Hypothyroidism

NURSING ADULTS II

HYPOTHYROIDISM

NAME

SCHOOL

TABLE OF CONTENTS

INTRODUCTION 3

ANATOMY AND PATHOPHYSIOLOGY 3

SIGNS AND SYMPTOMS 7

RISK FACTORS 8

DIAGNOSTIC MEASURES 9

TREATMENT 10

RECENT DEVELOPMENTS 11

COMPLICATIONS 12

BIBLIOGRAPHIES 17

Introduction

This document aims to provide you with a comprehensive overview of a thyroid disease called Hypothyroidism. Section one will discuss the anatomy and pathophysiology of the disease to show its common causes and what specific parts of the body are affected. The next section will detail how hypothyroidism is detected and the possible complications that may arise if it is left untreated. Treatment procedures will be highlighted in succeeding section including preparations, possible complications or side effects and medications that are usually given to patients with this type of disease. After which, literature on some of the most recent developments involving treatment, devices, research into causative factors and the like will be presented. The psychosocial aspects of the disease will also be discussed briefly and some recommendations on where else to locate new information about the disease process will be indicated. It should be noted that this document is by no means a prescriptive form of information. It does not intend to replace professional opinion nor serve as a substitute. If you experience any of the symptoms of hypothyroidism, it is still best to seek help from your doctor or health center.

Anatomy and Pathophysiology

As mentioned, Hypothyroidism is a disease of the thyroid, a gland which regulates the body's metabolism, heart rate, blood pressure, and body temperature, among other functions. It is a butterfly-shaped gland located at the base of your neck, just below your Adam's apple (please see Annex A for an image of the thyroid gland). Although it weighs less than an ounce, the thyroid gland has an enormous effect on your health (Mayo clinic, 2004). In fact, a variety of disorders can plague it, including autoimmune disorders, benign and malignant tumors, and goiter (an enlargement of the thyroid that may be caused by either over- or under-production of thyroid hormone) (Brown, V. Disrupting a delicate balance: environmental effects on the thyroid, 2003).

In order to produce your thyroid's two principal products--thyroxine (T4) and triiodothyronine (T-3), together known as the "thyroid hormone", the body utilizes an element called Iodine. This hormone maintains the rate at which your body uses fats and carbohydrates, burn calories, help regulate your body temperature, influence your heart rate and help in controlling the production of protein. Your thyroid gland also produces calcitonin, a hormone that regulates the amount of calcium in your blood.

The rate at which thyroxine and triiodothyronine are released is controlled by your pituitary gland and your hypothalamus -- an area at the base of your brain that acts as a thermostat for your whole system. First, the hypothalamus signals the pituitary gland to produce a hormone called thyroid-stimulating hormone (TSH). TSH signals the thyroid gland itself to capture iodine from the blood to synthesize, store, and release T-4. Once T-4 has reached an adequate circulating level, the hypothalamus and pituitary reduce their output of Thyroid Releasing Hormone (TRH) and TSH until the T-4 level again drops. [T.sub.4] circulates in the blood both freely and bound to carrier proteins. When T-4 finally reaches the cells, it is converted to T-3 which is actually the biologically active form. T-3 can alsoe released by the thyroid and can stick to carrier proteins.

Sometimes, the thyroid fails to produce enough hormones. The Mayo Clinic (2004) provides a comprehensive list of possible causes for this condition:

Autoimmune disease (Hashimoto's thyroiditis). Autoimmune disorders occur when your immune system produces antibodies that attack your own tissues. Sometimes this process occurs within the thyroid gland. Scientists aren't sure why the body produces antibodies against itself. Some think a virus or bacteria might trigger the response, while others believe a genetic flaw may be involved. Most likely, autoimmune diseases result from more than one factor. But however it happens, these antibodies affect the thyroid's ability to produce hormones.

Treatment with radioactive iodine. The most common treatment for people who produce too much thyroid hormone (hyperthyroidism) is radioactive iodine. The radioactive material becomes concentrated in the thyroid gland, reducing its function. Often, however, function is reduced too much, resulting in hypothyroidism. Anti-thyroid drugs such as methimazole (Tapazole) -- also used to treat conditions in which the thyroid produces too much thyroid hormone -- may cause hypothyroidism as well.

Radiation therapy. Radiation used to treat cancers of the head and neck can affect your thyroid gland and may lead to hypothyroidism.

Thyroid surgery. Removing all or a large portion of your thyroid can diminish or halt hormone production. In that case, you'll need to take thyroid hormones for life.

Medications. A number of medications can contribute to hypothyroidism. One of the most common is lithium, which is used to treat certain psychiatric disorders. If you're taking medication, ask your doctor about its effect on your thyroid gland.

Less often, hypothyroidism may result from one of the following:

Congenital disease. Approximately one in 3,000 babies in the United States is born with a defective thyroid gland or no thyroid gland at all. In most cases, the thyroid gland didn't develop normally for unknown reasons, but some children have an inherited form of the disorder. Often, infants with congenital hypothyroidism appear normal at birth. That's one reason why doctors now recommend that all newborns receive thyroid tests when they're between 24 and 72 hours old.

Pituitary disorder. About 1 percent of cases of hypothyroidism are caused by the failure of the pituitary gland to produce enough TSH -- usually due to