Vitamin B12 deficiency neurological syndromes: correlation of clinical, MRI and cognitive evoked potential

Non-Linear Association between Folate/Vitamin B12 Status and Cognitive Function in Older Adults

Although folate and vitamin B12 status have long been implicated in cognitive function, there is no consensus on the threshold of folate and vitamin B12 for assessing their impacts on cognition. The goal of this study was to detail the association between folate and vitamin B12 with cognitive performance. We analyzed cross-sectional data of older adults (≥60 y; n = 2204) from the NHANES (National Health and Nutrition Examination Surveys) cohort from 2011–2014. The restricted cubic spline model was used for describing the associations between serum total folate, RBC folate, 5-methyltetrahydrofolate, and vitamin B12 and the Consortium to Establish a Registry for Alzheimer’s Disease Word Learning (CERAD-WL) and Delayed Recall (CERAD-DR) tests, the Animal Fluency (AF) test, and the Digit Symbol Substitution Test (DSST), respectively. Older adults with a different folate and vitamin B12 status were clustered by artificial intelligence unsupervised learning. The statistically significant non-linear relationships between the markers of folate or vitamin B12 status and cognitive function were found after adjustments for potential confounders. Inverse U-shaped associations between folate/vitamin B12 status and cognitive function were observed, and the estimated breakpoint was described. No statistically significant interaction between vitamin B12 and folate status on cognitive function was observed in the current models. In addition, based on the biochemical examination of these four markers, older adults could be assigned into three clusters representing relatively low, medium, and high folate/vitamin B12 status with significantly different scores on the CERAD-DR and DSST. Low or high folate and vitamin B12 status affected selective domains of cognition, and was associated with suboptimal cognitive test outcomes.

Surgical Approach in Intraocular Tumors

Surgery in intraocular tumors is done for excision/biopsy and the management of complications secondary to the treatment of these tumors. Excision/biopsy of intraocular tumors can be done via fine-needle aspiration biopsy (FNAB), transretinal biopsy (TRB), partial lamellar sclerouvectomy (PLSU), and endoresection. FNAB, TRB, and PLSU can be used in tumors that cannot be diagnosed by clinical examination and other ancillary testing methods. PLSU is employed in tumors involving the iridociliary region and choroid anterior to the equator. Excisional PLSU is performed for iridociliary and ciliary body tumors with less than 3 clock hours of iris and ciliary body involvement and choroidal tumors with a base diameter less than 15 mm. However, for biopsy, PLSU can be employed with any size tumor. Endoresection is a procedure whereby the intraocular tumor is excised using vitrectomy techniques. The rationale for performing endoresection is based on the fact that irradiated uveal melanomas may cause complications such as exudation, neovascular glaucoma, and intraocular pigment and tumor dissemination (toxic tumor syndrome), and removing the dead tumor tissue may contribute to better visual outcome. Endoresection is recommended 1-2 weeks after external radiotherapy. Pars plana vitrectomy is also used in the management of complications including vitreous hemorrhage, retinal detachment, and epiretinal membrane that can occur after treatment of posterior segment tumors using radiotherapy and transpupillary thermotherapy. It is important to make sure the intraocular tumor has been eradicated before embarking on such treatment.

Prognostic indicators of subacute combined degeneration from B12 deficiency: A systematic review

OBJECTIVE

A systematic review was conducted on published data of subacute combined degeneration (SCD) from B12 deficiency to investigate potential prognostic indicators of final ambulatory function in affected patients. TYPE: Systematic review.

LITERATURE SURVEY

Records published from 1999 through 2018 were searched on the electronic databases MEDLINE, PUBMED, and SCOPUS. The publication language was restricted to English and French.

METHODOLOGY

Records that described cases of SCD from B12 deficiency in patients ≥16 years of age at onset were included. From a final total of 66 cases of SCD identified, ambulation scores were assigned based on the clinical descriptions reported. Patient characteristics, clinical manifestations, and ambulatory function were reported descriptively. Subanalyses on potential prognostic indicators were performed.

