Ascorbic acid deficiency amongst spondylodiscitis patients.

BACKGROUND: Spondylodiscitis can be a disabling and life-threatening infection. Ascorbic Acid is crucial for neutrophil function and collagen formation. Its association and clinical relevance in spondylodiscitis has not been previously examined. AIMS: To determine the prevalence, characteristics, and clinical outcomes of spondylodiscitis patients with Ascorbic Acid deficiency. METHODS: Sixty-eight consecutive patients admitted with spondylodiscitis, between December 2021 and August 2023 were included. Clinical characteristics, Ascorbic Acid levels and clinical outcomes were evaluated. RESULTS: Thirty-seven patients had Ascorbic Acid levels taken during admission. The median initial Ascorbic Acid level was 15 µmol/L with an IQR 6.5-27 µmol/L. Depletion defined as <28 µmol/L was present in 78% of patients. Deficiency defined as ≤11 µmol/L was present in and 46% of patients. Patients with depletion were more likely to require Intensive Care Admission (absolute risk increase = 24.1%; 2.6%-45.7%). Fifteen patients had repeat serum levels taken during admission with median increase of 17 µmol/L and an IQR 0-26 µmol/L. Patients that received supplementation had a significantly greater increase in Ascorbic Acid levels compared with those that did not receive supplementation (P = 0.002). CONCLUSION: Ascorbic acid deficiency is highly prevalent amongst spondylodiscitis patients. Depletion was associated with worse outcomes. Replacement significantly increased serum levels in comparison to standard hospital diet. The clinical significance of replacement remains to be evaluated.

Interleukin-8 and neutrophil extracellular traps in children with lupus nephritis and vitamin C deficiency.

BACKGROUND: Vitamin C is a potent scavenger of reactive oxygen species, which induce neutrophil extracellular trap (NET) formation. NETs are a major source of autoantigens and are involved in systemic lupus erythematosus (SLE) pathogenesis. We determined vitamin C status and evaluated NET formation and inflammatory cytokines in children with lupus nephritis. METHODS: Serum vitamin C was measured in 46 patients (82.6% females, mean age 14.5 ± 0.3 years). Vitamin C levels < 0.3 mg/dL indicated vitamin C deficiency. Patients were divided into two groups according to serum vitamin C levels: normal and low (< 0.3 mg/dL). We compared NET formation and levels of SLE-related cytokines, including interleukin (IL)-8, IL-10, and tumor necrosis factor-α (TNF-α), between groups. NET formation was determined through measurement of serum citrullinated histone 3 levels and mRNA expression of peptidyl arginine deiminase-4 and assessment of the percentage of neutrophils with NETs by immunofluorescence. RESULTS: Nine patients (19.6%) had vitamin C deficiency. Kidney pathology assessment at disease onset revealed that histological activity index and number of kidney biopsies containing crescentic glomeruli were higher in vitamin C-deficient patients, but chronicity index was not. NET formation and serum IL-8 were more prominent in vitamin C-deficient patients. Serum IL-8 levels were 12.9 ± 5.2 pg/mL in low vitamin C group and 5.2 ± 0.9 pg/mL in normal vitamin C group (p = 0.03). Serum IL-10 and TNF-α were similar between groups. CONCLUSIONS: Our study demonstrated correlation among vitamin C deficiency, increased NET formation, and IL-8 upregulation in children with lupus nephritis. A prospective study is required to evaluate cause‒effect relationships of vitamin C status, NET formation and IL-8 expression.

Risk of Hypovitaminosis and Vitamin C Deficiency in Pediatric Patients Undergoing Cardiopulmonary Bypass.

