A 30-year-old woman with a history of systemic lupus erythematosus presents with bruising, fatigue, and mild confusion. Her laboratory findings include a hemoglobin level of 9.0 g/dL, platelet count of 25,000/µL, elevated LDH, and schistocytes on a peripheral smear. ADAMTS13 activity is <10%. What is the best way to monitor her response to treatment?
