Polycythemia Vera Masked by Megaloblastic Anemia.

Polycythemia vera (PV) is a chronic myeloproliferative disorder characterized by uncontrolled red blood cell production. Megaloblastic anemia is caused by deficiency of cobalamin (vitamin B12) and/or folate (vitamin B9). While B12 deficiency may be caused by insufficient dietary intake or impairment of its utilization, its association with PV is described without exact knowledge of the physiopathology. We herein report the occurrence of megaloblastic anemia due to Vitamin B12 deficiency in an 85-year-old North African woman patient with PV. This case highlights this atypical presentation of PV and challenges that comes with it causing the delay of diagnosis and the complexity of its diagnosis and treatment. Keywords: megaloblastic anemia, polycythemia vera, association, case report.

Emerging Roles of Vitamin B12 in Aging and Inflammation.

Vitamin B12 (cobalamin) is an essential nutrient for humans and animals. Metabolically active forms of B12-methylcobalamin and 5-deoxyadenosylcobalamin are cofactors for the enzymes methionine synthase and mitochondrial methylmalonyl-CoA mutase. Malfunction of these enzymes due to a scarcity of vitamin B12 leads to disturbance of one-carbon metabolism and impaired mitochondrial function. A significant fraction of the population (up to 20%) is deficient in vitamin B12, with a higher rate of deficiency among elderly people. B12 deficiency is associated with numerous hallmarks of aging at the cellular and organismal levels. Cellular senescence is characterized by high levels of DNA damage by metabolic abnormalities, increased mitochondrial dysfunction, and disturbance of epigenetic regulation. B12 deficiency could be responsible for or play a crucial part in these disorders. In this review, we focus on a comprehensive analysis of molecular mechanisms through which vitamin B12 influences aging. We review new data about how deficiency in vitamin B12 may accelerate cellular aging. Despite indications that vitamin B12 has an important role in health and healthy aging, knowledge of the influence of vitamin B12 on aging is still limited and requires further research.

Characterizing Vitamin B12 Deficiency in Neurology Outpatients: A Retrospective Observational Study.

OBJECTIVES: Clinical manifestations of vitamin B12 deficiency are varied and may result in missed or delayed diagnosis. This investigation explores the diverse clinical manifestations and demographic characteristics of vitamin B12 deficiency in neurology outpatients, aiming to enhance timely diagnosis and outcomes. METHODS: The severity of vitamin B12 deficiency was classified as absolute (≤150 pg/mL) or borderline deficiency (150-300 pg/mL). We conducted a retrospective analysis of 165 outpatients with vitamin B12 deficiency at the department of neurology between May 2020 and May 2021. RESULT: Absolute vitamin B12 deficiency was found in 23.0% of the patients. The most common age range was 50-60 years, the most common cause was vegetarianism, and the most common symptom was headache. Epileptiform symptoms were more likely to occur in younger patients (<20 years old) with vitamin B12 deficiency, whereas psychiatric symptoms were more likely to occur in older patients (>70 years old). Vegetarians, salivation, and nonmegaloblastic anemia were more obvious in patients with absolute vitamin B12 deficiency, whereas headaches often showed borderline B12 deficiency. CONCLUSIONS: The clinical characteristics of vitamin B12 deficiency are complex and nonspecific. The diagnosis should be based on multiple factors.

Nitrous Oxide-induced Myeloneuropathy Due to Recreational Abuse.

BACKGROUND: The recreational use of nitrous oxide (N2O) has increased in recent years with a noticeable surge in the incidence of nitrous oxide-related myeloneuropathy. OBJECTIVES: To raise awareness of increasing myeloneuropathy due to recreational nitrous oxide misuse in Israel. METHODS: We conducted a case series documenting the clinical and investigative features of eight patients presenting with nitrous oxide-induced myeloneuropathy who were admitted to our departments. RESULTS: Paresthesia was the chief complaint in all patients, with sensory gait ataxia being a common feature, which was often accompanied by Romberg's sign and mild lower limb weakness. Vitamin B12 levels were below the normal range in seven patients, accompanied by elevated homocysteine and methylmalonic acid levels. Magnetic resonance imaging scans revealed hyperintense signals in the dorsal columns of the cervical spine. All patients improved following vitamin B12 injections. CONCLUSIONS: Enhancing awareness, prompting the use of appropriate investigations, and advocating for timely treatment are needed to overcome the risks associated with nitrous oxide misuse.

