Diagnostic value of oral "beefy red" patch combined with fingertip blood mean corpuscular volume in vitamin B12 deficiency

OBJECTIVES

To investigate the diagnostic value of accessible fingertip mean corpuscular volume (MCV) combined with a visible "beefy red" patch in the diagnosis of vitamin B12 (VB12) deficiency in local clinics and hospitals without in-house clinical laboratories, especially in remote areas.

MATERIALS AND METHODS

The medical history data of patients complaining of oral mucosal pain at the Stomatological Hospital of Southern Medical University were reviewed. All included patients underwent fingertip blood routine examination, specific serological test (serum VB12, folic acid, iron, and ferritin), and detailed oral clinical examinations. According to the results of the serum VB12 test patients were divided into case and control groups. In diagnostic test, the diagnostic value of the "beefy red" patch and elevated MCV in VB12 deficiency was evaluated by the receiver operator characteristic curve.

RESULTS

There were more female patients than male patients in the case group (serum VB12 level < 148 pmol/L, n = 81) and control group (serum VB12 level ≥ 148 pmol/L, n = 60), mostly middle-aged and elderly patients. There were no statistical differences in gender and age between the two groups. In the case group, the number of individuals with stomach disease was 13, the number of individuals with "beefy red" patch was 78, the number of individuals with oral ulcer was 29, the number of individuals with "MCV > 100fL" and "folic acid < 15.9 nmol/L" were respectively 68 and 5. All were more than that in control group (P < 0.05). The diagnostic test, "beefy red patch" has high sensitivity (0.963) but low specificity(0.883), "MCV > 100 fL" has high specificity (0.933) but low specificity (0.815), and "MCV > 100 fL combined with beefy red patch" has maximal specificity (0.950), and area under the curve (0.949).

CONCLUSIONS

Visible oral "beefy red" patch combined with accessible fingertip blood MCV could improve the rate of diagnosis in VB12 deficiency, especially in the elderly in local clinics and hospitals without in-house clinical laboratories in China, which is conducive to early disease detection and treatment.

Vitamin B12 levels in patients with retinal vein occlusion and their relation with clinical outcome: a retrospective study

Retinal vein occlusion (RVO) is the second most common retinal vascular disorder, after diabetic retinopathy. Most patients suffering RVO develop some degree of visual loss consequent to retinal complications such as edema and microhemorrhages. Even if some risk factors for RVO have been identified, the clinical outcome of RVO remains highly unpredictable because studies investigating potential prognostic markers for visual improvement are lacking. Cyanocobalamin belongs to the group of B vitamins and plays a role in homocysteine metabolism; however, cyanocobalamin deficiency associates with an increase of some toxic bioproducts involved in endothelial injury and platelet activation independent of homocysteine levels. We retrospectively evaluated the levels of vitamin B12 at diagnosis in 203 patients with RVO, and in a parallel cohort of 120 age- and sex-matched patients without RVO from an internal medicine ward, and correlated them with visual outcome at follow-up (median time 150 days, IQR 30-210). In patients with RVO, vitamin B12 levels at diagnosis were significantly lower than in controls and independently predicted worse clinical outcome at multivariate analysis (OR 3.2; CIs 1.2-8.2; p = 0.015). Our data suggest the opportunity to prospectively evaluate the effect on visual outcome of cyanocobalamin supplementation in RVO patients.

Structural and Functional Brain Changes Associated with Vitamin B12 Deficiency using Magnetic Resonance Imaging: A systematic review and meta-analysis

AIM

This review was conducted to assess the structural and functional brain changes associated with vitamin B12 deficiency in different age groups using MRI.

METHODS

PubMed, Embase, Medline, CINAHL, Scopus, Web of Science, and Google Scholar were searched for magnetic resonance imaging [MRI] studies that explored structural and functional brain changes associated with vitamin B12 deficiency in different age groups. The inclusion criteria were as follows: [1] the population consisted of people and not animals; [2] patients with known B12 deficiency; [3] English publications; [3] at least one of the following brain MRI techniques had been employed: VBM, DWI, DTI, fMRI, or rs-fMRI. However, case reports, systematic reviews and meta-analysis were excluded.

RESULTS

Twelve articles met the inclusion criteria. The results of my review show a connection between vitamin B12 deficiency and abnormal structural and functional brain changes in several brain regions. These changes were observed in different age groups ranging from a mean age of seven years to a mean age in the 70s. The results also highlight the association between brain changes and cognitive decline among affected subjects. Improvements in damaged brain regions post-vitamin B12 treatment were also studied.

CONCLUSION

Structural and functional brain damage was found to be associated with vitamin B12 deficiency in all age groups. Vitamin B12 treatment may lead to partial or complete structural and/or functional recovery, as well as a cognitive recovery.

