Indirect Causality
<h3>Examples of how exogenous pathogens may indirectly cause somatic diseases via autoimmune mechanism provoked by infection:</h3>
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<h3>Grave's Disease</h3>
<p>Diffuse toxic goiter or Graves-von Basedown disease of the thyroid may be caused by anti-TSH receptor autoimmune attack provoked by <em>Yersinia enterocolitia</em> (or some other germs) in HLA D3-D4 positive individuals.</p>
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<h3>Parvovirus B19 (B19V) infection</h3>
<p>In certain individuals it can trigger autoimmune processes against erythroid stem cells in bone marrow, causing aplastic anemia. This only affects a small part of the population who carry HLA haplotypes of HLAB2, HLAB3 and HLAB8. In the rest of the population it causes a light infectious disease such as roseola or doesn't cause disease at all.</p>
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<p>Similar situations occur with E. coli and non-specific ulcerative colitis...</p>
<p>Between chlamydia and pneumonia...</p>
<p>Between cytomegalovirus and atherosclerosis</p>
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<p>Between enterovirus and many non-infectious diseases, beginning with sugar diabetes and ending with myocardial infarction.</p>
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<p>It isn't the germ that directly caused the disease but the indirect triggering of the immune system against self-antigens of particular individuals.</p>
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<p>“Everything is infectious until proven otherwise.” – Noel Rose & Yehuda Shoenfeld, <em>Infection and Autoimmunity</em>, 2008 (but everything is also auto-immune until proven otherwise). Interactions between our microbiota may trigger the immune system and if it has certain genetic peculiarities it may attack the self organism.</p>
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<p>Another example is Diabetes Mellitus Type 1, "a dream of the epidemiologist and nightmare of the geneticist" - G.S. Eisenbarth </p>
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<p>This can be provoked by many infectious agents but only in carriers of HLAD3/D4 alleles. Contact with the provoking agent can long precede appearance of sugar diabetes.</p>
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<p>Any of these factors may trigger autoimmune processes against beta cells in predisposed persons:</p>
<ul>
<li>Enterovirus Coxsackie B4 & ECHO</li>
<li>Rubeola (German measles)</li>
<li>Parotitis (mumps) virus</li>
<li>Some chemical agents such as bovine serum albumin from cow’s milk, nitrosamines, several drugs like Pentamidine.</li>
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