Proteinaceous Lymphadenopathy Definition Enlarged lymph node with partial or total replacement of normal architecture by deposits of acellular amorphous material with the characteristic features of amyloid or of other proteinaceous…
Lymph Node Infarction Definition Massive necrosis of coagulative type involving most of the nodal parenchyma and sparing only a narrow subcapsular rim. Pathogenesis Because of their abundant vascularity and well-developed…
Vascular Transformation of Sinuses Definition Benign vascular proliferation of lymph nodes with characteristic sinus distribution. Pathogenesis Vascular transformation of sinuses (VTS) is a rare condition in which the vasoproliferative process…
Introduction A variety of substances of endogenous and exogenous origin, when carried to the regional lymph nodes, trigger cellular reactions. The histiocytes, cells endowed with phagocytic ability, are the main…
Drug-induced Lymphadenopathy Definition Lymphadenopathy that can mimic malignant lymphoma associated with drug therapy, usually as a result of a hypersensitivity reaction. A wide variety of drugs can induce lymphadenopathy (Table…
Castleman Lymphadenopathy Definition In the original reports by Castleman et al. (1,2), Castleman disease (CD) was described as a large, benign, asymptomatic mass involving mediastinal lymph nodes. Fifty years later,…
Introduction A variety of vascular disorders may affect the lymph nodes, resulting in ischemic infarction, benign vascular prolife-rations, or malignant vascular neoplasms. Lymph nodes are well vascularized, and therefore ischemic…
Drug-Induced Lymphadenopathy: Methotrexate Definition Lymphoproliferative disorders associated with methotrexate therapy, usually administered to patients with connective tissue diseases. Introduction Patients with immunodeficiency have an increased risk of lymphoproliferative disorders, in…
Tumor-Reactive Lymphadenopathy Definition Reactive, usually enlarged, regional lymph nodes draining tumor areas. Pathogenesis Regional lymph nodes tributary to tumor-bearing organs are considered anatomic barriers to tumor spread. They are also…
Introduction Lymphadenopathies may occur in patients treated with a variety of immunomodulatory drugs. Drugs such as prednisone, azathioprine, methotrexate, cyclosporine, and others are used to diminish the symptoms of hyperimmune…