Neuropsychiatric manifestations in vitamin B12 deficiency

Vitamin B12 deficiency can have distressing neuropsychiatric symptoms. It can have an etiological role in clinical presentations like depression, anxiety, psychosis, dementia, and delirium, requiring screening of at-risk populations. Few mechanisms that underlie the neuropsychiatric manifestations of B12 deficiency include alteration in one-carbon metabolism, genetic vulnerability, and alteration in folate metabolism. Maintaining a high serum B12 level in elderly can be protective against Alzheimer's disease (AD). In an established AD, its deficiency is associated with higher cognitive decline and risk for delirium. The other mental changes associated with B12 deficiency include apathy, agitation, impaired concentration, insomnia, persecutory delusions, auditory and visual hallucinations, and disorganized thought-process. Besides serum vitamin B12, plasma methylmalonic acid (MMA) and homocysteine helps in diagnosis. The chapter focuses on early recognition and effective treatment of these neuropsychiatric manifestations of vitamin B12 deficiency.

Vitamin B12 (Cobalamin) Deficiency in Overt and Subclinical Primary Hypothyroidism

Background:

B12 (cobalamin) deficiency has been reported in hypothyroid patients with variable prevalence rates thus routine screening of hypothyroid patients was recommended by some and discouraged by others. We aimed to assess the prevalence of B12 deficiency among hypothyroid patients and to evaluate for pernicious anemia and celiac disease as etiologies.

Methods:

A total 133 patients were included. Thyroid hormones and thyroid peroxidase (TPO) autoantibodies were measured. Serum B12 was measured and if deficient, intrinsic factor antibodies (IFAB) and tissue transglutaminase (tTG) antibodies were evaluated.

Results:

Our study included 45 patients with overt hypothyroidism (OH), 48 patients with subclinical hypothyroidism (SCH), and 40 patients as controls. Mean age was 34.3 years and 82% were females. TPO antibodies were positive in 73.5% of OH and 51.1% of SCH patients. B12 deficiency was detected in 33.3%, 47.9%, and 37.5% of OH, SCH, and controls, respectively with no significant difference (P = .334). Borderline-to-low B12 level was more prevalent in the OH and the SCH groups compared to controls (68.9%, 85.4%, and 57.5%, respectively; P = .014). Among B12-deficient hypothyroid patients, 7.5% had positive IFAB and 13.3% had positive tTG antibodies. We did not find a significant association of TPO positivity and B12 deficiency (OR, 0.69; 95% CI 0.3-1.57; P = .147).

Conclusion:

We did not find a higher prevalence of B12 deficiency among hypothyroid patients nor an association with TPO positivity. Borderline B12 levels were more prevalent among hypothyroid patients.

Early autoimmune gastritis presenting with a normal endoscopic appearance

This report describes a patient with early-stage autoimmune gastritis (AIG) presenting with a normal endoscopic appearance. A 66-year-old man with autoimmune thyroiditis was suspected of having AIG because of a previous history of vitamin B12 deficiency when receiving steroid therapy for interstitial pneumonia 5 years earlier. At presentation, he tested positive for anti-parietal cell antibody (1:320) and anti-intrinsic factor antibody, but not for vitamin B12 deficiency. His gastrin level was elevated (338 pg/mL), but his pepsinogen (PG) I level (56.1 ng/mL) and PGI/PGII ratio (7.6) were normal. Endoscopically, neither atrophic nor inflammatory changes were observed. Histopathologic examination, however, showed mild atrophic changes with dense lymphocytic infiltration in the deep lamina propria and focal destruction of parietal cells in the greater curvature of the corpus. PGI-positive/MUC6-positive pseudo-pyloric metaplasia was observed in the area from which H⁺/K⁺-ATPase-positive parietal cells had disappeared. Chromogranin A immunostaining showed linear hyperplasia of enterochromaffin-like cells. By contrast, atrophic changes were not evident in the lesser curvature of the corpus, except for mild lymphocytic infiltration around and into the fundic glands. These serological and histopathological findings suggested that the patient had early-stage AIG with a normal endoscopic appearance.

Evaluation of the response to vitamin B12 supplementation in patients with atrophy in sleeve gastrectomy materials

OBJECTIVE

Vitamin B12 deficiency can be seen in the cases with sleeve gastrectomy. Because the chief factor in vitamin B12 deficiency is gastric atrophy, we aimed to evaluate the effect of atrophy on postoperative vitamin B12 levels in patients who underwent sleeve gastrectomy.

MATERIAL AND METHODS

Sixty patients were included in this study. Vitamin B12 levels were compared with presence of atrophy before the operation and after vitamin B12 supplementation.

RESULTS

Atrophy was observed in 37 (61.7%) of the cases; 23 (38.3%) patients had no atrophy. There was a statistically significant difference between the presence of atrophy and vitamin B12 levels (p = 0.024). Despite vitamin B12 support, there were statistically significant low vitamin B12 levels after the operation in female patients having atrophy (p = 0.023). The same significance was not observed in males (p = 0.480).

CONCLUSION

Vitamin B12 deficiency following obesity surgery is a condition that must be monitored and prevented. We found that histopathologically confirmed atrophy had an adverse effect on postoperative vitamin B12 levels. These findings can be a guide for the clinicians in the management of these cases.

