A lymphoproliferative disorder is a medical condition characterized by the dysfunction of the immune system often resulting in excessive production of lymphocytes or white blood cells. The immune system is the body's defense against infections and diseases caused by invading organisms such as bacteria and viruses. People with these disorders often have compromised immune systems, and they are prone to develop severe infections. Malignancy or cancer may also develop as a result.
Lymphocytes are produced in the bone marrow and are usually found in the blood, lymph nodes, and spleen. Lymph nodes are distributed throughout the body to fight against infection. The spleen, located in the left upper section of the abdomen, stores blood and also protects the body against infection. In those with a lymphoproliferative disorder, increased lymphocytes in the bloodstream can lead to the enlargement of the lymph nodes and the spleen.
Many of these disorders originate from inherited conditions and sometimes are caused by acquired immune system dysfunction. Other cases, however, have no known cause. Examples include ataxia telangiectasia, Wiskott-Aldrich syndrome, and autoimmune lymphoproliferative syndrome (ALPS). These conditions are often a result of genetic mutations inherited from one or both parents, and may occur in both men and women.
An X-linked lymphoproliferative syndrome is another inherited disorder that mostly affects men. Many men with this condition have increased susceptibility to develop infections due to the Epstein-Barr virus (EVB). EBV, also known as herpesvirus 4, is often the cause of infectious mononucleosis. Symptoms include lymph node enlargement, fever, and sore throat. These patients may develop lymphoma, a cancer affecting the immune system, and aplastic anemia, a condition marked by failure of the bone marrow to produce new blood cells.
One acquired cause of lymphoproliferative disorder in children includes an infection with the human immunodeficiency virus (HIV). HIV-infected mothers can pass the virus to their children during pregnancy, during delivery, or through breast milk. Disorders can also develop after organ transplant procedures and use of immunosuppressive drugs. Immunosuppressive drugs are administered in order to suppress the immune system from rejecting the new organ.
Diagnostic tools usually used to evaluate patients with lymphoproliferative disorders include a complete blood count (CBC), blood test to detect EBV infection, bone scan, X-ray, and magnetic resonance imaging (MRI). A team of professionals will often manage the patient, and can include oncologists, surgeons, and other medical specialists whose expertise may be needed, depending on the extent of the patient's condition.