title: Causes of macrocytic anemia among 628 patients: mean corpuscular volumes of 114 and 130 fL as critical markers for categorization.
abstract: There have been no studies on the distribution of causes of macrocytic anemia with respect to mean corpuscular volume (MCV) cutoff values. We retrospectively investigated the causes of macrocytic anemia (MCV ≥100 fL) among 628 patients who visited the outpatient hematology clinic in Tohoku University Hospital. To ensure data validity, we also analyzed data from 307 patients in eight other hospitals in the Tohoku district. The leading causes of macrocytic anemia (number of patients, %) were myelodysplastic syndromes (121, 19.3 %), suspected bone marrow failure syndromes (BMF; 74, 11.8 %), aplastic anemia (51, 8.1 %), plasma cell dyscrasia (45, 7.2 %), and vitamin B12 deficiency (40, 6.4 %) in Tohoku University Hospital. We made three primary findings as follows. First, the most common cause of macrocytic anemia is BMF. Second, lymphoid and solid malignancies are also common causes of macrocytosis. Third, macrocytic anemia may be classified into three groups: Group 1 (megaloblastic anemia and medications), which can exceed MCV 130 fL; Group 2 (alcoholism/liver disease, BMF, myeloid malignancy, and hemolytic anemia), which can exceed MCV 114 fL; and Group 3 (lymphoid malignancy, chronic renal failure, hypothyroidism, and solid tumors), which does not exceed MCV 114 fL. These conclusions were supported by the results from eight other hospitals.
authors.affiliation: Department of Hematology and Rheumatology, Tohoku University Graduate School of Medicine, 1-1, Seiryo-cho, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Natsuko
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: Department of Hematology and Rheumatology, Tohoku University Graduate School of Medicine, 1-1, Seiryo-cho, Aoba-ku, Sendai, 980-8574, Japan. j-kame@med.tohoku.ac.jp.
authors.forename: Junichi
authors.initials: J
authors.lastname: Kameoka
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: Department of Gastroenterology and Hematology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Tamai
authors.affiliation: Department of Hematology/Oncology, Internal Medicine, Iwate Medical University, Morioka, Japan.|Department of Hematology, Iwate Prefectural Central Hospital, Morioka, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Murai
authors.affiliation: Department of Hematology, Yamagata Prefectural Central Hospital, Yamagata, Japan.
authors.forename: Riko
authors.initials: R
authors.lastname: Honma
authors.affiliation: Department of Cardiology and Hematology, Fukushima Medical University, Fukushima, Japan.
authors.forename: Hideyoshi
authors.initials: H
authors.lastname: Noji
authors.affiliation: Department of Hematology, Sendai Medical Center, Sendai, Japan.
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Yokoyama
authors.affiliation: Department of Hematology, Miyagi Cancer Center, Natori, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Tomiya
authors.affiliation: Department of Neurology, Hematology, Metabolism, Endocrinology, and Diabetology, Faculty of Medicine, Yamagata University, Yamagata, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Neurology, Hematology, Metabolism, Endocrinology, and Diabetology, Faculty of Medicine, Yamagata University, Yamagata, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Ishizawa
authors.affiliation: Department of Hematology/Oncology, Internal Medicine, Iwate Medical University, Morioka, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Ito
authors.affiliation: Department of Hematology/Oncology, Internal Medicine, Iwate Medical University, Morioka, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Ishida
authors.affiliation: Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sawada
authors.affiliation: Department of Hematology and Rheumatology, Tohoku University Graduate School of Medicine, 1-1, Seiryo-cho, Aoba-ku, Sendai, 980-8574, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Harigae
mesh_terms: D000741:Anemia, Aplastic; D000748:Anemia, Macrocytic / Q000097:blood / Q000145:classification / Q000209:etiology* / Q000473:pathology; D000749:Anemia, Megaloblastic; D001855:Bone Marrow Diseases; D000080983:Bone Marrow Failure Disorders; D004909:Erythrocyte Indices; D006457:Hemoglobinuria, Paroxysmal; D006801:Humans; D009369:Neoplasms / Q000150:complications; D012189:Retrospective Studies
keywords: Bone marrow failure syndromes; MCV; Macrocytic anemia; Megaloblastic anemia; Solid tumors