Further Outpatient Care

Patients with neurologic impairment may require additional care in skilled nursing units or rehabilitation facilities. Outpatient follow-up is required to ensure response to therapy.

Further Inpatient Care

Once therapy is initiated, hospitalization is only required for patients with life-threatening anemia or with severe neurologic deficits requiring supervision or rehabilitation.

Inpatient & Outpatient Medications

See the list below:

Cobalamin 100-1000 mcg/mo SC/IM, 1000 mcg/d PO is provided for lifelong maintenance.
Compliance must be verified to avoid recurrence of symptoms.

Deterrence/Prevention

See the list below:

Relatives of patients with PA must be made aware of the increased familial incidence.
Individuals with total gastrectomy, pancreatectomy, or atrophic gastritis should undergo periodic testing for vitamin B-12 deficiency.
Testing vitamin B-12 (and folate) levels in elderly patients is good practice because of the high incidence of deficiencies. Asymptomatic deficiency should be worked up and treated.
Strict vegetarians should supplement vitamin B-12 in their diets.

Complications

See the list below:

If left untreated, neurologic complications worsen.
Severe anemia may lead to congestive heart failure.
Incidence of atrophic gastritis, gastric carcinoma, and carcinoid tumors is increased in patients with PA.
Patients with PA are at increased risk for other autoimmune disorders, such as myasthenia gravis, Lambert-Eaton myasthenic syndrome, type 1 diabetes mellitus, Hashimoto thyroiditis, hypogammaglobulinemia, vitiligo, and rheumatoid arthritis.^[28]
Risk of neural tube defects is increased in untreated pregnant women.

Prognosis

See the list below:

Therapy with vitamin B-12 in subacute combined degeneration stops progression and improves neurologic deficit in most patients.
Younger patients with less severe disease and short duration illness do better.
In a large retrospective review of 57 patients with subacute combined degeneration, absence of sensory level, absent Rhomberg sign, and flexor planter reflex were associated with good prognosis.^[29]
On spinal MRI, involvement of less than 7 spinal segments, cord swelling, and enhancement, but not cord atrophy, were associated with better prognosis.^[29]
Clinical improvement is most pronounced in the first 2 months but continues up to 6 months.

Questions

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Media Gallery

Vitamin B-12–associated neurological diseases. Cobalamin and folate metabolism. TS = thymidylate synthase, DHFR = dihydrofolate reductase, SHMT = serine methyl-transferase.
Vitamin B-12–associated neurological diseases. Cobalamin deficiency leads to reduced adenosylcobalamin, which is required for production of succinyl-CoA. D-methylmalonyl-CoA is converted to methylmalonic acid.
Vitamin B-12–associated neurological diseases. Pernicious anemia. Characteristic lemon-yellow pallor with raw beef tongue lacking filiform papillae. Photo from Forbes and Jackson with permission.
Vitamin B-12–associated neurological diseases. Fluid attenuated inversion recovery (Flair) MRI sequence in a patient with cobalamin deficiency and neuropsychiatric manifestations. Discrete areas of hyperintensities are present in the corona radiata.

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Author

Niranjan N Singh, MBBS, MD, DM, FAHS, FAANEM Adjunct Associate Professor of Neurology, University of Missouri-Columbia School of Medicine; Medical Director of St Mary's Stroke Program, SSM Neurosciences Institute, SSM Health

Niranjan N Singh, MBBS, MD, DM, FAHS, FAANEM is a member of the following medical societies: American Academy of Neurology, American Association of Neuromuscular and Electrodiagnostic Medicine, American Headache Society

Disclosure: Nothing to disclose.

Coauthor(s)

Florian P Thomas, MD, PhD, MA, MS Chair, Neuroscience Institute and Department of Neurology, Director, Hereditary Neuropathy Center, Co-Director, Center for Memory Loss and Brain Health, Co-Director, ALS Center, Hackensack University Medical Center; Associate Dean of Faculty, Founding Chair and Professor, Department of Neurology, Hackensack Meridian School of Medicine

Florian P Thomas, MD, PhD, MA, MS is a member of the following medical societies: Academy of Spinal Cord Injury Professionals, American Academy of Neurology, American Neurological Association, Consortium of Multiple Sclerosis Centers, National Multiple Sclerosis Society, Sigma Xi, The Scientific Research Honor Society

Disclosure: Nothing to disclose.

Alan L Diamond, DO Movement Disorder Fellow, Department of Neurology, Baylor College of Medicine

Alan L Diamond, DO is a member of the following medical societies: American Academy of Neurology, American Medical Association, American Osteopathic Association, American Society of Neuroimaging

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Nestor Galvez-Jimenez, MD, MSc, MHA The Pauline M Braathen Endowed Chair in Neurology, Chairman, Department of Neurology, Program Director, Movement Disorders, Department of Neurology, Division of Medicine, Cleveland Clinic Florida

Nestor Galvez-Jimenez, MD, MSc, MHA is a member of the following medical societies: American Academy of Neurology, American College of Physicians, International Parkinson and Movement Disorder Society

Disclosure: Nothing to disclose.

Chief Editor

Selim R Benbadis, MD Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, Tampa General Hospital, University of South Florida Morsani College of Medicine

Selim R Benbadis, MD is a member of the following medical societies: American Academy of Neurology, American Academy of Sleep Medicine, American Clinical Neurophysiology Society, American Epilepsy Society, American Medical Association

Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: Bioserenity, Ceribell, Eisai, Jazz, LivaNova, Neurelis, Neuropace, SK life science, Sunovion, Takeda, UCB<br/>Serve(d) as a speaker or a member of a speakers bureau for: Aquestive, Bioserenity, Eisai, Jazz, LivaNova, Neurelis, SK life science, Stratus, Sunovion, UCB<br/>Received research grant from: Cerevel Therapeutics, Ovid Therapeutics, Neuropace, Greenwich Jazz, SK Life Science, Xenon Pharmaceuticals, UCB, Marinus, Neuroelectrics Corporation, Longboard, Janssen, Equilibre Biopharmaceuticals.

Additional Contributors

Christopher Luzzio, MD Clinical Assistant Professor, Department of Neurology, University of Wisconsin at Madison School of Medicine and Public Health

Christopher Luzzio, MD is a member of the following medical societies: American Academy of Neurology

Disclosure: Nothing to disclose.