Assignment task: Nathan is a 58-year-old male patient that has been taking Coumadin on a daily basis for the last 2 years. He has been in a wheelchair for the last 2 years following a work accident. He reports to the physician because he is concerned about an area in his lower right leg that is red and very sore. The physician orders labs with the following results:
PT - 16.3 seconds
D-Dimer = 572 ng/mL
After reviewing these results, the physician admits Nathan to the hospital.
Note: This laboratory uses a PT reagent with an ISI of 1.2; the mean patient PT value is 10.2 seconds
What do you think is the primary reason the physician admitted Nathan to the hospital?