NMR Spectroscopy in Diagnosis and Monitoring of Methylmalonic and Propionic Acidemias.

Although both localized nuclear magnetic resonance spectroscopy (MRS) and non-localized nuclear magnetic resonance spectroscopy (NMR) generate the same information, i.e., spectra generated by various groups from the structure of metabolites, they are rarely employed in the same study or by the same research group. As our review reveals, these techniques have never been applied in the same study of methylmalonic acidemia (MMA), propionic acidemia (PA) or vitamin B12 deficiency patients. On the other hand, MRS and NMR provide complementary information which is very valuable in the assessment of the severity of disease and efficiency of its treatment. Thus, MRS provides intracellular metabolic information from localized regions of the brain, while NMR provides extracellular metabolic information from biological fluids like urine, blood or cerebrospinal fluid. This paper presents an up-to-date review of the NMR and MRS studies reported to date for methylmalonic and propionic acidemias. Vitamin B12 deficiency, although in most of its cases not inherited, shares similarities in its metabolic effects with MMA and it is also covered in this review.

Vitamin B12 deficiency presenting as neck pain and cervical radiculopathy.

Vitamin B12 is required for the formation of haematopoietic cells and the synthesis of myelin. Deficiency typically presents with fatigue and megaloblastic anaemia. Prolonged deficiency can cause neurological symptoms such as paresthesia, which can progress to subacute combined degeneration of the spinal cord. We describe an unusual presentation of B12 deficiency in a young man who was initially diagnosed and treated for cervical radiculopathy. This case highlights the challenges of diagnosing B12 deficiency in patients with neurologic but without haematologic, abnormalities. While the current incidence of B12 deficiency in developed countries is low, cases are likely to rise with the increased adoption of veganism. Clinicians should be aware of the variable presentations of B12 deficiency because delayed diagnosis and treatment increases morbidity and can cause irreversible neurological deficits.

Vitamin B12 deficiency and neuropsychiatric symptoms in Lebanon: A cross-sectional study of vegans, vegetarians, and omnivores.

BACKGROUND: Vitamin B12 deficiency is responsible for a variety of complications, particularly neurological/neuropsychiatric complications, including depression, irritability, paresthesia and insomnia. Since vitamin B12 is found in animal-derived products, vegans/vegetarians are at a greater risk for developing vitamin B12 deficiency. AIMS: This study aims to investigate the occurrence of vitamin B12 deficiency among a sample of adult Lebanese population, with a particular emphasis on assessing the severity of its neurological/neuropsychiatric signs and symptoms, especially among vegans/vegetarians. METHODOLOGY: A cross-sectional study was conducted among a sample of 483 Lebanese adults. Data was collected through a standardized questionnaire that included socio-demographic characteristics, the Patient Health Questionnaire-9 (PHQ-9), Generalized anxiety disorders-7 (GAD-7), and the Insomnia Severity Index (ISI) scales. RESULTS: Among the participants, 11.4% were in the vegan/vegetarian group, and about 43.1% had vitamin B12 deficiency. After analyzing the PHQ-9, GAD-7 and ISI total scores, higher scores were reported in participants with vitamin B12 deficiency, compared to individuals with normal vitamin B12 serum levels (p < 0.001). Regarding the diet type, vegans/vegetarians were more susceptible to developing depression compared to omnivores (mean scores of 11.92 vs 8.02 on the PHQ-9 scale, respectively, with p < 0.001). Of the patients with vitamin B12 deficiency, 81.1% reported having paresthesia compared to 43.7% of individuals with no vitamin B12 deficiency (p < 0.001). CONCLUSION: Vitamin B12 deficiency in Lebanon is notably high and is linked to an increased risk of developing depression, generalized anxiety disorder, insomnia, and paresthesia. Vegans/vegetarians exhibit a higher susceptibility to developing depression compared to omnivores, whereas the risk of developing insomnia, generalized anxiety disorder and paresthesia was statistically insignificant when comparing vegans/vegetarians to omnivores.

