This is for my husband who has been in hospital for a week now with no real answers. Here's a brief history. 48 yr old male, first full knee replacement August 2003, then the low-grade staph infections started. Has been treated with vancomycin on 3 separate occasions. Each infection resulted in a total debridement and sometimes full replacement. He had a Strep infection in the knee in September 2008 with 2 debridements and 12 weeks of IV Ceftriaxone. All clear. 6 weeks ago, developed cellulitis. Treated with Keflex. All clear. Blood work done one week ago came back clean. That night he developed a fever, headache and pain so bad in his leg from his hip to his ankle that he couldn't move. Next morning admitted to hospital and placed on IV Ceftiaxone as well as two other antibiotics. Nothing has gotten rid of the headache although it is subsiding. They drained 300cc of yellow pus-like fluid from the knee yesterday. We are at a loss as to why this keeps happening. Any help or directions would be greatly appreciated. He is in real jeopardy of losing the leg all together.