Vitamin D deficiency causes rickets in an urban informal settlement in Kenya and is associated with malnutrition

Gene detection of VDR BsmI locus and its approteins, genes and growthplication in rational drug use in patients with osteoporosis

Aim: This paper determines the polymorphism distribution of the VDR BsmI gene in 350 patients and provides medication recommendations for osteoporosis based on detection results. Materials & methods: Chi-square tests compared genotype and allele frequencies with other populations. Results: Genotype frequencies were 91.66 bb, 8.72 Bb and 0.21% BB, with allelic frequencies of 95.43 b and 4.57% B, adhering to Hardy-Weinberg equilibrium. These findings suggest that VDR gene polymorphisms, particularly at the BsmIlocus, play an essential role in bone health and osteoporosis treatment. Genotype-based drug selection reduced adverse reactions from 14 to two cases. Conclusion: These findings improve clinical treatment efficacy and guide rational drug use for osteoporosis patients.

Serum 25-hydroxyvitamin D threshold and risk of rickets in young children: a systematic review and individual participant data meta-analysis to inform the development of dietary requirements for vitamin D

PURPOSE

The objective of this systematic review was to determine a minimum serum 25-hydroxyvitamin D (25OHD) threshold based on the risk of having rickets in young children. This work was commissioned by the WHO and FAO within the framework of the update of the vitamin D requirements for children 0-3 years old.

METHODS

A systematic search of Embase was conducted to identify studies involving children below  4 years of age with serum 25OHD levels and radiologically confirmed rickets, without any restriction related to the geographical location or language. Study-level and individual participant data (IPD)-level random effects multi-level meta-analyses were conducted. The odds, sensitivity and specificity for rickets at different serum 25OHD thresholds were calculated for all children as well as for children with adequate calcium intakes only.

RESULTS

A total of 120 studies with 5412 participants were included. At the study-level, children with rickets had a mean serum 25OHD of 23 nmol/L (95% CI 19-27). At the IPD level, children with rickets had a median and mean serum 25OHD of 23 and 29 nmol/L, respectively. More than half (55%) of the children with rickets had serum 25OHD below 25 nmol/L, 62% below 30 nmol/L, and 79% below 40 nmol/L. Analysis of odds, sensitivities and specificities for nutritional rickets at different serum 25OHD thresholds suggested a minimal risk threshold of around 28 nmol/L for children with adequate calcium intakes and 40 nmol/L for children with low calcium intakes.

CONCLUSION

This systematic review and IPD meta-analysis suggests that from a public health perspective and to inform the development of dietary requirements for vitamin D, a minimum serum 25OHD threshold of around 28 nmol/L and above would represent a low risk of nutritional rickets for the majority of children with an adequate calcium intake.

First Clinical Nutrition Outpatient Consultation: A Review of Basic Principles in Nutritional Care of Adults with Hematologic Disease

Methods

A bibliographic survey was carried out between 2020 and 2022 using two databases: PubMed/MEDLINE and Scientific Electronic Library Online (SciELO) and the information source Academic Google, irrespective of language or geography.

Results

In the first nutrition consultation (FNC), there should be an investigative direction focused on nutritional interventions in the short, medium, and long term. The record in the patient's medical record is relevant for carrying out the consultation, according to the recommendations of the normative councils of medicine and nutrition. The main steps to be followed are the investigation of the presence of food allergies and intolerances; the drugs/nutritional supplements in use; changes in the digestive tract; the presence or absence of picamalacia; and socioeconomic and lifestyle data. In addition, it is necessary to carry out laboratory evaluations, semiological assessment, anthropometric assessment, and assessment of food consumption. In the end, the nutritional approach should be composed of calculation of energy and macronutrient and micronutrient needs, intervention in nutritional status deviations, nutritional guidelines, and nutritional therapeutic planning of return, focusing on adherence to treatment.

Conclusion

The first nutrition consultation may represent investigative steps that help the clinical nutritionist in the management, allowing a longitudinal and specific nutritional therapeutic planning for patients assisted in large reference centers for hematological disease.