Micronutrient's deficiency in India: a systematic review and meta-analysis

India is coming to grips with a stage of nutrition transition. According to the Food Safety and Standards Authority of India (FSSAI), preventable micronutrient deficiency is arising public health precedence in India. However, the foremost public health concern is the lack of national prevalence data. The present study was carried out to estimate the pooled age-wise prevalence of six preventable micronutrient deficiencies (vitamin A, vitamin B₁₂, vitamin D, iron, iodine and folic acid) in India. A systematic review was carried out on PubMed and Global Index Medicus databases using the Boolean search strategy. Statistical analyses were done using R software, version 3.6. 2. PRISMA guidelines were strictly adhered to during the review. A preliminary literature search yielded 4302 articles; however, 270 original research articles were found eligible to be included in quantitative synthesis. The estimated overall prevalence was 17 % [95 % confidence interval (CI) 0⋅07, 0⋅26] for iodine deficiency, 37 % (95 % CI 0⋅27, 0⋅46) for folic acid deficiency, 54 % (95 % CI 0⋅49, 0⋅59) for iron deficiency, 53 % (95 % CI 0⋅41, 0⋅64) for vitamin B₁₂ deficiency, 19 % (95 % CI 0⋅09, 0⋅29) for vitamin A deficiency and 61 % (95 % CI 0⋅07, 0⋅26) for vitamin D with high heterogeneity. We classified the population into infants (0–5 years), adolescents (<18 years), adults (>18 years) and pregnant women. Iron deficiency was most prevalent (61 %) in pregnant women. The results of the present study reinforce the data on micronutrient deficiency in India and warrant the immediate need for further active public health interventions to address these deficiencies. The study is registered with PROSPERO (CRD42020205043).

Impact of Correcting Nutritional Deficiency Anemias in the Elderly on Hospitalizations, Falls, and Mortalities

Background

The incidence and prevalence of anemia increase with age, particularly in adults older than 65 years, and it is associated with a number of adverse health outcomes (AHO), particularly hospitalizations, falls and mortalities. Given that approximately one-third of these anemias are due to reversible causes, we studied whether the treatment of nutritional deficiency anemia (NDA), namely iron deficiency anemia (IDA), cobalamin deficiency anemia (CDA), and folate deficiency anemia (FDA), improves AHO; and explored whether each NDA had different AHO.

Methods

We reviewed electronic medical records of our internal medicine office patients aged 65 years or older, who had a diagnosis of anemia in a non-acute setting.

Results

Total 600 patients were included. Mean age was 75.2 years. Thirty-one point three percent had NDA (CDA 15.3%, IDA 12.3%, FDA 3.7%); and 68.7% had other anemias whom we categorized as non-nutritional deficiency anemias (NNDA), which included anemia of chronic disease (11.2%), myelodysplastic syndrome (6.2%), renal insufficiency anemia (5.7%) and unexplained anemia (45.6%). Even after adequate treatment, IDA group had significantly more hospitalizations (median, 25th - 75th: 2 (0 - 4) vs. 0 (0 - 1), P < 0.001), falls (median, 25th - 75th: 1 (0 - 3) vs. 0 (0 - 1), P < 0.001) and mortalities (10.8% vs. 3.4%, P = 0.011); CDA group had significantly more hospitalizations (median, 25th - 75th: 1 (0 - 2) vs. 0 (0 - 1), P = 0.007), but no difference in falls (median, 25th - 75th: 0 (0 - 1) vs. 0 (0 - 1), P = 0.171) and mortalities (7.6% vs. 3.4%, P = 0.083); and FDA group had significantly more hospitalizations (median, 25th - 75th: 1 (0 - 2) vs. 0 (0 - 1), P = 0.001), but no difference in falls (median, 25th - 75th: 0 (0 - 1) vs. 0 (0 - 1), P = 0.615) and mortalities (4.5% vs. 3.4%, P = 0.550), compared to the NNDA group. Age, Black race, higher number of comorbidities, presence of malignancy and use of direct oral anticoagulants were associated with increased odds of AHO in patients with NDA.

Conclusions

Compared to the patients with NNDA, patients with IDA had more hospitalizations, falls and mortalities even after adequate treatment; while patients with CDA and FDA had only more hospitalizations. Adequate treatment mitigated falls and mortalities in elderly patients with CDA and FDA.

Higher gastric parietal cell antibody titer significantly increases the frequencies of macrocytosis, serum vitamin B12 deficiency, and hyperhomocysteinemia in patients with burning mouth syndrome

BACKGROUND/PURPOSE

Our previous study found 109 gastric parietal cell antibody (GPCA)-positive burning mouth syndrome (BMS) patients (so-called GPCA⁺BMS patients in this study) in a group of 884 BMS patients. This study evaluated whether high-titer (GPCA titer ≥ 160) GPCA⁺BMS patients had greater frequencies of macrocytosis, anemia, serum iron and vitamin B12 deficiencies, and hyperhomocysteinemia than low-titer (GPCA titer < 160) GPCA⁺BMS patients or 442 healthy control subjects.