Vitamin B12 deficiency in diabetic patients treated with metformin: A cross-sectional study.

Metformin is a cornerstone medication in the management of type 2 diabetes. Metformin is safe, effective, and inexpensive; however, it is associated with vitamin B12 deficiency. This study set out to evaluate the rate of vitamin B12 deficiency in Vietnamese patients with type 2 diabetes who were treated with metformin and to investigate factors associated with vitamin B12 deficiency. This is a cross-sectional study that was conducted in Vinmec Central Park Hospital from February to June 2023. The clinical and paraclinical characteristics of the participants were recorded, and the levels of vitamin B12 and folate were measured. The rate of vitamin B12 deficiency in patients treated with metformin was found to be 18.6%. Further, the duration of diabetes, duration of metformin use, metformin dose, and hemoglobin levels were statistically associated with vitamin B12 deficiency with OR (95% CI) = 1.12 (1.03-1.19), 1.01 (1.00-1.02), 1.002 (1.001-1.002), 0.74 (0.55-0.99), respectively. After adjusting for covariates, a metformin dose greater than the median dose remained the only parameter associated with vitamin B12 deficiency, with OR (95% CI) = 4.10 (1.62-10.36). Moreover, when combining both long-term use of metformin and a metformin dose greater than the median dose, the OR increased to 5.25 (95% CI: 2.11-13.15). These results demonstrate that vitamin B12 deficiency in patients treated with metformin is quite prevalent in Vietnam and that those with long-term use of metformin (48 months or more) and high metformin dose (1000 mg/day or more) are at high risk of experiencing this adverse effect and so require screening.

Vitamin B12 deficiency-induced megaloblastic anemia in a pediatric patient with autism spectrum disorder with a chronically unbalanced diet.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by a lack of behavioral flexibility and stereotyped language. Food selectivity is common among children with ASD because of their persnickety nature. A prolonged unbalanced diet results in an increased risk of several diseases, such as iron deficiency anemia, scurvy, rickets, dry eye, and Wernicke encephalopathy. However, no cases of megaloblastic anemia have been reported to date. We report the case of an 11-year-old boy with ASD who developed megaloblastic anemia due to vitamin B12 deficiency. He had a prolonged history of selective eating for more than 10 years. His nutritional status on admission was poor, and he had low weight and short stature. His food selectivity was so strong that intervention to expand diet variety was unsuccessful. A developmental-behavioral pediatrician found that the patient had visual dominance and could take some medications when suffering from a minor illness. Nutritional supplements were selected after consultation with a nutritionist. Although compulsory treatment was necessary during the acute phase, the therapy was continued at home. With multidisciplinary intervention tailored to the patient and his parents' characteristics, his nutritional status improved in a few months.

New data supporting that early diagnosis and treatment are possible and necessary in intracellular cobalamin depletion: the case of transcobalamin II deficiency.

OBJECTIVES: Transcobalamin II (TC) promotes the cellular uptake of cobalamin (Cbl) through receptor-mediated endocytosis of the TC-cbl complex in peripheral tissues. TC deficiency is a rare disorder that causes intracellular Cbl depletion. It presents in early infancy with a failure to thrive, diarrhea, anemia, agammaglobulinemia, and pancytopenia. Data from five TC-deficient patients including clinical, biochemical, and molecular findings, as well as long-term outcomes, were collected. CASE PRESENTATION: Mutation analysis revealed one unreported pathogenic variant in the TCN2 gene. One patient had exocrine pancreatic insufficiency. We conducted a retrospective analysis of C3 and C3/C2 from dried blood samples, as this is implemented for newborn screening (NBS). We detected a marked increase in the C3/C2 ratio in two samples. Treatment was based on parenteral Cbl. Three patients treated before six months of age had an initial favorable outcome, whereas the two treated later or inadequately had neurological impairment. CONCLUSIONS: This is the first report of Argentinean patients with TC deficiency that detected a new variant in TCN2. NBS may be a tool for the early detection of TC deficiency. This data emphasizes that TC deficiency is a severe disorder that requires early detection and long-term, aggressive therapy. Accurate diagnosis is imperative, because early detection and treatment can be life-saving.

Iron deficiency in pernicious anemia: Specific features of iron deficient patients and preliminary data on response to iron supplementation.

