Heme II Unit #2.1

Macrocytic Anemia

large RBC (MCV > 100, MCHC normal, increased MCH)

Megaloblastic

abnormal DNA maturation, delayed nuclear maturation relative to cytoplasm

Nonmegaloblastic

normoblastic maturation

Vitamin B12 or folate deficiency

95% of megaloblastic anemias

B12 Deficiency

most often due to a lack of intrinsic factor

Folate definciency

most often due to inadequate dietary intake

Cobalamin deficiency symptoms

neurologic symptoms that cause numbness, tingling, and weakness of extremities

Thymine (dTTP)

cobalamin and folate are required to make this DNA building block

Peripheral Blood CBC Macrocytic anemia

>100 MCV. MCHC normal. MCH increased. decreased PLT and WBC. retic normal

Blood Smear Macrocytic Anemia

oval macrocytes, HJ bodies, hyperseg neutrophil

ansiocytosis, poik, polychromasia, and megaloblastic erythroblasts

Bone Marrow Macrocytic Anemia

hypercellular, decreased ME ratio, many megaloblasts

Vit B 12 Reference Range

150 - 400

Serum Folate Reference Range

Greater than 4

Homocysteine

increased in both vitamin B12 and folate deficiency

Methylmalonic Acid (MMA)

Increased in vitamin B12 deficiency (B12 needed to metabolize MMA)

Formiminoglutamic acid (FIGLU)

increased in folate deficiency

Folate

green leafy veggies, liver, yeast. Converted to N5-methyl THF transport in blood. One carbon transfer in nucleotide and AA synthesis

Folate Sores

liver with a 3-6mo supply

Folate Deficiency

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