A 65-year-old man presents to your clinic with headaches, dizziness, and blurred vision for the past month. He also notes pruritus after hot showers. He has a 50 pack/year history of smoking and denies using alcohol or drugs. There is no other significant medical history and he takes no medications. Vital signs include HR 86, RR 16, oxygen saturation 98% on room air, and BP 128/85 mm Hg.
Physical examination is remarkable for ruddiness of the face. Spleen is enlarged and palpable well below the left costal margin. Cardiovascular and pulmonary examination results are normal.
Laboratory values are as follows: hemoglobin 20 g/dL, hematocrit 58%, WBC count 13,000 with a normal differential, and platelet count 480,000/µL.
Which of the following tests should be performed next in the evaluation of this patient?
A. Erythropoietin level
B. Coagulation studies
C. Bone marrow biopsy
D. Leukocyte alkaline phosphatase
E. Iron studies
Physical examination is remarkable for ruddiness of the face. Spleen is enlarged and palpable well below the left costal margin. Cardiovascular and pulmonary examination results are normal.
Laboratory values are as follows: hemoglobin 20 g/dL, hematocrit 58%, WBC count 13,000 with a normal differential, and platelet count 480,000/µL.
Which of the following tests should be performed next in the evaluation of this patient?
A. Erythropoietin level
B. Coagulation studies
C. Bone marrow biopsy
D. Leukocyte alkaline phosphatase
E. Iron studies