MATERIALS AND METHODS

Complete blood count, serum iron, vitamin B12, folic acid, homocysteine, and GPCA levels in 42 high-titer GPCA⁺BMS patients, 67 low-titer GPCA⁺BMS patients, and 442 healthy control subjects were measured and compared.

RESULTS

We found that 33.3%, 38.1%, 19.0%, 33.3%, 2.4%, and 57.1% of 42 high-titer GPCA⁺BMS patients and 10.4%, 25.4%, 14.9%, 6.0%, 1.5%, and 11.9% of 67 low-titer GPCA⁺BMS patients were diagnosed as having macrocytosis, blood hemoglobin, iron, vitamin B12, and folic acid deficiencies, and hyperhomocysteinemia, respectively. Moreover, both 42 high-titer and 67 low-titer GPCA⁺BMS patients had significantly greater frequencies of macrocytosis, blood hemoglobin, serum iron and vitamin B12 deficiencies, and hyperhomocysteinemia than 442 healthy control subjects (all P-values < 0.001). In addition, 42 high-titer GPCA⁺BMS patients also had greater frequencies of macrocytosis, serum vitamin B12 deficiency, and hyperhomocysteinemia than 67 low-titer GPCA⁺BMS patients (all P-values < 0.01).

CONCLUSION

The high-titer GPCA⁺BMS patients have significantly greater frequencies of macrocytosis, anemia, serum iron and vitamin B12 deficiencies, and hyperhomocysteinemia than healthy control subjects and significantly greater frequencies of macrocytosis, serum vitamin B12 deficiency, and hyperhomocysteinemia than low-titer GPCA⁺BMS patients.

Anemia, hematinic deficiencies, hyperhomocysteinemia, and gastric parietal cell antibody positivity in burning mouth syndrome patients with normocytosis

Background/Purpose

Normocytosis is defined as having the mean corpuscular volume (MCV) between 80 fL and 99.9 fL. This study evaluated whether 770 burning mouth syndrome (BMS) patients with normocytosis (so-called normocytosis/BMS patients) had significantly higher frequencies of anemia, hematinic deficiencies, hyperhomocysteinemia, and serum gastric parietal cell antibody (GPCA) positivity than 442 healthy control subjects or 884 BMS patients.

Materials and methods

Complete blood count, serum iron, vitamin B12, folic acid, homocysteine, and GPCA levels in 884 BMS patients (including 770 normocytosis/BMS patients) and 442 healthy control subjects were measured and compared.

Results

We found that 12.3%, 13.2%, 2.2%, 2.3%, 17.3%, and 10.5% of 770 normocytosis/BMS patients had blood hemoglobin (Hb), iron, vitamin B12, and folic acid deficiencies, hyperhomocysteinemia, and serum GPCA positivity, respectively. Furthermore, 770 normocytosis/BMS patients had significantly higher frequencies of blood Hb, iron, vitamin B12, and folic acid deficiencies, hyperhomocysteinemia, and serum GPCA positivity than 442 healthy control subjects (all P-values < 0.005). On the contrary, 770 normocytosis/BMS patients had significantly lower frequencies of blood Hb and vitamin B12 deficiencies than overall 884 BMS patients (both P-values < 0.01).

Conclusion

We conclude that there are significantly higher frequencies of anemia, serum iron, vitamin B12, and folic acid deficiencies, hyperhomocysteinemia, and serum GPCA positivity in normocytosis/BMS patients than in healthy control subjects. On the contrary, normocytosis/BMS patients do have significantly lower frequencies of blood Hb and vitamin B12 deficiencies than overall BMS patients.

Prevalence of Vitamin B12 deficiency in elderly population (>60 years) presenting with dementia to outpatient department

BACKGROUND

Vitamin B12 deficiency is an easily treatable cause of reversible dementia. It is likely to be more common in Indian population due to traditionally vegetarian culture. This study was conducted to estimate the prevalence of Vitamin B12 deficiency in elderly patients (>60 years) with dementia attending outpatient department.

METHODS

This study was conducted in two phases. The first phase was a cross sectional observational study to estimate the prevalence of Vitamin B12 deficiency in the elderly population with dementia. The second phase was a pilot study done in subjects with Vitamin B12 deficiency to assess the change in cognition following Vitamin B12 supplementation.

RESULTS

Out of 2920 study eligible subjects, 200 were diagnosed as dementia with Mini Mental Status Examination (MMSE) score of ≤ 24. Vitamin B12 deficiency was seen in 7.5% of patients. Vitamin B12 deficiency was associated with shorter and more severe dementia. Macrocytosis was more common in Vitamin B12 deficiency (p value < 0.001) where as vegetarian diet did not show significant correlation (p value 0.69). There was significant improvement in the median MMSE score in the intervention group with increase in MMSE by 2 points at 6-8 weeks and 3 points at 12 weeks (p value 0.009 and 0.003 by Mann Whitney test).

