A 43-year-old female presents to your office with complaints of increasing fatigue, body aches, and shortness of breath with exertion for the past 2 months. She notes she has several bruises on her arms and legs, which cannot be explained from an injury. She is currently taking no prescribed medications, no medical history and denies use of over the counter medications or herbal supplements.

Upon examination, you note a moderately ill appearing, pale, patient with petechiae on her lower extremities. She is awake, alert, but slow to respond to your questions. Her vital signs are within normal limits. Her head-to-toe examination is otherwise normal.

CBC results

WBC- 52,000 cells/μL
RBC- 1.15 million cells/ μl
RDW- 20.4%
Hgb- 5.2 g/dl
Hct- 14.8%
Platelets- 120,000 cells/ μL
What further testing would you consider ordering?