What is the difference between an inguinal hernia and a swollen lymph node in the groin?

Difference: A inguinal hernia is a tear of the muscle/fascia in the inguinal canal with protrusion of the colon through the tear. A lymph node is a structure which is always in the area. Thus a hernia introduces a structure which is not supposed to be there and a lymph node is a regular resident of the area. Hope this helps.

Monitoring Centers: Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells and digested food. Lymph nodes "taste" the lymph for anything bad like bacteria/viruses/cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react. They shrink when all is well.