CME Tutorial on Detection of B12 Deficiency in Clinical Settings
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Why Vitamin B Deficiency Should Be 12on Your Radar Screen A Continuing Education Update Course WB1349 Prepared for the National Center on Birth Defects and Developmental Disabilities Centers for Disease Control and Prevention by 1 Marian L. Evatt, MD2Patricia W. Mersereau, MN, CPNP 3 Janet Kay Bobo, PhD4 Joel Kimmons, PhD5 Jennifer Williams, MSN, MPH, FNP-BC The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention. 1 Department of Neurology, Emory University, Atlanta, Georgia. 2SciMetrika, LLC, Atlanta, Georgia. 3 Battelle Centers for Public Health Research and Evaluation, Atlanta, GA and Seattle, Washington. 4 National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, Georgia. 5National Center on Birth Defects and Developmental Disabilities, CDC, Atlanta, Georgia. iVitamin B Deficiency 12 Contents Goal and Objectives .................................................................................1 Accreditation ...........................................................................................2 Introduction ............................................................................................3 Case Studies6 Deficiency......................14 Natural History and Prevalence of Vitamin B12Risk Factors for Vitamin B Deficiency.................. ...
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Why Vitamin B12Deficiency Should Be on Your Radar Screen A Continuing Education Update CourseWB1349Prepared for the National Center on Birth Defects and Developmental Disabilities Centers for Disease Control and Prevention by Marian L. Evatt, MD1 Patricia W. Mersereau, MN, CPNP2Janet Kay Bobo, PhD3 Joel Kimmons, PhD4 Jennifer Williams, MSN, MPH, FNP-BC5 The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
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1Department of Neurology, Emory University, Atlanta, Georgia. 2SciMetrika, LLC, Atlanta, Georgia. 3Battelle Centers for Public Health Research and Evaluation, Atlanta, GA and Seattle, Washington. 4National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, Georgia. 5National Center on Birth Defects and Developmental Disabilities, CDC, Atlanta, Georgia.
Contents
Vitamin B12Deficiency
GoalandObjectives.................................................................................1 Accreditation...........................................................................................2 Introduction............................................................................................3 CaseStudies............................................................................................6 Natural History and Prevalence of Vitamin B12Deficiency...................... 14 Risk Factors for Vitamin B12Deficiency .................................................. 20 Manifestations of Low Vitamin B12 23Levels .............................................. Screening Patients ................................................................................. 27 DetectionandDiagnosis........................................................................28 Managing Patients With Evidence of a Vitamin B12Deficiency................ 35 Prevention of Vitamin B12Deficiencies ................................................... 40 Summary...............................................................................................42 References ............................................................................................. 43 ReferencesforTextinBoxes.................................................................49Appendix A: Answers to Case Study Questions ...................................... 51 Appendix B: Additional Articles on Vitamin B12 53Deficiency ..................... Appendix C: Evaluation Questionnaire, Pretest, and Posttest ................ 56
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Figure and Tables Figure 1. The Biochemical Role of Cobalamin ........................................ 16 Table 1. Neurologic and Psychiatric Symptoms of Vitamin B12Deficiency and Parkinson Disease (PD) ................................... 13 Table 2.Typical Stages in the Development of a Vitamin B12Deficiency .............................................................. 17Table 3. Prevalence of Vitamin B12Serum Levels for the U.S. Population By Age, National Health and Nutrition Examination Survey 20012004 19 Table 4. Prevalence of National Health and Nutrition Examination Survey Participants With Biochemically Defined Vitamin B12Deficiency * By Age Group, United States, 20012004 31 Table 5. Tailored Diagnostic Approach for Vitamin B1234yienccifeDTable 6. Examples of Treatment Regimens for Vitamin B12Deficiency38Disclosure CDC, planners, and other content experts wish to disclose they have no financial interests or other relationships with the manufacturers of commercial products, suppliers of commercial services, or commercial supporters. This module will not include any discussions of the unlabeled use of a product or a product under investigational use.