CONCLUSION

Prevalence of Vitamin B12 deficiency in dementia was 7.5%. It was associated with macrocytosis, shorter duration and more severe dementia. There was a significant improvement in median MMSE score at 6 weeks and 12 weeks following Vitamin B12 supplementation.

Reference intervals for plasma vitamin B12 and plasma/serum methylmalonic acid in Danish children, adults and elderly

BACKGROUND

Plasma/serum vitamin B12 (B12) is often used to screen for B12 deficiency complemented with analysis of methylmalonic acid (MMA) in case of low B12. The concentration of both analytes likely depends on age, and we, therefore, aimed at establishing 95% age-adjusted reference intervals (RIs) for plasma B12 and serum/plasma MMA in the Danish population.

METHODS

We collected and analysed blood samples from healthy children, adults, and elderly individuals and extracted routine clinical B12 and MMA results to establish RIs. We also evaluated the association between matching B12 and MMA results.

RESULTS

We suggest the following RIs for plasma B12 and plasma/serum MMA, respectively. 0-<1 year: 180-1400 pmol/L, 0.10-1.25 µmol/L; 1-<11 years: 260-1200 pmol/L, 0.10-0.30 µmol/L; 12-<18 years: 200-800 pmol/L, 0.10-0.35 µmol/L; 18-<65 years: 200-600 pmol/L, 0.10-0.40 µmol/L; 65 + years: 200-600 pmol/L, 0.12-0.46 µmol/L. Finally, the proportion of patients with elevated MMA differed between age groups independently of B12 and was highest in children.

CONCLUSION

We propose new age-adjusted RIs for B12 and MMA and suggest that age-dependent cut-off values should be implemented if plasma B12 is used to screen for B12 deficiency.

The dangers of recreational inhalation of nitrous oxide

Nitrous oxide, also known as 'laughing gas', is one of the most widely used recreational drugs among teenagers in the UK. Copious inhalation of nitrous oxide may increase intra-alveolar pressure, resulting in barotrauma secondary to alveolar rupture. Pneumomediastinum and subcutaneous emphysema are common clinical findings in nitrous oxide-associated barotrauma. Prolonged nitrous oxide misuse may inactivate vitamin B₁₂ through the alteration of its metabolism, causing demyelination of the central and peripheral nervous system. A spectrum of neurological manifestations has been reported, including peripheral neuropathy, myelopathy and subacute combined degeneration of the spinal cord. Medical therapies and psychosocial interventions aiming at nitrous oxide cessation are important treatment steps to achieve partial or complete recovery from the adverse effects associated with inhalation of nitrous oxide.

Acute cerebellar ataxia as the first manifestation of Imerslund-Gräsbeck syndrome

Imerslund-Gräsbeck syndrome is a rare condition caused by vitamin B12 deficiency and proteinuria. In this article, we reported the case of a 10-year-old girl with imbalance and urinary incontinence. The case had cerebellar ataxia as the primary manifestation. The disequilibrium had progressed gradually within three weeks and was consistent with the symptoms of cerebellar involvement and urinary incontinence. Brain and cervico-thoraco-lumbar magnetic resonance imaging were normal. The patient had elevated lactate dehydrogenase (LDH=4775), in addition to macrocytic anemia, on laboratory examinations; thus, the possibility of malignancy was raised. Then, bone marrow aspiration was performed, showing hypercellular marrow with megaloblastic changes. This finding proved megaloblastic anemia. Regarding the low prevalence of vitamin B12 deficiency in healthy individuals, extensive studies were performed to find out the cause. The serum level of vitamin B12 was found to be lower than the normal range. Although urinalysis revealed significant proteinuria, further nephrological investigations did not indicate any abnormalities. No evidence of serious problems was observed in the gastrointestinal tract study, and metabolic studies were normal. Finally, based on the obtained data, Imerslund-Gräsbeck syndrome was recognized. Patient was treated by vitamin B12 injection, leading to improved balance, and in one-month follow-up, she was able to walk independently, and the cerebellar symptoms had greatly disappeared; however, proteinuria persisted.

Prevalence and Disparities in Folate and Vitamin B12 Deficiency Among Preschool Children in Guatemala

BACKGROUND AND OBJECTIVE

Folate and vitamin B12 deficiencies can impair proper growth and brain development in children. Data on the folate and vitamin B12 status of children aged 6-59 months in Guatemala are scarce. Identification of factors associated with higher prevalence of these micronutrient deficiencies within the population is needed for national and regional policymakers.

OBJECTIVE

To describe national and regional post-fortification folate and vitamin B12 status of children aged 6-59 months in Guatemala.

METHODS

A multistage, cluster probability study was carried out with national and regional representation of children aged 6-59 months. Demographic and health information was collected for 1246 preschool children, but blood samples for red blood cell (RBC) folate and vitamin B12 were collected and analyzed for 1,245 and 1143 preschool children, respectively. We used the following deficiency criteria as cutoff points for the analyses: < 305 nmol/L for RBC folate, < 148 pmol/L for vitamin B12 deficiency, and 148-221 pmol/L for marginal vitamin B12 deficiency. Prevalence of RBC folate deficiency and vitamin B12 deficiency and marginal deficiency were estimated. Prevalence risk ratios of RBC folate and vitamin B12 deficiency were estimated comparing subpopulations of interest.