SYNTHESIS

Greater ambulatory function at diagnosis was associated with recovery of normal ambulatory function at follow-up (P < .001). Nearly 90% of patients walking unsupported at diagnosis made a complete recovery regardless of etiology. For patients initially walking with support, 22% of cases from impaired B12 digestion/absorption made a complete recovery compared with ≥50% of cases from other etiologies. For patients initially requiring a wheelchair, 33% of cases from impaired digestion/absorption were able to walk with support compared with ≥50% of cases from other etiologies. The total B12 administered over the course of treatment was correlated with improved ambulation (P = .024) for all patients, with a higher B12 replacement regimen associated with better outcomes in patients who were unable to walk unsupported at diagnosis (number needed to treat = 4).

CONCLUSIONS

Initial ambulatory function may be a useful clinical marker of the severity of spinal cord dysfunction and final functional outcome. Etiological risk factors influenced both clinical manifestations and final walking ability in SCD, suggesting a distinct pathophysiological mechanism among the causes. In addition, a more intensive B12 replacement regimen may improve ultimate ambulatory function in advanced cases of SCD.

Subacute combined degeneration of the spinal cord in functional vitamin B12 Deficiency states

Vitamin B12 is an essential enzymatic cofactor in multiple cellular metabolic pathways. Deficiency states can arise as a result of both depletion of absolute systemic levels and pathological processes that block its ability to act as an enzymatic cofactor. The latter is also known as functional vitamin B12 deficiency. This can cause a variety of systemic, haematological, and neurological manifestations, some of which may be irreversible if not promptly treated. Neurological syndromes include subacute combined degeneration of the cord (SCDC), peripheral, optic, and autonomic neuropathies, and neuropsychiatric or cognitive deficits. This review presents a case series of vitamin B12 deficiencies leading to SCDC, and we include the clinical features, significant investigations, treatments, and prognoses.

Bilateral Foot-Drop Secondary to Axonal Neuropathy in a Tuberculosis Patient With Co-Infection of COVID-19: A Case Report

Tuberculosis (TB) is a global pandemic and is one of the top 10 causes of death worldwide as well as the leading cause of death from a single infectious agent. It can cause a wide array of complications including peripheral neuropathy. In addition to TB pandemic the recent pandemic of coronavirus disease 2019 (COVID-19) has led to an increased interest in the co-infection of TB patients and COVID-19 and whether TB increases risk for COVID-19 and its role in causing severity of disease and vice-versa. This case report discusses about a young cachectic man who was found to have bilateral foot-drop under the setting of TB with co-infection of COVID-19 later confirmed to be axonal neuropathy on nerve conduction study. The report highlights the importance of differential diagnosis of TB in COVID-19 patients as well as the consideration of TB in a patient with peripheral neuropathy after nutritional causes have been ruled out.

Subacute combined degeneration of the spinal cord masking motor neuron disease: a case report

Background

Subacute combined degeneration of the spinal cord is a potentially reversible myelopathy typically associated with vitamin B12 deficiency. There is predominant involvement of spinal cord posterior and lateral tracts, and manifestations include peripheral paraesthesia, impaired proprioception, gait disturbance, neuropathy and cognitive changes. Motor neuron disease (MND) is an unremittingly progressive neurodegenerative disorder involving upper and lower motor neurons with an average prognosis of 2–3 years. The diagnosis is clinical and may be supported by electromyography. A subset of MND occurs concurrently with frontotemporal dementia (FTD-MND) and may be initially misdiagnosed as a primary psychotic disorder.

Case presentation

We describe a 57-year-old Caucasian woman who presented with confusion and dysarthria. Low vitamin B12 levels and MRI findings led to an initial diagnosis of subacute combined degeneration of the spinal cord. Despite treatment, persistent dysarthria and presence of both upper and lower motor neuron signs on clinical examination prompted further assessment. Electromyography supported the diagnosis of MND. Comorbid chronic paranoid schizophrenia complicated the diagnostic process. We discuss overlapping features between B12 deficiency and MND as well as the neuropsychiatric overlap of B12 deficiency, FTD-MND and chronic schizophrenia.

