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Objectives: In this study, we aimed to explore the clinical characteristics of patients with megaloblastic anemia and pancytopenia., Methods: Data on patient characteristics, laboratory examinations, clinical manifestations, and associated diseases were collected from Changzhou Hospital of Traditional Chinese Medicine. The participants were divided into two groups according to routine blood test results: megaloblastic anemia patients with pancytopenia (Group A) and megaloblastic anemia patients with simple anemia (Group B)., Results: The number of patients with fever and bleeding in Group A was much higher than that in Group B. Inpatient days and hospitalization costs in Group A were higher than those in Group B. White blood cell count, red blood cell count, haemoglobin level, and platelet count in Group A were lower than those in Group B. There were no significant differences in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), and serum levels of lactate dehydrogenase (LDH), total bilirubin (TBIL), direct bilirubin (DBIL), indirect bilirubin (IBIL), albumin (ALB), vitamin B12, folic acid, and ferritin between the two groups. The incidence of associated diseases, particularly pulmonary infections, was significantly higher in Group A than in Group B. There was no significant difference in the degree of bone marrow hyperplasia between the two groups., Conclusion: Patients with pancytopenia and megaloblastic anemia often developed infection and bleeding, which caused more severe anemia, higher hospitalization costs, and longer inpatient days. Early diagnosis and active treatment are required to reduce patient complications and costs.

Background: Megaloblastic anemia is a subtype of anemia with increased red blood cell volume. These megaloblastic cells can be easily destroyed in the bone marrow and spleen, leading to ineffective hematopoiesis. Insulin-degrading enzymes (IDE) in erythrocytes can break down the insulin into amino acid fragments; thus, when hemolysis occurs, IDE can be released into the blood, resulting in low insulin measurement values., Methods: This article reports a case of false insulin test results due to the hemolysis resulting from megaloblastic anemia., Results: The patient's first fasting glucose results indicated that the glucose and C-peptide levels were within the normal range while her insulin level was abnormally low. After hemolysis was corrected, the relevant indicators were re-evaluated and all the results were normal., Conclusions: This article reports a patient diagnosed with megaloblastic anemia, whose dysmorphic erythrocytes cause severe extravascular hemolysis. It was the occurrence of hemolysis that the IDE released into the blood, leading to the abnormal insulin test result.

Inherited disorders of cobalamin (Cbl, vitamin B12) metabolism are rare causes of megaloblastic anemia and neurologic abnormalities. More prevalent in certain ethnic groups, these disorders occur despite adequate Cbl intake and usually result from abnormal vitamin cell transport or processing. Cubilin (CUBN, intrinsic factor-cobalamin receptor) is the intestinal receptor for the endocytosis of intrinsic factor-vitamin B12. Its gene is localized to chromosome 10p13 and mutations involving CUBN have been described in patients with congenital megaloblastic anemia. In this report, we describe a novel CUBN pathogenic variant in a child with megaloblastic anemia., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

A rare cause of megaloblastic anemia (MA) is thiamine-responsive megaloblastic anemia (TRMA), a genetic disorder caused by mutations in SLC19A2 (encoding THTR1), a thiamine transporter. The study objectives were to (1) functionally characterize selected TRMA-associated SLC19A2 variants and (2) determine whether current prescription drugs associated with drug-induced MA (DIMA) may act via inhibition of SLC19A2. Functional characterization of selected SLC19A2 variants was performed by confocal microscopy and isotopic uptake studies of [3H]-thiamine in HEK293 cells. Sixty-three drugs associated with DIMA were screened for SLC19A2 inhibition in isotopic uptake studies. Three previously uncharacterized SLC19A2 variants identified in TRMA patients exhibited disrupted localization to the plasma membrane along with near-complete loss-of-function. Ten of 63 drugs inhibited SLC19A2-mediated thiamine transport ≥ 50% at screening concentrations; however, with the exception of erythromycin, none was predicted to inhibit SLC19A2 at clinically relevant unbound plasma concentrations. Data from electronic health records revealed reduced levels of thiamine pyrophosphate (TPP) in patients prescribed erythromycin, consistent with inhibition of SLC19A2-mediated thiamine transport. Here, we confirmed the role of three SLC19A2 variants in TRMA pathology. Additionally, we report that inhibition of SLC19A2 is a potential, but uncommon mechanism for DIMA.

Homocysteine (Hcy) is methylated by methionine synthase to form methionine with methyl-cobalamin as a cofactor. The reaction demethylates 5-methyltetrahydrofolate to tetrahydrofolate, which is required for DNA and RNA synthesis. Deficiency of either of the cobalamin (Cbl) and/or folate cofactors results in elevated Hcy and megaloblastic anemia. Elevated Hcy is a sensitive biomarker of Cbl and/or folate status and more specific than serum vitamin assays. Elevated Hcy normalizes when the correct vitamin is given. Elevated Hcy is associated with alcohol use disorder and drugs that target folate or Cbl metabolism, and is a risk factor for thrombotic vascular disease. Elevated methionine and cystathionine are associated with liver disease. Elevated Hcy, cystathionine, and cysteine, but not methionine, are common in patients with chronic renal failure. Higher cysteine predicts obesity and future weight gain. Serum S-adenosylhomocysteine (AdoHcy) is elevated in Cbl deficiency and chronic renal failure. Drugs that require methylation for catabolism may deplete liver S-adenosylmethionine and raise AdoHcy and Hcy. Deficiency of Cbl or folate or perturbations of their metabolism cause major changes in sulfur amino acids., (© The Author(s) 2020. Published by Oxford University Press on behalf of the American Society for Nutrition.)

