My son had a sonogram on his chest two weeks ago. He had a cyst, fluid build up and swollen lymph nodes. He was on Bactrim 4 tsp 2xdaily and Cephalexin 2 tsp 4Xdaily for two weeks. We went for another sonogram today and the lymph nodes are still swollen. His areola on his left breast is sore and swollen too. Does anyone have a clue as to what I may be facing with him?