Children with severe acute malnutrition have high rates of bone resorption: A cross-sectional comparative study

Malnutrition in under-5 children (i.e., children younger than age 5 years) remains a major public health problem. Because of the reductive adaptation in children with severe acute malnutrition (SAM), changes in bone health are often subtle. We hypothesized that children with SAM have higher rates of bone resorption than bone formation, which can be assessed using bone turnover markers. In this cross-sectional comparative study, we evaluated the status of bone turnover markers, serum osteocalcin and serum tartrate-resistant acid phosphatase-5b (TRAP-5b) in under-5 children with SAM. Thirty children (6-59 months) with SAM (defined as per World Health Organization criteria) were enrolled as cases and another 30 children (age and sex matched) with normal nutritional status (weight for height -1 standard deviation [SD] to +1 SD) were enrolled for comparison of bone turnover markers. Serum TRAP-5b concentrations were significantly higher in children with SAM compared with children with normal nutritional status (mean [SD] 22.6 [15.3] vs. 11.3 [9.6], P = .009), whereas serum osteocalcin concentrations were comparable between the 2 groups (mean [SD] 40.6 [17.9] vs. 36.0 [12.5], P = .344). Frequency of hypocalcemia and vitamin D deficiency were also significantly high in children with SAM (P < .05). An inverse correlation was found between serum calcium and serum osteocalcin (r = -0.383, P < .05). Our results indicate that children with SAM have a higher bone resorption rate than children with normal nutrition status indicating compromised bone health.

The effect of antiretroviral therapy initiation on vitamin D levels and four oral diseases among Kenyan children and adolescents living with HIV

OBJECTIVES

The impact of antiretroviral treatment (ART) on the occurrence of oral diseases among children and adolescents living with HIV (CALHIV) is poorly understood. The aim of this study was to determine the effect of ART timing on vitamin D levels and the prevalence of four oral diseases (dry mouth, dental caries, enamel hypoplasia, and non-herpes oral ulcer) among Kenyan CALHIV from two pediatric HIV cohorts.

METHODS

This nested cross-sectional study was conducted at the Kenyatta National Hospital, Nairobi, Kenya. CALHIV, 51 with early-ART initiated at <12 months of age and 27 with late-ART initiated between 18 months-12 years of age, were included. Demographics, HIV diagnosis, baseline CD4 and HIV RNA viral load data were extracted from the primary study databases. Community Oral Health Officers performed oral health examinations following standardized training.

RESULTS

Among 78 CALHIV in the study, median age at the time of the oral examination was 11.4 years old and median ART duration at the time of oral examination was 11 years (IQR: 10.1, 13.4). Mean serum vitamin D level was significantly higher among the early-ART group than the late-ART group (29.5 versus 22.4 ng/mL, p = 0.0002). Children who received early-ART had a 70% reduction in risk of inadequate vitamin D level (<20 ng/mL), compared to those who received late-ART (p = 0.02). Although both groups had similar prevalence of oral diseases overall (early-ART 82.4%; late-ART 85.2%; p = 0.2), there was a trend for higher prevalence of dry mouth (p = 0.1) and dental caries (p = 0.1) in the early versus late ART groups. The prevalence of the four oral diseases was not associated with vitamin D levels (p = 0.583).

CONCLUSIONS

After >10 years of ART, CALHIV with early-ART initiation had higher serum vitamin D levels compared to the late-ART group. The four oral diseases were not significantly associated with timing of ART initiation or serum vitamin D concentrations in this cohort. There was a trend for higher prevalence of dry mouth and dental caries in the early-ART group, probably as side-effects of ART.