Thiamine-responsive megaloblastic anaemia (TRMA) is a syndrome associated with megaloblastic anaemia, diabetes mellitus and sensorineural deafness, due to mutations in the SLC19A2gene, which codes for a thiamine carrier protein. Oral thiamine supplementation is the main treatment. We report the case of a 19-year-old man known for TRMA, who presented in the emergency department with bicytopenia (haemoglobin 5,4 g/dL, thrombocytes 38×10 9 /L) revealed by dyspnea and chest pain. Investigations excluded bleeding, hemolysis, coagulopathy and iron deficiencies. A recent infection and an acute coronary syndrome have also been eliminated. We later found out that thiamine treatment had been discontinued three months before, due to general confinement in Tunisia during the COVID-19 pandemic. Parenteral administration of 100 mg of thiamine daily resulted in the recovery of haematopoiesis within three weeks., Competing Interests: The authors declare no competing interests., (Copyright: Nourelhouda Nouira et al.)

Megaloblastic anaemia due to vitamin B12 and folic acid deficiency is uncommon in infancy and rarely reported in infants below 3 months of age. We hereby report a case of megaloblastic anaemia in a 9-weeks old infant having fever from 7th week of life. Blood picture showed pancytopenia and diagnosis was confirmed on bone marrow biopsy and serum level of vitamins. Patient positively responded to vitamin B12 and folic acid supplementation. Infants with pancytopenia even younger than 2 months, should also be investigated for vitamin B12 and folate deficiency. Mother of the baby was not antenatally investigated for anaemia. Prompt antenatal diagnosis and treatment of mothers can reduce the incidence in the infants.

We describe 2 children with cobalamin G disease, a disorder of vitamin B 12 metabolism with normal serum B 12 levels. They presented with megaloblastic anemia progressing rapidly to severe thrombotic microangiopathy. In infants presenting with acute thrombotic microangiopathy, cobalamin disorders should be considered early as diagnosis and targeted treatment can be lifesaving., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Key Points: Folate (folic acid) deficiency and mutations in folate-related genes in humans result in megaloblastic anaemia. Folate metabolism, which requires the enzyme methionine synthase reductase (MTRR), is necessary for DNA synthesis and the transmission of one-carbon methyl groups for cellular methylation. In this study, we show that the hypomorphic Mtrr gt/gt mutation in mice results in late-onset and sex-specific blood defects, including macrocytic anaemia, extramedullary haematopoiesis and lymphopenia. Notably, when either parent carries an Mtrr gt allele, blood phenotypes result in their genetically wildtype adult daughters, the effects of which are parent specific. Our data establish a new model for studying the mechanism of folate metabolism in macrocytic anaemia aetiology and suggest that assessing parental folate status might be important when diagnosing adult patients with unexplained anaemia., Abstract: The importance of the vitamin folate (also known as folic acid) in erythrocyte formation, maturation and/or longevity is apparent since folate deficiency in humans causes megaloblastic anaemia. Megaloblastic anaemia is a type of macrocytic anaemia whereby erythrocytes are enlarged and fewer in number. Folate metabolism is required for thymidine synthesis and one-carbon metabolism, though its specific role in erythropoiesis is not well understood. Methionine synthase reductase (MTRR) is a key enzyme necessary for the progression of folate metabolism since knocking down the Mtrr gene in mice results in hyperhomocysteinaemia and global DNA hypomethylation. We demonstrate here that abnormal folate metabolism in mice caused by Mtrr gt/gt homozygosity leads to haematopoietic phenotypes that are sex and age dependent. Specifically, Mtrr gt/gt female mice displayed macrocytic anaemia, which might be due to defective erythroid differentiation at the exclusion of haemolysis. This was associated with increased renal Epo mRNA expression, hypercellular bone marrow, and splenic extramedullary haematopoiesis. In contrast, the male response differed since Mtrr gt/gt male mice were not anaemic but did display erythrocytic macrocytosis and lymphopenia. Regardless of sex, these phenotypes were late onset. Remarkably, we also show that when either parent carries an Mtrr gt allele, a haematological defect results in their adult wildtype daughters. However, the specific phenotype was dependent upon the sex of the parent. For instance, wildtype daughters of Mtrr +/gt females displayed normocytic anaemia. In contrast, wildtype daughters of Mtrr +/gt males exhibited erythrocytic microcytosis not associated with anaemia. Therefore, abnormal folate metabolism affects adult haematopoiesis in an age-, sex- and parent-specific manner., (© 2018 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Introduction: Pancytopenia is a relatively common hematological entity and is a manifestation of many illnesses which can be life threatening at times. The severity of pancytopenia and the underlying pathology determine the management and prognosis. This study was conducted to evaluate hematological and bone marrow findings in patients presenting with pancytopenia., Methods: A prospective observational study was conducted in Department of Pathology, Manipal College of Medical Sciences, Pokhara from January 2011 to December 2016. Clinical and hematological parameters including bone marrow aspiration and biopsy were evaluated in all patients who presented with pancytopenia., Results: Among 138 cases studied, patients' age ranged from 2 to 82 years with a mean age of 43.95 years, and there was male predominance. Most of the patients presented with generalized weakness, pallor, dypnoea and fever. Hypoplastic marrow was seen in 38 (27.5%) cases, followed by 26 (18.8%) cases of megaloblastic anemia and 19 (13.76%) cases of acute leukemia. Other findings included one case each of hemophagocyosis, leishmaniasis, plasmodium vivex malaria and metastatic carcinoma., Conclusions: This study highlights that pancytopenia is a common hematological problem and that the study of detailed primary hematological investigations along with bone marrow study in patients with pancytopenia will help to identify the cause for further planning and management.

