¿Existe déficit de vitamina D en los niños de una ciudad soleada del Mediterráneo?

Mild Hypophosphatemia-Associated Conditions in Children: The Need for a Comprehensive Approach

To better understand the causes of hypophosphatemia in children, we evaluated all serum phosphate tests performed in a tertiary hospital with unexpected but persistent temporary or isolated hypophosphatemia over an 18 year period. We collected 29,279 phosphate tests from 21,398 patients, of which 268 (1.2%) had at least one result showing hypophosphatemia. We found that endocrinopathies (n = 60), tumors (n = 10), and vitamin D deficiency (n = 3) were the medical conditions most commonly associated with mild hypophosphatemia, but in many patients the cause was unclear. Among patients with endocrinopathies, those with diabetes mellitus were found to have lower mean serum phosphate levels (mean 3.4 mg/dL) than those with short stature (3.7 mg/dL) or thyroid disorders (3.7 mg/dL). In addition, we found a correlation between glycemia and phosphatemia in patients with diabetes. However, despite the potential relevance of monitoring phosphate homeostasis and the underlying etiologic mechanisms, renal phosphate losses were estimated in less than 5% of patients with hypophosphatemia. In the pediatric age group, malignancies, hypovitaminosis D, and endocrine disorders, mostly diabetes, were the most common causes of hypophosphatemia. This real-world study also shows that hypophosphatemia is frequently neglected and inadequately evaluated by pediatricians, which emphasizes the need for more education and awareness about this condition to prevent its potentially deleterious consequences.

[Vitamin D insufficiency in a healthy pediatric population. The importance of early prophylaxis]

Introduction

Introduction: vitamin D maintains the concentration of calcium and phosphorus within the physiological range, allowing normal metabolism and bone mineralization. Recently, vitamin D deficiency has been related not only with rickets but also with an increased risk of other pathologies. The aim of this descriptive, observational, cross-sectional study was to assess vitamin D concentration levels in a healthy pediatric population, as well as the current situation of prophylaxis. Vitamin D determination was measured by serum 25-hydroxyvitamin D (25(OH)D) concentration. Methods: a total of 258 healthy patients between 3 months and 15 years of age were enrolled (6.77 ± 3.95 years; 73.6 % were male). Results: the mean value of 25-hydroxyvitamin D was 26.60 ng/mL ± 8.02 ng/mL, and up to 20.9 % of the population showed insufficient levels. Statistically significant differences in vitamin D levels were observed between ages (p = 0.002), ethnicity groups (p = 0.038), and skin types (p = 0.000). In addition, a higher prevalence of vitamin D insufficiency in children who had never previously received vitamin D supplementation (41.6 %) was observed compared to those that had taken supplementation in the first year of life (16.7 %). Conclusion: our study shows a high prevalence of vitamin D deficiency among healthy children, and the benefit of prophylaxis with vitamin D supplementation.

Validity and Reliability of a Nutritional Screening Tool (SCAN) in Children Newly Diagnosed with Cancer

No standardized approach towards nutritional screening and assessment of pediatric oncology patients has been established. The nutrition screening tool for childhood cancer (SCAN) has been previously published as an effective screening method. This is an observational cross-sectional study to assess the validity and reliability of the SCAN tool, compare it to the detection of undernutrition using standard measures of assessment, and determine the overall prevalence of malnutrition and micronutrients alterations in our cohort. We included children newly diagnosed with cancer in a pediatric tertiary hospital in Madrid, Spain from August 2018 to May 2019. The following measurements were performed: SCAN questionnaire, anthropometric measurements, nutritional markers in blood, and micronutrient levels. A total of 49 patients were included. 22 patients (45%) were at risk of malnutrition according to the SCAN questionnaire. Four patients (8%) could be diagnosed with moderate undernutrition. These undernourished patients were distributed homogeneously among at-risk and not at-risk populations identified by the SCAN tool. Several micronutrient deficiencies were identified. We conclude that the SCAN questionnaire is an easy-to-use tool for everyday clinical practice. By not including anthropometric measurements it misses patients considered to be malnourished. Future data might help clarify if it is an effective tool in predicting a higher nutritional risk during the entire treatment course.

