Types Of Thyroid Disorders: Types, Symptoms And Treatment Of Thyroid Disorders

The thyroid gland, a butterfly-shaped organ located in the neck and measuring approximately 2 inches, plays a crucial role in the endocrine system. Its primary hormones, triiodothyronine (T3) and thyroxine (T4) regulate the basal metabolic rate, heart rate, body weight, intelligence quotient, and even reproductive health. Any changes and disturbances in these hormone levels lead to thyroid disorders.

This article explores the complex system of thyroid diseases, their causes, symptoms, and available treatment options. 

Types of Thyroid Disorders

The different types of thyroid diseases are discussed in brief below:

1.Hypothyroidism

Hypothyroidism develops when the thyroid gland fails to produce adequate hormones, leading to a reduced metabolism. Common symptoms include fatigue, weight gain, sensitivity to cold, dry skin, constipation, and depression. Autoimmune disorders such as Hashimoto’s thyroiditis or iodine deficiency are common causes of hypothyroidism.

2.Hyperthyroidism

This a medical condition in which the thyroid gland secretes excessive amounts of hormones, leading to an elevated basal metabolic rate. Common symptoms include rapid heartbeat, weight loss, hyperthermia, hyperactivity, anxiety, excessive sweating, and, in some cases, muscle atrophy. The most common cause of this condition is Graves’ disease, an autoimmune disorder.

3.Thyroid Nodules

Thyroid nodules are abnormal growths or lumps within the thyroid gland, which can be solid or cystic. Approximately 95% of these nodules are not cancerous. However, they can cause complications by applying pressure to the neck area or altering hormone levels. While most nodules are benign, some may overproduce thyroid hormones and cause hyperthyroidism.

4.Thyroid Cancer

A cancer arising from the thyroid gland is a rare disease and is often curable. It is classified into four main types: papillary (the most common and slow-growing), follicular, medullary, and anaplastic (which grows rapidly and is the most aggressive form). Some signs include a visible neck lump, voice changes, difficulty swallowing, and enlarged glands (lymph nodes).

Hypothyroidism: The Underactive Thyroid

The sections below cover the causes, risk factors, symptoms and complications of hypothyroidism.

Causes of Hypothyroidism

The causes of this disease are as follows:

Hashimoto's Disease: This autoimmune disorder occurs when the immune system mistakenly targets the thyroid gland, slowly reducing its ability to produce hormones.

• Drugs (Lithium, Amiodarone)
• Birth-related disorder of the thyroid gland
• Iodine deficiency
• Pituitary gland disorders
• Acute thyroiditis (which follows a viral infection or occurs during pregnancy)

Key Risk Factors for Hypothyroidism

Though hypothyroidism can affect individuals of any gender, it is more prevalent in women due to hormonal changes during menstruation, pregnancy, and menopause. Other risk factors include autoimmune diseases, genetic predisposition, pregnancy-related hormonal shifts, and a history of thyroid surgery.

Symptoms of Hypothyroidism

The signs of hypothyroidism develop gradually over years, affecting multiple systems in the body, including:

• Fatigue and decreased sex drive
• Weight gain
• Dry skin and frizzy hair
• Muscle soreness
• High blood cholesterol
• Depression and anxiety
• Short attention span
• Irregular menstrual periods

Complications Associated with Hypothyroidism

If one takes proper treatment, there are no significant complications associated with hypothyroidism. However, if left untreated, hypothyroidism can lead to the following potential complications:

• Goiter
• Cardiovascular diseases
• Infertility
• High risk of miscarriage
• Peripheral neuropathy

Hyperthyroidism: The Overactive Thyroid

Know about the causes, risk factors, symptoms and complications of hyperthyroidism.

Causes of Hyperthyroidism

Here are the causes of hyperthyroidism:

• Graves' Disease: An autoimmune disorder where the immune system attacks the thyroid, causing it to overproduce hormones.
• Overactive Thyroid Nodules: Benign lumps producing hormones independently.
• Thyroiditis: Inflammation, including postpartum or painless types, causing temporary symptoms.
• Excessive Iodine: Overconsumption of iodine overstimulates thyroid hormones.
• Pituitary Tumors: Rare benign tumors disrupting hormone regulation.