Background: The association between obesity and different types of anemia remained uncertain. The present study aimed to assess the relation between obesity parameters and the occurrence of iron deficiency anemia and also megaloblastic anemia among Iranian population., Methods and Materials: This cross-sectional study was performed on 1252 patients with morbid obesity that randomly selected from all patients referred to Clinic of obesity at Rasoul-e-Akram Hospital in 2014. The morbid obesity was defined according to the guideline as body mass index (BMI) equal to or higher than 40 kg/m2. Various laboratory parameters including serum levels of hemoglobin, iron, ferritin, folic acid, and vitamin B12 were assessed using the standard laboratory techniques., Results: BMI was adversely associated with serum vitamin B12, but not associated with other hematologic parameters. The overall prevalence of iron deficiency anemia was 9.8%. The prevalence of iron deficiency anemia was independent to patients' age and also to body mass index. The prevalence of vitamin B12 deficiency was totally 20.9%. According to the multivariable logistic regression model, no association was revealed between BMI and the occurrence of iron deficiency anemia adjusting gender and age. A similar regression model showed that higher BMI could predict occurrence of vitamin B12 deficiency in morbid obese patients., Conclusion: Although iron deficiency is a common finding among obese patients, vitamin B12 deficiency is more frequent so about one-fifth of these patients suffer vitamin B12 deficiency. In fact, the exacerbation of obesity can result in exacerbation of vitamin B12 deficiency.

Objective: Transcobalamin II deficiency is one of the rare causes of inherited vitamin B12 disorders in which the patients have characteristically normal or high vitamin B12 levels related to the transport defect of vitamin B12 into the cell, ending up with intracellular cobalamin depletion and high homocysteine and methylmalonic acid levels., Materials and Methods: Herein, we describe the findings at presentation of four patients who were diagnosed to have transcobalamin II deficiency with novel mutations., Results: These patients with transcobalamin II deficiency were found to have novel mutations, of whom 2 had the same large deletion (homozygous c.1106+1516-1222+1231del)., Conclusion: Transcobalamin II deficiency should be considered in differential diagnosis of any infant with pancytopenia, failure to thrive, diarrhea, and vomiting.

Recent studies have focussed on the association between elevated homocysteine levels with megaloblastic changes and thromboembolic events, but the relationship between occult megaloblastosis (with normal haemoglobin levels) and ischaemic stroke has not been widely explored. The objective of this study is to establish a simple and economical marker for the detection of occult megaloblastosis at the community health care level in developing countries. A hundred patients who met the inclusion criteria were studied. At the 5% level of significance, the levels of cobalamin and folate were significantly lower, while the number of hypersegmented neutrophils on the peripheral smear was higher in patients from Group A (70 patients with high homocysteine) compared with the patients in Group B (30 patients with normal homocysteine). Forty-five (64.2%) of the 70 patients in Group A showed hypersegmentation of neutrophils in the peripheral smear. The high cost and difficulty in performing the vitamin assays limit their use as early markers of megaloblastosis. Hence, we conclude that in developing countries, the detection of hypersegmented neutrophils can be used at the primary healthcare level for early diagnosis of occult megaloblastosis, so that early therapeutic interventions with vitamins can prevent attacks of hyperhomocysteinemia-induced ischaemic stroke.

Objective: It was our aim to study the diagnostic significances of various dysplasia characteristics in myelodysplastic syndrome (MDS)., Methods: We analyzed 160 cases of primary MDS and a control group including 28 cases of paroxysmal nocturnal hemoglobinuria (PNH), 104 cases of idiopathic thrombocytopenic purpura (ITP), 53 cases of non-severe aplastic anemia (NSAA), 40 cases of megaloblastic anemia and 50 cases of infectious and autoimmune diseases. Peripheral blood smears and bone marrow morphology were reviewed., Results: There was no significant difference in the occurrence rates of a variety of dysplasias in three lineages among MDS, megaloblastic anemia and PNH; however, changes in qualities and quantities in three lineages between NSAA and MDS were significantly different. ITP and MDS showed statistical differences in multiple changes in myeloid and erythroid cells. Significant differences also existed in multiple changes in erythroid series and megakaryocytes between infectious and autoimmune diseases and MDS. Morphological abnormalities highly related with MDS included multinucleated erythroblasts, ringed sideroblasts, poikilocytosis and gigantocytes, pseudo-Pelger neutrophils, ring-shaped nucleus, and micromegakaryocytes., Conclusions: It is difficult to discriminate megaloblastic anemia and PNH from MDS by means of cell morphology. Different dysplasias of MDS have specific diagnostic values., (© 2013 S. Karger AG, Basel.)

