Thyroid Disorders

Thyroid disorder is the disease in which the normal release of thyroid hormones is disturbed. Hypothyroidism is a common condition in which the thyroid produces and releases insufficient thyroid hormone into the bloodstream while hyperthyroidism is the condition in which the thyroid gland produce more hormones into the bloodstream.

 


Thyroid Anatomy Review

The thyroid gland is situated in the front of the neck, just below the larynx and adjacent to and surrounding the trachea. The gland has a butterfly shape because it is made up of two lobes connected by a piece of tissue called the isthmus. Each lobe contains follicles that contain hormones that the body requires to function. Two capsules surround the thyroid gland: one on the outside that connects to the voice box muscles and surrounding nerves, and one in the middle that allows the thyroid to move when swallowing or talking.

Thyroid tissue is also made up of two types of cells: follicular cells and parafollicular cells. These two cells are in charge of producing certain hormones that the body requires.

 

Hormones of Thyroid Gland

Thyroid gland secretes three hormones which are the following;

·        Tetraiodothyronine or T4 [throxine]

·        Triiodothyronine or T3

·        Calcitonin

Both T3 and T4 are iodine containing derivatives of amino acid tyrosine

 

Functions of Thyroid Hormones

There are many functions of thyroid hormones, some of which are the following;

Thyroid Hormones can cause lipolysis or lipid synthesis depending on the metabolic state.

Thyroid hormones increase carbohydrate metabolism.

Protein anabolism. In high doses, thyroid hormones can also cause protein catabolism.

Catecholamine permissive effect

 

Thyroid Disorders

There are mainly two types of thyroid disorder. They are Hypothyroidism and Hyperthyroidism

 

 

Hypothyroidism

Hypothyroidism is a common condition in which the thyroid produces and releases insufficient thyroid hormone into the bloodstream. This causes the metabolism to slow.

 

Causes of hypothyroidism

Hypothyroidism can be caused by either a primary or secondary cause. A primary cause is a condition that affects the thyroid directly and causes it to produce low levels of thyroid hormones. A secondary cause is something that causes the pituitary gland to fail, preventing it from sending thyroid stimulating hormone (TSH) to the thyroid and balancing the thyroid hormones.

Primary hypothyroidism causes are far more common. The most common of these primary causes is Hashimoto's disease, an autoimmune condition. This condition, also known as Hashimoto's thyroiditis or chronic lymphocytic thyroiditis, is hereditary (inherited). The thyroid is attacked and damaged by the body's immune system in Hashimoto's disease. This inhibits the thyroid's ability to produce and release enough thyroid hormone.

 

Other common causes of hypothyroidism include:

 

Thyroiditis (inflammation of the thyroid) (inflammation of the thyroid).

Hyperthyroidism treatment (radiation and surgical removal of the thyroid).

Iodine deficiency (a lack of iodine, a mineral used by your thyroid to produce hormones, in your body.

 

 

Sign and Symptoms of Hypothyroidism

Among the most common symptoms of Hyperthyroidism are Fatigue, gaining weight, Increased blood cholesterol level Increased cold sensitivity, Constipation, Skin that is parched, Face puffiness, Hoarseness, Weakness, aches, tenderness, and stiffness of the muscles, Joint discomfort, stiffness, or swelling, Amenorrhea, or irregular menstrual periods, Amenorrhea, or irregular menstrual periods, Hair loss or dry hair.

·        Fatigue

·        gaining weight

·        Increased blood cholesterol level Increased cold sensitivity

·        Constipation

·        Skin that is parched

·        Face puffiness

·        Hoarseness

·        Weakness, aches, tenderness, and stiffness of the muscles

·        Joint discomfort, stiffness, or swelling

·        Amenorrhea, or irregular menstrual periods

·        Amenorrhea, or irregular menstrual periods

·        Hair loss or dry hair

 

 

Hypothyroidism in children may result in:

Growth is slow and poor.

Puberty is delayed.

Inadequate mental development.

 

 

Prevention of hypothyroidism

Screening is regarded as the most effective method of preventing hypothyroidism. Women over the age of 45, in particular, should have their thyroid or thyroid hormone levels checked on a regular basis.

 

 

Complications of hypothyroidism

If hypothyroidism is left untreated for an extended period of time, it may result in A goiter is an enlarged thyroid gland, Obesity, Infertility, Heart conditions such as a slowed heart rate, Depression, Memory impairment, Neuropathy of the periphery.

·        A goiter is an enlarged thyroid gland.

·        Obesity

·        Infertility

·        Heart conditions such as a slowed heart rate

·        Depression

·        Memory impairment

·        Neuropathy of the periphery

 

 

 

Cretinism

Cretinism is a thyroid disorder caused by hypothyroidism. The main cause of cretinism is a lack of iodine in the diet during pregnancy. Hypothyroidism impairs the development of the growing fetus, resulting in mental retardation and stunted growth.

 

Causes of Cretinism

There are two primary causes of cretinism;

Thyroid gland absence and thyroid gland failure to produce thyroid hormone (congenital cretinism or congenital iodine deficiency syndrome).

Dietary iodine deficiency (Endemic cretinism).

                                                                                         

Pathophysiology of Cretinism

An optimal level of maternal thyroid status is required for normal fetal growth. It is the maternal thyroid hormone, which is the only source of fetal brain development that crosses the placenta.

Thyroid hormone is required for fetal and neonatal neuronal cell growth, branching, and myelination. As a result, the absence of thyroid hormone at these stages would have a significant impact on the development of the entire nervous system.