RESULTS

The national prevalence estimates of RBC folate deficiency among children was 33.5% [95% CI 29.1, 38.3]. The prevalence of RBC folate deficiency showed wide variation by age (20.3-46.6%) and was significantly higher among children 6-11 months and 12-23 months (46.6 and 37.0%, respectively), compared to older children aged 48-59 months (20.3%). RBC folate deficiency also varied widely by household wealth index (22.6-42.0%) and geographic region (27.2-46.7%) though the differences were not statistically significant. The national geometric mean for RBC folate concentrations was 354.2 nmol/L. The national prevalences of vitamin B12 deficiency and marginal deficiency among children were 22.5% [95% CI 18.2, 27.5] and 27.5% [95% CI 23.7, 31.7], respectively. The prevalence of vitamin B12 deficiency was significantly higher among indigenous children than among non-indigenous children (34.5% vs. 13.1%, aPRR 2.1 95% CI 1.4, 3.0). The prevalence of vitamin B12 deficiency also significantly varied between the highest and lowest household wealth index (34.3 and 6.0%, respectively). The national geometric mean for vitamin B12 concentrations was 235.1 pmol/L. The geometric means of folate and B12 concentrations were significantly lower among children who were younger, had a lower household wealth index, and were indigenous (for vitamin B12 only). Folate and vitamin B12 concentrations showed wide variation by region (not statistically significant), and the Petén and Norte regions showed the lowest RBC folate and vitamin B12 concentrations, respectively.

CONCLUSIONS

In this study, a third of all children had RBC folate deficiency and half were vitamin B12 deficient. Folate deficiency was more common in younger children and vitamin B12 deficiency was more common in indigenous children and those from the poorest families. These findings suggest gaps in the coverage of fortification and the need for additional implementation strategies to address these gaps in coverage to help safeguard the health of Guatemalan children.

Association of vitamin B12 deficiency with metformin use in patients with type 2 diabetes treated in the largest tertiary care hospital in Qatar

BACKGROUND

Data on the effect of metformin on serum vitamin B12 (VitB12) level in patients with type 2 diabetes mellitus (T2DM) in Qatar are limited; therefore, we aimed to assess the prevalence of VitB12 deficiency and its related factors among patients with tbl2DM treated with metformin at Hamad General Hospital in Doha, Qatar, from January 1, 2017, to December 31, 2017.

METHODS

This cross-sectional analytical study involved patients with tbl2DM aged ≥ 18 years who used metformin for at least 3 months. The serum VitB12 was quantified on a chemiluminescent enzyme immunoassay analyzer using Cobas e 801 module, Roche, and VitB12 deficiency was defined as serum VitB12 level of ≤ 145 pmol/L. All data were obtained from the patients' electronic medical records.

RESULTS

The study recruited 3124 eligible patients with tbl2DM. The overall prevalence of metformin-associated VitB12 deficiency was 30.7% [95% confidence of interval, 0.290-0.323]. A significant difference exists in the median VitB12 levels between the VitB12-normal and VitB12-deficient groups [129 vs. 286; p < 0.001]. Compared with the VitB12-normal group, the VitB12-deficient group had higher mean body mass index (BMI) (p < 0.001) and consumed higher doses of metformin (p = 0.001). They also more often used sulfonylurea (p = 0.004), dipeptidyl peptidase-4 inhibitor (p < 0.001), thiazolidinediones (p < 0.001), glucagon-like peptide 1 [GLP-1] receptor agonists (p < 0.001), alpha-glucosidase inhibitor (p < 0.001), and H2 blocker/proton pump inhibitors [PPI] (p < 0.001) than the VitB12-normal group. Moreover, the VitB12-normal group consumed more calcium supplements (p < 0.001) than the VitB12-deficient group. In the multivariate analysis, independent risk factors for metformin-associated VitB12 deficiency in patients with tbl2DM include high daily dose of metformin >2000 mg, male gender, high BMI, smoking, sulfonylurea, dipeptidyl peptidase-4 inhibitor, H2 blockers/PPI, low fasting blood glucose, and low hemoglobin.

CONCLUSION

This study showed a high prevalence of VitB12 deficiency in patients with tbl2DM taking metformin and a significant negative correlation between the daily dose of metformin and serum VitB12 level. Therefore, regular screening for serum VitB12 is necessary in patients with tbl2DM on metformin treatment, especially those who have the abovementioned risk factors.

