Canine Lymphadenopathy Study Guide

Overview and Clinical Importance

Lymphadenopathy refers to the enlargement or pathological change of lymph nodes and is one of the most common clinical findings in canine practice. While the term lymphadenomegaly is technically more accurate for describing lymph node enlargement, lymphadenopathy is used synonymously in clinical practice. This finding can indicate a wide spectrum of underlying conditions, ranging from benign reactive processes to life-threatening malignancies such as lymphoma. The ability to accurately assess, diagnose, and manage lymphadenopathy is essential for NAVLE success and clinical practice.

Lymphadenopathy may involve peripheral (palpable) lymph nodes, internal visceral lymph nodes, or both. It can be localized (affecting a single node or regional group), regional (affecting nodes in a specific anatomic area), or generalized (affecting multiple lymph node regions throughout the body). Understanding the pattern of lymph node involvement is critical for developing an appropriate differential diagnosis list.

Anatomy of Canine Peripheral Lymph Nodes

The lymphatic system is essential for immune surveillance and fluid homeostasis. Lymph nodes filter lymphatic fluid and serve as sites for antigen presentation and immune cell activation. Understanding peripheral lymph node anatomy is critical for systematic physical examination and accurate sample collection.