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Why Vitamin B12Deficiency Should Be on Your Radar Screen: A Continuing Education Update Goal and Objectives The goal of this continuing education activity is to increase the number of primary care providers (physicians and midlevel providers) who prevent, detect, and treat vitamin B12deficiencies among their high-risk patients. After completing this continuing education material, you should be able to • Describe the prevalence in the United States of vitamin B12deficiency among adults 51 years of age or older. • List three neurologic effects of a vitamin B12deficiency. • List three hematologic effects of a vitamin B12deficiency. • Identify the most common presentation of a vitamin B12deficiency. • Discuss the changes in absorption of vitamin B12that occur with age. • List at least two pharmacologic options for treatment of a vitamin B12deficiency.
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Accreditation
Continuing Medical Education (CME):This activity for 1.5 credits is provided by the Centers for Disease Control and Prevention (CDC), accredited by the Accreditation Council for Continuing Medical Education to provide category 1 credits towards the American Medical Association (AMA) Physicians Recognition Award. Continuing Nursing Education (CNE):This activity for 1.5 contact hours is provided by CDC, which is accredited as a provider of continuing education in nursing by the American Nurses Credentialing Centers Commission on Accreditation (ANCC).
Registration
To register for the course and receive free continuing education credit: Go tohttp://www.cdc.gov/tceonline.. Log in as a participant (note: the first time you use the online system you will need to log in as a new participant and create a participant profile). Find the course by searching the catalog using the following course number:WB1349. You will need to enter the verification code (B12) to complete the course. Select the type of credit you wish to receive and register for the course. Take the examination and complete the course evaluation. Print your continuing education certificate.
To receive continuing education credit, you must complete the entire course, take the post-test, and complete the evaluation online.
During this lesson, you will find highlighted terms. Roll your mouse over each term for further information.
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IntroductionVitamin B12(cobalamin) deficiency should be on your radar screen for several reasons. Prevention, early detection, and treatment of vitamin B deficiency are important public health issues, because they are essential to prevent development of irreversible neurologic damage which can impact quality of life. Although most health care providers already recognize the occasional person who presents with obvious signs and symptoms, they are far less likely to screen and diagnose the majority of patients who have a subclinical or mildly symptomatic vitamin B12deficiency. Vitamin B12deficiency is more common among older adults than many health care providers realize. Unpublished analysis at the Centers for Disease Control and Prevention (CDC) of laboratory data from community-based samples of U.S. adults 51 years of age or older suggest about 1 (3.2%) of every 31 persons have serum vitamin B12levels below 200 picograms per milliliter (pg/mL). Vitamin B12has profound effects on human health. Adequate body stores are essential for several crucial neurologic and hematologic functions. Delays in the diagnosis and treatment of vitamin B12deficiencies can lead to development of severe, irreversible neurologic damage. The clinical importance of vitamin B12was established over 50 years ago, when ingesting raw animal liver (the primary storage organ for vitamin B12) was found to be an effective treatment for pernicious anemia. Research has shown that the water-soluble vitamin B12is required for the completion of several biochemical processes (see Figure 1). The following five top things to remember about vitamin B12in primary care practice summarize the implications of these and other cobalamin-related findings.
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The top five things to remember about vitamin B121. Vitamin B12deficiencies occur in adults 51 years of age or older at a frequency of 1 (3.2%) in every 31 persons, and manifest as serum vitamin B12levels below the cutpoint of 200 picograms per milliliter. 2. All patients with unexplained hematologic or neurologic signs or symptoms should be evaluated for a vitamin B12deficiency. If found, the cause should should be determined. 3. Today, megaloblastic anemia is most likely due to vitamin B12deficiency and needs prompt evaluation. In the United States, folic acid fortification has made folate deficient megaloblastic anemia a very rare condition. 4. Although the bodys ability to absorb naturally occurring vitamin B12decreases with age, most people can readily use the synthetic form of cobalamin. 5. 51 years of age or older should get most ofAll people their daily vitamin B12through supplements containing vitamin B12or foods fortified with vitamin B12.