Vitamin C levels are known rapidly decrease in adult critical illness. Vitamin C scavenges free radicals, provides critical protection of the endothelial barrier, and improves endothelial responsiveness to catecholamines. Children with congenital heart disease and undergoing cardiac surgery might be at increased risk for low circulating vitamin C levels. A prospective single-center observational study investigated perioperative changes in vitamin C levels in critically ill Children who underwent congenital heart surgery using CPB. Vitamin C serum levels were collected preoperatively and postoperatively (upon admission to the ICU, 24 and 72 h). Linear mixed-effect model was used to estimate mean circulating concentration of vitamin C and to estimate changes in concentration over time. Primary outcome was change in circulating levels of vitamin C before and after CPB. Secondary outcomes were hospital length of stay (LOS), acute kidney injury (AKI), and illness severity. Forty-one patients with a median age of 4.5 [interquartile range (IQR) 2.6-65.6] months at the time of surgery were consented and enrolled. Median CPB duration was 130 [90-175] minutes, and hospital LOS was 9.1 [5.2-19] days. Mean vitamin C levels (µmol/L) before CPB, at PICU admission, 24 h, and 72 h were 82.0 (95% CI 73.4-90.7), 53.4 (95% CI 44.6,62.0), 55.1 (95% CI 46.3,63.8), and 59.2 (95% CI 50.3,68.1), respectively. Upon postoperative admission to the PICU, vitamin C levels decreased by 28.7 (95% CI 20.6-36.8; p < 0.001) µmol/L, whereas levels at 24 and 72 h recovered and did not differ substantially from concentrations reported upon PICU admission (p > 0.15). Changes in vitamin C concentration were not associated with CPB time, STAT mortality category, age, or PIM3. Three patients had post-CPB hypovitaminosis C or vitamin C deficiency. Reduction in vitamin C levels was not associated with hospital LOS (p = 0.673). A 25 µmol/L decrease in vitamin C levels upon PICU admission was associated with developing AKI (aOR = 3.65; 95% CI 1.01-18.0, p = 0.049). Pediatric patients undergoing cardiac surgery with CPB showed decreased vitamin C levels during the immediate postoperative period. Effects of hypovitaminosis C and vitamin C deficiency in this population remain unclear.

Vitamin C Urinary Loss and Deficiency in Human Immunodeficiency Virus (HIV): Cross-sectional Study of Vitamin C Renal Leak in Women With HIV.

BACKGROUND: Reduced plasma vitamin C (vitC) concentrations in human immunodeficiency virus (HIV) may result from abnormal urinary excretion: a renal leak. VitC renal leak indicates underlying nutritional dysregulation independent of diet. We hypothesized that increased renal leak prevalence in HIV would be associated with deficient vitC concentrations. METHODS: We conducted an outpatient cross-sectional study of 96 women (40 HIV [PWH] and 56 without HIV [PWOH]) at the National Institutes of Health and Georgetown University. Renal leak was defined as abnormal urinary vitC excretion at fasting plasma concentrations <43.2µM, 2 SDs below vitC renal threshold in healthy women. To determine the primary outcome of renal leak prevalence, matched urine and plasma samples were collected the morning after overnight fast. Secondary outcomes assessed group differences in mean plasma vitC concentrations and prevalence of vitC deficiency. Exploratory outcomes assessed clinical parameters associated with renal leak. VitC was measured by high-performance liquid chromatography with coulometric electrochemical detection. RESULTS: PWH had significantly higher renal leak prevalence (73%vs14%; OR (odds ratio):16; P<.001), lower mean plasma vitC concentrations (14µMvs50µM; P<.001), and higher prevalence of vitC deficiency (43%vs7%; OR:10; P<.001) compared with PWOH, unchanged by adjustments for confounding factors. Significant predictors of renal leak included antiretroviral therapy (ART), Black race, older age, and metabolic comorbidities but not viral load or CD4 count. When compared with other chronic disease cohorts, PWH had the highest prevalence of renal leak and vitC deficiency (P<.001). CONCLUSIONS: High prevalence of vitC renal leak in HIV was associated with vitC deficiency, ART use, and race/ethnicity differences.

The Role of Vitamin C and Vitamin D in the Pathogenesis and Therapy of Periodontitis-Narrative Review.

