Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland. Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidism. Some, however, use the terms interchangeably. Signs and symptoms vary between people and may include irritability, muscle weakness, sleeping problems, a fast heartbeat, heat intolerance, diarrhea, enlargement of the thyroid, hand tremor, and weight loss. Symptoms are typically less severe in the elderly and during pregnancy. An uncommon but life-threatening complication is thyroid storm in which an event such as an infection results in worsening symptoms such as confusion and a high temperature; this often results in death. The opposite is hypothyroidism, when the thyroid gland does not make enough thyroid hormone.
Lambert–Eaton myasthenic syndrome (LEMS) is a rare autoimmune disorder characterized by muscle weakness of the limbs. It is also known as myasthenic syndrome, Eaton–Lambert syndrome, and when related to cancer, carcinomatous myopathy.
Myasthenia gravis (MG) is a long-term neuromuscular junction disease that leads to varying degrees of skeletal muscle weakness. The most commonly affected muscles are those of the eyes, face, and swallowing. It can result in double vision, drooping eyelids, and difficulties in talking and walking. Onset can be sudden. Those affected often have a large thymus or develop a thymoma.
The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or T cells mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. The thymus is located in the upper front part of the chest, in the anterior superior mediastinum, behind the sternum, and in front of the heart. It is made up of two lobes, each consisting of a central medulla and an outer cortex, surrounded by a capsule.
Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss of bladder control. Complications can include urinary tract infections, bladder stones, and chronic kidney problems.
Primary aldosteronism (PA), also known as primary hyperaldosteronism, refers to the excess production of the hormone aldosterone from the adrenal glands, resulting in low renin levels and high blood pressure. This abnormality is caused by hyperplasia or tumors. About 35% of the cases are caused by a single aldosterone-secreting adenoma, a condition known as Conn's syndrome.
A thymoma is a tumor originating from the epithelial cells of the thymus that is considered a rare malignancy. Thymomas are frequently associated with neuromuscular disorders such as myasthenia gravis; thymoma is found in 20% of patients with myasthenia gravis. Once diagnosed, thymomas may be removed surgically. In the rare case of a malignant tumor, chemotherapy may be used.
A thymectomy is an operation to remove the thymus. It usually results in remission of myasthenia gravis with the help of medication including steroids. However, this remission may not be permanent. Thymectomy is indicated when thymoma are present in the thymus. Anecdotal evidence suggests MG patients with no evidence of thymoma may still benefit from thymectomy.
Ocular myasthenia gravis (MG) is a disease of the neuromuscular junction resulting in hallmark variability in muscle weakness and fatigability. MG is an autoimmune disease where anomalous antibodies are produced against the naturally occurring acetylcholine receptors in voluntary muscles. MG may be limited to the muscles of the eye, leading to abrupt onset of weakness/fatigability of the eyelids or eye movement. MG may also involve other muscle groups.
Thyroid disease is a medical condition that affects the function of the thyroid gland. The thyroid gland is located at the front of the neck and produces thyroid hormones that travel through the blood to help regulate many other organs, meaning that it is an endocrine organ. These hormones normally act in the body to regulate energy use, infant development, and childhood development.
Nelson's syndrome is a disorder that occurs in about one in four patients who have had both adrenal glands removed to treat Cushing's disease. In patients with pre-existing adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas, loss of adrenal feedback following bilateral adrenalectomy can trigger the rapid growth of the tumor, leading to visual symptoms and hyperpigmentation. The severity of the disease is dependent upon the effect of ACTH release on the skin, pituitary hormone loss from mass compression, as well as invasion into surrounding structures around the pituitary gland.
Tertiary hyperparathyroidism is a condition involving the overproduction of the hormone, parathyroid hormone, produced by the parathyroid glands. The parathyroid glands are involved in monitoring and regulating blood calcium levels and respond by either producing or ceasing to produce parathyroid hormone.
A mediastinal tumor is a tumor in the mediastinum, the cavity that separates the lungs from the rest of the chest. It contains the heart, esophagus, trachea, thymus, and aorta. The most common mediastinal masses are neurogenic tumors, usually found in the posterior mediastinum, followed by thymoma (15–20%) located in the anterior mediastinum. Lung cancer typically spreads to the lymph nodes in the mediastinum.
Ptosis, also known as blepharoptosis, is a drooping or falling of the upper eyelid. This condition is sometimes called "lazy eye", but that term normally refers to the condition amblyopia. If severe enough and left untreated, the drooping eyelid can cause other conditions, such as amblyopia or astigmatism, so it is especially important to treat the disorder in children before it can interfere with vision development.
Thymic carcinoma, or type C thymoma, is a malignancy of the thymus. It is a rare cancer that is often diagnosed at advanced stages. Recurrence following treatment is common, and thymic carcinoma is associated with a poor prognosis.
Diffuse infiltrative lymphocytosis syndrome (DILS) is a rare multi-system complication of HIV believed to occur secondary to an abnormal persistence of the initial CD8+ T cell expansion that regularly occurs in an HIV infection. This persistent CD8+ T cell expansion occurs in the setting of a low CD4+/CD8+ T cell ratio and ultimately invades and destroys tissues and organs resulting in the various complications of DILS. DILS classically presents with bilateral salivary gland enlargement (parotitis), cervical lymphadenopathy, and sicca symptoms such as xerophthalmia and xerostomia, but it may also involve the lungs, nervous system, kidneys, liver, digestive tract, and muscles. Once suspected, current diagnostic workups include (1) confirming HIV infection, (2) confirming six or greater months of characteristic signs and symptoms, (3) confirming organ infiltration by CD8+ T cells, and (4) exclusion of other autoimmune conditions. Once the diagnosis of DILS is confirmed, management includes highly active antiretroviral therapy (HAART) and as-needed steroids. With proper treatment, the overall prognosis of DILS is favorable.
Kimura's disease is a benign rare chronic inflammatory disorder. Its primary symptoms are subdermal lesions in the head or neck or painless unilateral inflammation of cervical lymph nodes.
Ectopic thymus is a condition where thymus tissue is found in an abnormal location. It usually does not cause symptoms, but may leads to a mass in the neck that may compress the trachea and the esophagus. It is thought to be the result of either a failure of descent or a failure of involution of normal thymus tissue. It may be diagnosed with radiology, such as an ultrasound or magnetic resonance imaging. If it causes illness, surgery can be used to remove it. Recurrence after surgery is very unlikely.
Chronic sclerosing sialadenitis is a chronic (long-lasting) inflammatory condition affecting the salivary gland. Relatively rare in occurrence, this condition is benign, but presents as hard, indurated and enlarged masses that are clinically indistinguishable from salivary gland neoplasms or tumors. It is now regarded as a manifestation of IgG4-related disease.
Neurodegenerative diseases are a heterogeneous group of complex disorders linked by the degeneration of neurons in either the peripheral nervous system or the central nervous system. Their underlying causes are extremely variable and complicated by various genetic and/or environmental factors. These diseases cause progressive deterioration of the neuron resulting in decreased signal transduction and in some cases even neuronal death. Peripheral nervous system diseases may be further categorized by the type of nerve cell affected by the disorder. Effective treatment of these diseases is often prevented by lack of understanding of the underlying molecular and genetic pathology. Epigenetic therapy is being investigated as a method of correcting the expression levels of misregulated genes in neurodegenerative diseases.