Conclusions

Firstly, variability in neurocognitive and imaging manifestations of B12 deficiency can limit delineation of other pathologies. Failure to improve following correction of nutritional deficiencies warrants further investigation for an alternate diagnosis. Secondly, re-evaluation of patients with comorbid mental health conditions is important in reaching timely and accurate diagnoses.

Evaluation of optic nerve functions in subacute combined degeneration using visual evoked potential and diffusion tensor imaging-a pilot study

OBJECTIVE:

To evaluate optic nerve involvement in subacute combined degeneration (SACD) using diffusion tensor imaging (DTI) and visual evoked potential (VEP) studies, and their changes following cobalamine treatment.

METHODS:

Six patients with SACD and six healthy matched controls were included. Visual acuity, field of vision, and color vision were tested. Pattern shift VEP was done, and P100 latency and amplitude were measured. Optic nerve MRI, and DTI of optic nerve to muscle ratio were measured, and fractional anisotropy ratio (FAR), axial diffusivity ratio (ADR), radial diffusivity ratio (RDR), and mean diffusivity ratio (MDR) were calculated. The patients received hydroxyl cobalamine 1000 µg intramuscularly and their clinical examination, VEP and DTI studies were repeated at 3 months.

RESULTS:

The age of the patients ranged between 16 and 60 years and two were females. Their visual acuity, field of vision, and color vision were normal. P100 latency was prolonged in five patients (10 eyes) and amplitude was reduced in one (1 eye). The SACD patients had reduced FAR (1.94 ± 0.55 vs 2.81 ± 0.42; p = 0.01) and increased MDR (1.00 ± 0.04 vs 0.95 ± 0.01; p = 0.01) and RDR (0.96 ± 0.03 vs 0.89 ± 0.01; p = 0.002) compared to the controls. The FAR value correlated with P100 latency (r = -0.88). At 3 months, FAR value increased which was associated with improvement in P100 latency.

CONCLUSION:

In SACD patients, optic nerve FAR is reduced and correlates with P100 latency. Both these parameters improve on cobalamine treatment.

ADVANCES IN KNOWLEDGE:

Subclinical VEP abnormalities are common in SACD but conventional MRI sequence of optic nerve is normal. DTI of optic nerve reveals reduced fractional anisotropy (FA) values which improve after cobalamine treatment. FA values correlate with prolongation of P100 latency. DTI and VEP abnormalities suggest subclinical optic nerve myelin dysfunction.

A brief history of meat in the human diet and current health implications

Anthropological investigations have confirmed many times over, through multiple fields of research the critical role of consumption of animal source foods (ASF) including meat in the evolution of our species. As early as four million years ago, our early bipedal hominin ancestors were scavenging ASFs as evidenced by cut marks on animal bone remains, stable isotope composition of these hominin remains and numerous other lines of evidence from physiological and paleo-anthropological domains. This ASF intake marked a transition from a largely forest dwelling frugivorous lifestyle to a more open rangeland existence and resulted in numerous adaptations, including a rapidly increasing brain size and altered gut structure. Details of the various fields of anthropological evidence are discussed, followed by a summary of the health implications of meat consumption in the modern world, including issues around saturated fat and omega-3 fatty acid intake and discussion of the critical nutrients ASFs supply, with particular emphasis on brain function.

Enhanced vitamin B12 production in an innovative lupin tempeh is due to synergic effects of Rhizopus and Propionibacterium in cofermentation

Fermentation represents a valuable and cost-effective approach for food stabilisation and nutritional improvement. Tempeh is an example of soybean solid-state fermentation. In this work, we investigated the possibility of producing a tempeh analogue containing high amounts of vitamin B12 using seeds of three different species of the legume lupin, namely Lupinus albus, L. angustifolius and L. mutabilis, with Rhizopus oligosporus and Propionibacterium freudenreichii cofermentation. Synergic effects of Rhizopus and Propionibacterium in increasing vitamin B12 up to 1230 ng/g dw was observed. These findings indicate that this cofermentation can improve lupin nutritional quality and safety to provide a tempeh analogue with added value for vegan and vegetarian communities and low-income populations. The level of potentially toxic lupin alkaloids was also monitored during the tempeh preparation.

