A 23-year-old man comes to the physician for a follow-up examination. Laboratory studies show:
Hemoglobin 16 g/dL
Bleeding time 6 minutes
Prothrombin time 14 seconds
Partial thromboplastin time 45 seconds
Which of the following is the most likely explanation for these findings?
Antibodies against ADAMTS13
Deficiency of von Willebrand factor
Impaired platelet aggregation
Inhibitor of factor VIII
Vitamin K deficiency