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This update has been prepared and organized to address four questions pertinent to primary health care providers: Why should I be concerned about my patients vitamin B12status? o ucodtrInonti o Case studies o Natural history and prevalence of vitamin B12deficiencieso Manifestations of low vitamin B12levels Which of my patients are at high risk for vitamin B12deficiency? o Risk factors for a vitamin B12deficiency How do I detect and diagnose a vitamin B12deficiency? o Screening patients o Detection and diagnosis How should I manage a patient with evidence of vitamin B12deficiency? o Managing patients with evidence of a vitamin B12deficiency o Preventing vitamin B12decifiicnese
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Case Studies The following case studies are not actual patients. They combine elements from different cases to emphasize important aspects of vitamin B12deficiency. Case Study 1 PresentationDuring a checkup for hypertension, a 65-year-old female reports a 2-month history of tiredness, feeling faint from getting up too fast, and memory problems. Case Stud uestion 1 Do an of the resentin com laints raise our index of suspicion about a possible vitamin B12 so,deficiency? If why? History On review of systems, she reports difficulty concentrating, fatigue, feeling faint when she stands quickly, and vague gastrointestinal discomfort with some decrease in appetite. She denies any history of previous trauma, diplopia, dysphagia, vertigo, vision loss, loss of consciousness, back pain, or symptoms of bowel or bladder dysfunction. Her family history is negative for neurologic, psychiatric, and autoimmune diseases. Her medications include an antihypertensive, as well as an occasional anti-inflammatory drug for episodic headaches. Her social history reveals a single woman who smokes about one-half pack of cigarettes per day, drinks alcohol only socially, and denies illicit drug use. She has a high school education and, until recently, had worked in the office of a trucking company.
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Case Study Question 2 What risk factors does this woman appear to have for a vitamin B12deficiency?Physical Examination Pale 65 y.o. WF who appears well-nourished, alert, and oriented. Vital Signs T-98.6, HR-76, R-18, B/P-130/80 supine and 95/52 upon standing, Height/Weight 54/120 lbs. Head Normocephalic; oropharynx clear but pale; palpebral conjunctivae pale. Neck Supple, full active and passive ROM without pain, without audible bruits; no lymphadenopathy; no thyromegaly Back No spine tenderness Lungs Clear to auscultation Heart Regular rate and rhythm; no murmurs Abdomen Soft, nontender; no organomegaly Rectal Normal rectal tone; no fissures Extremities No clubbing, cyanosis, or edema; FROM Skin Pale; no rash The general physical examination is unremarkable except for orthostatic hypotension and a weight loss of 3 pounds since her last visit 6 months ago. She is alert and oriented times three. Her Mini-Mental Status Exam score is 26 out of 30. She misses one point on serial 7s and is able to recall three of three items. There is evidence of bilateral mildly diminished vibration and proprioception. Her reflexes are 3+/4+ throughout, with negative Babinski reflex. Cranial IIVisual acuity 20/25 in both eyes Nerves (corrected); normal fundoscopic examination; visual fields intact with no central scotoma III, IV, VIExtraocular movements intact; pupils equal, round, and reactive to light with no afferent pupillary defect V, VII, XIIIntact facial sensation; intact
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masseter motor strength, without dysarthria; tongue protruded in midline VIIIHearing grossly normal XI, XSwallowing intact XIMuscle strength equal bilaterally Motor Normal muscle bulk; muscle strength 5/5 in all muscle groups Cerebellar Normal finger-to-nose, heel-to-shin, and rapid alternating movements
Case Study Questions 3. Does the fact that she appears to be well-nourished indicate she is unlikely to have a vitamin deficiency? Why or why not? 4. Are there any aspects of her physical examination that suggest a vitamin B12deficiency? 5. Given her history and physical examination findings, what laboratory test(s) would you order?
Laboratory Studies You order routine laboratory studies, which include complete blood count (CBC) with smear and chemistry screen. In addition, you order a serum vitamin B12level to investigate further the etiology of her fatigue and pale mucosa. Results from the CBC and smear reveal a borderlinemacrocytic anemia. The chemistry panel is within normal limits. The serum vitamin B12level you requested is 215 picograms per milliliter (pg/mL). This level is considered within a normal range by some laboratories, but you take into account her other signs and symptoms and request confirmatory testing with
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