Periodontitis is a common disorder affecting the bone and soft tissues of the periodontal complex. When untreated, it may lead to severe mobility or even loss of teeth. The pathogenesis of periodontitis is complex, with crucial factors being chronic inflammation in gingival and periodontal tissues and oral microbiome alterations. However, recent studies highlight the alleged role of vitamins, such as vitamin C (VitC) and vitamin D (VitD), in the development of the disease. VitC regulates numerous biochemical reactions, but foremost, it is involved in synthesizing collagen. It was reported that VitC deficiency could lead to damage to the periodontal ligaments. VitC supplementation improves postoperative outcomes in patients with periodontitis. VitD is a steroid derivative that can be produced in the skin under ultraviolet radiation and later transformed into an active form in other tissues, such as the kidneys. VitD was established to decrease the expression of proinflammatory cytokines in gingiva and regulate the proper mineral density of teeth. Moreover, the supplementation of VitD was associated with better results in the nonsurgical treatment of periodontitis. In this review, we summarize recent knowledge on the role of vitamins C and D in the pathogenesis and treatment of periodontitis.

What We Are Missing: Using Machine Learning Models to Predict Vitamin C Deficiency in Patients with Metabolic and Bariatric Surgery.

PURPOSE: Vitamin C (VC) is implicated in many physiological pathways. Vitamin C deficiency (VCD) can compromise the health of patients with metabolic and bariatric surgery (patients). As symptoms of VCD are elusive and data on VCD in patients is scarce, we aim to characterize patients with measured VC levels, investigate the association of VCD with other lab abnormalities, and create predictive models of VCD using machine learning (ML). METHODS: A retrospective chart review of patients seen from 2017 to 2021 at a tertiary care center in Northeastern USA was conducted. A 1:4 case mix of patients with VC measured to a random sample of patients without VC measured was created for comparative purposes. ML models (BayesNet and random forest) were used to create predictive models and estimate the prevalence of VCD patients. RESULTS: Of 5946 patients reviewed, 187 (3.1%) had VC measures, and 73 (39%) of these patients had VC<23 µmol/L(VCD. When comparing patients with VCD to patients without VCD, the ML algorithms identified a higher risk of VCD in patients deficient in vitamin B1, D, calcium, potassium, iron, and blood indices. ML models reached 70% accuracy. Applied to the testing sample, a "true" VCD prevalence of ~20% was predicted, among whom ~33% had scurvy levels (VC<11 µmol/L). CONCLUSION: Our models suggest a much higher level of patients have VCD than is reflected in the literature. This indicates a high proportion of patients remain potentially undiagnosed for VCD and are thus at risk for postoperative morbidity and mortality.

Clinical and molecular characteristics associated with Vitamin C deficiency in myeloid malignancies; real world data from a prospective cohort.

Vitamin C is an essential vitamin that acts as a co-factor for many enzymes involved in epigenetic regulation in humans. Low vitamin C levels in hematopoietic stem cells (HSC) promote self-renewal and vitamin C supplementation retards leukaemogenesis in vitamin C-deficient mouse models. Studies on vitamin C levels in patients with myeloid malignancies are limited. We thus conducted a retrospective analysis on a prospective cohort of patients with myeloid malignancies on whom plasma vitamin C levels were measured serially at diagnosis and during treatment. Baseline characteristics including hematological indices, cytogenetics, and molecular mutations are described in this cohort. Among 64 patients included in our study, 11 patients (17%) had low vitamin C levels. We noted a younger age at diagnosis for patients with myeloid malignancies who had low plasma vitamin C levels. Patients with low plasma vitamin C levels were more likely to have acute myeloid leukemia compared to other myeloid malignancies. Low vitamin C levels were associated with ASXL1 mutations. Our study calls for further multi-institutional studies to understand the relevance of low plasma vitamin C level in myeloid neoplasms, the role of vitamin C deficiency in leukemogenesis, and the potential benefit of vitamin C supplementation.

Rheumatologic manifestations with elevated levels of IL-6, IL-17A, and IL-23 in a patient with scurvy.

