What kind of foot infection could cause a swollen groin lymph node?

Swollen lymph nodes: Any type of foot infection that creates inflammation can cause the inguinal lymph nodes (those in the groin) to swell. The lymph nodes filter lymph fluid as it flows through them, trapping bacteria, viruses, and other foreign substances, which are then destroyed by special white blood cells called lymphocytes. See your doctor to treat the foot infection. Warm compresses can help the swelling.