Improvement in vitamin B12 status of Wistar rats by supplementing the diet with Chlorella vulgaris biomass

The sources of bioavailable vitamin B₁₂ are limited, and most of them are animal-derived. Chlorella vulgaris, a freshwater microalga, is known for immune system boosting, nutraceutical properties and presence of a natural form of vitamin B₁₂. The present study focused on the in vivo evaluation of the Chlorella biomass as a source of bioavailable vitamin B₁₂ to alleviate the vitamin B₁₂ deficiency status of Wistar rats. Experimental animals were evaluated for the vitamin B₁₂ deficiency-related circulatory marker (serum vitamin B₁₂) and functional markers (plasma homocysteine and urinary methylmalonic acid), haematological and histological changes. The results showed that an increase of 2.4-fold in urinary methylmalonic acid (13.01 ± 0.89 µmoles moles of creatinine^-1), 2.6-fold in plasma homocysteine (17.18 ± 3.57 µmole L^-1), and 48% decrease in serum vitamin B₁₂ levels (252.69 ± 1.46 pg mL^-1) in vitamin B₁₂ deficient group compared to control animals. The Chlorella biomass supplementation in the diet led to the restoration of the functional and circulatory markers, hematological parameters, and vitamin B₁₂ content of kidney and liver to control levels. The Chlorella biomass supplementation increased the erythrocyte precursors and MAST cells in the bone marrow and also normalized the histological features of kidney, liver, and lung tissues. The results suggest that the vitamin B₁₂ from the Chlorella biomass was bioavailable and facilitated the improvement of vitamin B₁₂ status in deficient rats.

Severe Vitamin B12 Deficiency Mimicking Microangiopathic Hemolytic Anemia

Most individuals with vitamin B12 deficiency present with anemia, fatigue, and neurologic disturbances such as paresthesia and loss of sensory function if chronic. However, in severe states, it may manifest as hemolytic anemia, thrombocytopenia, schistocytosis, elevated lactate dehydrogenase, and low reticulocyte production. This phenomenon is known as pseudo-thrombotic microangiopathy (TMA), and is most commonly due to pernicious anemia. The overlap in clinical presentation with primary TMA creates a challenge in the diagnosis and management of pseudo-TMA. Primary TMA, particularly thrombotic thrombocytopenic purpura, is emergently managed with plasma exchange and may require admission to an intensive care unit due to high risk of mortality. In contrast, pseudo-TMA does not respond to plasma exchange and instead is treated with vitamin B12 supplementation. Patients with this atypical presentation of B12 deficiency may receive unnecessary, costly, and potentially harmful therapy. We present the case of a patient with pseudo-TMA in the setting of pernicious anemia.

Anemia, hematinic deficiencies, hyperhomocysteinemia, and gastric parietal cell antibody positivity in burning mouth syndrome patients with macrocytosis

Background/purpose

Macrocytosis is defined as having the mean corpuscular volume (MCV) ≥ 100 fL. This study evaluated whether 46 burning mouth syndrome (BMS) patients with macrocytosis had significantly higher frequencies of anemia, hematinic deficiencies, hyperhomocysteinemia, and serum gastric parietal cell antibody (GPCA) positivity than 442 healthy control subjects or 884 BMS patients.

Materials and methods

Complete blood count, serum iron, vitamin B12, folic acid, homocysteine, and GPCA levels in 46 BMS patients with macrocytosis, 884 BMS patients, and 442 healthy control subjects were measured and compared.

Results

We found that 65.2%, 23.9%, 47.8%, 0.0%, 60.9%, and 45.7% of 46 BMS patients with macrocytosis were diagnosed as having blood hemoglobin, iron, vitamin B12, and folic acid deficiencies, hyperhomocysteinemia, and serum GPCA positivity, respectively. Moreover, 46 BMS patients with macrocytosis had significantly higher frequencies of blood hemoglobin and serum vitamin B12 deficiencies, hyperhomocysteinemia, and serum GPCA positivity than 442 healthy control subjects or 884 BMS patients (all P-values < 0.001). In addition, 46 BMS patients with macrocytosis also had a significantly higher frequency of serum iron deficiency than 442 healthy control subjects (P < 0.001). Pernicious anemia was found in 15 BMS patients with macrocytosis.

Conclusion

There are significantly higher frequencies of anemia and serum iron and vitamin B12 deficiencies, hyperhomocysteinemia, and serum GPCA positivity in BMS patients with macrocytosis than in healthy control subjects. BMS patients with macrocytosis also have significantly higher frequencies of anemia, serum vitamin B12 deficiency, hyperhomocysteinemia, and serum GPCA positivity than BMS patients.

Anemia, hematinic deficiencies, and hyperhomocysteinemia in serum gastric parietal cell antibody-positive burning mouth syndrome patients without serum thyroid autoantibodies

Background/purpose

Our previous study found that 70 of 884 burning mouth syndrome (BMS) patients have serum gastric parietal cell antibody (GPCA) positivity but without thyroglobulin antibody (TGA) and thyroid microsomal antibody (TMA) (so-called GPCA⁺TGAˉTMAˉBMS patients). This study assessed whether these 70 GPCA⁺TGAˉTMAˉBMS patients had significantly higher frequencies of macrocytosis, anemia, hematinic deficiencies, and hyperhomocysteinemia than 553 GPCA-negative, TGA-negative, and TMA-negative BMS (GPCAˉTGAˉTMAˉBMS) patients or 442 healthy control subjects.