Symptomatic vitamin C deficiency, scurvy, is a relatively rare disease in developed countries, but it has been reported in patients with autism spectrum disorder or developmental delay who tend to have selective diets. Patients with scurvy often demonstrate musculoskeletal manifestations with unknown pathophysiology. Herein, we report a case of scurvy in an 11-year-old boy who presented with iron-deficiency anaemia, systemic osteomyelitis, myositis predominantly in the lower extremities, and right ventricular volume overload with mild pulmonary hypertension and was diagnosed with scurvy. He had a mild developmental disorder and a selective diet, which resulted in severe vitamin C deficiency. He received intravenous and oral vitamin C supplementation, which relieved his arthralgia and muscle pain in a week. Following 4 months of vitamin C supplementation, he demonstrated no abnormal manifestations on laboratory or imaging examination and recovered without sequelae. Inflammatory cytokine and chemokine evaluations demonstrated elevated levels of interleukin (IL)-6, IL-17A, and IL-23, which are associated with T-helper (Th) 17 cell activation. This study is the first to suggest the association between the inflammation seen in scurvy, rheumatic manifestations in the patient, and Th17 cell activation. Further analysis of the association between the inflammation and vitamin C supplementation may contribute to new insights for the comprehension and treatment of other inflammatory diseases, such as rheumatic diseases.

Scurvy.

Dear Editor, Scurvy is a nutritional disorder which can develop after prolonged (>1-3 months) severe vitamin C deficiency. Vitamin C is a cofactor in several enzyme reactions involved in collagen synthesis. The defect in collagen causes blood vessel fragility, poor wound healing, mucocutaneous bleedings, hair abnormalities, bone pains, and joint contractures due to periosteal and intraarticular bleeding (1,2). Risk factors for scurvy development are undernutrition, low socioeconomic status, older age, male sex, alcoholism, tobacco smoking, and severe psychiatric illnesses (1-3). The required daily intake for vitamin C is ~60 mg, and this amount of vitamin C can be found in only one medium-sized orange. For this reason, the disease is rarely encountered in developed countries and is often underrecognized by healthcare personnel. Herein, we present an illustrative case of scurvy in order to raise the awareness of this disorder. A 61-year-old Caucasian man was admitted to hospital due to fatigue, hypotension (80/50 mmHg), severe normocytic anemia (hemoglobin 76 g/L), kidney failure (estimated glomerular filtration rate of 6 mL/min/1.73m2) and mild elevation in C-reactive protein (30.9 mg/L). Prior medical history included radical cystoprostatectomy with an ileal conduit performed eight years ago due to a bladder tumor and moderate chronic kidney disease with recurrent urinary tract infections. The patient was also an alcoholic and tobacco smoker, with a very low-income and a poor diet. He did not use any medications. Heteroanamnestically, the current clinical state had developed slowly over several weeks. At admission, the patient was afebrile, lethargic, malnourished, and immobile due to generalized weakness, bone pains, and hip and knee contractures. He had generalized edema, mostly related to kidney failure, as well as severe hypoalbuminemia (serum albumin 19 g/L). There were multiple ecchymoses (Figure 1, a) and perifollicular bleedings (Figure 1, b) in the skin. The teeth were defective, and the patient's facial hair had a "corkscrew" appearance (Figure 1, c). The platelet count was normal, as was the serum fibrinogen level and the prothrombin- and activated partial thromboplastin times. Vancomycin-resistant Enterococcus faecium and multi-drug-resistant Acinetobacter baumanii were isolated from the urine. Therefore, hemodialysis, linezolid, and colistin were started. However, the patient continued to be lethargic, immobile, and with prominent skin bleeding. Medical workup excluded the possibility of an underlying malignancy or an autoimmune disorder. Finally, scurvy was suspected and 500 mg daily of oral vitamin C was introduced into therapy. In the following two weeks, the general condition of the patient significantly improved and he was discharged from the hospital in good condition - mobile and with complete resolution of skin lesions (Figure 1, d and e). Three months later, the patient was still under maintenance hemodialysis and had mild anemia (hemoglobin 123 g/L). Interestingly, scurvy was the first disease in the history of medicine for which a randomized trial found a cure (4). The differential diagnosis of scurvy includes skin infections, hematologic disorders, collagen vascular disorders, and anticoagulant/antiplatelet side-effects (1). Pathognomonic skin findings which may help raise suspicion of scurvy are perifollicular bleedings and "corkscrew" hair. Notably, laboratory testing for vitamin C concentration is not necessary to confirm scurvy as it tends to reflect recent dietary intake of vitamin C (2). Nevertheless, it may be useful to identify less typical cases (2). In our case, rapid clinical improvement with the resolution of skin lesions and joint contractures after the introduction of vitamin C confirmed the clinical diagnosis of scurvy. Additionally, vitamin C deficiency could be, at least partly (besides kidney failure and acute infection), responsible for severe anemia at disease presentation (5). This case serves to remind clinicians not to forget scurvy when treating patients at risk for vitamin C deficiency who present with fatigue, anemia, bone pains, and unexplained mucocutaneous bleedings. In suspected cases, vitamin C should be administered without hesitation.

