Patient Presentation
A 55-year-old Caucasian male presented to the emergency department with a 2-day history of what looked like dried crusts of blood on his forearms. They were mildly painful and tender, but non-pruritic. His medical history was significant for atrial fibrillation, treated with sotalol and direct current cardioversion 2 weeks prior. At that time, enoxaparin was started to bridge anticoagulation to warfarin. Concurrent medications included aspirin.
Physical examination revealed scattered, discrete and coalescent, 3-mm to 5-mm, tense, superficial hemorrhagic vesicles on an erythematous base located on the bilateral forearms (see image above). Abdominal skin examination revealed large ecchymoses located at injection sites. Laboratory results showed normal platelets, hemoglobin and hematocrit values. The international normalized ratio and partial thromboplastin time were slightly increased (1.27 (normal 0.9 to 1.1 seconds) and 36.8 seconds (normal 23.0 to 34.0 seconds), respectively). Biopsy was obtained and evaluated for definitive diagnosis.