Although lymphadenopathy often raises concerns of serious illness, it is in most cases a result of relatively benign infections. The human body has approximately six hundred lymph nodes, of which only those in certain regions are palpable in a healthy individual. Lymphadenopathy is a condition which arises when these nodes are found to be abnormal in size, consistency or number.
A diagnosis of lymphadenopathy, in most cases, is based upon a physical examination and medical history of a patient. The condition is classified as “generalized” if the enlargement of lymph nodes is prevalent in two or more noncontiguous areas, or “localized” if only one area is involved.
In the majority of cases where the cause for the condition is benign, it is also easily identifiable. Prevalence of malignancy has been estimated to be as low as 1.1 percent among patients suffering from lymphadenopathy.
The most common cause for lymphadenopathy is infections, particularly viral infections such as the common cold. There is however a range of other underlying causes – including some serious conditions - to lymphadenopathy.
There are a number of infections that can cause lymphadenopathy, from the relatively benign infections such as strep throat or abscessed tooth and ear infections, to the more serious conditions such as sexually transmitted diseases and the HIV virus. Generalized lymphadenopathy is considered to be one of the earliest signs of infection with the HIV virus which is responsible for causing the acquired immunodeficiency syndrome (AIDS). Therefore, it is important for a physician to properly identify cases where lymphadenopathy is secondary to a malignancy or serious condition which needs to be treated on a timely basis. Other infections which cause lymphadenopathy include measles, mononucleosis, wound infections, tuberculosis, toxoplasmosis and cat scratch fever.
Lymphadenopathy can be a result of lymphoma, a cancer that originates in the lymphatic system; or leukemia, a form of cancer that affects the bone marrow and lymphatic system. Along with these two, any other form of cancer that spreads to lymph nodes can also cause lymphadenopathy.
Immune system disorders
Lupus and rheumatoid arthritis are two chronic inflammatory diseases which cause lymphadenopathy. Lupus targets a number of areas of the body including joints, skin, heart and lungs. Rheumatoid arthritis targets the tissue lining found on joints.
In much rarer cases, lymphadenopathy might be caused by certain types of medication. Such medicines include Dilatin, an anti-seizure medication, and the preventative medications used against malaria.