Swelling of the thyroid gland (goiter)
If you are affected by Hashimoto's disease, your neck may often look big and thick as shown in the Figure. This is because your thyroid gland is swollen and enlarged. This swelling (goiter) often leads to the diagnosis of Hashimoto's disease.
The size of the goiter varies widely. It may be so small that only an experienced doctor can detect it by touching your neck or it may be so large as to be noticeable to the naked eye. Goiters caused by Hashimoto's disease may be similar to those caused by Graves' disease. In many cases, however, goiters caused by Hashimoto's disease are relatively harder than those caused by Graves' disease, causing the skin of the neck to be lumpy.
Symptoms caused by underactive thyroid functions
Hypothyroidism is a condition characterized by deficient thyroid hormones in the blood.
Of all patients with Hashimoto's disease, about 10% exhibit obvious symptoms of hypothyroidism and about 20% become aware, for the first time, of a shortage of thyroid hormones through blood tests. Therefore, about 30% of all patients are more or less affected by underactive thyroid functions. For the rest of patients (70%), the thyroid gland functions normally.
Many people live without realizing that they have Hashimoto's disease if they have no apparent symptoms except the development of goiter. A large goiter does not necessarily cause the thyroid gland to be severely underactive and a small goiter may result in severe impairment in your thyroid function.
The symptoms of hypothyroidism include:
Swelling is a major symptom of hypothyroidism and is also referred to as "myxedema." Typically, swelling caused by hypothyroidism does not look watery and after you push the affected part of skin with your finger and release the tension you are creating, the skin usually bounces back. You feel stiffness in your hands or face when you wake up in the morning. Severe swelling of the face may cause swollen eyelids, thickened lips and an enlarged tongue. Mucous membranes can also become swollen and if your larynx becomes swollen your voice will become hoarse.
(2) Dry skin
Your skin becomes dry and rough and looks powdery. If you are anemic, you look pale.
(3) Unusual sensitivity to cold
You become sensitive to cold, because the rate of metabolism decreases and the amount of heat produced in your body is reduced. You do not quite feel hot or perspire even in summer.
(4) Weight gain in spite of a poor appetite
You lose your appetite and eat less than usual. However, you gain weight because of swelling and due to a slow metabolism, despite the reduced consumption of calories. Poor gastrointestinal activities cause a feeling of strain in the belly and constipation.
(5) Slow and weak pulse
Your heart works more slowly and gently than usual. When you take your pulse, you have the feeling that the rate is slow and your pulse is weak. The bag containing the heart (pericardium) may be filled with fluid, which causes enlargement of the heart.
(6) Lack of enthusiasm and dullness
You lose interest or enthusiasm for everything. You may become forgetful or inactive or soon fall asleep everywhere. Your speech becomes inarticulate or slow.
(7) Abnormal menstruation or pregnancy
Increased or prolonged bleeding during menstruation may occur. Left untreated, it can often lead to a miscarriage if you get pregnant.
Diseases often confused with Hashimoto's disease
Heart, kidney and liver diseases
If severe hypothyroidism is left unattended for a long time, it can cause swelling in any part of the body or impairment of the heart because of the fluid that collects around it. Therefore, these symptoms may be treated as heart, kidney or liver diseases.
The symptoms caused by hypothyroidism, such as swelling, dry skin, sensitivity to cold, slow movements of the body, slow speech and decline in memory function, can be mistakenly attributed to aging.
"Painless thyroiditis (inflammation of the thyroid gland)," which may develop in patients with Hashimoto's disease, can be mistaken for Graves' disease. In this case, the diagnosis is confirmed by performing tests with radioactive iodine or by examining the thyroid-stimulating substance (TSH receptor antibody) in the blood that is present in patients with Graves' disease.
Left undiagnosed, persons with hypothyroidism may become apathetic or depressed. Patients who display these symptoms may be mistakenly considered to be suffering from mental illnesses or menopausal syndrome.
Hashimoto's disease-related symptoms and disorders to remember
Thyroid hormones are stored in the thyroid gland. Leakage of the hormones from the thyroid gland into the blood leads to a temporary excess of thyroid hormones, which may cause symptoms similar to Graves' disease. No pain is involved and this condition is called "painless thyroiditis." It will disappear spontaneously in 4 months at the latest.
Acute exacerbation of Hashimoto's disease
The severity of thyroid inflammation can increase acutely and cause pain or fever, which is called "acute exacerbation of Hashimoto's disease." Symptoms of hyperthyroidism, such as palpitations and shortness of breath, may develop as thyroid hormones temporarily leak out. This acute exacerbation is treated with painkillers, but the symptoms sometimes return after medication is discontinued. If recurrence persists, surgery may be required.
Other than the absence of enlargement of the thyroid gland, this form of hypothyroidism causes exactly the same symptoms as Hashimoto's disease. The symptoms are often more severe than Hashimoto's disease and are given the same treatment as Hashimoto's disease.
Very rarely, Hashimoto's disease can be a precursor condition of Graves' disease. If you have a relative who has Graves' disease, it is more likely to occur than if you do not. On the other hand, hypothyroidism may develop in patients with Graves' disease after their symptoms are alleviated, making it impossible to differentiate it from Hashimoto's disease.