History
The patient is a 65 year-old woman with a past history of mitral valve regurgitation who had a mitral valve repair with Gore-Tex neochordae and mitral valve annuplasty 2 months earlier. She presented to the emergency department with recent-onset dark (Coca-Cola-colored) urine and fatigue. She was found to be newly anemic with an elevated serum LDH and low haptoglobin, and was admitted for further investigation. She denies a past history of hemolysis, anemia or other hematological condition. She has a history of peptic ulcer disease, hypertension and hyperlipidemia. There is no family history of hematological disorders. She is a non-smoker and drinks the occasional glass of wine. She lives with her husband at home, and is a retired librarian. She is taking atorvastatin, lisinopril, metoprolol and warfarin (for the valve). She has no known drug allergies.