The foundation of laboratory hematologic diagnosis is the complete blood count and review of the peripheral smear. In patients with anemia, the peripheral smear permits interpretation of diagnostically significant red blood cell (RBC) findings. These include assessment of RBC shape, size, color, inclusions, and arrangement. Abnormalities of RBC shape and other RBC features can provide key information in establishing a differential diagnosis. In patients with microcytic anemia, RBC morphology can increase or decrease the diagnostic likelihood of thalassemia. In normocytic anemias, morphology can assist in differentiating among blood loss, marrow failure, and hemolysis-and in hemolysis, RBC findings can suggest specific etiologies. In macrocytic anemias, RBC morphology can help guide the diagnostic considerations to either megaloblastic or nonmegaloblastic causes. Like all laboratory tests, RBC morphologies must be interpreted with caution, particularly in infants and children. When used properly, RBC morphology can be a key tool for laboratory hematology professionals to recommend appropriate clinical and laboratory follow-up and to select the best tests for definitive diagnosis., (© 2013 Blackwell Publishing Ltd.)

Cobalamin (vitamin B12) deficiency is a common cause of megaloblastic anemia in Western populations. Laboratory evaluation of megaloblastic anemia frequently includes the assessment of patient cobalamin and folate status. Current total serum cobalamin measurements are performed in the clinical laboratory with competitive binding luminescence assays, whose results may not always accurately reflect actual cobalamin stores. Surrogate markers of cobalamin deficiency such as methylmalonic acid and homocysteine have been utilized to improve diagnostic accuracy; however, the specificity of these tests by themselves is rather low. Measurement of the biologically active fraction of cobalamin, holotranscobalamin, has been proposed as a replacement for current total cobalamin assays. Although holotranscobalamin measurements appear to have slighter better sensitivity, the specificity of this assay remains to be determined. The relative merits and demerits of commonly available methods to assess cobalamin deficiency in patients with suspected megaloblastic anemia are discussed., (Copyright © 2013 Wiley Periodicals, Inc.)

Aim: To identify the incidence and etiology of anemia after gastrectomy in patients with long-term follow-up after gastrectomy for early gastric cancer., Methods: The medical records of those patients with early gastric adenocarcinoma who underwent curative gastrectomy between January 2006 and October 2007 were reviewed. Patients with anemia in the preoperative workup, cancer recurrence, undergoing systemic chemotherapy, with other medical conditions that can cause anemia, or treated during follow up with red cell transfusions or supplements for anemia were excluded. Anemia was defined by World Health Organization criteria (Hb < 12 g/dL in women and < 13 g/dL in men). Iron deficiency was defined as serum ferritin < 20 μg/dL. Vitamin B₁₂ deficiency was defined as serum vitamin B₁₂ < 200 pg/mL. Iron deficiency anemia was defined as anemia with concomitant iron deficiency. Anemia from vitamin B₁₂ deficiency was defined as megaloblastic anemia (mean cell volume > 100 fL) with vitamin B₁₂ deficiency. The profile of anemia over 48 mo of follow-up was analyzed., Results: One hundred sixty-one patients with gastrectomy for early gastric cancer were analyzed. The incidence of anemia was 24.5% at 3 mo after surgery and increased up to 37.1% at 48 mo after surgery. The incidence of iron deficiency anemia increased during the follow up and became the major cause of anemia at 48 mo after surgery. Anemia of chronic disease and megaloblastic anemia were uncommon. The incidence of anemia in female patients was significantly higher than in male patients at 12 (40.0% vs 22.0%, P = 0.033), 24 (45.0% vs 25.0%, P = 0.023), 36 (55.0% vs 28.0%, P = 0.004), and 48 mo (52.0% vs 31.0%, P = 0.022) after surgery. Patients with total gastrectomy showed significantly higher incidence of anemia than patients with subtotal gastrectomy at 48 mo after surgery (60.7% vs 31.3%, P = 0.008). The incidence of iron deficiency was significantly higher in female patients than in male patients at 6 (35.4% vs 13.3%, P = 0.002), 12 (45.8% vs 16.8%, P < 0.001), 18 (52.1% vs 22.3%, P < 0.001), 24 (60.4% vs 20.9%, P < 0.001), 36 (62.5% vs 29.2%, P < 0.001), and 48 mo (66.7% vs 34.7%, P = 0.001) after surgery., Conclusion: Anemia was frequent after gastrectomy for early gastric cancer, with iron deficiency being the major cause. Evaluation for anemia including iron status should be performed after gastrectomy and appropriate iron replacement should be considered.