BACKGROUND & AIMS: While vitamin B12 (B12) deficiency is considered as the hallmark of pernicious anemia (PA), iron deficiency (ID) is also prevalent. Indeed, this auto immune gastritis is responsible for parietal cell atrophy and increase in gastric pH, leading to impaired iron absorption. We compared PA patients' features according to their iron status at PA diagnosis, and we assessed the iron status recovery after oral or intravenous iron supplementation. METHODS: We prospectively included patients presenting with a newly diagnosed PA in a tertiary referral hospital between November 2018 and October 2020. Iron status was assessed at PA diagnosis then regularly during a standardized follow-up. In case of ID, the decision of treatment with oral and/or intravenous iron supplementation was left to the clinician convenience. RESULTS: We included 28 patients with newly diagnosed PA. ID was observed in 21/28 (75.0%) patients: from the PA diagnosis in 13 patients, or during the follow-up in 8 patients. Iron deficient PA patients had higher plasma B12 (p = 0.04) and lower homocysteine levels (p = 0.04). Also, ID was independently associated with the 'APCA (anti-parietal cell antibodies) alone' immunological status (absence of anti-intrinsic factor antibodies) after adjustment for age, gender and B12 level (aOR 12.1 [1.1-141.8], p = 0.04). High level of APCA was associated with lower ferritin level. After 3 months of supplementation, 3/11 PA patients normalized the iron status with oral iron supplementation, versus 7/8 with intravenous iron supplementation (p = 0.02). CONCLUSION: The high frequency of iron deficiency in PA highlights the interest of regular assessment of iron status in this condition. ID was associated with a profile including APCA alone and less pronounced B12 deficiency. Intravenous iron supplementation seemed to be more efficient than an oral supplementation in these preliminary data.

Macro-B12 and Unexpectedly High Levels of Plasma B12: A Critical Review.

A low total plasma vitamin B12 supports a clinical suspicion of B12 deficiency, while the interpretation of an unexpectedly normal/high level is marred by controversies. Here, we critically review current knowledge on B12 in blood plasma, including the presence of the so-called "macro-B12". The latter form is most often defined as the fraction of B12 that can be removed by precipitation with polyethylene glycol (PEG), a nonspecific procedure that also removes protein polymers and antibody-bound analytes. Plasma B12 includes B12 attached to transcobalamin and haptocorrin, and an increased concentration of one or both proteins almost always causes an elevation of B12. The total plasma B12 is measured by automated competitive binding assays, often incorrectly referred to as immunoassays, since the binding protein is intrinsic factor and not an antibody. An unexpectedly high level of B12 may be further explored using immunological measurements of haptocorrin and transcobalamin (optionally combined with e.g., size-exclusion chromatography). Nonspecific methods, such as PEG precipitation, are likely to give misleading results and cannot be recommended. Currently, the need for evaluation of a high B12 of unknown etiology is limited since other tests (such as measurements of methylmalonic acid) may better guide the diagnosis of B12 deficiency.

Association between vitamin B12 deficiency and risk of Paediatric narcolepsy: Evidence from cross-sectional study and Mendelian randomization analysis.

BACKGROUND: Narcolepsy, a chronic neurologic sleep disorder, has sparked growing interest in the potential role of vitamin B12 in its pathogenic mechanism. However, research on this association has predominantly focused on adults. Our objective was to delineate the phenotypic and genetic connections between serum vitamin B12 levels and paediatric narcolepsy. METHODS: To investigate the causal relationship between vitamin B12 and paediatric narcolepsy, we conducted a retrospective analysis involving 60 narcolepsy patients and a matched control group. Univariate and multivariate logistic regression models were employed to identify independent factors influencing paediatric narcolepsy. Furthermore, a bidirectional two-sample Mendelian randomization (MR) analysis was performed to assess the causal connection between serum vitamin B12 levels and narcolepsy. RESULTS: Paediatric narcolepsy patients showed significantly lower serum levels of vitamin B12 and folate compared to the control group (P < 0.05). Multivariate logistic regression analysis identified serum vitamin B12 as the exclusive independent factor influencing paediatric narcolepsy (P < 0.001; OR = 0.96; 95%CI: 0.94-0.98). Additionally, IVW model results provided compelling evidence supporting a potential causal association between serum vitamin B12 levels and paediatric narcolepsy (OR: 0.958, 95% CI = 0.946-0.969, P = 0.001). CONCLUSION: This study establishes connections at both phenotypic and genetic levels, associating vitamin B12 deficiency with an increased risk of paediatric narcolepsy. These findings provide innovative perspectives for clinical strategies in the prevention and treatment of narcolepsy.