Prevalence and factors associated with vitamin C deficiency in inflammatory bowel disease.

BACKGROUND: Patients with inflammatory bowel disease (IBD) are prone to several nutritional deficiencies. However, data are lacking on vitamin C deficiency in Crohn's disease (CD) and ulcerative colitis (UC) patients, as well as the impact of clinical, biomarker and endoscopic disease severity on the development of vitamin C deficiency. AIM: To determine proportions and factors associated with vitamin C deficiency in CD and UC patients. METHODS: In this retrospective study, we obtained clinical, laboratory and endoscopic data from CD and UC patients presenting to the IBD clinic at a single tertiary care center from 2014 to 2019. All patients had an available plasma vitamin C level. Of 353 subjects who met initial search criteria using a cohort discovery tool, 301 ultimately met criteria for inclusion in the study. The primary aim described vitamin C deficiency (≤ 11.4 µmol/L) rates in IBD. Secondary analyses compared proportions with deficiency between active and inactive IBD. Multivariate logistic regression analysis evaluated factors associated with deficiency. RESULTS: Of 301 IBD patients, 21.6% had deficiency, including 24.4% of CD patients and 16.0% of UC patients. Patients with elevated C-reactive protein (CRP) (39.1% vs 16.9%, P < 0.001) and fecal calprotectin (50.0% vs 20.0%, P = 0.009) had significantly higher proportions of deficiency compared to those without. Penetrating disease (P = 0.03), obesity (P = 0.02) and current biologic use (P = 0.006) were also associated with deficiency on univariate analysis. On multivariate analysis, the objective inflammatory marker utilized for analysis (elevated CRP) was the only factor associated with deficiency (odds ratio = 3.1, 95% confidence interval: 1.5-6.6, P = 0.003). There was no difference in the presence of clinical symptoms of scurvy in those with vitamin C deficiency and those without. CONCLUSION: Vitamin C deficiency was common in IBD. Patients with elevated inflammatory markers and penetrating disease had higher rates of vitamin C deficiency.

A Narrative Review on Pediatric Scurvy: The Last Twenty Years.

Scurvy is a well-known clinical condition caused by vitamin C deficiency. Although considered a rare disease in high-income countries, it has been recently increasingly reported in children, especially in those with abnormal dietary habits, mental or physical disabilities. We performed an extensive review of the literature analyzing studies published in the last 20 years focusing on clinical features, differential diagnosis and diagnostic delay. Fifteen articles were selected, collectively reporting a total of 166 children. Because of the wide clinical spectrum (musculoskeletal complaints and/or mucocutaneous lesions or systemic symptoms), scurvy can mimic several conditions, including autoimmune diseases, infections, and neoplasia. In addition, frequent findings such as normal nutritional status, anemia or elevated inflammatory markers may guide clinicians towards the abovementioned misdiagnoses. Scurvy should be considered in patients presenting with musculoskeletal complaints, not only in those with risk factors but also in healthy children. A focused dietary history and a careful physical examination, assessing other signs of vitamin C deficiency, are mandatory in these patients. When suspected, the dosage of serum vitamin C is the diagnostic gold standard; furthermore, imaging studies, performed by an expert radiologist, can reveal the typical features of scurvy. Only early diagnosis can avoid unnecessary investigations and potentially fatal complications of the disease.

High-dose vitamin C therapy for symptomatic deficiency in a patient with myasthenia gravis and Crohn's disease.

