Hereditary and Metabolic Diseases of the Central Nervous System in Adults
Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw in Hankey's Clinical Neurology, 2020
This is less common, and has a wide variation in onset. Infancy is the most common presentation with severe failure to thrive and megaloblastic anemia. Hypotonia, seizures, and developmental delay or decline occur. Adult presentation varies widely: Weakness.Megaloblastic anemia.Psychosis and mental status changes.Significant thrombophilia.Hemolytic uremic syndrome.Optic nerve atrophy.
Vitamins
Frank A. Barile in Barile’s Clinical Toxicology, 2019
Pteroylglutamic acid (folate) is found in leafy vegetables, organ meats, and yeast. Physiologically, folic acid is required for nucleoprotein synthesis and the maintenance of hematopoiesis. It is converted intracellularly to tetrahydrofolic acid, which acts as a cofactor in the biosynthesis of purines and thymidylates of nucleic acids. Consequently, deficiency of folic acid (along with vitamin B12) is often seen during pregnancy and in malabsorption conditions and is responsible for defective DNA synthesis. The condition is manifested by the production of enlarged immature red cells characteristic of megaloblastic anemia. Although folic acid is relatively nontoxic, some allergic, central nervous system (CNS), and GI reactions have been noted with large doses (Table 22.4).
Vitamin B12
Judy A. Driskell, Ira Wolinsky in Sports Nutrition, 2005
Many of the hematologic changes in B12 deficiency are identical to those in folate deficiency, so are not true indicators of status of the individual vitamins. Megaloblastic changes in the bone marrow plus macroovalocytes and neutrophilic hypersegmentation in the peripheral blood are indicators of megaloblastic anemia, resulting from either folate or B12 deficiency. Hence, laboratory methods are needed to distinguish the two types of deficiency — measurements of serum and red cell folate and of serum vitamin B12 are needed to ascertain the cause of the macrocytic anemias. A wide range of neurologic signs and symptoms can indicate diminished cobalamin status. These include paresthesias of the extremities, loss of sensation, confusion, loss of memory and even, in severe cases, delusional psychosis. It is critically important to identify the cause of the hematologic abnormality because folate therapy for a cobalamin deficiency can reverse the megaloblastic symptomatology, but exacerbate the neurologic damage,10
Cobalamin and folic acid deficiencies presenting with features of a thrombotic microangiopathy: a case series
Published in Acta Clinica Belgica, 2022
Britt Ceuleers, Sofie Stappers, Jan Lemmens, Lynn Rutsaert
Physical examination was unremarkable except for obesity, extreme pale skin and mucosae. Vital signs were as follows: oxygen saturation 97%, heart rate 80/min and blood pressure 118/54 mmHg. Laboratory findings (Table 1) revealed a severe macrocytic anemia with findings consistent with hemolysis and a weak positive Direct Coombs test (strength 1+). Furthermore, there was a thrombocytopenia as well as a folate deficiency (<2.2 µg/L) with a normal vitamin B12 level (414 ng/L). Reticulocyte count was low and there was no evidence for leukocytopenia or lymphocytopenia. Additional laboratory findings showed normal kidney function (creatinine 0.84 mg/dl) and elevated iron levels. Peripheral blood smear findings did not detect schistocytes. Bone marrow examination confirmed megaloblastic anemia.
Etiology and clinico-hematological profile of pancytopenia: experience of a Mexican Tertiary Care Center and review of the literature
Published in Hematology, 2019
César Jonathan Vargas-Carretero, Omar Eduardo Fernandez-Vargas, Ana Lucía Ron-Magaña, José Alejandro Padilla-Ortega, Carlos Silvestre Ron-Guerrero, Esperanza Barrera-Chairez
This suggests that B12 deficiency could be the main cause of megaloblastic anemia in developing countries, as supported by a paper published in 2014 in an Indian population in which the authors found that most cases of macrocytic anemia were attributed to B12 deficiency, while almost 50% of cases with either microcytic or normocytic anemia were accompanied with cyanocobalamin deficiency [30]. Additionally, a relative excess of folic acid in comparison to B12 seems to detonate a more severe neurological and psychiatric symptoms, therefore, accurate diagnosis is important [27,30]. Moreover, B12 deficiency could likely be nutritional, since a study [31] demonstrated that only 3.9% of patients with macrocytosis had parietal cell autoantibodies. Nonetheless, a study found no clear correlation between vitamin levels, either folate or cobalamin, and the severity of anemia. This suggests that other factors influence its development and strain the need of performing further research in this topic [32].
Vitamin B12 deficiency mimicking acute leukemia
Published in Baylor University Medical Center Proceedings, 2019
Manojna Konda, Abhijit Godbole, Soumya Pandey, Appalanaidu Sasapu
Vitamin B12 deficiency is easily treatable but is often underrecognized.7 Its symptoms can be clinically subtle, with hematological abnormalities ranging from an incidentally discovered increase in mean corpuscular volume in asymptomatic patients to full-blown megaloblastic anemia.3 Less commonly, patients have life-threatening hematological manifestations including pancytopenia and hemolytic anemia.6 The patient discussed in this case report had vitamin B12 deficiency with macrocytosis, pancytopenia, and concurrent hemolysis (elevated lactate dehydrogenase and indirect bilirubin and low haptoglobin). The patient also had a low reticulocyte count, indicating an inadequate bone marrow response to the anemia. Hemolysis in patients with vitamin B12 deficiency has been attributed to intramedullary destruction of red blood cells due to ineffective erythropoiesis.
Related Knowledge Centers
- Anemia
- Azathioprine
- DNA Replication
- Folate Deficiency
- Trimethoprim
- Vitamin B12 Deficiency
- Vitamin Deficiency
- Red Blood Cell
- Cell Cycle
- Macrocytic Anemia