Guest Author - Jim Lowrance

For most hypothyroid patients, their low functioning thyroid state, is caused by an autoimmune disease called “Hashimoto’s Thyroiditis”. The disease is characterized by antibodies that attack the thyroid gland, due to the immune system mistakenly recognizing it as an enemy in the body, that must be destroyed. Usually, the immune system correctly recognizes true invaders and intruders, such as viruses, allergens and bacteria but in the case of autoimmune disease, the immune system sends antibodies to attack a natural part of the body and commonly this will be the thyroid gland (autoimmune thyroid disease).

There is a phenomena that also happens quit commonly in hypothyroid patients with Hashimoto’s and it is referred to by the medical term “Hashitoxicosis”. This is an intermittent condition that takes place as the antibodies cause the thyroid gland to slowly die off. As previously mentioned, these thyroid antibodies, the main ones being the “anti-Thyroglobulin and anti-ThyroidPeroxidase antibodies” (abbreviated TG and TPO), are relentless in attacking and eradicating the enemy they have wrongly identified. During this process, thyroid cells do indeed die off and as they do, the thyroid hormone that is stored in these cells, is released into the bloodstream.

Normally the thyroid releases these stored hormones, into the blood stream, at a rate that is regulated by the pituitary gland, another master gland, that is found in the brain and the pituitary does so, by means of a regulating hormone called ‘TSH”, which stands for “thyroid Stimulating Hormone”. With Hashitoxicosis however, hormone is released at a sporadic rate that is not regulated and as a result, the patient experiencing this, will have spells of mild to severe Hashitoxicosis, despite the fact they are actually hypothyroid.
These spurts of released thyroid, may also be the thyroid gland attempting to fight off the autoimmune attack, in an attempt to delay or prevent its own eventual death from the relentless antibodies attack. These surges of extra hormone actually cause rapid but short-lived spells of hyperthyroidism however, in some patients with highly elevated thyroid antibody levels, these Hashitoxicosis spells may occur more frequently, especially in earlier stages of the disease and may seem like ongoing hyperthyroidism, to the patient.
While it is true that some patients with Hashimoto’s Thyroiditis, may also have co-existing Grave’s Disease (hyperthyroidism), due to also having “TSI” antibodies, standing for “Thyroid Stimulating Immunoglobulins”, which are the antibodies that contribute to Grave’s Disease, the majority of patients have only one disease or the other. When a patient does have Grave’s antibodies co-existing with Hashimoto’s antibodies, it may eventually develop into overt hyperthyroidism however, if it is a patient with only the antibodies causing Hashimoto’s, their intermittent spells of hyperthyroidism, are likely caused by Hashitoxicosis and not by co-existing Grave‘s Disease.

Most patients have less frequent spells of Hashitoxicosis over time, as overt hypothyroidism sets in and much of the thyroid gland’s cells have already died off but when a patient is experiencing this phenomena, it can cause unpleasant and concerning symptoms.

The symptoms of Hashitoxicosis, are those of hyperthyroidism and include the following: excessive energy, feeling keyed-up and nervous, anxiety, tremor, excess sweating, diarrhea, temporary spells of increased heart rate and hypertension.

It is likely better for a patient to reschedule a blood test follow-up, if they are being monitored for thyroid hormone replacement treatment but are going through a spell of Hashitoxicosis, at the time of their blood draw appointment. Some opinions state that the Hashitoxicosis will not affect blood tests results to a significant degree, while others believe it can cause results that show a falsely high reading on lab results, resulting in an incorrect evaluation of hormone levels.

Some medical resources state that Hashitoxicosis is rare however I feel that “mild” cases are likely very common and as a Hashimoto’s patient, I did experience intermittent spells of hyperthyroid symptoms, early into the disease.

Patients experiencing this medical phenomena, should inform their Doctor and this is especially true if the symptoms seem to be severe and ongoing rather than mild and intermittent.