Is it normal to go from hypothyroidism to hyperthyroidism

There was no documentation of the degree of exophthalmos. There was diffuse thyromegaly with right lobe more prominent than the left lobe and an audible thyroid bruit. Unfortunately, there was no documented record of the thyroid volume in her retrospectively reviewed clinical notes. Before the onset of the hyperthyroidism symptoms, she had an upper respiratory tract infection, for which she empirically received antibiotics in the community by her GP.

No specific investigations like blood or sputum cultures or X-rays were done. However, according to the patient, following this infection, her diabetes became uncontrolled requiring her to go on insulin, her white cell count dropped and then a few weeks later, her thyroid function tests TFTs started to become deranged. Beginning from that episode of illness in January , her thyroid biochemistry became inconsistent, gradually shifting to a hyperthyroid picture.

A TSH check in August was 0. This is when she also started developing hyperthyroid symptoms. It is difficult to ascertain what exactly caused this conversion, which happened to coincide with the upper respiratory tract infection, and it is difficult to prove a causal association between those two.

However, it is plausible that the infection, probably a viral one, could have switched the conversion from the TSH-blocking antibodies to TSH-stimulating antibodies, making her clinically and biochemically hyperthyroid. Interestingly, her father had underactive thyroid which eventually became overactive. This points to the fact that there may be genetic susceptibility in addition to an environmental trigger causing the conversion from hypothyroidism to hyperthyroidism.

Further research is, however, warranted to prove this. No thyroid-stimulating antibody or thyroid-blocking antibody was checked. Only diagnostic, and not serial, TRAB was performed as per local policy.

A full autoimmune screen was not performed but coeliac screen was negative. Results of thyroid nuclear scan using Technetium 99m. Diffuse homogeneous uptake throughout both lobes of the thyroid with no evidence of toxic nodule or thyroiditis. She is now clinically euthyroid. In this case report, we describe a middle-aged lady who was initially diagnosed with hypothyroidism approximately 30 years ago.

Primary hypothyroidism once diagnosed usually requires lifelong thyroid hormone replacement. Although similar cases have been described in literature, none has been reported after such a long period of almost 30 years. The first similar case was described by Joplin and Fraser in 4 and was followed by several others in the later 60s and 70s 5 , 6 , 7. In Takasu et al. What causes this conversion is not well understood, but there are different theories postulated.

In this case, it happened after an upper respiratory tract infection, and this could implicate an environmental trigger in a genetically susceptible individual as a possible mechanism. One early study 6 , as well as Takasu et al. More recently, Moriarty et al.

Treatment for hypothyroidism and hyperthyroidism differs. While the key to hypothyroidism treatment is to get your thyroid levels up, hyperthyroid treatment focuses on lowering hormone levels. With hypothyroidism, lifelong use of medication is often required.

It helps replace missing thyroxine T4 hormones in the body. Hyperthyroid treatment , on the other hand, may be temporary. Antithyroid medications work by stopping the thyroid gland from making too many hormones. Sometimes beta-blockers are also used to minimize the effects of too much thyroid hormone on the body, such as heart palpitations. More severe cases of hyperthyroidism may require radioiodine treatments. Radioactive iodine destroys thyroid cells to decrease the release of hormones in the body.

This approach is used when medications have failed. For people who want an alternative to radioiodine treatment or antithyroid medications, surgery is an option for hyperthyroidism. Surgery removes the part of the thyroid gland that is causing the underlying issues. Full surgical removal is called a thyroidectomy.

A partial thyroidectomy means only one side of the thyroid gland is removed. The overall outlook and prognosis varies between hypothyroidism and hyperthyroidism. This is not necessarily the case with hyperthyroidism. If antithyroid medications work, then your thyroid hormone levels will normalize without any further issues. Once you have any form of thyroid disease though, your doctor will monitor your condition with occasional blood tests to make sure your thyroid hormones are at optimal levels.

Complications of thyroid disease may include: 7 , 8. The thyroid, a small gland at the base of the front of the neck, produces hormones that help control body temperature, influence the heart rate, regulate the production of protein and maintain the rate at which the body uses fats and carbohydrates.

An underactive thyroid hypothyroidism doesn't produce enough hormone. An overactive thyroid hyperthyroidism produces too much hormone. Symptoms may include unintentional weight gain or loss, persistent fatigue, palpitations, and sensitivity to hot or cold temperatures. But because other health problems cause similar symptoms, diagnosing hypothyroidism or hyperthyroidism based on symptoms alone is not possible. Instead, a blood test that measures your level of thyroid hormone is required.

If a blood test confirms hypo- or hyperthyroidism and verifies that you have switched between them, there could be several possible explanations. If you don't have a history of thyroid problems, the most common reason for a change in thyroid function is inflammation of the thyroid gland thyroiditis.

Initially, thyroiditis leads to overactive thyroid function because when the thyroid first becomes inflamed, it releases all its stored hormones. These cases demonstrate that diagnosis of primary hypothyroidism does not necessarily means lifelong replacement of thyroid hormone.

High index of suspicion should be there for a possible conversion of hypothyroidism to hyperthyroidism if a patient with primary hypothyroidism develops persistent symptoms of hyperthyroidism. Written informed consent was obtained from the patients for publication of this Case report and accompanying image.

A copy of the written consent is available for review by the Editor of this journal. As it is a case series, it did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector. Clin Endocrinol Oxf.

Arch Int Med. J Clin Endocrinol Metab. Article Google Scholar. Clin Endocrinol. Proc Roy Soc Med. Brit Med J. Acta Endocrinol. Google Scholar. James KW: Myxedema preceding hyperthyroidism. J Am Med Assoc. Bhandarkar S, Retnam V: Hyperthyroidism following hypothyroidism. J Postgrad Med. South Med J. PubMed Article Google Scholar. Kaohsiung J Med Sci. Am J Med. Arch Intern Med. Henry Ford Hosp Med J.

Postgrad Med J. Bol Asoc Med P R. Fatourechi V, Gharib H: Hyperthyroidism following hypothyroidism: data on six cases. Am J Med Sci. Br Med J. West J Med. Neuro Endocrinol Lett. Horm Metab Res. J Clin Lab Immunol. Download references.