Vitamin C (ascorbic acid) is an essential water-soluble antioxidant, and deficiency (ie, plasma level <11 µmol/L) can result in scurvy. People at the highest risk for vitamin C deficiency (ie, scurvy) are those with inadequate intake, such as patients with alcohol abuse disorder, malnutrition, psychiatric disorders, restrictive eating habits, and food insecurity, as well as those with malabsorptive syndromes. We present a case of a 26-year-old woman with Crohn's colitis, myasthenia gravis, and juvenile rheumatoid arthritis who presented with frequent bruising, epistaxis, and excessive bleeding from small cuts and who was found to be deficient in vitamin C. Plasma levels initially normalized with oral vitamin C supplementation, but bleeding symptoms eventually returned despite high-dose oral supplementation with 2000 mg daily. She ultimately required routine intravenous supplementation in the home setting for the normalization of levels and the resolution of symptoms. Case reports of vitamin C deficiency typically involve patients with an inadequate intake of vitamin C-containing foods or inadequate absorption. In contrast, our patient reported a regular intake of vitamin C-containing foods, in addition to oral supplementation, but continued to have difficulty maintaining normal vitamin C levels. Scurvy should be considered for any patient with symptoms of bleeding, petechiae, or ecchymosis and, although it can typically be treated with oral vitamin C, intravenous repletion may be necessary in some cases.

Plasma Vitamin C Concentrations Were Negatively Associated with Tingling, Prickling or Pins and Needles Sensation in Patients with Postherpetic Neuralgia.

Vitamin C deficiency increases the risk of postherpetic neuralgia (PHN). In this cross-sectional study, the relationships among plasma vitamin C concentrations, pain and Leeds assessment of neuropathic symptoms and signs (LANSS) items were investigated during their first pain clinic visit of 120 PHN patients. The factors associated with vitamin C deficiency were determined. Independent predictors of vitamin C deficiency were presented as adjusted odds ratios (AOR) and 95% confidence intervals (CI). The patients had a high prevalence (52.5%) of vitamin C deficiency. Their plasma vitamin C concentrations were negatively associated with spontaneous pain and tingling, prickling or pins and needles sensation according to the LANSS questionnaire. Based on the receiver operator characteristic curve, the cutoffs for plasma vitamin C to predict moderate-to-severe and severe symptoms of sharp sensation were <7.05 and <5.68 mg/L, respectively. By comparison, the patients well-nourished with vitamin C had lower incidences of sharp sensations, sharp pain, and reddish skin. Multivariate analyses revealed that vitamin C deficiency was associated with the low intake of fruit/vegetables (AOR 2.66, 95% CI 1.09-6.48, p = 0.032), peptic ulcer disease (AOR 3.25, 95% CI 1.28-8.28, p = 0.014), and smoking (AOR 3.60, 95% CI 1.33-9.77, p = 0.010). Future studies are needed to substantiate these findings.

Patients Undergoing Myeloablative Chemotherapy and Hematopoietic Stem Cell Transplantation Exhibit Depleted Vitamin C Status in Association with Febrile Neutropenia.

Patients undergoing myeloablative chemotherapy and hematopoietic stem cell transplantation (HSCT) experience profound neutropenia and vulnerability to infection. Previous research has indicated that patients with infections have depleted vitamin C status. In this study, we recruited 38 patients with hematopoietic cancer who were undergoing conditioning chemotherapy and HSCT. Blood samples were collected prior to transplantation, at one week, two weeks and four weeks following transplantation. Vitamin C status and biomarkers of inflammation (C-reactive protein) and oxidative stress (protein carbonyls and thiobarbituric acid reactive substances) were assessed in association with febrile neutropenia. The vitamin C status of the study participants decreased from 44 ± 7 µmol/L to 29 ± 5 µmol/L by week one (p = 0.001) and 19 ± 6 µmol/L by week two (p < 0.001), by which time all of the participants had undergone a febrile episode. By week four, vitamin C status had increased to 37 ± 10 µmol/L (p = 0.1). Pre-transplantation, the cohort comprised 19% with hypovitaminosis C (i.e., <23 µmol/L) and 8% with deficiency (i.e., <11 µmol/L). At week one, those with hypovitaminosis C had increased to 38%, and at week two, 72% had hypovitaminosis C, and 34% had outright deficiency. C-reactive protein concentrations increased from 3.5 ± 1.8 mg/L to 20 ± 11 mg/L at week one (p = 0.002), and 119 ± 25 mg/L at week two (p < 0.001), corresponding to the development of febrile neutropenia in the patients. By week four, these values had dropped to 17 ± 8 mg/L (p < 0.001). There was a significant inverse correlation between C-reactive protein concentrations and vitamin C status (r = -0.424, p < 0.001). Lipid oxidation (thiobarbituric acid reactive substances (TBARS)) increased significantly from 2.0 ± 0.3 µmol/L at baseline to 3.3 ± 0.6 µmol/L by week one (p < 0.001), and remained elevated at week two (p = 0.003), returning to baseline concentrations by week four (p = 0.3). Overall, the lowest mean vitamin C values (recorded at week two) corresponded with the highest mean C-reactive protein values and lowest mean neutrophil counts. Thus, depleted vitamin C status in the HSCT patients coincides with febrile neutropenia and elevated inflammation and oxidative stress.

