Optic neuropathy as a presenting feature of vitamin B-12 deficiency: A systematic review of literature and a case report

Associations of circulating vitamins with 10-year retinal neurodegeneration: the Alienor Study

OBJECTIVE

To investigate the associations between circulating vitamins A, D, E, B6, B9, B12 and longitudinal changes in retinal nerve fiber layer (RNFL) thickness.

METHODS

The Alienor study, a prospective population-based cohort (Bordeaux, France), includes 963 individuals aged 73 years or older at baseline. The present study included 646 participants with complete RNFL measurement and vitamins. Study period is from 2009 to 2020. Peripapillary RNFL thickness was measured using spectral domain optical coherence tomography (SD-OCT). Plasma vitamins A, D and E and, serum vitamins B6, B9 and B12 were measured from blood sample. We performed linear mixed models, adjusted for age, gender, axial length, family history of glaucoma, and alcohol consumption to evaluated associations between vitamins and RNFL thickness changes over time.

RESULTS

Individuals having higher concentrations of vitamin E, D and B9 had a slower RNFL thinning during the 10-years of follow-up. Indeed, a 1-standard deviation (SD) increase of vitamin E (10.8 μmol/L), D (17.6 nmol/L) and B9 (11 μmol/L) were associated with slower RNFL thinning by 0.14 μm/year (95% confidence interval (CI), 0.03-0.25, p = 0.01), 0.14 μm/year (95% CI, 0.02-0.27, p = 0.02) and 0.11 μm/year (95% CI: 0.007-0.21, p = 0.04), respectively. No significant associations were observed for vitamins A, B6 and B12 with RNFL thinning.

CONCLUSIONS

Higher levels of vitamins E, D and B9 were associated with a slower RNFL thickness on SD-OCT over time, suggesting that those vitamins may contribute to the neuroprotection of the retina.

Vision Loss as a Presenting Symptom of Vitamin B12 Deficiency

Nutritional optic neuropathy is a rare and often overlooked factor leading to bilateral, symmetrical, and gradual visual impairment. This condition falls within the category of metabolic neuropathies. We documented a case involving bilateral nutritional optic neuropathy attributed to pancytopenia associated with vitamin B12 deficiency. A healthy 65-year-old Indian woman reported a bilateral, progressive, painless decline in vision over the past six months. She had a history of reduced oral intake for the preceding year and denied experiencing any gastrointestinal or constitutional symptoms. Bilateral visual acuity was 1/60. Examination revealed pale optic discs with attenuated vessels in both eyes and a cup-disc ratio of 0.3. The blood analysis showed low indices and a deficiency in serum vitamin B12. Despite undergoing treatment, her vision remained impaired due to the chronic nature of the condition. This case highlights the importance of identifying visual symptoms in an elderly woman experiencing malnutrition caused by inadequate dietary habits, which leads to bilateral nutritional optic neuropathy.

Epigenetics, Nutrition, and the Brain: Improving Mental Health through Diet

The relationship between nutrition and brain health is intricate. Studies suggest that nutrients during early life impact not only human physiology but also mental health. Although the exact molecular mechanisms that depict this relationship remain unclear, there are indications that environmental factors such as eating, lifestyle habits, stress, and physical activity, influence our genes and modulate their function by epigenetic mechanisms to shape mental health outcomes. Epigenetic mechanisms act as crucial link between genes and environmental influences, proving that non-genetic factors could have enduring effects on the epigenome and influence health trajectories. We review studies that demonstrated an epigenetic mechanism of action of nutrition on mental health, focusing on the role of specific micronutrients during critical stages of brain development. The methyl-donor micronutrients of the one-carbon metabolism, such as choline, betaine, methionine, folic acid, VitB6 and VitB12 play critical roles in various physiological processes, including DNA and histone methylation. These micronutrients have been shown to alter gene function and susceptibility to diseases including mental health and metabolic disorders. Understanding how micronutrients influence metabolic genes in humans can lead to the implementation of early nutritional interventions to reduce the risk of developing metabolic and mental health disorders later in life.