Twenty cases of Dyphillobothrium pacificum (fish tapeworm) infections were prospectively studied to determine whether this tapeworm is associated with megaloblastic anemia, as commonly reported for D. latum infections. The most frequent symptoms were fatigue and mild abdominal pain, which were identified in approximately 66.6% of the 18 patients interviewed. Fourteen patients received treatment with niclosamide and all were cured. The other six patients spontaneously eliminated the tapeworms. One patient, who also had chronic diabetes and gastric atrophy, had low vitamin B12 levels and megaloblastic anemia. In all other patients, including three other patients with anemia, baseline vitamin B12 levels were in the reference range and did not significantly change when re-assessed three months later. Unlike D. latum, infection with D. pacificum is seldom associated with megaloblastic anemia or vitamin B12 deficit.

We report the case of a 7-month-old breast fed infant who presented with a nose bleed and bruises. Investigation showed severe nutritional B12 deficiency anemia with a pancytopenia. It is important to take the nutritional history of both the infant and the mother for early prevention and treatment.

Nutritional B12 deficiency in childhood is an uncommon disorder. Most cases are due to maternal insufficiency, resulting from deficient stores and intake, and is generally seen in exclusively breast fed infants. This report describes a breast-fed infant with megaloblastic anemia secondary to maternal vitamin B12 deficiency. We describe this patient to remind readers that B12 deficiency may cause severe pancytopenia and regression of motor functions. These patients can present with unexpected signs and symptoms, such as developmental delay and regression as in our patient. It is also important to take the nutritional history of both the child and the mother of early prevention and treatment. With early awareness and appropriate measures potentially irreversible neurologic damage can be prevented in the infant.

Background: Megaloblastic anemias are characterized by several hematopoietic cells with dysplastic nuclear morphology. The analyses of DNA ploidy and cell cycle of these cells are important to understand the property of such diseases., Methods: As laser scanning cytometry (LSC) is a useful tool to evaluate the morphology of the cells fixed on the slide glass together with the quantitative analysis of the fluorescence information of each cell by rapid scanning of the specimens, the authors examined the DNA ploidy and cell cycle of six cases with megaloblastic anemia using LSC., Results: Giant neutrophilic series such as giant metamyelocytes and giant band cells were found to have extraordinarily higher DNA ploidy, while hypersegmented neutrophils represented the normal diploid pattern like normal neutrophils. As to megaloblasts, cell cycle analysis showed that the proportion of the cells in S phase was increased as compared with the case of normal erythroblasts., Conclusions: The present study clearly demonstrates the abnormal aspects of the hematopoietic cells with megaloblastic anemia from the viewpoint of the DNA ploidy and cell cycle analyzed by the use of LSC., ((c) 2007 Clinical Cytometry Society)

Drug-induced anemia includes many kind of anemias with different mechanisms. Mechanisms of drug-induced anemia are divided into two groups, namely erythrocyte injury in peripheral blood and damage of erythroid progenitor cells or erythroblasts. Hemolytic anemias are included in the former and megaloblastic anemia, ringed sideroblastic anemia and pure red cell aplasia are included in the latter. When the drug induced anemia is suspected, complete blood cell count including reticulocyte count and examination of the blood smear and blood chemistry tests should be done. Also, history of the medication should be precisely taken. As for the treatment of drug-induced anemia, the responsible drug should be stopped immediately and individual therapy will be done if necessary.

Impaired methylation due to accumulation of S-adenosylhomocysteine (SAH) may contribute to the pathophysiology of cobalamin-deficient anemia. We assayed serum S-adenosylmethionine (SAM), SAH, total homocysteine (tHcy), and methylmalonic acid (MMA) in 15 subjects with cobalamin-deficient megaloblastic anemia and compared results with those of 19 subjects with anemia/pancytopenia due to other causes. Cobalamin-deficient subjects had a median hematocrit level of 20% and mean cell volume of 111.7 fL. The median serum cobalamin level was 37 pg/mL, MMA 3030 nmol/L, and tHcy 62.0 micromol/L. SAH was elevated in 13 of 15 subjects (median, 42 nmol/L) and the median SAM value was normal (103 nmol/L), but SAM/SAH ratio was low (2.5). The SAH was higher and SAM/SAH ratio was lower in cobalamin-deficient subjects compared with those with other anemias after excluding 4 patients with renal insufficiency. SAM concentrations were not low in cobalamin deficiency. Cobalamin injections corrected anemia, MMA, tHcy, SAM/SAH ratio, and SAH. Some hematologic variables were inversely correlated with SAH and cobalamin but not tHcy or MMA. In conclusion, serum SAH is elevated in cobalamin-deficient subjects with megaloblastic anemia and corrects with parenteral cobalamin therapy.

We report here a case of megaloblastic anaemia in late pregnancy, which leads us to question whether folate supplements should be recommended in the UK routinely throughout pregnancy and not just in the preconception period and first trimester.