Materials and methods

Complete blood count, serum iron, vitamin B12, folic acid, homocysteine, GPCA, TGA, and TMA levels in 70 GPCA⁺TGAˉTMAˉBMS patients, 553 GPCAˉTGAˉTMAˉBMS patients, and 442 healthy control subjects were measured and compared.

Results

We found that 15.7%, 28.6%, 20.0%, 11.4%, 2.9%, and 25.7% of 70 GPCA⁺TGAˉTMAˉBMS patients and 3.8%, 17.7%, 15.9%, 3.8%, 2.7%, and 20.1% of 553 GPCAˉTGAˉTMAˉBMS patients had macrocytosis, blood hemoglobin, iron, vitamin B12, and folic acid deficiencies, and hyperhomocysteinemia, respectively. Moreover, both 70 GPCA⁺TGAˉTMAˉBMS patients and 553 GPCAˉTGAˉTMAˉBMS patients had significantly greater frequencies of macrocytosis, blood hemoglobin, serum iron, vitamin B12, and folic acid deficiencies, and hyperhomocysteinemia than 442 healthy control subjects (all P-values < 0.05). In addition, 70 GPCA⁺TGAˉTMAˉBMS patients also had greater frequencies of macrocytosis, anemia, serum vitamin B12 deficiency, and hyperhomocysteinemia than 553 GPCAˉTGAˉTMAˉBMS patients (all P-values < 0.05).

Conclusion

The GPCA ⁺ TGAˉTMAˉBMS patients have significantly greater frequencies of macrocytosis, anemia, serum iron, vitamin B12, and folic acid deficiencies, and hyperhomocysteinemia than healthy control subjects and significantly greater frequencies of macrocytosis, anemia, serum vitamin B12 deficiency, and hyperhomocysteinemia than GPCAˉTGAˉTMAˉBMS patients.

Etiological causes of pancytopenia: A report of 137 cases

OBJECTIVE

The aim of this study is to evaluate the etiological causes of pancytopenia in patients who were admitted to the hematology ward due to pancytopenia.

MATERIALS AND METHODS

All patients who were admitted to the hematology ward of Ministry of Health Istanbul Training and Research Hospital due to pancytopenia between 2013 and 2015 were retrospectively evaluated regarding etiological causes.

RESULTS

A total of 137 patients was evaluated. The etiological causes of pancytopenia were recorded as Vitamin B12 deficiency (n: 24; 17%), chronic liver disease (n: 21; 15%), malignancy (n: 19; 13%), myelodysplastic syndrome (n: 18; 13%), aplastic anemia (n: 11; 8%), rheumatic diseases (n: 7; 5%), and endocrine causes (n: 3; 2%).

CONCLUSION

The etiological causes of pancytopenia vary depends on patients' age, gender, country, and other conditions. Vitamin B12 deficiency is the most common treatable cause of pancytopenia. Most of the etiological causes could be diagnosed with laboratory analysis and radiological imagings, without the need of a bone marrow examination.

Long-term metformin therapy and vitamin B12 deficiency: An association to bear in mind

To date, metformin remains the first-line oral glucose-lowering drug used for the treatment of type 2 diabetes thanks to its well-established long-term safety and efficacy profile. Indeed, metformin is the most widely used oral insulin-sensitizing agent, being prescribed to more than 100 million people worldwide, including patients with prediabetes, insulin resistance, and polycystic ovary syndrome. However, over the last decades several observational studies and meta-analyses have reported a significant association between long-term metformin therapy and an increased prevalence of vitamin B12 deficiency. Of note, evidence suggests that long-term and high-dose metformin therapy impairs vitamin B12 status. Vitamin B12 (also referred to as cobalamin) is a water-soluble vitamin that is mainly obtained from animal-sourced foods. At the cellular level, vitamin B12 acts as a cofactor for enzymes that play a critical role in DNA synthesis and neuroprotection. Thus, vitamin B12 deficiency can lead to a number of clinical consequences that include hematologic abnormalities (e.g., megaloblastic anemia and formation of hypersegmented neutrophils), progressive axonal demyelination and peripheral neuropathy. Nevertheless, no definite guidelines are currently available for vitamin B12 deficiency screening in patients on metformin therapy, and vitamin B12 deficiency remains frequently unrecognized in such individuals. Therefore, in this "field of vision" article we propose a list of criteria for a cost-effective vitamin B12 deficiency screening in metformin-treated patients, which could serve as a practical guide for identifying individuals at high risk for this condition. Moreover, we discuss additional relevant topics related to this field, including: (1) The lack of consensus about the exact definition of vitamin B12 deficiency; (2) The definition of reliable biomarkers of vitamin B12 status; (3) Causes of vitamin B12 deficiency other than metformin therapy that should be identified promptly in metformin-treated patients for a proper differential diagnosis; and (4) Potential pathophysiological mechanisms underlying metformin-induced vitamin B12 deficiency. Finally, we briefly review basic concepts related to vitamin B12 supplementation for the treatment of vitamin B12 deficiency, particularly when this condition is induced by metformin.