Vitamin B12 deficiency presenting as progressive blindness in a 33-year-old HIV-positive female patient on Efavirenz-based regimen: case report

Optic neuritis is a rare presentation of vitamin B12 deficiency. We describe a 33-year-old female patient living with HIV presenting with progressive loss of vision for 1 week. She had a history of severe peripheral neuropathy that was managed with vitamin B12-containing tablets approximately three years before presenting with progressive loss of vision. On examination, she had no perception of light in the left eye and no perception of hand motion in the right eye. The fundus in her left eye had mild blurring of disc margins. Results from tests done showed a haemoglobin of 12.9g/dl, MCV 101fl, a serum vitamin B12 of 78pmol/l, and cytomegalovirus (CMV) test showed no active disease. She was diagnosed with optic neuritis and started on 30 mg tablets of prednisolone for 1 week with slight improvement. She was then started on vitamin B12 injections 1 mg daily for 10 days and thereafter, monthly for 6 months. She reported gradual improvement and regained her sight after 5 months treatment of with Vitamin B12 injections. Ophthalmic manifestations of vitamin B12 deficiency are not common and may present without haematological signs therefore, a high index of suspicion is required for early diagnosis and management of vitamin B12 deficiency.

Metabolic and Toxic Myelopathies

OBJECTIVE

This article reviews the clinical presentation, diagnostic evaluation, and treatment of metabolic and toxic myelopathies resulting from nutritional deficiencies, environmental and dietary toxins, drugs of abuse, systemic medical illnesses, and oncologic treatments.

LATEST DEVELOPMENTS

Increased use of bariatric surgery for obesity has led to higher incidences of deficiencies in nutrients such as vitamin B12 and copper, which can cause subacute combined degeneration. Myelopathies secondary to dietary toxins including konzo and lathyrism are likely to become more prevalent in the setting of climate change leading to drought and flooding. Although modern advances in radiation therapy techniques have reduced the incidence of radiation myelopathy, patients with cancer are living longer due to improved treatments and may require reirradiation that can increase the risk of this condition. Immune checkpoint inhibitors are increasingly used for the treatment of cancer and are associated with a wide variety of immune-mediated neurologic syndromes including myelitis.

ESSENTIAL POINTS

Metabolic and toxic causes should be considered in the diagnosis of myelopathy in patients with particular clinical syndromes, risk factors, and neuroimaging findings. Some of these conditions may be reversible if identified and treated early, requiring careful history, examination, and laboratory and radiologic evaluation for prompt diagnosis.

Serum levels of heavy metals in patients with Bell's palsy: a case-control study

PURPOSE

The exact etiology of Bell's palsy (BP) remains unknown, while its potential etiopathology includes neuritis and inflammation-related demyelination as in optic neuritis. It has been reported that disruption of heavy metal homeostasis may be associated with the inflammatory process of optic neuritis; therefore, heavy metals may be involved in the pathogenesis of facial nerve neuritis. In this study, we aimed to investigate serum levels of heavy metals including essential elements [iron (Fe), zinc (Zn), copper (Cu), cobalt (Co), and manganese (Mn)], and nonessential elements [lead (Pb) and cadmium (Cd)] in patients with BP.

METHODS

The study included 25 patients with BP and 31 healthy volunteers. For each participant, serum levels of essential and nonessential elements were measured using the atomic absorption spectrophotometer method.

RESULTS

Serum levels of essential elements were significantly lower in the patient group compared to the control group (p < 0.001, for each). Serum levels of Pb increased in the patient group compared to the control group although no significant difference was achieved (p = 0.105). In contrast, serum Cd levels increased significantly in the patient group compared to the control group (p < 0.001).

CONCLUSION

Our findings suggest that decreased essential and increased nonessential elements may be associated with BP and thus, serum concentrations of these elements should be taken into account in BP. Studies are warranted to determine the role of these elements in treatment of BP.