We present a case of intracellular vitamin B12 deficiency presenting with confusion, subacute combined degeneration of the cord, megaloblastic anaemia and intrinsic factor antibodies in the serum. Diagnosis was delayed by a normal serum B12 level and was confirmed by a grossly elevated serum homocysteine. There was a dramatic response to steroids. The patient was heterozygous for the transcobalamin (TC) II polymorphism 776C --> G. This case demonstrates the importance of functional assessment of intracellular B12 activity (e.g. serum homocysteine) in excluding B12 deficiency, the role of steroids in pernicious anaemia and a possible clinical correlation of a TCII polymorphism.

Background: There is increased worldwide concern about the consequences of folic acid and vitamin B12 deficiencies on health, which include megaloblastic anemia, neural tube defects and cardiovascular disease., Objective: This study intended to determine the prevalence of folic acid and vitamin B12 deficiencies in vulnerable groups in labor and poor socioeconomic strata of the Venezuelan population., Methods: A total of 5658 serum samples were processed to determine folic acid and vitamin B12 concentrations. The study involved three surveys performed during 2001-2002 and included infants, children, adolescents and pregnant women from labor and poor socioeconomic strata of the population. The method used was a radio immunoassay designed for the simultaneous measurement of serum folic acid and vitamin B12., Results: The prevalence of folic acid deficiency was higher than 30% for all groups studied, reaching 81.79% in adolescents. Vitamin B12 deficiency was 11.4% in samples collected nationwide, but there was also a similar prevalence of high serum levels. The prevalence of folic acid and vitamin B12 deficiencies in pregnant women reached 36.32 and 61.34%, respectively., Conclusion: This work shows that there is a high prevalence of folic acid deficiency, especially in women of reproductive age, pregnant adolescents and in the whole population studied in Vargas state. This situation requires immediate intervention as supplementation or food fortification programs.

Objective: Megaloblastosis (i.e., megaloblastic transformation of erythroid precursor cells in the bone marrow) is the cytomorphological hallmark of megaloblastic anemia resulting from vitamin B12 and folate deficiency. It is characterized by a finely stippled lacy pattern of nuclear chromatin, which is believed to be an expression of deranged cellular DNA synthesis. However, the molecular basis of these cytomorphological aberrations still remains obscure. The current presentation describes the results of our studies on some molecular events associated with the development of megaloblastosis., Methods: Transmission electron microscopy was used to study megaloblasts as well as DNA fibers extracted from megaloblastic and normoblastic bone marrows with and without treatment with proteinase K during the extraction procedure; cellular DNA synthesis in bone marrow cultures was studied by incorporation of 3H-thymidine and deoxyuridine suppression test, while histone biosynthesis in bone marrow cells was studied by in vitro incorporation of 3H-tryptophan, 3H-lysine and 3H-arginine into histones., Results: Derangement of DNA synthesis occurred due to an impaired de novo pathway of thymidylate synthesis in both vitamin-B12- and folate-deficient human megaloblastic bone marrows as well as in the bone marrows of rhesus monkeys and rats with experimentally induced folate deficiency. Interestingly, folate-deficient monkeys developed frank megaloblastic bone marrows, but folate-deficient rats did not. On the other hand, megaloblastic changes in the bone marrow of human patients with myelodysplastic syndrome and erythroleukemia were not associated with this DNA synthetic abnormality. Biosynthesis of predominantly arginine-rich histones in megaloblastic bone marrows was markedly reduced as compared to normoblastic bone marrows, which was consistently associated with elongation and despiralization of chromosomes and finely stippled nuclear chromatin in megaloblasts., Conclusion: The impaired biosynthesis of predominantly arginine-rich nuclear histones appeared to be a common molecular event (a denominator) underlying the development of megaloblastosis with or without abnormal DNA synthesis., (Copyright 2005 S. Karger AG, Basel)

Megaloblastic anaemias (MA) are frequently associated with haemolysis. The pathogenesis of these finding is not clear, but it is thought to depend on the greater destruction of abnormal and fragile megaloblastic erythrocytes. Vitamin B(12) and folate deficiencies are the commonest cause of MA; these deficiencies may simultaneously induce a significant alteration in homocysteine metabolism leading to hyperhomocysteinemia. Blood cells have enzymes involved in homocysteine metabolism. Considering the possible effects of hyperhomocysteinemia in erythrocyte toxicity (due to oxidative damage and/or to interaction with sulfhydryl residues of structural and enzymatic proteins), the aim of our study was to evaluate (1) the homocysteine blood cells production in patients with MA due to vitamin B(12) and folate deficiency and (2) the possible role and mechanism of hyperhomocysteinemia in MA haemolysis. After incubation at 37 degrees C, blood samples from MA patients showed higher and significant levels of Hcy, LDH, lipid peroxidation parameters (MDA), and ghost protein-bound Hcy than controls. Haemolysis (%) was higher in MA patients than controls and was significantly correlated with Hcy accumulation in the medium, lipid peroxidation indices and ghost protein-bound Hcy. No significant (or significantly lower) alterations through time in considered parameters were observed in the corresponding samples incubated at 4 degrees C or in samples incubated with methionine-free medium (lower Hcy production). Our data, deriving from an in vitro experience, suggest a possible role of Hcy accumulation due to vitamin B(12) and folate deficiencies in haemolysis associated to MA due to vitamin deficiency.

