Thyroid diseases: Hypothyroidism, hyperthyroidism, goiter and nodules

Thyroid hormones, keys to the proper functioning of the body


Thyroid disease – The function of the thyroid gland is to produce and store thyroid hormones in quantity necessary to respond to the body’s demand.  These hormones are thyroxine or T4 and triiodothyronine or T3. Both contain iodine and are released into the blood, through which they reach the different tissues of the body, where they perform very important and varied functions.

Thyroid hormones are necessary for the body to use energy, maintain body temperature, and for the brain, heart, muscles, and other organs to function normally.

 Alterations in thyroid function are diagnosed by an analytical determination of TSH and thyroid hormones (T4 and T3).

Thyroid disease
Thyroid diseases

Most common thyroid diseases

  • Gland function deficit ( hypothyroidism )
  • Excess function of the same ( hyperthyroidism )
  • Thyroid nodular disease and its enlargement ( goiter )


In hypothyroidism, there is a reduction in the production of thyroid hormones.


In the case of hypothyroidism, the symptoms are highly variable and nonspecific, such as fatigue, poor tolerance to cold, a tendency to swelling and weight gain, constipation, and dry skin.

It is always essential to carry out an analytical diagnosis and a second confirmatory analysis is usually recommended, before establishing a definitive diagnosis.


Treatment is based on replacing the deficit in thyroid function and for this, synthetic thyroid hormone or levothyroxine is used.  Administration will generally be daily and is most efficiently absorbed on an empty stomach.

To verify that the levothyroxine dose is adequate, analytical controls will be carried out, always allowing a minimum of 4-6 weeks after the start of treatment or change of dose. Once the correct dose is verified, as the analyzes normalize, the controls can be spaced out, becoming semi-annual or even yearly.

Untreated hypothyroidism problems

Untreated hypothyroidism can contribute to increased cholesterol levels.  During pregnancy, it can cause complications such as premature delivery, high blood pressure, miscarriages, slowing the growth and development of the baby. Over time, it can cause obesity, joint pain, infertility, or heart disease.


In hyperthyroidism there is an increased production of thyroid hormones.


In hyperthyroidism, the most common symptoms are nervousness, anxiety, irritability, tiredness, rapid heartbeat, palpitations, weight loss, shaking hands, insomnia, heat intolerance, excessive sweating, and increased number of bowel movements.


Treatment is aimed at slowing down the excess function of the thyroid gland.  Antithyroid drugs (methimazole, carbimazole, and propylthiouracil) are used to reduce the production of thyroid hormones by the thyroid.

Another treatment option is radioiodine, which is generally used when medical treatment fails or when severe complications appear secondary to antithyroid treatment. 

Finally, there is the surgical option that is indicated in the presence of large goiters, with local compressive symptoms, suspicion of malignancy, presence of large nodules, short-term gestational desire, and severe ocular involvement.

To verify that the antithyroid dose is adequate, periodic analytical controls will be carried out, always allowing a minimum of 4-6 weeks to elapse, until the thyroid function is normalized.

Untreated hyperthyroidism problems

Hyperthyroidism should always be treated, since without treatment a high mortality (even 20%) has been described. If left untreated, it can cause heart problems, such as arrhythmias, thromboembolic complications in cases of atrial fibrillation, as well as worsening of coronary artery disease or heart failure. At the bone level, the risk of osteoporosis increases .

Thyroid nodules


Many cases of nodular thyroid disease are asymptomatic or cause slight cosmetic discomfort. When there are symptoms, they are usually caused by compression of the structures near the thyroid and usually manifest as persistent hoarseness, difficulty breathing, difficulty swallowing, etc.


The cause of its development is unknown.  It is sometimes related to iodine deficiency, since this nutrient is necessary to produce thyroid hormones. Another risk factor is the presence of thyroid nodules in various members of the family.

Diagnostic tests

Diagnosis can be made by physical examination, but the most accurate technique is thyroid ultrasound -a painless and innocuous test that does not involve radiation-, which allows localization of non-perceptible lesions during physical examination and indicates the benignity or malignancy of the thyroid nodule.


However, there are no effective treatments to prevent them from growing.  Surgery will be indicated if the size is large, there is suspicion of malignancy or there is compressive symptoms.


Goiter is an enlargement of the thyroid.


Like nodular thyroid disease, it does not usually produce symptoms and the usual ones are due to compression of the structures near the thyroid, causing persistent hoarseness, difficulty in breathing or swallowing, etc.


Iodine deficiency can also be associated with the development of goiter, that is, an enlargement of the thyroid gland.

Dr. Ashwani Kumar is highly skilled and experienced in treating major and minor general medicine diseases.