the body is infected with streptococci, it produces [[antibodies]] against the various [[antigen]]s that the streptococci produce. ASO is one such antibody. A raised or rising levels can indicate past or present infection. Historically it was one of the first bacterial markers used for diagnosis and follow up of [[rheumatic fever]] or [[scarlet fever]]. Its importance in this regard has not diminished.{{citation needed|date=September 2020}} |
When the body is infected with streptococci, it produces [[antibodies]] against the various [[antigen]]s that the streptococci produce. ASO is one such antibody. A raised or rising levels can indicate past or present infection. Historically it was one of the first bacterial markers used for diagnosis and follow up of [[rheumatic fever]] or [[scarlet fever]]. Its importance in this regard has not diminished.{{citation needed|date=September 2020}} |
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Since these antibodies are produced as a delayed antibody reaction to the above-mentioned bacteria, there is no normal value. The presence of these antibodies indicates an exposure to these bacteria. However, as many people are exposed to these bacteria and remain asymptomatic, the mere presence of ASO does not indicate disease. |
Since these antibodies are produced as a delayed antibody reaction to the above-mentioned bacteria, there is no normal value. The presence of these antibodies indicates an exposure to these bacteria. However, as many people are exposed to these bacteria and remain asymptomatic, the mere presence of ASO does not indicate disease. |
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*Adults: less than 200 units |
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*Children: less than 100 units |
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A titre has significance only if it is greatly elevated (> 200), but a rise in titre demonstrated in paired blood samples taken days apart is more informative for diagnosis. The antibody levels begin to rise after 1 to 3 weeks of strep infection, peaks in 3 to 5 weeks and falls back to insignificant levels in 6 months. |
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Values need to be correlated with a clinical diagnosis. |
Values need to be correlated with a clinical diagnosis.{{cn|date=June 2021}} |
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The aim is to convert it . |
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== Estimation == |
== Estimation == |
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== Mechanism of action == |
== Mechanism of action == |
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{{details|rheumatic fever}} |
{{details|rheumatic fever}} |
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These antibodies produced against the bacteria cross-react with human antigens (mainly [[collagen]]) and hence attack the [[cellular matrix]] of various organs, mainly the heart, joints, skin, brain, etc. |
These antibodies produced against the bacteria cross-react with human antigens (mainly [[collagen]]) and hence attack the [[cellular matrix]] of various organs, mainly the heart, joints, skin, brain, etc.{{cn|date=June 2021}} |
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== Antistreptolysin O titre == |
== Antistreptolysin O titre == |
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Antistreptolysin O titre ('''AS(L)O titer''' or '''AS(L)OT''') is a measure of the blood plasma levels of antistreptolysin O [[antibodies]] used in tests for the diagnosis of a [[Streptococcus|streptococcal infection]] or indicate a past exposure to streptococci.The ASOT helps direct [[antimicrobial]] treatment and is used to assist in the diagnosis of scarlet fever, rheumatic fever, and [[glomerulonephritis|post infectious glomerulonephritis]].{{citation needed|date=July 2020}} |
Antistreptolysin O titre ('''AS(L)O titer''' or '''AS(L)OT''') is a measure of the blood plasma levels of antistreptolysin O [[antibodies]] used in tests for the diagnosis of a [[Streptococcus|streptococcal infection]] or indicate a past exposure to streptococci. The ASOT helps direct [[antimicrobial]] treatment and is used to assist in the diagnosis of scarlet fever, rheumatic fever, and [[glomerulonephritis|post infectious glomerulonephritis]].{{citation needed|date=July 2020}} |
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A positive test usually is >200 units/mL,<ref name=asot_gpnb>Antistreptococcal antibody titres. gpnotebook. URL: [http://www.gpnotebook.co.uk/cache/-1630535637.htm http://www.gpnotebook.co.uk/cache/-1630535637.htm] {{webarchive |url=https://web.archive.org/web/20070126115209/http://www.gpnotebook.co.uk/cache/-1630535637.htm |date=January 26, 2007 }}. Accessed on: March 31, 2007.</ref> but normal ranges vary from laboratory to laboratory and by age.<ref>{{cite journal |vauthors=Danchin M, Carlin J, Devenish W, Nolan T, Carapetis J |title=New normal ranges of antistreptolysin O and antideoxyribonuclease B titres for Australian children |journal=J Paediatr Child Health |volume=41 |issue=11 |pages=583–6 |year=2005 |pmid=16398843 |doi=10.1111/j.1440-1754.2005.00726.x}}</ref> |
A positive test usually is > 200 units/mL,<ref name=asot_gpnb>Antistreptococcal antibody titres. gpnotebook. URL: [http://www.gpnotebook.co.uk/cache/-1630535637.htm http://www.gpnotebook.co.uk/cache/-1630535637.htm] {{webarchive |url=https://web.archive.org/web/20070126115209/http://www.gpnotebook.co.uk/cache/-1630535637.htm |date=January 26, 2007 }}. Accessed on: March 31, 2007.</ref> but normal ranges vary from laboratory to laboratory and by age.<ref>{{cite journal |vauthors=Danchin M, Carlin J, Devenish W, Nolan T, Carapetis J |title=New normal ranges of antistreptolysin O and antideoxyribonuclease B titres for Australian children |journal=J Paediatr Child Health |volume=41 |issue=11 |pages=583–6 |year=2005 |pmid=16398843 |doi=10.1111/j.1440-1754.2005.00726.x|s2cid=9111180 }}</ref> |
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The [[false negative]]s rate is 20 |
