title: Vitamin B12 deficiency and early rise in mean corpuscular volume.
abstract: An increase in the mean corpuscular volume (MCV), while not diagnostic of vitamin B12 or folate deficiency, is a valuable, readily available screening test. I discuss six instances where an increased MCV was recorded months prior to diagnosis and could, if noted, have led to an earlier diagnosis.
mesh_terms: D000368:Aged; D000752:Anemia, Pernicious / Q000097:blood / Q000175:diagnosis; D003937:Diagnosis, Differential; D004909:Erythrocyte Indices; D005494:Folic Acid Deficiency / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D014805:Vitamin B 12 / Q000097:blood; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000175:diagnosis*
chemical_list: D014805:Vitamin B 12