Search results
Results from the WOW.Com Content Network
While the pathogenesis of cervical thymus cyst is still unclear, there are two main mechanisms by which this lesion occurs: Congenital: During the fetal development, the thymus forms from the third branchial pouch which descends lateral to the mediastinum toward the thyroid gland. A remnant of this thymic tissue can persist during its descent ...
Nezelof syndrome is an autosomal recessive [6] congenital immunodeficiency condition due to underdevelopment of the thymus.The defect is a type of purine nucleoside phosphorylase deficiency with inactive phosphorylase, this results in an accumulation of deoxy-GTP which inhibits ribonucleotide reductase.
Thymic hypoplasia is a condition where the thymus is underdeveloped or involuted. Causes
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.
The two most common genetic syndromes linked to thymus development defects are 22q11.2 deletion syndrome and CHARGE syndrome. Patients with these syndromes exhibit a variety of symptoms because the genes TBX1 and CHD7, associated with these disorders, play a role in the development of the entire midline region. [1]
Thymic hyperplasia can be divided into three groups namely, those without any pre-existing medical condition, those recovering from a pre-existing medical condition such as pneumonia, corticosteroid therapy, radiation therapy, chemotherapy, surgery, and burns, and those with other disorders such as hyperthyroidism, juvenile myasthenia gravis, [5] sarcoidosis, pure red cell aplasia.
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 .
Abnormalities of the thymus can result in a decreased number of T cells and autoimmune diseases such as autoimmune polyendocrine syndrome type 1 and myasthenia gravis. These are often associated with cancer of the tissue of the thymus, called thymoma, or tissues arising from immature lymphocytes such as T cells, called lymphoma.