Ethel is a 76 year old widow. She has a history of hypertension (treated with a thiazide diuretic and a calcium channel blocker), hyperlipidemia (treated with an HMGCoA reductase inhibitor), and obesity. Apart from this, she has been relatively healthy, and plays an active role with her 3 grandchildren as well as her church. Unfortunately, over the past few years, she has had increasing difficulty walking because of pain from osteoarthritis in her hips (especially her right hip) and, to a lesser extent, her knees. She therefore undergoes a right total hip arthroplasty. After 6 days in hospital, she is transferred to the rehab ward for further physiotherapy to improve her mobility. Five weeks into her rehab stay she develops a fever of 38.7 C. Additionally her physiotherapist has noticed that over the past 7-8 days Ethel has been less willing to participate in her exercises due to complaints of pain in her right hip. Concerned about Ethel's fever, the nurses give her acetaminophen and call the attending physiatrist to assess the patient for a potential infectious source.