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 Table of Contents  
Year : 2018  |  Volume : 2  |  Issue : 3  |  Page : 114-115

Vitamin B12 deficiency presenting as hemolytic anemia

Department of Medicine, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar

Date of Web Publication4-Oct-2018

Correspondence Address:
Dr. Muhammad Aamir Waheed
Department of Medicine, Hamad General Hospital, PO Box 3050, Doha
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/LJMS.LJMS_31_18

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Vitamin B12 deficiency is not an uncommon condition. Commonly patient presents with megaloblastic anemia and pancytopenia. There are reports in the literature of Vitamin B12 deficiency associated with other immunological conditions. We report such a case of Vitamin B12 deficiency associated with hemolytic anemia in a 36-year-old Indian man, who presented with pancytopenia and hemolytic anemia. Workup for other causes of hemolytic anemia was negative, and the patient responded to treatment with Vitamin B12, with resolution of pancytopenia and hemolysis. Clinicians need to be aware of this association as both conditions occur rarely together and unawareness may lead to unnecessary investigation and procedures.

Keywords: Hemolytic anemia, Megaloblastic anemia, Vitamin B12

How to cite this article:
Waheed MA, Elzouki A. Vitamin B12 deficiency presenting as hemolytic anemia. Libyan J Med Sci 2018;2:114-5

How to cite this URL:
Waheed MA, Elzouki A. Vitamin B12 deficiency presenting as hemolytic anemia. Libyan J Med Sci [serial online] 2018 [cited 2023 Mar 28];2:114-5. Available from: https://www.ljmsonline.com/text.asp?2018/2/3/114/242729

  Introduction Top

Vitamin B12 deficiency is a relatively common condition. The etiology is usually nutritional, pernicious anemia, and drug induced. The usual presentation is that of megaloblastic anemia or pancytopenia. Other presentations are rare. We describe a case of Vitamin B12 deficiency presenting with megaloblastic anemia and hemolytic anemia at the same time. Although this presentation has been described in the literature as a rare occurrence, it has not been reported from “Middle East” before.

  Case Report Top

A 36-year-old Indian gentleman was brought to the emergency of “Hamad General Hospital, Qatar,” with the chief complaint of “fatigue anorexia “and” tachypnea.” “On examination,” he was looking pale and jaundiced, “but” there was no organomegaly. On investigations, he was found to have anemia with a hemoglobin of 4 “g/dl.” The anemia was macrocytic. Other blood counts were also low “and” he was diagnosed to have pancytopenia. Reticulocyte counts were not elevated, but the peripheral smear was suggestive of a picture of hemolytic anemia; subsequently, coomb test was found to be negative. Further workup showed that haptoglobin was very low that is <4 and Vitamin B12 was also found to be very low that is <100 ng/L. Flow cytometry was negative for paroxysmal nocturnal hemoglobinuria and other autoimmune workup was all negative except antiparietal cell antibodies and anti-intrinsic factor antibodies. There was no G6PD deficiency, and ultrasound abdomen did not show any abnormalities. The patient was started on injection Vitamin B12, and within a few days, his blood counts started to improve and the pancytopenia resolved. The patient was subsequently discharged home with intramuscular Vitamin B12 according to protocol of Vitamin B12 replacement. On subsequent follow-up in the medical outpatient, he was found to be stable with hemoglobin of 11 “g/dl” and normal platelets and white cell counts. His bilirubin which was previously found to be high has normalized, and he was generally feeling well.

