intrinsic-factor and Cognition-Disorders

Leukoencephalopathy and autonomic dysfunction have been described in individuals with very low serum B(12) levels (<200 pg/ml), in addition to psychiatric changes, neuropathy, dementia and subacute combined degeneration. Elevated homocysteine and methylmalonic acid levels are considered more sensitive and specific for evaluating truly functional B(12) deficiency. A previously healthy 62-year-old woman developed depression and cognitive deficits with autonomic dysfunction that progressed over the course of 5 years. The patient had progressive, severe leukoencephalopathy on multiple MRI scans over 5 years. Serum B(12) levels ranged from 267 to 447 pg/ml. Homocysteine and methylmalonic acid levels were normal. Testing for antibody to intrinsic factor was positive, consistent with pernicious anaemia. After treatment with intramuscular B(12) injections (1000 μg daily for 1 week, weekly for 6 weeks, then monthly), she made a remarkable clinical recovery but remained amnesic for major events of the last 5 years. Repeat MRI showed partial resolution of white matter changes. Serum B(12), homocysteine and methylmalonic acid levels are unreliable predictors of B(12)-responsive neurologic disorders, and should be thoroughly investigated and presumptively treated in patients with unexplained leukoencephalopathy because even long-standing deficits may be reversible.

Topics: Autoantibodies; Autonomic Nervous System Diseases; Brain; Cognition Disorders; Depressive Disorder; Drug Therapy, Combination; Female; Homocysteine; Humans; Intrinsic Factor; Leukoencephalopathies; Magnetic Resonance Imaging; Mental Status Schedule; Methylmalonic Acid; Middle Aged; Neurologic Examination; Psychometrics; Vitamin B 12; Vitamin B 12 Deficiency; Vitamin D

A Johns Hopkins University study reveals that HIV-infected men with abnormally low B vitamin blood levels progressed to AIDS twice as fast as those with normal levels. Low levels of B12 have also been found in persons with Chronic Fatigue Immune Dysfunction Syndrome (CFID). Since both ailments have a common virus in HHV-6A, the virus is suspected, although unproven, of causing the inability of the intestines to absorb B12 by affecting intrinsic factor levels.

Topics: Acquired Immunodeficiency Syndrome; Cognition Disorders; Fatigue Syndrome, Chronic; Herpesvirus 6, Human; Humans; Intrinsic Factor; Vitamin B 12; Vitamin B 12 Deficiency

Topics: Affective Symptoms; Aged; Anemia, Pernicious; Antibodies; Cognition Disorders; Dementia; Female; Folic Acid Deficiency; Gastric Mucosa; Humans; Intracranial Arteriosclerosis; Intrinsic Factor; Male; Mental Disorders; Schilling Test; Vitamin B 12 Deficiency