Approach to a case of myeloneuropathy

Myeloneuropathy is a frequently encountered condition and often poses a diagnostic challenge. A variety of nutritional, toxic, metabolic, infective, inflammatory, and paraneoplastic disorders can present with myeloneuropathy. Deficiencies of vitamin B12, folic acid, copper, and vitamin E may lead to myeloneuropathy with a clinical picture of subacute combined degeneration of the spinal cord. Among infective causes, chikungunya virus has been shown to produce a syndrome similar to myeloneuropathy. Vacuolar myelopathy seen in human immunodeficiency virus (HIV) infection is clinically very similar to subacute combined degeneration. A paraneoplastic myeloneuropathy, an immune-mediated disorder associated with an underlying malignancy, may rarely be seen with breast cancer. Tropical myeloneuropathies are classified into two overlapping clinical entities — tropical ataxic neuropathy and tropical spastic paraparesis. Tropical spastic paraparesis, a chronic noncompressive myelopathy, has frequently been reported from South India. Establishing the correct diagnosis of myeloneuropathy is important because compressive myelopathies may pose diagnostic confusion. Magnetic resonance imaging (MRI) in subacute combined degeneration of the spinal cord typically reveals characteristic signal changes on T2-weighted images of the cervical spinal cord. Once the presence of myeloneuropathy is established, all these patients should be subjected to a battery of tests. Blood levels of vitamin B12, folic acid, vitamins A, D, E, and K, along with levels of iron, methylmalonic acid, homocysteine, and calcium should be assessed. The pattern of neurologic involvement and results obtained from a battery of biochemical tests often help in establishing the correct diagnosis.

Myanmarese Neuropathy: Clinical Description of Acute Peripheral Neuropathy Detected among Myanmarese Refugees in Malaysia

Background. Since 2008, we have observed an increasing number of Myanmarese refugees in Malaysia being admitted for acute/subacute onset peripheral neuropathy. Most of them had a preceding history of starvation. Methods. We retrospectively studied the clinical features of all Myanmarese patients admitted with peripheral neuropathy from September 2008 to January 2014. Results. A total of 24 patients from the Chin, Rohingya, and Rakhine ethnicities (mean age, 23.8 years; male, 96%) had symmetrical, ascending areflexic weakness with at least one additional presenting symptom of fever, lower limb swelling, vomiting, abdominal pain, or difficulty in breathing. Twenty (83.3%) had sensory symptoms. Ten (41.6%) had cranial nerve involvement. Nineteen patients had cerebrospinal fluid examinations but none with evidence of albuminocytological dissociation. Neurophysiological assessment revealed axonal polyneuropathy, predominantly a motor-sensory subtype. Folate and vitamin B12 deficiencies were detected in 31.5% of them. These findings suggested the presence of a polyneuropathy related to nutrition against a backdrop of other possible environmental factors such as infections, metabolic disorders, or exposure to unknown toxin. Supportive treatment with appropriate vitamins supplementation improved functional outcome in most patients. Conclusion. We report a spectrum of acquired reversible neurological manifestations among Myanmarese refugees likely to be multifactorial with micronutrient deficiencies playing an important role in the pathogenesis.

Clinical, nerve conduction and nerve biopsy study in vitamin B12 deficiency neurological syndrome with a short-term follow-up

OBJECTIVE

The frequency and type of neuropathy in vitamin B12 deficiency neurological syndrome (VBDNS) is controversial. This study reports the frequency and type of nerve dysfunction in VBDNS using nerve conduction and sural nerve biopsy and its response to treatment.