  Discussion Top

Vitamin B12 functions as a cofactor or coenzyme that participates in various biochemical reactions, including DNA synthesis,[1] which promotes normal maturation of blood cells. It also contributes to the myelination of central nervous system as well as maintenance of its function. Deficiency of Vitamin B12 can lead to megaloblastic anemia and neuropathy. Intramedullary destruction or hemolysis of fragile and abnormal red blood cell precursors is the results of ineffective erythropoiesis secondary to defective DNA and cell maturation. The picture may resemble macroangiopathic hemolytic anemia.[2] If such condition persisted, it may deplete iron storage and lead to concomitant iron deficiency anemia.[3] Few cases of hemolytic anemia and Vitamin B12 deficiency occurring together have been described in the literature.[4],[5] The patient presentation with pancytopenia and high mean corpuscular volume and being vegetarian is suggestive of Vitamin B12 deficiency. Unusual presentation is the increased lactate dehydrogenase low haptoglobin and high bilirubin which was subsequently found to be due to hemolysis. Further workup for the etiology of Vitamin B12 deficiency shows that the cause is due to pernicious anemia as both the intrinsic factor and anti-parietal cell antibodies were positive. Coomb test is negative, though there are instances of immune hemolytic anemia with negative coomb test, a case of combined hemolytic anemia and megaloblastic anemia has been reported in Croatia.[6] Cases of combined autoimmune hemolytic anemia and Vitamin B12 deficiency with negative coomb test have also been reported.[7] The negative coomb test may be due to low level of IgG at the time of performing the assay or it may subsequently become positive in future. The association of Vitamin B12 deficiency due to pernicious anemia and associated immune thrombocytopenia has been reported multiple times in the literature. There are few instances in which autoimmune hemolytic anemia with coomb test positive has also been reported in the literature,[8],[9],[10],[11],[12],[13] such patient usually responded to treatment with steroids along with Vitamin B12 replacement. Interestingly, Vitamin B12 therapy may result in negative coomb test on further testing. The association is usually found in females. Nonimmune hemolysis has also been reported to be present in patients with Vitamin B12 deficiency[14],[15] and treatment with Vitamin B12 will lead to resolution of the hemolysis. Our patient's hemolytic anemia also responded to Vitamin B12 treatment “and” his hemoglobin improved on discharge at follow-up, he was found to have a stable hemoglobin.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.

  References Top

Bizzaro N, Antico A. Diagnosis and classification of pernicious anemia. Autoimmun Rev 2014;13:565-8.  Back to cited text no. 1
Hunt A, Harrington D, Robinson S. Vitamin B12 deficiency. BMJ 2014;349:g5226.  Back to cited text no. 2
Devitt KA, Lunde JH, Lewis MR. New onset pancytopenia in adults: A review of underlying pathologies and their associated clinical and laboratory findings. Leuk Lymphoma 2014;55:1099-105.  Back to cited text no. 3
Federici L, Henoun Loukili N, Zimmer J, Affenberger S, Maloisel F, Andrès E, et al. Update of clinical findings in cobalamin deficiency: Personal data and review of the literature. Rev Med Interne 2007;28:225-31.  Back to cited text no. 4
Vucelić V, Stancić V, Ledinsky M, Getaldić B, Sović D, Dodig J, et al. Combined megaloblastic and immunohemolytic anemia associated – A case report. Acta Clin Croat 2008;47:239-43.  Back to cited text no. 5
Rabinowitz AP, Sacks Y, Carmel R. Autoimmune cytopenias in pernicious anemia: A report of four cases and review of the literature. Eur J Haematol 1990;44:18-23.  Back to cited text no. 6
Oh R, Brown DL. Vitamin B12 deficiency. Am Fam Physician 2003;67:979-86.  Back to cited text no. 7
Selwyn JG, Alexander SS. A positive coombs reaction in pernicious anemia. Br Med J 1951;1:564-5.  Back to cited text no. 8
Rubio F Jr., Burgin L. Hemolytic disease complicated by pernicious anemia; report of two cases. Bull Tufts N Engl Med Cent 1957;3:77-85.  Back to cited text no. 9
Willoughby ML, Pears MA, Sharp AA, Shields MJ. Megaloblastic erythropoiesis in acquired hemolytic anemia. Blood 1961;17:351-6.  Back to cited text no. 10
Forshaw J, Harwood L. The direct antiglobulin (coombs) test in megaloblastic anaemia. J Clin Pathol 1965;18:119-20.  Back to cited text no. 11
Salvidio E, Venzano C, Boccaccio P, Ravazzolo R, Gaetani GF, Ajmar F. Pernicious anaemia followed by autoimmune haemolytic anaemia. Proc R Soc Med 1975;68:421-2.  Back to cited text no. 12
Nel AE. Primary acquired hypogammaglobulinaemia complicated by antibody-mediated haemolysis and pernicious anaemia. A case report. S Afr Med J 1983;64:326-8.  Back to cited text no. 13
Baba AA, Maharaj D. Hypocalcaemia in autoimmune haemolytic anaemia and pernicious anaemia. Postgrad Med J 1988;64:61-2.  Back to cited text no. 14
Pelosio A, Girelli G, Arista MC, Galassi A, Longhi C, Massini R. Pernicious anemia, vitiligo and positive antiglobulin test: An unusual association. Haematologica 1989;74:499-501.  Back to cited text no. 15


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