lymphoid tissue The part of the body’s immune system that is important for the immune response and helps protect it from infection and foreign bodies. Lymphoid tissue is present throughout the body and includes the lymph nodes, spleen, tonsils, adenoids, and other structures.
lymphoid Referring to lymphocytes, a type of white blood cell, or to tissue in which lymphocytes develop. Lymphoid tissue is full of lymphocytes, such as a lymph node.
lymphogranuloma venereum An uncommon genital or anorectal (affecting the anus and/or rectum) infection that is caused by a specific type of Chlamydia trachomatis. Abbreviated LGV. Patients with LGV typically have tender lymph nodes in the groin and may recently have had a genital ulcer that resolved on its own. Other patients, in particular those with…
lymphocytosis Having too many lymphocytes. Lymphocytosis may be a marker that infection or disease is present.
lymphocytopenia Having an abnormally low number of lymphocytes. There are many causes of lymphocytopenia, ranging from medication toxicity to a variety of diseases.
lymphocytic Referring to lymphocytes, a type of white blood cell. For example, lymphocytic inflammation in the skin is skin that is infiltrated with lymphocytes.
lymphocyte A small white blood cell that plays a large role in defending the body against disease. Lymphocytes are integrally involved in many immune responses. There are two main types of lymphocytes: B cells and T cells. Lymphocytes are often present at sites of chronic inflammation.
lymphedema A condition in which excess fluid collects in tissue and causes swelling. Lymphedema may occur in the arm or leg after lymph vessels or lymph nodes in the underarm or groin are removed. It usually causes painless swelling.
lymphatic system The tissues and organs, including the bone marrow, spleen, thymus, and lymph nodes, that produce and store cells that fight infection and disease. The channels that carry lymph are also part of this system.
lymphatic Pertaining to a small, thin channel that is similar to a blood vessel and that collects and carries tissue fluid (lymph) from the body. This fluid ultimately drains back into the bloodstream.
lymphangioma An abnormal structure that consists of a collection of blood vessels and lymph vessels that are overgrown and clumped together. Depending on its nature, a lymphangioma may grow slowly or quickly. Lymphangiomas can cause problems because of their location. For example, a lymphangioma around the larynx might cause a breathing problem.
lymphangiogram An X-ray of the lymphatic system for which a dye is injected to outline the lymphatic vessels and organs.