Arsenic intoxication as a cause of megaloblastic anemia

Blood. 1975 Feb;45(2):241-6.


We have described a case of chronic arsenic intoxication associated with pancytopenia and megaloblastic erythropoiesis. The patient had the typical laboratory manifestations of effective erythorpoiesis due to a megaloblastic process, including macroovalocytes, mild pancytopenia, low reticulocyte index, increased marrow cellularity with erythroid hyperplasia, and morphologic evidence of megaloblastic maturation in the marrow. The patient's serum folate and vitamin B12 were normal, and the anemia regressed without therapy. Our case suggests that the combination of megaloblastosis with normoblastic or megaloblastic karyorrhexis,should raise the suspicion of arsenic intoxication in the mind of the observer. In addition, arsenic should be added to the list of agents causing a reversible megaloblastic anemia.

MeSH terms

  • Anemia, Macrocytic / chemically induced*
  • Anemia, Megaloblastic / chemically induced*
  • Arsenic / urine
  • Arsenic Poisoning*
  • Bone Marrow Examination
  • Erythropoiesis
  • Folic Acid / blood
  • Hair / analysis
  • Humans
  • Keratosis / etiology
  • Liver / pathology
  • Male
  • Middle Aged
  • Nails / analysis
  • Neural Conduction
  • Neurologic Manifestations
  • Remission, Spontaneous
  • Reticulocytes
  • Vitamin B 12 / blood


  • Folic Acid
  • Arsenic
  • Vitamin B 12