Vitamin B12 Deficiency and the Nervous System: Beyond Metabolic Decompensation-Comparing Biological Models and Gaining New Insights into Molecular and Cellular Mechanisms

Vitamin B12 (VitB12) is a micronutrient and acts as a cofactor for fundamental biochemical reactions: the synthesis of succinyl-CoA from methylmalonyl-CoA and biotin, and the synthesis of methionine from folic acid and homocysteine. VitB12 deficiency can determine a wide range of diseases, including nervous system impairments. Although clinical evidence shows a direct role of VitB12 in neuronal homeostasis, the molecular mechanisms are yet to be characterized in depth. Earlier investigations focused on exploring the biochemical shifts resulting from a deficiency in the function of VitB12 as a coenzyme, while more recent studies propose a broader mechanism, encompassing changes at the molecular/cellular levels. Here, we explore existing study models employed to investigate the role of VitB12 in the nervous system, including the challenges inherent in replicating deficiency/supplementation in experimental settings. Moreover, we discuss the potential biochemical alterations and ensuing mechanisms that might be modified at the molecular/cellular level (such as epigenetic modifications or changes in lysosomal activity). We also address the role of VitB12 deficiency in initiating processes that contribute to nervous system deterioration, including ROS accumulation, inflammation, and demyelination. Consequently, a complex biological landscape emerges, requiring further investigative efforts to grasp the intricacies involved and identify potential therapeutic targets.

Nutritional peripheral neuropathies

Nutritional peripheral neuropathies are a global problem, heavily influenced by geopolitical, cultural and socioeconomic factors. Peripheral neuropathy occurs most frequently secondary to B-vitamin deficiencies, which is suspected to increase in years to come due to the popularity of vegan and vegetarian diets and increased use of bariatric surgery.This review will focus on the common B-vitamins for which a causal link to peripheral neuropathy is more established (vitamins B1, B2, B6, B9 and B12). We will review the historical human and animal data on which much of the clinical descriptions of vitamin deficiencies are based and summarise current available tools for accurately diagnosing a nutritional deficiency. We will also review recently described genetic diseases due to pathogenic variants in genes involved in B-vitamin metabolism that have helped to inform the phenotypes and potential causality of certain B-vitamins in peripheral neuropathy (B2 and B9).Endemic outbreaks of peripheral neuropathy over the last two centuries have been linked to food shortages and nutritional deficiency. These include outbreaks in Jamaican sugar plantation workers in the nineteenth century (Strachan's syndrome), World War two prisoners of war, Cuban endemic neuropathy and also Tanzanian endemic optic neuropathy, which remains a significant public health burden today. An improved understanding of lack of which vitamins cause peripheral neuropathy and how to identify specific deficiencies may lead to prevention of significant and irreversible disability in vulnerable populations.

Recent Advances in Dietary Sources, Health Benefits, Emerging Encapsulation Methods, Food Fortification, and New Sensor-Based Monitoring of Vitamin B12: A Critical Review

In this overview, the latest achievements in dietary origins, absorption mechanism, bioavailability assay, health advantages, cutting-edge encapsulation techniques, fortification approaches, and innovative highly sensitive sensor-based detection methods of vitamin B12 (VB12) were addressed. The cobalt-centered vitamin B is mainly found in animal products, posing challenges for strict vegetarians and vegans. Its bioavailability is highly influenced by intrinsic factor, absorption in the ileum, and liver reabsorption. VB12 mainly contributes to blood cell synthesis, cognitive function, and cardiovascular health, and potentially reduces anemia and optic neuropathy. Microencapsulation techniques improve the stability and controlled release of VB12. Co-microencapsulation of VB12 with other vitamins and bioactive compounds enhances bioavailability and controlled release, providing versatile initiatives for improving bio-functionality. Nanotechnology, including nanovesicles, nanoemulsions, and nanoparticles can enhance the delivery, stability, and bioavailability of VB12 in diverse applications, ranging from antimicrobial agents to skincare and oral insulin delivery. Staple food fortification with encapsulated and free VB12 emerges as a prominent strategy to combat deficiency and promote nutritional value. Biosensing technologies, such as electrochemical and optical biosensors, offer rapid, portable, and sensitive VB12 assessment. Carbon dot-based fluorescent nanosensors, nanocluster-based fluorescent probes, and electrochemical sensors show promise for precise detection, especially in pharmaceutical and biomedical applications.

