What condition is characterized by swelling due to fluid retention in lymph nodes?

Lymphedema is specifically characterized by swelling that occurs due to fluid retention in the lymphatic system, which includes the lymph nodes. This condition arises when there is a blockage or damage to the lymphatic vessels, preventing lymph fluid from properly draining, leading to an accumulation of fluid, primarily in the extremities.

Understanding the distinction of lymphedema is important as it pertains directly to the lymphatic system's functionality, differentiating it from other types of swelling. For instance, while edema can refer to swelling caused by a variety of factors and can occur in multiple tissues throughout the body, lymphedema is confined to fluid retention specifically associated with lymphatic dysfunction. Ascites refers to fluid accumulation in the abdominal cavity, often due to liver disease, while a hydrocele is a fluid-filled sac surrounding a testicle, which is a very different anatomical and physiological issue.