单选题
A child with leukemia presents with peteehiae; gums, lips, and nose that bleed easily; and bruising on various parts of her body. Which of the following laboratory test results would the nurse correlate with these findings? A. Platelet count of 80×103/mm3. B. Serum calcium level of 5 mg/dL. C. Fibrinogen level of 75 mg/dL. D. Partial thromboplastin time (PTT) of 38 seconds.
【正确答案】
A
【答案解析】In leukemia, megakaryocytes, from which platelets are derived, are decreased. Normal platelet counts range from 150 to 300×103/mm3. A platelet count of 80×103/ mm3 is low, predisposing the child to bruising and bleeding easily.