TET family dioxygenases and the TET activator vitamin C in immune responses and cancer.

Vitamin C serves as a cofactor for Fe(II) and 2-oxoglutarate-dependent dioxygenases including TET family enzymes, which catalyze the oxidation of 5-methylcytosine into 5-hydroxymethylcytosine and further oxidize methylcytosines. Loss-of-function mutations in epigenetic regulators such as TET genes are prevalent in hematopoietic malignancies. Vitamin C deficiency is frequently observed in cancer patients. In this review, we discuss the role of vitamin C and TET proteins in cancer, with a focus on hematopoietic malignancies, T regulatory cells, and other immune system cells.

Vitamin C deficiency mimicking inflammatory bone disease of the hand.

BACKGROUND: Severe vitamin C deficiency, or scurvy, encompasses a syndrome of multisystem abnormalities due to defective collagen synthesis and antioxidative functions. Among the more common presentations is a combination of oral or subcutaneous hemorrhage with lower extremity pain, the latter often exhibiting inflammatory bone changes on magnetic resonance imaging (MRI). CASE PRESENTATION: A 12-year-old male with anorexia nervosa presented with asymmetric painful swelling of multiple fingers of both hands. Imaging demonstrated soft tissue and bone marrow edema of several phalanges, without arthritis, concerning for an inflammatory process. Extensive imaging and laboratory evaluations were largely unrevealing, with the exception of a severely low vitamin C level and a moderately low vitamin D level. A diagnosis of scurvy was made and supplementation was initiated. Within 3 weeks of treatment, serum levels of both vitamins normalized and the digital abnormalities resolved on physical exam. CONCLUSIONS: This represents the first description of scurvy manifesting with bone and soft tissue changes limited to the hands. There must be a high index of suspicion for scurvy in children with restricted dietary intake or malabsorption who have bone pain, irrespective of location of the lesions.

The Pharmacokinetics of Vitamin C.

The pharmacokinetics of vitamin C (vitC) is indeed complex. Regulated primarily by a family of saturable sodium dependent vitC transporters (SVCTs), the absorption and elimination are highly dose-dependent. Moreover, the tissue specific expression levels and subtypes of these SVCTs result in a compartmentalized distribution pattern with a diverse range of organ concentrations of vitC at homeostasis ranging from about 0.2 mM in the muscle and heart, and up to 10 mM in the brain and adrenal gland. The homeostasis of vitC is influenced by several factors, including genetic polymorphisms and environmental and lifestyle factors such as smoking and diet, as well as diseases. Going from physiological to pharmacological doses, vitC pharmacokinetics change from zero to first order, rendering the precise calculation of dosing regimens in, for example, cancer and sepsis treatment possible. Unfortunately, the complex pharmacokinetics of vitC has often been overlooked in the design of intervention studies, giving rise to misinterpretations and erroneous conclusions. The present review outlines the diverse aspects of vitC pharmacokinetics and examines how they affect vitC homeostasis under a variety of conditions.

[Nutritional intervention in the control of gallstones and renal lithiasis]. / Intervención nutricional en el control de la colelitiasis y la litiasis renal.

