Which of the following is found in megaloblastic macrocytosis but not in nonmegaloblastic macrocytosis?
A)Decreased WBC count and vitamin B₁₂ levels
B)Decreased hemoglobin and hematocrit
C)Normal-to-decreased reticulocyte count
D)Increased serum bilirubin

Question

Quizplus · Accepted Answer

Megaloblastic macrocytosis is typically caused by a deficiency in vitamin B₁₂ or folate. Therefore, decreased vitamin B₁₂ levels would only be found in megaloblastic macrocytosis, not nonmegaloblastic macrocytosis. Additionally, a decreased WBC count can be seen in megaloblastic macrocytosis due to the impairment of DNA synthesis. Hemoglobin and hematocrit can be decreased in both megaloblastic and nonmegaloblastic macrocytosis. Normal-to-decreased reticulocyte count can also be seen in both types of macrocytosis. Increased serum bilirubin is not typically associated with either type of macrocytosis.

Which of the Following Is Found in Megaloblastic Macrocytosis but Not