Hematological parameters in patients with recurrent Aphthous Stomatitis: a systematic review and meta-analysis.

OBJECTIVES: Recurrent Aphthous Stomatitis (RAS) known as recurrent aphthous ulcer is a common and painful ulcerations in oral cavity. It has been suggested that hematological parameters seems to be considered as an etiologic factor. So, this meta-analysis and systematic review was aimed to examine the relationship between RAS and hematological parameters. METHODS: Relevant studies were found using online international databases including Scopus, Science direct, Web of science (ISI), PubMed, and Google Scholar search engine between 2000 and October 2023. The quality of all papers was determined by NOS checklist. Heterogeneity between the results of primary studies was evaluated with I-square index and publication bias was performed by Egger's test and funnel plots. Also, sensitivity analysis was done to check the effect of each of the primary studies on the overall estimate. Also, the statistical analyses were done using Stata software Ver. 11. RESULTS: By combining the results of primary studies, the standardized mean difference (SMD) of vitamin B12, ferritin, folic acid, hemoglobin, iron and zinc indices with a 95% confidence interval (CI) between the case (patients with RAS) and control (Healthy) groups were estimated -0.52(-0.89, -0.14), -0.20(-0.51, 0.11), -0.42(-0.95, 0.11), -0.58(-0.90, -0.27), 0.01(-0.12, 0.15), -0.33(-0.81, 0.14) respectively. The patients with vitamin B12, ferritin, folic acid, and iron deficiencies and reduced hemoglobin (Hb) level reported 2.93(2.28, 3.78), 2.50(1.48, 4.22), 1.51(0.53, 4.29), 1.46(0.70, 3.03), and 2.14(1.38, 3.32), times more susceptible to develop RAS than healthy individuals. CONCLUSION: The results of the meta-analysis indicated that the SMD of vitamin B12 serum and Hb levels in the case group was 52%. Our result have also showed that the odds ratio of vitamin B12, ferritin deficiencies, and decreased Hb level in case group was 2.93, 2.50, and 2.14 times more than healthy group.

Severe Hemolytic Anemia: Atypical Presentation of Cobalamin Deficiency.

Two severe cases of hemolytic anemia are described in different pediatric age groups, both linked to severe cobalamin deficiency from distinct causes. The first case refers to an exclusively breastfed infant with vitamin deficit secondary to maternal impaired absorption. Apart from the neurological deficits present at diagnosis, he also presented with infantile epileptic spasms syndrome a few months after treatment while having normal cobalamin serum levels. The second case refers to an adolescent with long-term inadequate intake. The occurrence of severe hemolytic anemia in cobalamin deficiency is exceptionally rare.

Nitrous oxide induced subacute combined degeneration of the spine cord: A case report.

RATIONALE: In recent years, recreational use of inhaled nitrous oxide (N2O) is on the increase among young people, accompanied by a corresponding rise in reports about its toxicity. Subacute combined degeneration of the spine cord (SCD) is the typical clinical picture of the nervous system disorder caused by N2O intoxication, as a result of metabolic disturbance of vitamin B12. PATIENT CONCERNS, DIAGNOSES, INTERVENTIONS AND OUTCOMES: We report a 28-year-old female of SCD due to prolonged use of N2O, presented with paresthesia and unsteady in walking progressing within 1 month. Symptoms gradually improved with the treatment of intramuscular injections of hydroxocobalamin combined with N2O abstinence, and the patient recovered completely with normal neurological examination after 4 months of follow-up. LESSONS: Clinicians should be aware of the clinical features and pathogenesis of SCD caused by N2O intoxication in order to lead effective treatment as soon as possible. Recreational N2O use should always be considered as an etiology when dealing with patients presented with myelopathy and/or neuropathy suspected of vitamin B12 deficiency.