Bilateral sixth nerve palsy with subdural hematoma: a unique presentation of B12 deficiency

Vitamin B12 is inextricably associated with the development and maintenance of neuronal functions. It is classically associated with subacute combined degeneration and peripheral neuropathy; however, cranial neuropathy is uncommon. We observed the rarest neurological manifestation of B12 deficiency. A 12 months infant had history of lethargy, irritability, anorexia, paleness, vomiting, and neurodevelopmental delay for 2 months. He also developed inattention and altered sleep pattern. His mother noticed bilateral inward rotation of both eyes. On examination, the infant had bilateral lateral rectus palsy. The infant was found to have anemia (7.7g/dL) and severe B12 deficiency (74pg/mL). On MRI, there was cerebral atrophy, subdural hematoma (SDH) and wide cisternal spaces and sulci. On supplementation with cobalamin, he improved clinically though mild restriction of lateral gaze on the left side persists. Follow up MRI showed significant improvement in cerebral atrophy with resolution of SDH. To date, such clinical presentation of B12 deficiency has never been reported. The authors suggest B12 supplementation for at risk population esp at antenatal stage and lactating mothers in national programs. The treatment of this condition should be initiated early to prevent long term sequelae.

Clinical impact and misdiagnosis of functional ophthalmological symptoms: a case report

BACKGROUND

There is a high prevalence of somatoform disorders and medically unexplained symptoms. When it comes to deciding whether a patient is able to work, it is essential to differentiate a somatoform disorder from a factitious disorder. The case presented demonstrates the impact on disability benefits and the subsequent psychosocial repercussions of misdiagnosing between a factitious disorder and a somatoform disorder.

CASE PRESENTATION

A 42-year-old Caucasian woman worked as a 100% fiduciary accountant until the age of 32 when she was placed on medical leave due to persistent trigeminal neuralgia. Afterward, she developed total blindness, not explained by a physiological process, accompanied by distress in a crucial emotional context. We evaluated the patient for a revision of a disability income after a diagnosis of factitious disorder with severe consequences such as disability income suspension and family conflict. Our psychiatric examination concluded the diagnoses of pain disorders related to psychological factors and a dissociative neurological symptom disorder with visual disturbance.

CONCLUSIONS

Blindness not explained by a physiological process may accompany trauma and psychological distress. Differentiating this pathology from factitious disorder or simulation is essential from an insurance medicine point of view, but also for its treatment.

Association Between Vitamin Deficiencies and Ophthalmological Conditions

Vitamin deficiencies can have adverse effects on health, including on the visual system. The ocular manifestations of a vitamin deficiency are related to the underlying biochemical function of the particular nutrient. While vitamin deficiencies are not common in developed counties, they are still prevalent in parts of the developing world and in specific, vulnerable populations. Vitamin deficiencies can cause or contribute to many ophthalmological conditions and eye diseases may even be the first presenting finding of a vitamin deficiency. As such, it is important for ophthalmologists to be aware of the ocular manifestations of vitamin deficiencies, especially given that the complications can be severe and effectively treated if identified early. This review summarizes the literature on the main vitamins known to have characteristic ocular manifestations: vitamins A, B1, B2, B9, B12, C, D, E and K. The function, epidemiology, manifestations, workup, and management of each vitamin is discussed in detail.

