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==Pathophysiology==
==Pathophysiology==


In both TSS (caused by S. aureus) and TSLS (caused by S. pyogenes), disease progression stems from a [[superantigen]] toxin that allows the non-specific binding of MHC II with [[T cell]] receptors, resulting in polyclonal T-cell activation.
In both TSS (caused by S. aureus) and TSLS (caused by S. pyogenes), disease progression stems from a superantigen toxin that allows the non-specific binding of MHC II with T cell receptors, resulting in polyclonal T-cell activation. TSS due to Clostridium sordelli has also been identified in women undergoing medical abortion.


Usually exotoxin producing strains of Staphylococcus aureus, a bacterium. S. aureus commonly colonizes skin and mucous membranes in humans. TSS has been associated with use of tampons and intravaginal contraceptive devices in women and occurs as a complication of skin abscesses or surgery.
===TSST-1 associated Toxic shock syndrome===
 
This infection can occur via the [[skin]] (e.g. cuts, surgery, burns), [[vagina]] (via [[tampon]]), or [[pharynx]].  However, most of the large number of individuals who are exposed to or colonized with toxin-producing strains of ''[[Staphylococcus aureus|S. aureus]]'' or ''[[Streptococcus pyogenes|S. pyogenes]]'' do not develop toxic shock syndrome.  One reason is that a large fraction of the population has protective antibodies against the toxins that cause TSS.<ref>{{cite journal |author=McCormick J, Yarwood J, Schlievert P |title=Toxic shock syndrome and bacterial superantigens: an update |journal=Annu Rev Microbiol |volume=55 |issue= |pages=77-104 |year= |pmid=11544350}}</ref>  It is not clear why the antibodies are present in people who have never had the disease.
 
Toxin production by ''S. aureus'' requires a protein-rich environment, which is provided by the flow of menstrual blood, a neutral vaginal pH, which occurs during menstruation, and elevated oxygen levels, which is provided by the tampon that is inserted into the normally anaerobic vaginal environment.<ref>{{cite journal |author=McCormick J, Yarwood J, Schlievert P |title=Toxic shock syndrome and bacterial superantigens: an update |journal=Annu Rev Microbiol |volume=55 |issue= |pages=77-104 |year= |pmid=11544350}}</ref>  Although ulcerations have been reported in women using super absorbent tampons, the link to menstrual TSS, if any, is unclear.  The toxin implicated in menstrual TSS is capable of entering the bloodstream by crossing the vaginal wall in the absence of ulcerations.<ref>{{cite journal |author=Schlievert P, Jablonski L, Roggiani M, Sadler I, Callantine S, Mitchell D, Ohlendorf D, Bohach G |title=Pyrogenic toxin superantigen site specificity in toxic shock syndrome and food poisoning in animals |journal=Infect Immun |volume=68 |issue=6 |pages=3630-4 |year=2000 |pmid=10816521}}</ref>  Women may avoid problems by choosing a tampon with the minimum absorbency needed to control menstrual flow and using tampons only during active menstruation. Alternately, a woman may choose to use a different kind of menstrual product that may eliminate or reduce the risk of TSS, such as [[sanitary napkins]] or a [[menstrual cup]].