The [[false negative]]s rate is 20 to 30%.<ref name=asot_gpnb/> If a false negative is suspected, then an [[anti-DNase B]] titre should be sought. [[False positive]]s can result from [[liver disease]] and [[tuberculosis]].<ref name=asot_gpnb/> |
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==References== |
==References== |
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==External links== |
==External links== |
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*[http://www.gpnotebook.co.uk/simplepage.cfm?ID=-1630535637 Antistreptococcal antibody titres] - GPnotebook.co.uk. |
* [http://www.gpnotebook.co.uk/simplepage.cfm?ID=-1630535637 Antistreptococcal antibody titres] - GPnotebook.co.uk. |
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*[http://www.medterms.com/script/main/art.asp?articlekey=10946 Antistreptolysin O Titer] - medterms.com. |
* [http://www.medterms.com/script/main/art.asp?articlekey=10946 Antistreptolysin O Titer] {{Webarchive|url=https://web.archive.org/web/20130321230429/http://www.medterms.com/script/main/art.asp?articlekey=10946 |date=2013-03-21 }} - medterms.com. |
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*[http://www.ucihs.uci.edu/com/pathology/PathologyServicesManual/..%5CPathology%20Service%20Manual%5CANTISTREPTOLYSIN%20O%20TITER,%20SERUM.htm Antistreptolysin O Titer, Serum] |
* [http://www.ucihs.uci.edu/com/pathology/PathologyServicesManual/..%5CPathology%20Service%20Manual%5CANTISTREPTOLYSIN%20O%20TITER,%20SERUM.htm Antistreptolysin O Titer, Serum] |
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*[https://web.archive.org/web/20060902222743/http://www.healthatoz.com/healthatoz/Atoz/ency/streptococcal_antibody_tests.jsp Streptococcal antibody tests] - healthAtoZ.com |
* [https://web.archive.org/web/20060902222743/http://www.healthatoz.com/healthatoz/Atoz/ency/streptococcal_antibody_tests.jsp Streptococcal antibody tests] - healthAtoZ.com |
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{{Infectious |
{{Infectious blood tests}} |
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[[Category:Antibodies]] |
[[Category:Antibodies]] |
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Latest revision as of 15:16, 24 April 2024
Anti-streptolysin O (ASO or ASLO) is the antibody made against streptolysin O, an immunogenic, oxygen-labile streptococcal hemolytic exotoxin produced by most strains of group A and many strains of groups C and G Streptococcus bacteria. The "O" in the name stands for oxygen-labile; the other related toxin being oxygen-stable streptolysin-S. The main function of streptolysin O is to cause hemolysis (the breaking open of red blood cells)—in particular, beta-hemolysis.
Increased levels of ASO titre in the blood could cause damage to the heart and joints. In most cases, penicillin is used to treat patients with increased levels of ASO titre.
Clinical significance
[edit]When the body is infected with streptococci, it produces antibodies against the various antigens that the streptococci produce. ASO is one such antibody. A raised or rising levels can indicate past or present infection. Historically it was one of the first bacterial markers used for diagnosis and follow up of rheumatic fever or scarlet fever. Its importance in this regard has not diminished.[citation needed]
Since these antibodies are produced as a delayed antibody reaction to the above-mentioned bacteria, there is no normal value. The presence of these antibodies indicates an exposure to these bacteria. However, as many people are exposed to these bacteria and remain asymptomatic, the mere presence of ASO does not indicate disease.
A titre has significance only if it is greatly elevated (> 200), but a rise in titre demonstrated in paired blood samples taken days apart is more informative for diagnosis. The antibody levels begin to rise after 1 to 3 weeks of strep infection, peaks in 3 to 5 weeks and falls back to insignificant levels in 6 months. Values need to be correlated with a clinical diagnosis.[citation needed] The aim is to convert it .
Estimation
[edit]It is done by serological methods like latex agglutination or slide agglutination. ELISA may be performed to detect the exact titre value. To detect the titre value, by a non-ELISA method, one has to perform the above agglutination using a serial dilution technique.[citation needed]
Mechanism of action
[edit]These antibodies produced against the bacteria cross-react with human antigens (mainly collagen) and hence attack the cellular matrix of various organs, mainly the heart, joints, skin, brain, etc.[citation needed]
Antistreptolysin O titre
[edit]Antistreptolysin O titre (AS(L)O titer or AS(L)OT) is a measure of the blood plasma levels of antistreptolysin O antibodies used in tests for the diagnosis of a streptococcal infection or indicate a past exposure to streptococci. The ASOT helps direct antimicrobial treatment and is used to assist in the diagnosis of scarlet fever, rheumatic fever, and post infectious glomerulonephritis.[citation needed]
A positive test usually is > 200 units/mL,[1] but normal ranges vary from laboratory to laboratory and by age.[2]
The false negatives rate is 20 to 30%.[1] If a false negative is suspected, then an anti-DNase B titre should be sought. False positives can result from liver disease and tuberculosis.[1]
References
[edit]- ^ a b c Antistreptococcal antibody titres. gpnotebook. URL: http://www.gpnotebook.co.uk/cache/-1630535637.htm Archived January 26, 2007, at the Wayback Machine. Accessed on: March 31, 2007.
- ^ Danchin M, Carlin J, Devenish W, Nolan T, Carapetis J (2005). "New normal ranges of antistreptolysin O and antideoxyribonuclease B titres for Australian children". J Paediatr Child Health. 41 (11): 583–6. doi:10.1111/j.1440-1754.2005.00726.x. PMID 16398843. S2CID 9111180.
External links
[edit]- Antistreptococcal antibody titres - GPnotebook.co.uk.
- Antistreptolysin O Titer Archived 2013-03-21 at the Wayback Machine - medterms.com.
- Antistreptolysin O Titer, Serum
- Streptococcal antibody tests - healthAtoZ.com