Nutritional Factors: Benefits in Glaucoma and Ophthalmologic Pathologies

Glaucoma is a chronic optic neuropathy that can lead to irreversible functional and morphological damage if left untreated. The gold standard therapeutic approaches in managing patients with glaucoma and limiting progression include local drops, laser, and/or surgery, which are all geared at reducing intraocular pressure (IOP). Nutrients, antioxidants, vitamins, organic compounds, and micronutrients have been gaining increasing interest in the past decade as integrative IOP-independent strategies to delay or halt glaucomatous retinal ganglion cell degeneration. In our minireview, we examine the various nutrients and compounds proposed in the current literature for the management of ophthalmology diseases, especially for glaucoma. With respect to each substance considered, this minireview reports the molecular and biological characteristics, neuroprotective activities, antioxidant properties, beneficial mechanisms, and clinical studies published in the past decade in the field of general medicine. This study highlights the potential benefits of these substances in glaucoma and other ophthalmologic pathologies. Nutritional supplementation can thus be useful as integrative IOP-independent strategies in the management of glaucoma and in other ophthalmologic pathologies. Large multicenter clinical trials based on functional and morphologic data collected over long follow-up periods in patients with IOP-independent treatments can pave the way for alternative and/or coadjutant therapeutic options in the management of glaucoma and other ocular pathologies.

Altered vitamin B12 metabolism in the central nervous system is associated with the modification of ribosomal gene expression: new insights from comparative RNA dataset analysis

Recent studies have confirmed the direct role of vitamin B12 (VitB12) in the central nervous system (CNS) homeostasis; nevertheless, the detailed mechanisms are poorly understood. By analyzing RNA-Seq and microarray datasets obtained from databanks, this study aims to identify possible basic mechanisms, related to the brain, involved in altering the gene expression under VitB12 deficiency mimicking conditions. The database inquiry returned datasets generated from distinctly heterogeneous experimental sets and considering the quality and relevance requirements, two datasets from mouse and one from rat models were selected. The analyses of individual datasets highlighted a change in ribosomal gene expression in VitB12 deficiency mimicking conditions within each system. Specifically, a divergent regulation was observed depending on the animal model: mice showed a down regulation of the ribosomal gene expression, while rats an upregulation. Interestingly, E2f1 was significantly upregulated under VitB12 deficiency mimicking conditions in the animal models, with a greater upregulation in rats. The rat model also revealed putative E2F1 Transcription Factor Binding Sites (TFBSs) in the promoter of the differently regulated genes involved in ribosomal gene expression. This suggested the possibility that E2F1, being greater expressed in rats, could activate the ribosomal genes having E2F1 TFBSs, thus giving a plausible explication to the divergent regulation observed in animal models. Despite the great diversity of the experimental sets used to generate the datasets considered, a common alteration of the ribosomes exists, thereby indicating a possible basic and conserved response to VitB12 deficiency. Moreover, these findings could provide new insights on E2F1 and its association with CNS homeostasis and VitB12 deficiency.

Electrophysiological assessment of nutritional optic neuropathy: a case report

PURPOSE

To report an unexpectedly asymmetric, progressive nutritional optic neuropathy associated with vitamin A deficient optic canal hyperostosis in a 15-year-old female with a long history of a restricted diet.

METHODS

We performed comprehensive ophthalmic assessments in a fifteen-year-old female with a long history of restricted eating who presented with suspected nutritional optic neuropathy, predominantly affecting the right eye vision.

RESULTS

A review of computerised tomography and magnetic resonance imaging revealed bilateral optic canal hyperostosis likely associated with vitamin A deficiency. Electrodiagnostic tests and optical coherence tomography provided structure-function evidence of bilateral retinal ganglion cell dysfunction and notably revealed severe loss of temporal fibres in the left eye which showed cecocentral scotoma but normal visual acuity. Although selective damage of the papillomacular bundle has been well-documented in nutritional and toxic optic neuropathies, compressive optic canal hyperostosis secondary to nutritional deficiency has been rarely reported.

CONCLUSIONS

Nutritional deficiencies are increasing in high-income countries and may be linked to the rise of gastrointestinal disorders, strict vegan and vegetarian diets and avoidant restrictive food intake disorder (ARFID) associated with conditions such as depression and autism spectrum syndrome (ASD). Our findings highlight the value of electrodiagnostic testing alongside imaging in complex nutritional optic neuropathies to help monitor, guide treatment and preserve remaining sight in a child.

