Diagnostic Considerations

In a patient with combined folate and vitamin B-12 deficiency, if only the folate deficiency is recognized, folic acid supplementation may be sufficient to drive the production of active 5 methyl tetrahydrofolate (THF) in the absence of vitamin B-12. This results in improvement of the anemia but does not result in improvement of the function of other pathways dependent on B-12.

Clinically, this is apparent as a resolution of megaloblastic anemia, but with progressive dementia and long-tract neurologic deficits. This situation can be avoided by measuring levels of both vitamins, then evaluating and treating both deficiencies, if found.

Other conditions to consider include the following:

Aplastic anemia
Celiac disease
Ecchymoses
Granulocytopenia
Hyposplenism
Myeloproliferative disorders
Neutropenia
Pancytopenia
Tapeworm infection (cestodiasis)
Imerslund-Grasbeck disease
Thiamine-responsive megaloblastic anemia^{[2, 3]}

Go to Pediatric Chronic Anemia, Anemia of Prematurity, Donath-Landsteiner Hemolytic Anemia, Pediatric Acute Anemia, and Fanconi Anemia for complete information on these topics.

Differential Diagnoses

Workup

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Media Gallery

Bone marrow aspirate from a patient with untreated pernicious anemia. Megaloblastic maturation of erythroid precursors is shown. Two megaloblasts occupy the center of the slide with a megaloblastic normoblast above. Photo courtesy of Marcel E Conrad, MD.

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Author

James L Harper, MD Associate Professor, Department of Pediatrics, Division of Hematology/Oncology and Bone Marrow Transplantation, Associate Chairman for Education, Department of Pediatrics, University of Nebraska Medical Center; Associate Clinical Professor, Department of Pediatrics, Creighton University School of Medicine; Director, Continuing Medical Education, Children's Memorial Hospital; Pediatric Director, Nebraska Regional Hemophilia Treatment Center

James L Harper, MD is a member of the following medical societies: American Society of Pediatric Hematology/Oncology, American Federation for Clinical Research, Council on Medical Student Education in Pediatrics, Hemophilia and Thrombosis Research Society, American Academy of Pediatrics, American Association for Cancer Research, American Society of Hematology

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Steven K Bergstrom, MD Department of Pediatrics, Division of Hematology-Oncology, Kaiser Permanente Medical Center of Oakland

Steven K Bergstrom, MD is a member of the following medical societies: Alpha Omega Alpha, Children's Oncology Group, American Society of Clinical Oncology, International Society for Experimental Hematology, American Society of Hematology, American Society of Pediatric Hematology/Oncology

Disclosure: Nothing to disclose.

Chief Editor

Max J Coppes, MD, PhD, MBA Executive Vice President, Chief Medical and Academic Officer, Renown Heath

Max J Coppes, MD, PhD, MBA is a member of the following medical societies: American College of Healthcare Executives, American Society of Pediatric Hematology/Oncology, Society for Pediatric Research

Disclosure: Nothing to disclose.

Additional Contributors

Sharada A Sarnaik, MBBS Professor of Pediatrics, Wayne State University School of Medicine; Director, Sickle Cell Center, Associate Hematologist/Oncologist, Children's Hospital of Michigan

Sharada A Sarnaik, MBBS is a member of the following medical societies: American Society of Hematology, American Society of Pediatric Hematology/Oncology, New York Academy of Sciences, Society for Pediatric Research, Children's Oncology Group, American Academy of Pediatrics, Midwest Society for Pediatric Research

Disclosure: Nothing to disclose.