Association of Vitamin D Receptor Gene Polymorphisms with Serum Vitamin D Levels in a Greek Rural Population (Velestino Study)

BACKGROUND/AIM

An alarming increase in vitamin D deficiency even in sunny regions highlights the need for a better understanding of the genetic background of the vitamin D endocrine system and the molecular mechanisms of gene polymorphisms of the vitamin D receptor (VDR). In this study, the serum levels of 25(OH)D3 were correlated with common VDR polymorphisms (ApaI, BsmI, FokI, and TaqI) in 98 subjects of a Greek homogeneous rural population.

METHODS

25(OH)D3 concentration was measured by ultra-HPLC, and the VDR gene polymorphisms were identified by quantitative real-time PCR followed by amplicon high-resolution melting analysis.

RESULTS

Subjects carrying either the B BsmI (OR: 0.52, 95% CI: 0.27-0.99) or t TaqI (OR: 2.06, 95%: 1.06-3.99) allele presented twice the risk for developing vitamin D deficiency compared to the reference allele. Moreover, subjects carrying 1, 2, or all 3 of these genotypes (BB/Bb, Tt/tt, and FF) demonstrated 2-fold (OR: 2.04, 95% CI: 0.42-9.92), 3.6-fold (OR: 3.62, 95% CI: 1.07-12.2), and 7-fold (OR: 6.92, 95% CI: 1.68-28.5) increased risk for low 25(OH)D3 levels, respectively.

CONCLUSIONS

Our findings reveal a cumulative effect of specific VDR gene polymorphisms that may regulate vitamin D concentrations explaining, in part, the paradox of vitamin D deficiency in sunny regions, with important implications for precision medicine.

The association between atopic dermatitis and serum 25-hydroxyvitamin D in children: Influence of sun exposure, diet, and atopy features-A cross-sectional study

BACKGROUND

Previous studies have linked low serum vitamin D (VD) or 25-hydroxyvitamin D (25(OH)D) levels with increased severity of atopic dermatitis (AD) in children.

OBJECTIVE

To investigate the association between serum VD (25(OH)D) levels and AD and AD severity, considering the influence of diet and sun exposure.

METHODS

We performed a prospective cross-sectional study of healthy controls and children diagnosed with AD. Participants were recruited between January 2011 and December 2012, and the following parameters were assessed: age, sex, body mass index (BMI), AD severity, Fitzpatrick skin type, asthma and rhinitis history, dietary VD intake, daily potential sun-induced VD production, sunscreen use, 25(OH)D and IgE serum levels, and results of the ImmunoCAP Phadiatop Infant test.

RESULTS

The study population consisted of 105 healthy controls and 134 AD patients. Serum 25(OH)D levels were significantly lower in moderate and severe AD than in mild AD, although this association was only significant for patients with light Fitzpatrick skin type (mean(SD) 36.7 (11.9) ng/mL; moderate 28.8 [11.5] ng/mL; and severe 27.6 [12.1] ng/mL, P = .045). Logistic regression analysis revealed a positive association between severe AD and both positive ImmunoCAP Phadiatop test and BMI.

CONCLUSION

Our data support an association between VD deficiency and AD severity only in patients with light complexion.

Roles of Vitamins D and K, Nutrition, and Lifestyle in Low-Energy Bone Fractures in Children and Young Adults

The research on skeletal system health in children and young adults, while recognizing the important role of calcium and vitamin D, goes beyond these nutritional standards. This review focuses on the role of vitamin K in combination with vitamin D and other factors in bone health. The current understanding is that maintaining bone health and prevention of low-energy fractures in any pediatric population includes nutritional factors combined with an active lifestyle. Calcium, vitamin D, and vitamin K supplementation contribute independently and collectively to bone health. The beneficial role of vitamin K, particularly vitamin K2 as menaquinone-7 (MK-7), in bone and cardiovascular health is reasonably well supported scientifically, with several preclinical, epidemiological, and clinical studies published over the last decade. Osteocalcin and matrix-Gla (glutamate-containing) protein (MGP) exemplify vitamin K-dependent proteins involved in building bone matrix and keeping calcium from accumulating in the arterial walls, respectively. An important part of the mechanism of vitamin K involves carboxylation and posttranslational activation of the family of vitamin K-dependent proteins, which prevent expression of pro-inflammatory factors and support improvement in bone mineral concentration, bone mineral density, and the quality of bone matrix. Understanding the combined approach to a healthy skeletal system in children and young adults, including the roles of vitamins D and K, calcium, healthy diet, and exercise, is particularly important in view of reports of subclinical insufficiency of vitamins D and K in otherwise healthy pediatric populations with low-energy bone fractures.