METHOD

Sixty-six patients with VBDNS diagnosed on the basis of low serum vitamin B12 level and/or megaloblastic bone marrow were subjected to clinical evaluation, hemoglobin, mean corpuscular volume, thyroid function test, HIV serology, and vasculitic profile. Peroneal motor and sural sensory nerve conduction studies were done. Sural nerve biopsy was done in six patients. The patients were treated with cyanocobalamin injection and followed up clinically and with nerve conduction study at 3 and 6 months.

RESULTS

The median age of the patients was 46 (12-80) years and 11 patients were females. The duration of symptoms was 1-96 (median 7) months. Clinical features of neuropathy were present in 46 (69.7%) patients and nerve conduction was abnormal in 36 (54.5%) patients. On nerve conduction study, 8 (22.2%) patients had axonal, 4 (11.1%) had demyelinating, and 24 (66.7%) had mixed features. Nerve biopsy revealed acute axonal degeneration in early stage and chronic axonopathy with demyelination in the late stages of disease. The nerve conduction parameters improved at 6 months along with clinical recovery.

CONCLUSION

Nearly 70% patients with VBDNS had evidence of neuropathy which is mainly axonal with some demyelinating features.

Serum folate but not vitamin B-12 concentrations are positively associated with cognitive test scores in children aged 6-16 years

Folate and vitamin B-12 are important for nervous system functioning at all ages, with important roles in functions such as neurotransmitter synthesis. Although studies suggest a relation between folate and vitamin B-12 and cognitive function in the elderly population, there is relatively less evidence regarding these vitamins and children's cognitive function. The purpose of the study was to examine the associations of serum folate and vitamin B-12 with cognitive performance in children 6-16 y old in the NHANES III, conducted from 1988 to 1994, prior to the implementation of folic acid fortification. A cross-sectional analysis was conducted using data on 5365 children 6-16 y old from NHANES III. Serum folate and vitamin B-12 concentrations were measured, along with performance, on the Wide Range Achievement Test-Revised and the Wechsler Intelligence Scale for Children-Revised. Associations of B vitamins with cognitive performance were assessed using linear regression models adjusted for various covariates. Higher serum concentrations of folate were associated with higher reading and block design scores after adjusting for various covariates. For example, compared with the lowest quartile of folate, children in the highest quartile scored 3.28 points or 0.19 SD units higher on the reading test (P < 0.05). Vitamin B-12 was not associated with any of the test scores. In the largest study to date, higher folate concentrations were associated with better reading and block design scores. These associations appear to be biologically plausible and merit further study.

Cognitive impairment and vitamin B12: a review

BACKGROUND

This review examines the associations between low vitamin B12 levels, neurodegenerative disease, and cognitive impairment. The potential impact of comorbidities and medications associated with vitamin B12 derangements were also investigated. In addition, we reviewed the evidence as to whether vitamin B12 therapy is efficacious for cognitive impairment and dementia.

METHODS

A systematic literature search identified 43 studies investigating the association of vitamin B12 and cognitive impairment or dementia. Seventeen studies reported on the efficacy of vitamin B12 therapy for these conditions.

RESULTS

Vitamin B12 levels in the subclinical low-normal range (<250 ρmol/L) are associated with Alzheimer's disease, vascular dementia, and Parkinson's disease. Vegetarianism and metformin use contribute to depressed vitamin B12 levels and may independently increase the risk for cognitive impairment. Vitamin B12 deficiency (<150 ρmol/L) is associated with cognitive impairment. Vitamin B12 supplements administered orally or parenterally at high dose (1 mg daily) were effective in correcting biochemical deficiency, but improved cognition only in patients with pre-existing vitamin B12 deficiency (serum vitamin B12 levels <150 ρmol/L or serum homocysteine levels >19.9 μmol/L).

CONCLUSION

Low serum vitamin B12 levels are associated with neurodegenerative disease and cognitive impairment. There is a small subset of dementias that are reversible with vitamin B12 therapy and this treatment is inexpensive and safe. Vitamin B12 therapy does not improve cognition in patients without pre-existing deficiency. There is a need for large, well-resourced clinical trials to close the gaps in our current understanding of the nature of the associations of vitamin B12 insufficiency and neurodegenerative disease.

