What Causes Swollen Lymph Nodes?

The lymphatic system is the part of the body that circulates lymphatic fluid. The lymph nodes are glands that act as the filtration system for this part of the body. They also store white blood cells, which are an important portion of the immune system that kill invading pathogens. When individuals have a tumor or an infection, the lymph nodes become swollen. When abnormal or diseased cells, bacteria, and viruses pass through the lymphatic system, the lymph nodes stop them from being circulated to other parts of the body. If the body is fighting an illness or infection, the lymph nodes catch debris. There are lymph nodes above the collarbone, on either side of the neck, on either side of the groin, under the jaw, and in the armpits.