The results of examinations of reticulocytes in blood samples of 12 patients with the confirmed diagnosis of B12-deficit anemia and of 20 virtually healthy subjects (control group) by means of the GEN-S hematological analyzer (Beckman-Coulter) are described in the paper. Typical changes of the reticulocyte parameters are defined and their dynamics (with treatment by Vitamin B12) is studied. It was established that the additional parameters of the reticulocyte analysis, characterizing the quantity of immature reticulocytes and the fraction of immature reticulocytes, increase by 3 days before the total quantity of erythrocytes increases, which means that the above parameters can be used earlier as criteria in evaluating the treatment efficiency.

Introduction: The abnormalities in iron metabolism associated with megaloblastic anemia are rapidly reversed by B(12) therapy in pernicious anemia (PA). Although non-tranferrin-bound plasma iron (NTBI) was previously shown to be associated with severe iron overload, its origin is unknown., Methods and Results: Four patients with PA were studied before and after B(12) treatment. NTBI was measured by a fluorescence-based one-step assay. All patients had very high transferrin saturation, NTBI values ranging from 1.1 to 2.6 micromol/l and normal serum ferritins. B(12) treatment resulted in the disappearance of NTBI and normalization of transferrin saturation within 22-42 h., Conclusions: The prompt disappearance of NTBI following B(12) therapy implicates catabolic iron derived from ineffective erythropoiesis as the major source of NTBI in untreated PA and possibly in thalassemia major and sideroblastic anemia. Our findings offer further insight into the pathogenesis of NTBI in diseases associated with abnormal erythropoiesis.

Background: Cobalamin (vitamin B12) deficiency, the most common cause of megaloblastic anemia, is treated with intramuscular (IM) cobalamin. It has been suggested by some investigators that oral (p.o.) cobalamin treatment may be as effective in the treatment of this condition, with the advantages of ease of administration and lower cost., Objective: This study assessed the effects and cost of p.o. versus i.m. cobalamin treatment in patients with megaloblastic anemia due to cobalamin deficiency., Methods: This was a 90-day, prospective, randomized, open-label study conducted at the Division of Hematology, Department of Internal Medicine, Adnan Menderes University Research and Practice Hospital (Aydin, Turkey). Patients aged > or =16 years with megaloblastic anemia due to cobalamin deficiency were randomized to receive 1000-microg cobalamin p.o. once daily for 10 days (p.o. group) or 1000-microg cobalamin i.m. once daily for 10 days (i.m. group). After 10 days, both treatments were administered once a week for 4 weeks, and after that, once a month for life. Patients were assessed for the presence of reticulocytosis between treatment days 5 and 10 until it was detected. Therapeutic effectiveness was assessed by measuring hematologic parameters on days 0, 10, 30, and 90 and serum vitamin B12 concentration on days 0 and 90. The Mini-Mental State Examination was used before and after the B12 therapy for cognitive function assessment and 125-Hz diapozone was used for vibration threshold testing. Neurologic sensory assessment, including soft-touch and pinprick examinations, was used to identify neuropathy at baseline and study end. Tolerability was assessed using laboratory tests and patient interview. Cost was assessed using the cost of the study drug and of the injection., Results: Sixty patients completed the study 26 in the p.o. group (16 men, 10 women; mean [SD] age, 60 [15] years) and 34 in the i.m. group (17 men, 17 women; mean [SD] age, 64 [10] years). Reticulocytosis was observed in all patients. In the p.o. group, at days 30 and 90, all hematologic parameters changed significantly versus day 0 (mean hemoglobin levels increased [both P<0.001]; mean corpuscular volume decreased [both P<0.001]; mean white blood cell count increased [day 30, P<0.01; day 90, P<0.001]; and mean platelet count increased [both P<0.001]). The mean serum vitamin B12 concentration increased significantly from day 0 to 90 (P<0.001). These hematologic parameters and the recovery patterns were similar between the 2 groups. Neurologic findings included sensitive peripheral neuropathy in 9 patients (15.0%), alteration of cognitive function (loss of memory, impaired concentration) in 7 patients (11.7%), and loss of sense of vibration in 5 patients (8.3%). Neurologic improvement was detected in 7 of 9 patients (77.8%) in the p.o. group and 9 of 12 patients (75.0%) in the i.m. group at day 30., Conclusions: In this study of patients with megaloblastic anemia due to cobalamin deficiency, p.o. cobalamin treatment was as effective as i.m. cobalamin treatment. P.o. treatment also was better tolerated and less expensive compared with IM treatment. However, because of the small sample size and the short term of this study, further long-term studies are needed to determine the efficacy of p.o. cobalamin treatment.

