Articles on Medical Diseases and Conditions

Entries Tagged ‘Hypothyroidism’

Summary of Laboratory Tests in Hypothyroidism

From the preceding discussion, several conclusions seem warranted: 1. Serum T4 is the most widely used screening test for hypothyroidism, but some physicians use FT4 or serum TSH assay instead. Values in the upper half of the T4 and FT4 reference range are strong evidence against hypothyroidism unless the TBG level is increased (congenital, pregnancy, […]

Thyroid Tests in Hypothyroidism

Serum thyroxine. Thyroxine is frequently used as the major screening test for hypothyroidism, since the T4 level is low in most cases. There is some overlap between hypothyroid patients and normal persons in the lower part of the T4 reference range, since persons with mild, early, or subclinical disease may be inadvertently included in groups […]

Laboratory Test Patterns in Hypothyroidism

The physiology of thyroid hormone production in hypothyroidism is similar to that described in hyperthyroidism. Hypothyroidism may be divided into three types, depending on functional defect. Each of these categories may have various etiologies: (1) primary (primary thyroid T4/T3 secretion defect), (2) secondary (pituitary TSH secretion defect), and (3) tertiary (hypothalamus TRH secretion defect). From […]

Thyroid Function Tests: Thyrotropin-releasing hormone (TRH) test

Synthetic TRH (Thypinone) is now available. Intravenous bolus administration of TRH normally results in a marked rise in serum TSH levels by 30 minutes after the dose. Serum prolactin levels also increase. There is some disagreement as to how much TRH to administer, with doses reported in the literature ranging from 100-500 µg. Early studies […]

Thyroid Function Tests

The classic picture of hyperthyroidism or hypothyroidism is frequently not complete and may be totally absent. There may be only one noticeable symptom or sign, and even that may be vague or misleading or suggestive of some other disease. The physician must turn to the laboratory to confirm or exclude the diagnosis. There is a […]

Signs and Symptoms of Thyroid Disease

Many persons have at least one sign or symptom that could suggest thyroid disease. Unfortunately, most of these signs and symptoms are not specific for thyroid dysfunction. Enumeration of the classic signs and symptoms of thyroid disease is the best way to emphasize these facts. Hyperthyroidism Thyrotoxicosis from excess secretion of thyroid hormone is usually […]

Anemia Associated With Systemic Disease

As noted in Chapter 3, anemia associated with various chronic diseases is usually normocytic and either normochromic or hypochromic. The serum iron and total iron-binding capacity (TIBC) are typically both decreased. In 100 consecutive patients in our hospital who had chronic disease and red cell or iron-related biochemical abnormalities, 68 had anemia with normal mean […]