A 9-year-old boy is brought to the physician for a follow-up examination after the removal of a tooth. During the procedure, he had prolonged bleeding that did not resolve with pressure and gauze packing and eventually required suture placement. Physical examination shows a soft and nontender abdomen. The spleen is not palpable. Laboratory results are as follows: This patient most likely has a deficiency involving which of the following factors?

Question

A 9-year-old boy is brought to the physician for a follow-up examination after the removal of a tooth. During the procedure, he had prolonged bleeding that did not resolve with pressure and gauze packing and eventually required suture placement. Physical examination shows a soft and nontender abdomen.  The spleen is not palpable.  Laboratory results are as follows:  This patient most likely has a deficiency involving which of the following factors?

Quizplus · Accepted Answer

Eductional Objective: A normal bleeding time indicates adequate platelet hemostatic function.  A normal activated partial thromboplastin time (aPTT) indicates an intact intrinsic coagulation system.  Prolonged prothrombin time in the setting of normal aPTT indicates a defect in the extrinsic coagulation system at a step that is not shared with the intrinsic system.

A 9-Year-Old Boy Is Brought to the Physician for a Follow-Up