ABSTRACT
Lymph node aspiration is extremely safe, rapid, easy to perform, and is recommended for all enlarged lymph nodes. The specific lymph node that is draining an area where a primary lesion is located should be sampled to evaluate the patient for spread of disease. Sampling multiple lymph nodes should be performed when a systemic disease is suspected, as cytologic features may vary among different nodes. Culture via standard microbiology techniques is rarely performed using lymph node aspirates and is generally limited to selected bacterial diseases. The lymph node parenchyma is surrounded by a connective tissue capsule extending inwards in fibrous septae. Lymphadenitis is characterized by a conspicuous number of inflammatory cells, although the lymphoid population is generally prevalent, and may be associated with some degree of lymphoid hyperplasia. Classification of lymphomas has been widely revised during the last 50 years both in human and in veterinary medicine.
