Thyroid gland dysfunction/disease

Hypothyroidism and hyperthyroidism are the two primary pathological conditions that involve the thyroid glands. Laboratory testing of thyroid hormones is used to diagnose and document the presence of thyroid disease, a condition that often presents with vague and subtle symptoms. Accurate measurement of thyroid hormone concentrations is key to the proper diagnosis of thyroid gland dysfunction. 

Laboratory tests most commonly used to evaluate patients for thyroid gland dysfunction are listed in Table 52-1. Familiarity with normal physiology and with pathophysiology is important if these tests are to be properly used and selected. However, it is important to note that normal serum thyroid hormone concentrations do not exclude thyroid disease, and abnormal thyroid tests do not always indicate thyroid disease. Diffuse or nodular thyroid enlargement, for example, maybe seen in euthyroid patients. ... 

Addisons disease, results from progressive destruction or dysfunction of the adrenal glands by a local disease process or systemic disorder (Box 51-12), Worldwide, infectious diseases are the most common cause of primary adrenal insufficiency and include tuberculosis, fongal infections (histoplasmosis and cryptococcosis), and cytomegalovirus infections. Autoimmune adrenalitis accounts for more than 70% of cases reported in the Western world, with adrenal autoantibodies noted in more than 75% of cases,. The adrenal glands are atrophic, with loss of cortical cells but an intact medulla. Almost 50% of patients with autoimmune adrenalitis have an associated autoimmune disease with autoimmune thyroid disease the most common. 

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