Leukoencephalopathies and leukodystrophies

The leukoencephalopathies encompass a heterogeneous group of disorders that involve the brain white matter. The cause may be acquired or inherited; in the latter case, mutations have been found in genes that encode protein components of the myelin membrane or enzymes implicated in the turnover of myelin. In patients with cognitive dysfunction and white matter lesions evident on MRI, analysis of the type, pattern, and distribution of lesions can enable a presumptive diagnosis, which can be confirmed by biochemical and/or molecular testing. The presence or absence of peripheral neuropathy and/or autonomic dysfunction can be a helpful clue in differentiating individual diagnoses. Often, patients may be suspected of having and being initially treated inappropriately for a case of primary or secondary progressive multiple sclerosis. In a significant number of patients, the diagnosis may not be made, even after an extensive search. Establishing the cause enables counseling regarding prognosis, family planning, monitoring for disease-related complications, and introducing therapy, when available.

[Diagnosis of vitamin B12 deficiency: a case illustrating diagnostic pitfalls]

INTRODUCTION

Vitamin B12 deficiency is a longstanding public health problem which affects more than 20% of the elderly population. Among multiple causes of vitamin B12 deficiency, Biermer's disease is currently mentioned in about 25% of the cases.

OBSERVATION

We report the case of a 71-year-old woman, taking folate substitution therapy who, over 2 years, progressively developed spinal combined sclerosis, subacute dementia and severe neuropathy leading to a bedridden state. The initial assessment revealed normocytic anemia, without vitamin B12 deficiency and without increased plasma level of biological markers. The plasma folate level was high. Vitamin B12 assay was repeated leading to the diagnosis of deficiency associated with the presence of intrinsic factor antibodies.

DISCUSSION

This observation illustrates the broad spectrum of clinical presentations of vitamin B12 deficiency. In the present case, the lack of sensitivity of biological markers delayed diagnosis and had a dramatic impact on outcome. This case highlights the importance of promoting factors such as isolated folate substitution in B12 deficient patients.

Relationship of homocysteine with other risk factors and outcome of ischemic stroke

OBJECTIVE

Hyperhomocysteinemia (HH) is an emerging risk factor for ischemic stroke but its role in outcome is controversial. We compare the risk factors, nature of stroke and outcome of patients with and without hyperhomocysteinemia.

PATIENTS AND METHODS

CT proven ischemic stroke patients were included. The conventional risk factors such as diabetes, hypertension, hyperlipidemia, obesity, smoking, and family history of stroke were recorded. Dietary history was noted. Fasting serum homocysteine (Hcy), B12 and folic acid were estimated after 1 month of stroke. Severity of stroke was assessed by Canadian Neurological Scale (CNS) and outcome at 3 months by Barthel Index (BI) score into good (BI > or = 12) and poor (BI < 12). Serum Hcy, B12 and folic acid were also estimated in 200 normal healthy volunteers.

RESULTS

There were 198 patients with ischemic stroke whose median age was 56 years and 36 were females. In the study group, 41.4% patients were vegetarian, 55.1% hypertensive, 24.7% diabetic, 30.8% smoker, 61.1% sedentary and 28.8% obese. 23.2% had past history of stroke and 21.7% had stroke in their first degree relative. Serum cholesterol was elevated in 11.7% and LDL in 10.8% patients. Serum Hcy was elevated in 60.6% and serum B12 low in 25.7% and folic acid in 42.1%. Hcy levels correlated with serum B12 and LDL. Patients with hyperhomocysteinemia had significantly better outcome at 3 months. Hcy levels in stroke patients did not significantly differ from controls.

CONCLUSION

Hyperhomocysteinemia is found in 60.6% stroke patients, which is related to low serum B12 level. Patients with hyperhomocysteinemia had a better 3-month outcome.