TSST-1 associated Toxic Shock Syndrome. A protein based exotoxin, called toxic shock syndrome toxin-1 (TSST-1), which acts as a superantigen (SAg) has been identified that is associated with strains of S. aureus isolated from patients with TSS. SAgs bind to certain regions of major histocompatibility complex (MHC) class II molecules of antigen-presenting cells (APCs) outside the traditional antigen-binding site and at the same time bind in their native form to T cells at specific motifs of the variable region of the beta chain (Vbeta) of the T cell receptor (TcR). This interaction triggers the activation (proliferation) of the targeted T lymphocytes and leads to release of high amounts of various cytokines and other effectors by immune cells. <ref name="pmid12635926">{{cite journal |vauthors=Alouf JE, Müller-Alouf H |title=Staphylococcal and streptococcal superantigens: molecular, biological and clinical aspects |journal=Int. J. Med. Microbiol. |volume=292 |issue=7-8 |pages=429–40 |year=2003 |pmid=12635926 |doi=10.1078/1438-4221-00232 |url=}}</ref>The SAg binds through its dodecapeptide region to human epithelial cells, possible CD40 or another unknown receptor, stimulating the production of pro-inflammatory chemokines. Small amounts of cytolysins, particularly α-toxin, are required to facilitate this process through combinations of their cytotoxic and pro-inflammatory properties. The SAg must penetrate the mucosal barrier to cause disease, but it appears likely that submucosal SAg activities, rather than systemic activities, are sufficient for TSS production. <ref name="pmid24838262">{{cite journal |vauthors=Stach CS, Herrera A, Schlievert PM |title=Staphylococcal superantigens interact with multiple host receptors to cause serious diseases |journal=Immunol. Res. |volume=59 |issue=1-3 |pages=177–81 |year=2014 |pmid=24838262 |pmc=4125451 |doi=10.1007/s12026-014-8539-7 |url=}}</ref>. SAgs cause release of IL-1 beta and IL-6 from antigen presenting cells (APC) and have a direct action on the hypothalamic temperature control center. Staphylococcal toxic shock syndrome toxin 1 (TSST-1) is also the cause of menstrual toxic shock syndrome (mTSS) associated with vaginal colonization by Staphylococcus aureus; IL-8 and MIP-3α, may originate from vaginal epithelial cells, which are highly chemotactic.<ref name="pmid20335433">{{cite journal |vauthors=Schlievert PM, Nemeth KA, Davis CC, Peterson ML, Jones BE |title=Staphylococcus aureus exotoxins are present in vivo in tampons |journal=Clin. Vaccine Immunol. |volume=17 |issue=5 |pages=722–7 |year=2010 |pmid=20335433 |pmc=2863369 |doi=10.1128/CVI.00483-09 |url=}}</ref>
==References==
==References==
{{reflist|2}}
{{reflist|2}}

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Pathophysiology

In both TSS (caused by S. aureus) and TSLS (caused by S. pyogenes), disease progression stems from a superantigen toxin that allows the non-specific binding of MHC II with T cell receptors, resulting in polyclonal T-cell activation. TSS due to Clostridium sordelli has also been identified in women undergoing medical abortion.

TSST-1 associated Toxic shock syndrome

TSST-1 associated Toxic Shock Syndrome. A protein based exotoxin, called toxic shock syndrome toxin-1 (TSST-1), which acts as a superantigen (SAg) has been identified that is associated with strains of S. aureus isolated from patients with TSS. SAgs bind to certain regions of major histocompatibility complex (MHC) class II molecules of antigen-presenting cells (APCs) outside the traditional antigen-binding site and at the same time bind in their native form to T cells at specific motifs of the variable region of the beta chain (Vbeta) of the T cell receptor (TcR). This interaction triggers the activation (proliferation) of the targeted T lymphocytes and leads to release of high amounts of various cytokines and other effectors by immune cells. [1]The SAg binds through its dodecapeptide region to human epithelial cells, possible CD40 or another unknown receptor, stimulating the production of pro-inflammatory chemokines. Small amounts of cytolysins, particularly α-toxin, are required to facilitate this process through combinations of their cytotoxic and pro-inflammatory properties. The SAg must penetrate the mucosal barrier to cause disease, but it appears likely that submucosal SAg activities, rather than systemic activities, are sufficient for TSS production. [2]. SAgs cause release of IL-1 beta and IL-6 from antigen presenting cells (APC) and have a direct action on the hypothalamic temperature control center. Staphylococcal toxic shock syndrome toxin 1 (TSST-1) is also the cause of menstrual toxic shock syndrome (mTSS) associated with vaginal colonization by Staphylococcus aureus; IL-8 and MIP-3α, may originate from vaginal epithelial cells, which are highly chemotactic.[3]

References

  1. Alouf JE, Müller-Alouf H (2003). "Staphylococcal and streptococcal superantigens: molecular, biological and clinical aspects". Int. J. Med. Microbiol. 292 (7–8): 429–40. doi:10.1078/1438-4221-00232. PMID 12635926.
  2. Stach CS, Herrera A, Schlievert PM (2014). "Staphylococcal superantigens interact with multiple host receptors to cause serious diseases". Immunol. Res. 59 (1–3): 177–81. doi:10.1007/s12026-014-8539-7. PMC 4125451. PMID 24838262.
  3. Schlievert PM, Nemeth KA, Davis CC, Peterson ML, Jones BE (2010). "Staphylococcus aureus exotoxins are present in vivo in tampons". Clin. Vaccine Immunol. 17 (5): 722–7. doi:10.1128/CVI.00483-09. PMC 2863369. PMID 20335433.


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