INTRODUCTION: Cholelithiasis and kidney stones are frequent pathologies in developed countries. Gallstones can be pigmentary, cholesterol (75%) or mixed. Age, female sex, obesity, rapid weight loss, consumption of refined sugars, saturated fat, iron deficiency, vitamin D and low intake of fiber and vitamin C are factors associated with an increased risk of cholelithiasis. On the other hand, the intake of ω-3 fatty acids, oleic acid, calcium, magnesium, fiber, fruits and vegetables, dairy products, nuts, coffee, moderate consumption of alcohol, vitamin C supplements, physical exercise and a regular diet have a protective paper. The most frequent kidney stones are calcium oxalate followed by mixed ones (oxalate and calcium phosphate), struvite, uric acid and cystine. A high water intake is recommended (> 2.5 l / day), varying the type of recommended or unadvisable food depending on the type of calculus. In oxalic lithiasis it is recommended to reduce the consumption of meat, moderate that of spinach, Swiss chard, asparagus, chocolate and avoid excessive sodium intake. The administration of oxalate-degrading probiotics (Lactobacillus) may reduce intestinal absorption, although further studies are necessary to corroborate these results. In calcium phosphate acidifying diet is recommended and limit the consumption of coffee and tea. The prevention of uric calculus is based on hydration with alkalizing drinks and vegetarian diet, decreasing foods rich in purines (liver, kidney, fish eggs, anchovies, sardines and seafood) and in calculus of cystine diet is recommended alkalizing. Since the formation of struvite calculi is due to urinary infections, pharmacological treatment and the consumption of acidifying diets, moderation of the intake of phosphate-rich foods and limiting the contribution of fats and citrus fruits are necessary. The nutritional intervention is an effective measure in the prevention of biliary and renal lithiasis and prevent its recurrence.

INTRODUCCIÓN: La colelitiasis y litiasis renal son patologías frecuentes en países desarrollados. Los cálculos biliares pueden ser pigmentarios, de colesterol (75%) o mixtos. La edad, el sexo femenino, la obesidad, la pérdida rápida de peso, el consumo de azúcares refinados, la grasa saturada, la deficiencia de hierro y de vitamina D y la baja ingesta de fibra y vitamina C son factores asociados a mayor riesgo de colelitiasis. Por otro lado, la ingesta de ácidos grasos ω-3, ácido oleico, calcio, magnesio, fibra, frutas y verduras, lácteos, frutos secos, café, un consumo moderado de alcohol, suplementos de vitamina C, ejercicio físico y una alimentación regular desempeñan un papel protector. Las litiasis renales más frecuentes son de oxalato cálcico, seguidas de las mixtas (oxalato y fosfato cálcico), estruvita, ácido úrico y cistina. Se aconseja una elevada ingesta hídrica (> 2,5 l/día), variando el tipo de alimentos recomendados o desaconsejados en función del tipo de cálculo. En litiasis oxálica se recomienda reducir el consumo de carne, moderar el de espinacas, acelgas, espárragos, chocolate y evitar el aporte excesivo de sodio. La administración de probióticos degradantes de oxalato (Lactobacillus) podría reducir su absorción intestinal, aunque son necesarios más estudios para corroborar estos resultados. En las de fosfato cálcico se aconseja dieta acidificante y limitar el consumo de café y té. La prevención de cálculos de úrico está basada en la hidratación con bebidas alcalinizantes y dieta vegetariana, disminuyendo los alimentos ricos en purinas (hígado, riñón, huevas de pescado, anchoas, sardinas y mariscos), y en cálculos de cistina se aconseja el consumo de dietas alcalinizantes. Dado que la formación de cálculos de estruvita se debe a infecciones urinarias, es necesario un tratamiento farmacológico y el consumo de dietas acidificantes, moderar la ingesta de alimentos ricos en fosfatos y limitar el aporte de grasas y cítricos. La intervención nutricional es una medida eficaz en la prevención de la litiasis biliar y renal y para evitar su recurrencia.

Four-extremity amputation following disseminated intravascular coagulation and purpura fulminans.

Purpura fulminans (PF) is a rare but serious complication of septic shock in adults. The complex disease course makes it challenging to manage the condition. Here, we present the case of a healthy young woman who presented with sepsis and new-onset erythematous lesions 4 days after the vaginal delivery of a healthy baby. The infectious source could not be identified, and the patient was started on antibiotics and resuscitated. However, her condition worsened, and she developed disseminated intravascular coagulation and PF. The septic episode slowly decreased in severity, but she sustained extensive ischaemic injuries to her extremities, for which she underwent four-limb amputation.