Background: Transcobalamin II is a serum transport protein for vitamin B12. Small variations in TC-II affinity were recently linked to a high homocysteine level and increased frequency of neural tube defects. Complete absence of TC-II or total functional abnormality causes tissue vitamin B12 deficiency resulting in a severe disease with megaloblastic anemia and immunologic and intestinal abnormalities in the first months of life. This condition was described in hereditary autosomal-recessive form. Low serum TC-II without any symptoms or clinical significance was noted in relatives of affected homozygotes., Objectives: To study 23 members of a four-generation family with hereditary vitamin B12 deficiency and neurologic disorders., Methods: Thorough neurologic, hematologic and family studies were supplemented by transcobalamin studies in 20 family members., Results: Partial TC-II deficiency was found in 19 subjects. Apo TC-II (free TC-II unbound to vitamin B12) and total unsaturated B12 binding capacity were low in all tested individuals but one, and holo TC-II (TC-II bound by vitamin B12) was low in all family members. The presentation of the disease was chronic rather than acute. Early signs in children and young adults were dyslexia, decreased IQ, vertigo, plantar clonus and personality disorders. Interestingly, affected children and young adults had normal or slightly decreased serum vitamin B12 levels but were not anemic. Low serum B12 levels were measured in early adulthood. In mid-late adulthood megaloblastic anemia and subacute combined degeneration of the spinal cord were diagnosed. Treatment with B12 injections resulted in a significant improvement. The pedigree is compatible with an autosomal-dominant transmission. This family study suggests a genetic heterogeneity of TC-II deficiency., Conclusions: We report the first family with a hereditary transmitted condition of low serum TC-II (partial TC-II deficiency) associated with neurologic and mental manifestations in childhood. Partial TC-II deficiency may decrease the amount of stored cobalamin, resulting in increased susceptibility to impaired intestinal delivery of cobalamin and predisposing to clinically expressed megaloblastic anemia at a later age. Partial TC-II deficiency should be suspected in families with megaloblastic anemia and in individuals with neurologic and mental disturbances--despite normal serum vitamin B12 levels. Low serum UBBC and apo TC-II should confirm the diagnosis. Early vitamin B12 therapy may prevent irreversible neurologic damage.

Transcobalamin (TC), a vitamin B12 (cobalamin, Cbl) binding protein in plasma, promotes the cellular uptake of the vitamin by receptor-mediated endocytosis. Inherited TC deficiency is an autosomal recessive disorder characterized by megaloblastic anaemia caused by cellular vitamin B12 depletion. It may be accompanied by neurological complications, including a delay in psychomotor and mental development. This report describes three sisters with inherited TC deficiency resulting from a splicing defect in the TC gene. A point mutation was identified in intron 3 splice site of the TC gene that activates a cryptic splice site in exon 3. The transcript generated has an in-frame deletion of 81 nucleotides and the resulting truncated protein is unstable and not secreted by the cells. Until now, genetic studies have been reported in only five patients with TC deficiency and the molecular defect was different in each of them, which gives evidence for a genetic heterogeneity of the disease.

Megaloblastic anaemia and aplastic anaemia are important causes of pancytopenia in India. Since both may have presence of macrocytes, peripheral smear examination alone may pose a difficulty in distinction between the two in the absence of macro-ovalocytes and hypersegmented neutrophils. The present study was conducted to evaluate the role of red cell indices in differentiation between macrocytosis of aplastic anaemia and megaloblastic anaemia. Haemogram from 25 cases each of biopsy proven megaloblastic anaemia and aplastic anaemia were reviewed. It was observed that MCV was greater than 97 fl in 15 cases of aplastic anemia (mean MCV 109.7 fl), and 25 cases of megaloblastic anaemia (mean MCV 113.2 fl). Hb, MCV & MCHC were comparable in the two groups. However, mean RDW in megaloblastic anaemia (mean 87.7 fl) was significantly higher than those in aplastic anaemia (mean 71.4 fl). The difference in RDW of patients with megaloblastic anaemia and aplastic anaemia was statistically significant. We conclude that RDW can be of help to differentiate between the two conditions.

In rats, in contrast with human subjects who develop megaloblastic anaemia due to vitamin B12 deficiency, haematological abnormalities with anaemia were not observed under normoxic conditions even though plasma vitamin B12 concentration was reduced to <15 % of a normal concentration by depleting dietary vitamin B12. To elucidate whether erythropoiesis was affected by vitamin B12 deficiency in rats, these vitamin B12-deficient rats were exposed to hypoxia (10.5 % O2) to stimulate erythropoiesis. In the vitamin B12-sufficient control rats, erythrocyte count was significantly (P<0.05) increased 1 week after starting the hypoxic exposure. However, the hypoxia-induced erythropoiesis was affected by vitamin B12 deficiency, and no significant increase in the erythrocyte count was observed even after 6-week exposure to hypoxia in the vitamin B12-deficient rats. In the vitamin B12-deficient rats in hypoxia, erythrocytes became abnormally enlarged, and haemoglobin concentration in peripheral blood was increased in proportion to the increase of mean corpuscular volume. However, the level of the increase in the haemoglobin concentration was significantly (P<0.05) lower in the vitamin B12-deficient rats compared with that in the -sufficient controls. In addition, in the vitamin B12-deficient rats, in contrast to the -sufficient rats, serum erythropoietin concentration was not normalized even after 6-week exposure to hypoxia. These results indicate that a megaloblastic anaemia-like symptom is induced when the vitamin B12-deficient rats are exposed to hypoxia.