Macrocytosis / Megaloblastic Anemia
macrocytosis = ...

Macrocytosis / Megaloblastic Anemia

macrocytosis = RBC size > nl, megaloblastic = incr RBC size 2/2 abnl cell division in BM

 • Folate ↓: foliage, 3mo. stores; ↓intake (EtOH use), ↓absorption (celiac, 5-FU, MTX, TMP, phenytoin), ↑ demand (pregnancy, hemolysis, met. cancer); severe form a/w hemolytic anemia & pancytopenia, ↑ homocysteine, MMA nl; Tx: 1-5 mg PO folate QD

 • B12 ↓: beef, 3yr. stores; ↓intake (EtOH use, vegan), pernicious anemia (Ab to IF, gastric parietal cells), ↓ absorption (gastrectomy, celiac, Crohn’s, bacterial overgrowth, tapeworm, chronic pancreatitis); severe form a/w pancytopenia & subacute combined degeneration (dorsal columns, corticospinal tract) w/ dementia, ataxia, paresthesia, ↑ homocysteine, ↑ MMA Tx: 1-2 mg PO B12 QD (as effective as IM if not 2/2 malabsorption). Post-tx, neuro sx start to improve 3mos-1yr

#Macrocytosis #Megaloblastic #Macrocytic #Anemia #diagnosis #management #algorithm #hematology
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