Key Risk Factors for Hyperthyroidism

Hyperthyroidism symptoms are more likely to appear in women and those aged 60 or older. The risk is higher in individuals with:

• Pernicious anemia
• Type 1 and Type 2 diabetes
• Primary adrenal insufficiency
• Autoimmune disorders such as Graves’ disease
• High dietary consumption of iodine

Symptoms of Hyperthyroidism

• Though the symptoms of hyperthyroidism may vary across individuals, some common symptoms include:
• Unexpected weight loss despite increased appetite
• Faster metabolic rate
• Muscle weakness and reduced endurance
• Rapid or irregular heartbeat
• Increased nervous system activity
• Hand tremors
• Mood swings or irritability

Complications of Untreated Hyperthyroidism

The complications of untreated hyperthyroidism are:

• Cardiovascular Complications: Long-term hyperthyroidism can cause abnormal heart rhythms, increasing the risk of clots, stroke, heart failure, and heart muscle damage.
• Graves' Ophthalmopathy: Causes eye inflammation, bulging, irritation, vision problems, and increased sensitivity to light.
• Bone and Muscle Degradation: Increases bone turnover, reducing bone density and raising osteoporosis risk.
• Reproductive and Hormonal Disruptions: Affects menstrual cycles, fertility, and hormonal balance.

Thyroid Nodules

Thyroid nodules are discrete masses or lumps within the thyroid gland that differ from normal tissue architecture. Also called ‘breast nodules,’ they can be solitary or multiple, simple or complex, and may or may not signify a clinical diagnosis.

Types of Thyroid Nodules

Here are the different forms of thyroid nodules:

• Solid Nodules: Well-defined, dense nodules with no cystic spaces, requiring careful examination.
• Cystic Nodules: Benign, fluid-filled nodules from degenerative changes in thyroid tissue.
• Colloid Nodules: Commonly benign nodules filled with colloid fluid have a low cancer risk.
• Follicular Adenoma: Benign tumours from thyroid follicular cells requiring examination to rule out malignancy.
• Multinodular Goiter: Several nodules in the throat, often linked to iodine deficiency, causing thyroid imbalances.

Diagnosis and Evaluation

Take a look at the methods for diagnosis and evaluation of thyroid nodules:

• Clinical Assessment: Evaluation of medical history, neck palpation, and symptoms like swallowing difficulty and voice changes.
• Laboratory Investigations: Tests for TSH, T4, T3, and FNAC (Fine Needle Aspiration Cytology) to assess thyroid function and classify nodules.
• Imaging Techniques: Thyroid ultrasound to assess nodule size, shape, texture, margins, and vascularity.

Thyroid Cancer: A Comprehensive Overview

Here are the four common types of thyroid cancer:

1. Papillary Thyroid Cancer: The most common type, making up 75-80% of cases, is slow-growing and may spread to lymph nodes. However, it is highly treatable.
2. Follicular Thyroid Cancer: This type accounts for about 15% of cases, can spread to bones and organs, and may complicate treatment.
3. Medullary Thyroid Cancer: It is a rare type, making up 2% of cases, where genetic factors play a role, and some patients inherit the risk.
4. Anaplastic Thyroid Cancer: The most aggressive type, making up 2% of cases, is fast-growing and spreads quickly to other parts of the body.

Symptoms and Early Detection

Most thyroid carcinomas are occult initially, making timely diagnosis difficult.  However, some noticeable symptoms include:

• Large and apparent neck mass or nodule
• Sore throat and difficulty in swallowing 
• Voice changes, remarkably increased hoarseness
• Constriction around the neck region
• Inflammation in lymph nodes

Diagnostic Tests for Thyroid Diseases

The different tests for diagnosing thyroid diseases are given below.

• Blood Tests: TSH, T3, T4, Thyroid antibody tests
• Imaging Tests: Ultrasound, Thyroid scan, CT scan
• Biopsy Techniques: Fine Needle Aspiration Cytology (FNAC)

Treatment Options for Thyroid Disorders

Thyroid management plans are personalised to correct hormone imbalances and address related conditions through medication, hormone therapy, and sometimes surgery. Levothyroxine treats hypothyroidism, while antithyroid medications control excess hormone production. Radioactive iodine targets thyroid tissue, and beta-blockers manage hyperthyroid symptoms.

Surgical interventions for thyroid disorders, such as thyroidectomy, involve removing part or all of the thyroid gland. A total thyroidectomy requires lifelong levothyroxine to maintain metabolism, while a partial thyroidectomy's need for hormone replacement depends on the amount of thyroid tissue removed.

Lifestyle and Dietary Considerations

The health of the thyroid gland is closely linked to diet, with nutrients like iodine, selenium, and zinc supporting proper function.

Foods like fish, Brazil nuts, and lean meat are beneficial while limiting raw cruciferous vegetables and moderating goitrogenic foods can help control hormones and metabolism. Lifestyle changes, including exercise, stress-reducing meditation, and a proper sleep-wake routine, are crucial for managing thyroid disease.

Conclusion 

The most common thyroid disorders include hypothyroidism, hyperthyroidism, thyroid nodules, and thyroid cancers, among others. Preventive healthcare by conducting thorough check-ups, healthy diets, exercise, stress management, and behaviour changes helps those diagnosed with these disorders manage and improve their well-being.