Thyroid hormone is also important for skeletal muscle development as well as soft tissue development. This disproportionate rate of growth causes soft tissue to grow faster than skeletal tissues during cretinism.

 

 

Sign and Symptoms of Cretinism

The Sign and symptoms of cretinism are Stunted growth and mental retardation are common symptoms, petite stature (dwarfism), Mild neurological impairment characterized by decreased muscle tone and coordination, Defects in hearing and speech, Inability to maintain posture and balance with typical walking style, Myxedema, Hyperthyroidism is characterized by an enlargement of the thyroid gland (goiter), The lack of hair and nails, The tone of your voice will be deep and hoarse, Sexual characteristics are retarded, Skin that has thickened.

 

·        Tongue enlargement.

·        Stunted growth and mental retardation are common symptoms.

·        petite stature (dwarfism).

·        Mild neurological impairment characterized by decreased muscle tone and coordination.

·        Defects in hearing and speech.

·        Inability to maintain posture and balance with typical walking style.

·        Myxedema.

·        Hyperthyroidism is characterized by an enlargement of the thyroid gland (goiter).

·        The lack of hair and nails.

·        The tone of your voice will be deep and hoarse.

·        Sexual characteristics are retarded.

·        Skin that has thickened.

·        Tongue enlargement.

 

 

 

Diagnosis of Cretinism

An antenatal screening test in the first month of life can detect congenital cretinism with severe hypothyroidism.

Thyroid scan with technetium (99m pertechnetate).

RAIU (radioactive iodine) test (to differentiate between the congenital absence and a defect in the organification process).

Guthrie's test, for example, is a postnatal blood spot test.

Serum elevation Thyroid binding globulin (TBG) and thyroid stimulating hormone (TSH) levels

Serum T3 levels are elevated, but T4 levels are low.

 

 

Treatment of Cretinism

Once diagnosed, treatment should begin within the first 1-2 weeks of life. Treatment should begin before symptoms appear; if developmental abnormalities and mental retardation appear, they will not be reversed even with thyroid hormone replacement therapy. The dosage is 10 to 15 g per kg of body weight. The dosage should be As one gets older, the dose should be increased.

Treatment with thyroxin should begin as soon as possible because mental retardation that has already occurred is only partially reversible. Physical development and growth can be revived, and mental retardation can be controlled with early treatment.

 

 

Myxedema

Myxedema is a condition caused by advanced hypothyroidism, or thyroxin deficiency; it is the adult form of the disease, which has a congenital form known as cretinism. Myxedema can be caused by a lack of iodine in the diet, atrophy, surgical removal, or a thyroid gland disorder. by radioactive iodine destruction of the gland; or by pituitary gland thyrotrophic deficiency.

 

 

Pathophysiology of Myxedema

Myxedema is a type of cutaneous and dermal edema caused by increased deposition of connective tissue components. An increased amount of protein and mucopolysaccharides separate the connective fibers. Glycosaminoglycan such as hyaluronic acid, chondroitin sulphate, and other mucopolysaccharides are examples of these. [1] This protein-mucopolysaccharide complex binds water, causing non-pitting boggy edema, most notably around the eyes, hands, and feet, as well as in the supraclavicular fossae. Myxedema causes the tongue and laryngeal and pharyngeal mucous membranes to thicken, resulting in thick slurred speech and hoarseness, both of which are common in hypothyroidism.

 

 

Sign and Symptoms of Myxedema

Myxedema symptoms include skin thickening and other hypothyroidism-related symptoms such as fatigue, weight gain, depression, dry skin, and brittle hair. Nonpitting edema is a term used to describe skin thickening or swelling caused by myxedema. In other words, if you press your finger on the affected area's skin and then remove it, you will not see an imprint.

Puffiness in the hands and face, as well as speech slowing, are more serious associated symptoms. Myxedema coma can cause serious or life-threatening symptoms such as slowed breathing, low body temperature, or unresponsiveness.

 

 

Diagnosis of Myxedema

Myxedema coma is typically diagnosed after receiving lab results. If a healthcare provider suspects myxedema, they may begin treatment before receiving lab results to save time and hopefully reverse the body's desire to shut down. When experiencing myxedema symptoms, the following labs are commonly ordered:

Thyroid-stimulating hormone (TSH)

Complete blood count (CBC)

Arterial blood gas (ABG)

Cortisol

 

An electrocardiogram (ECG) may also be performed to check for irregular heart rhythms, which are common with thyroid issues.

 

 

 

 

Treatment of Myxedema

With myxedema, the main focus is on four main treatment options: hormone replacement therapy, steroid therapy, supportive care, and determining what caused the situation in the first place.

·        Hormone replacement therapy

·        Steroid therapy

·        Supportive care

·        and determining what caused the situation in the first place.

 

 

Hormone Replacement

Thyroid hormone therapy is the most important step toward reversing myxedema. This hormone. This hormone therapy will be administered in the form of a synthetic thyroid medication such as Synthroid or levothyroxine.

Within one to two days of starting thyroid hormone therapy, you will notice a significant improvement.

 

Steroid Treatment

Adrenal insufficiency will accompany severe cases of hypothyroidism. Adrenal insufficiency has the potential to be fatal. As a result, treating adrenal insufficiency with steroids is critical until the body regains balance.

 

Helping Hands

Warming and rewarming the body are examples of supportive care. Hypothermia is a serious concern because the body is struggling to maintain a high enough temperature.


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