Megaloblastic anemia Due to B 12 and folate

Megaloblastic anemia Due to B12 and folate deficiencies. Folic acid deficiency Sources and requirements: Known as folate or petroyl glutamic acid. Water soluble. Present in a variety of foods (green leafy vegetables, fruits and liver and kidney). Heat labile vitamin. Dietary intake for adults 30µg/kg per day.

Structure: Made of three components. Folic acid derived from diet is not biologically active. Once absorbed through the duodenum it hydrolyzed, reduced and methylated to form MTHF. Other form THF (biologically active).

Absorption and metabolism Diet Intestine Poly glutamic acid Poly glutamate Mono glutamate CH3THF Methyl Tetrahydrfolate Glu Folate reductase Reduced and methylated

Circulation Tissue cell CH3THF CH3THF Homocysteine Methionine cTHF THF Glu DNA Synthesis

Causes of folic acid deficiency The main causes is decrease dietary intake: Old age, Alcoholism Chronic diseases. Mal absorption: Tropical sprue. Gluten-sensitive enteropathy. Increase requirements: Pregnancy. Infancy. Malignancy. Drugs: Methotrexate, oral contraceptives.

Laboratory diagnosis of megaloblastic anemia CBC Low hemoglobin level and elevated MCV. PB morphology Macrocytosis, macroovalocytes and hyper segmented neutrophils. Chemical testing Serum folic acid Low (RC FA) BM Hyper cellular BM. Megaloblastic picture (large cells with increased RNA per DNA unit.

Nuclear chromatin appears loose and less mature than nuclear chromatin of normal red cells. Megakaryocytes may be hypersegmented. Giant bands and hypersegmented polymorphonuclear neutrophils are common.

High MCV >98 fl Check smear for macrocytes and hyper segmented neutrophils Serum B12 Serum folate Red cell folate Decreased red cell folate Folic acid deficiency Decreased level of B12 Anti-IF antibodies Yes NO All normal Alcoholism Liver diease ?Hematologic diease Differential Lab Diagnosis of Megaloblastic anemia

Anti-IF antibodies Yes P.A. No Schilling test Abnormal corrected with IF Abnormal Not corrected IF Mal absorption Normal Dietary deficiency