Micronutrient Deficiencies Presenting with Optic Disc Swelling Associated with or without Intracranial Hypertension: A Systematic Review

Idiopathic intracranial hypertension (IIH) is a neurological disorder characterised by optic disc swelling secondary to raised intracranial pressure (ICP) of unknown cause. Obesity is the most established and prevalent risk factor in developed countries. As obesogenic diets are high in calories and nutrient-poor, there may be associated nutritional deficiencies that contribute to the clinical presentation of IIH. Yet none, aside from iron deficiency, are currently included in the inclusion or exclusion criteria for the diagnosis of IIH. Our primary aim was to determine which micronutrient deficiencies, aside from iron deficiency, could present with optic disc swelling associated with or without intracranial hypertension that could potentially meet current IIH diagnostic criteria. To this end, we conducted a systematic search of articles published between 1 January 1980 and 18 December 2020 reporting cases of optic disc swelling associated with micronutrient deficiencies. In total, 65 cases met the eligibility criteria from initial searches: all were case reports and case series with a high risk of bias. Our findings suggest that patients with IIH or unexplained optic disc swelling ought to be screened, investigated, and treated for associated micronutrient deficiencies in vitamin A, B1 and B12; and weight loss interventions in IIH patients ought to promote better nutrition in addition to overall calorie restriction.

Nanofortification of vitamin B-complex in food matrix: Need, regulations, and prospects

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Overview of nanomaterials to fortify food with vitamin B-complex.

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Nanofortification of food with vitamin B-complex to overcome conventional fortification challenges.

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Regulatory aspects, prospects, and upcoming trends of this indispensable technology are also discussed.

Micronutrient malnutrition (or hidden hunger) caused by vitamin B-complex deficiency is a significant concern in the growing population. Vitamin B-complex plays an essential role in many body functions. With the introduction of nanotechnology in the food industry, new and innovative techniques have started to develop, which holds a promising future to end malnutrition and help achieve United Nations Sustainable Developmental Goal-2 (UN SDG-2), named as zero hunger. This review highlights the need for nanofortification of vitamin B-complex in food matrix to address challenges faced by conventional fortification methods (bioavailability, controlled release, physicochemical stability, and shelf life). Further, different nanomaterials like organic, inorganic, carbon, and composites along with their applications, are discussed in detail. Among various nanomaterials, organic nanomaterials (lipid, polysaccharides, proteins, and biopolymers) were found best for fortifying vitamin B-complex in foods. Additionally, different regulatory aspects across the globe and prospects of this upcoming field are also highlighted in this review.

Wide Range Applications of Spirulina: From Earth to Space Missions

Spirulina is the most studied cyanobacterium species for both pharmacological applications and the food industry. The aim of the present review is to summarize the potential benefits of the use of Spirulina for improving healthcare both in space and on Earth. Regarding the first field of application, Spirulina could represent a new technology for the sustainment of long-duration manned missions to planets beyond the Lower Earth Orbit (e.g., Mars); furthermore, it could help astronauts stay healthy while exposed to a variety of stress factors that can have negative consequences even after years. As far as the second field of application, Spirulina could have an active role in various aspects of medicine, such as metabolism, oncology, ophthalmology, central and peripheral nervous systems, and nephrology. The recent findings of the capacity of Spirulina to improve stem cells mobility and to increase immune response have opened new intriguing scenarios in oncological and infectious diseases, respectively.

