Viruses and thyroiditis: an update
Actually, while I’m still here, Mary Shomon has just posted a link to a virology paper on thyroiditis. I’m very interested in this topic, because I think this is what happened to me.
Viral infections are frequently cited as a major environmental factor involved in subacute thyroiditis and autoimmune thyroid diseases [...]
First defined by De Quervain, subacute thyroiditis is a self-limited inflammatory disorder of the thyroid gland. The disease is most prevalent in females, usually characterized by a sudden onset of neck pain and thyrotoxicosis. Clinically the disease has several characteristics typical of viral infections including a typical viral prodrome with myalgias, malaise and fatigue. [...]
The first descriptions showed a tendency for the disease to follow upper respiratory tract infections or sore throats, which explained why a viral infection has most often been implicated as the cause. Clusters of the disease have been reported during outbreaks of viral infection. Onset of the disease are observed between June and September and this seasonal distribution is almost identical to that of established infections due to some enteroviruses (Echovirus, Coxsackievirus A and B), suggesting that enterovirus infections might be responsible for a large proportion of cases.
An association between subacute thyroiditis and HLA B35 is noted in all ethnic groups tested  and two-thirds of patients manifest HLA-B35. Familial occurrence of subacute thyroiditis  and recurrence during the course of time  are associated with HLA B35. Thus, the onset of subacute thyroiditis is genetically influenced and it appears that subacute thyroiditis might occur through a susceptibility to viral infection in genetically predisposed individuals. [...]
Virus-like particles were first demonstrated in the follicular epithelium of a patient suffering from subacute thyroiditis. Judging from the size, it was thought to be influenza or mumps virus , which was concordant with an increased frequency of antibodies to the influenza B virus in patients with thyrotoxicosis [...]
Some cases could be due to the mumps virus. Subacute thyroiditis has occurred in epidemic form: patients with subacute thyroiditis diagnosed during a mumps epidemic were found to have circulating anti-mumps antibodies even without clinical evidence of mumps [...]
Enteroviruses have been suspected. Patients with subacute thyroiditis, who had no clinical evidence of viral disease, demonstrated increases by at least four times in viral antibodies. These viral antibodies included antibodies to mumps virus, but also coxsackie, adenovirus and influenzae. Coxsackie viral antibodies were the most commonly found, and the changes in their titers most closely approximated the course of the disease [...]
I won’t quote the whole paper. Theory A is that I’m one of those HLA B35 people, and that I was hit like this:
1. Influenza at age 13 (diagnosed “fibromyalgia”)
2. Withdrawal from the Pill at age 26
3. Major stress of DVT and use of warfarin at age 26 (adrenal?)
2. Adenovirus in France at age 28 (laughed at by doctor when I requested hormone tests)
3. Yersinia at age 32 (a bacterial infection associated with autoimmune thyroiditis)
I *hope* to hell that I had an adenovirus in France, and not cocksackievirus, because cocksackie can damage the heart, pancreas and liver. Though it would explain a lot.
Theory B is that I am autoimmune, but it hasn’t been detected – which would also explain a few things. To make matters as confusing as they should be, the paper goes on to say, “Unknown autoantibodies are found in patients with subacute thyroiditis, and a higher prevalence of thyroid autoantibodies after a mean follow-up interval of 4 years but at low titers has been observed.”
In other words, non-autoimmune thyroiditis may also be autoimmune thyroiditis on a subtle level. We may be talking about a grey scale of autoimmunity here.
Another point of interest is that the HLA B35 genotype seems particularly susceptible to AIDs. Some scientists have even theorised that a percentage of Europeans have an inherent resistance to AIDs because they inherited a polymorphism from ancestors who survived the Black Death. I guess I’m pretty lucky not to be born in Medieval times, because I would have been buboed up to my armpits and dropped like a fly.