A 55-year-old African-American man presents to his primary care physician with
shortness of breath and fatigue over the past several months. He complains of diffuse pain in his joints as well as a rash that appeared over his lower extremities. He reports “I’m just not feeling like myself, and I’m starting to wonder if I’m depressed.” His past medical history is notable for obesity,
hypertension, and a 20-pack-year smoking history. He works as a construction contractor. Temperature 37°C (98.6°F),
pulse is 62/min, respirations are 14/min, and
blood pressure is 147/94 mmHg. BMI is 33 kg/m2. Physical examination is notable for submandibular and axillary
lymphadenopathy, as well as red tender lumps on the anterior shins. He subsequently undergoes lymph node biopsy that demonstrates the following pathologic lesion:
Reproduced from: Wikipedia
Which of the following laboratory findings is most commonly associated with this clinical condition?