Vitamin intake and glaucoma risk: A systematic review and meta-analysis

There is currently a lack of high-quality research on the best dietary recommendations for patients with early glaucoma or at high risk for glaucoma. This meta-analysis aims to clarify the relationship between vitamin intake and glaucoma risk. Electronic databases, including PubMed, EMbase, ScienceDirect, Cochrane Database, Clinicaltrials.gov, and Google Scholar, were searched for publications indexed as of September 18, 2021. Data were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). The I² index was used to assess heterogeneity. We performed five meta-analyses of existing studies to summarize the evidence on the association between vitamin intake and glaucoma risk. The initial search identified 689 studies, eight of which (262,189 patients) met the eligibility criteria for the meta-analysis. The data showed that high-dose intake of vitamins A (OR=0.63, 95%CI [0.53, 0.76]) and B (OR=0.71, 95%CI [0.64, 0.80]) but not vitamins C (OR=0.69, 95%CI [0.48, 1.01]), D (OR=0.90, 95%CI [0.45, 1.83]), or E (OR=0.91, 95%CI [0.71, 1.16]) was associated with a low prevalence of glaucoma. The results of this study demonstrated that high-dose intake of vitamins A and B, but not vitamins C, D, or E, was associated with a low prevalence of glaucoma.

Vitamins are Indeed Vital Amines: A Discussion of 3 Deficiencies With Neurologic Manifestations

Optimal functioning of the human nervous system depends on a constant supply of nutrients, vitamins, and minerals. In the developed world, nutritional deficiencies are relatively rare and infrequently present with neurologic manifestations. These neurologic disorders can be mistaken for inflammatory and/or autoimmune phenomena. This manuscript describes 2 pediatric cases with neurologic signs/symptoms arising from vitamin deficiencies-(1) optic neuropathy and (2) Wernicke encephalopathy associated with a Guillain-Barre-like pattern of weakness. The 2 cases and the subsequent discussion of vitamin A, B1, and B12 deficiencies underscore the value of taking a thorough dietary history and emphasize risk factors for these 3 nutritional deficiencies.

Bilateral Optic Atrophy in a Young Patient With Chronic Anaemia Secondary to End-Stage Renal Disease

End-stage renal disease (ESRD) is associated with a number of serious complications, including increased cardiovascular disease, anaemia and metabolic bone disease. Optic atrophy secondary to chronic anaemia in ESRD is rare. We report a case of bilateral optic atrophy in a young patient with chronic anaemia secondary to ESRD. A 23-year-old lady with ESRD, presented with progressive blurring of vision in her left eye for a period of six months. Visual acuity in the left eye was counting finger and the right eye was 6/6. Left optic nerve functions were significantly reduced. Bilateral anterior segments and intraocular pressure were normal. Funduscopy showed bilateral pale disc with arteriolar attenuation. The infective, autoimmune and demyelinating screening were negative. Serial full blood count indicated low haemoglobin and haematocrit value. The full blood picture revealed normocytic normochromic anaemia. Neuroimaging was normal. The patient was diagnosed as having bilateral optic atrophy secondary to chronic anaemia due to ESRD. Chronic anaemia is a potential cause of optic atrophy in a young patient with chronic disease. Management of anaemia in such cases is crucial to prevent irreversible complications including optic atrophy and blindness.

Current Nanocarrier Strategies Improve Vitamin B12 Pharmacokinetics, Ameliorate Patients' Lives, and Reduce Costs

Vitamin B12 (VitB12) is a naturally occurring compound produced by microorganisms and an essential nutrient for humans. Several papers highlight the role of VitB12 deficiency in bone and heart health, depression, memory performance, fertility, embryo development, and cancer, while VitB12 treatment is crucial for survival in inborn errors of VitB12 metabolism. VitB12 is administrated through intramuscular injection, thus impacting the patients’ lifestyle, although it is known that oral administration may meet the specific requirement even in the case of malabsorption. Furthermore, the high-dose injection of VitB12 does not ensure a constant dosage, while the oral route allows only 1.2% of the vitamin to be absorbed in human beings. Nanocarriers are promising nanotechnology that can enable therapies to be improved, reducing side effects. Today, nanocarrier strategies applied at VitB12 delivery are at the initial phase and aim to simplify administration, reduce costs, improve pharmacokinetics, and ameliorate the quality of patients’ lives. The safety of nanotechnologies is still under investigation and few treatments involving nanocarriers have been approved, so far. Here, we highlight the role of VitB12 in human metabolism and diseases, and the issues linked to its molecule properties, and discuss how nanocarriers can improve the therapy and supplementation of the vitamin and reduce possible side effects and limits.