Analysis of Vitamin D Components in Serum of Minors by UHPLC-MS/MS

Serum 25-hydroxyvitamin D [25(OH)D] concentration represents the body's reserves of vitamin D, which is mostly used by clinicians to evaluate the storage status of vitamin D in the body. The present study aimed to investigate the serum vitamin D components in different health status of minors to correctly evaluate the vitamin D storage in vivo. A total of 2,270 minors were included in the study, which was divided into healthy group (1,204 cases) and disease group (1,066 cases, including 270 short stature, 433 respiratory infections, 175 malnutrition and 188 tic disorder subjects). The levels of 25-hydroxyvitamin D₂ [25(OH)D₂] and 25-hydroxyvitamin D₃ [25(OH)D₃] were measured by UHPLC-MS/MS in all subjects, and the 25(OH)D₃ activity equivalents [25(OH)D₃-AE] and 25(OH)D were calculated. In addition, the 3-epi-25-hydroxyvitamin D₃ [3-epi-25(OH)D₃] concentrations of 278 subjects (including 147 healthy and 131 disease subjects) were measured by random sampling. 25(OH)D₂, 25(OH)D₃, 25(OH)D and 25(OH)D₃-AE levels in disease group were significantly lower than those in healthy group (p<0.001). According to the level of 25(OH)D, the sufficiency of vitamin D [25(OH)D≥30 ng/mL] was 65.4% in healthy group and 50.5% in disease group. When the 25(OH)D₂ activity was converted into 25(OH)D₃-AE, 53.2% of the patients in the healthy group had sufficiency vitamin D, and 39.1% in the disease group. The 3-epi-25(OH)D₃ level in the disease group was significantly lower than that in the healthy group (p<0.001). Not only the 25(OH)D, but also the both of 25(OH)D₂ and 25(OH)D₃ levels may overestimate the vitamin D status in subjects. For accurate evaluation, at least the serum levels of 25(OH)D₂, 25(OH)D₃ and 3-epi-25(OH)D₃ should be determined simultaneously.

Rickets in Children: An Update

Rickets refers to a deficient mineralization of the growth plate cartilage, predominantly affecting longer bones. Despite the fact that preventive measures are available, it is still a common disease worldwide; nutritional rickets, due to vitamin D deficiency or dietary calcium inadequate intake, remains the most common form. Medical history, physical examination, radiologic features and biochemical tests are essential for diagnosis. Although recent studies suggest hypophosphatemia as the leading alteration, rickets is classically divided into two categories: calcipenic rickets and phosphopenic rickets. Knowledge of this categorization and of respective clinical and laboratory features is essential for rapid diagnosis and correct management. The aim of this review is to analyze the epidemiological, pathogenetic, clinical, and therapeutic aspects of the different forms of rickets, describing the novelties on this “long-lived” disease.

Prevalence and predictors of vitamin D deficiency in young African children

BACKGROUND

Children living in sub-Saharan Africa have a high burden of rickets and infectious diseases, conditions that are linked to vitamin D deficiency. However, data on the vitamin D status of young African children and its environmental and genetic predictors are limited. We aimed to examine the prevalence and predictors of vitamin D deficiency in young African children.

METHODS

We measured 25-hydroxyvitamin D (25(OH)D) and typed the single nucleotide polymorphisms, rs4588 and rs7041, in the GC gene encoding the vitamin D binding protein (DBP) in 4509 children aged 0-8 years living in Kenya, Uganda, Burkina Faso, The Gambia and South Africa. We evaluated associations between vitamin D status and country, age, sex, season, anthropometric indices, inflammation, malaria and DBP haplotypes in regression analyses.

RESULTS

Median age was 23.9 months (interquartile range [IQR] 12.3, 35.9). Prevalence of vitamin D deficiency using 25(OH)D cut-offs of < 30 nmol/L and < 50 nmol/L was 0.6% (95% CI 0.4, 0.9) and 7.8% (95% CI 7.0, 8.5), respectively. Overall median 25(OH)D level was 77.6 nmol/L (IQR 63.6, 94.2). 25(OH)D levels were lower in South Africa, in older children, during winter or the long rains, and in those with afebrile malaria, and higher in children with inflammation. 25(OH)D levels did not vary by stunting, wasting or underweight in adjusted regression models. The distribution of Gc variants was Gc1f 83.3%, Gc1s 8.5% and Gc2 8.2% overall and varied by country. Individuals carrying the Gc2 variant had lower median 25(OH)D levels (72.4 nmol/L (IQR 59.4, 86.5) than those carrying the Gc1f (77.3 nmol/L (IQR 63.5, 92.8)) or Gc1s (78.9 nmol/L (IQR 63.8, 95.5)) variants.

CONCLUSIONS

Approximately 0.6% and 7.8% of young African children were vitamin D deficient as defined by 25(OH)D levels < 30 nmol/L and < 50 nmol/L, respectively. Latitude, age, season, and prevalence of inflammation and malaria should be considered in strategies to assess and manage vitamin D deficiency in young children living in Africa.

The association of serum levels of zinc and vitamin D with wasting among Iranian pre-school children

PURPOSE

Wasting is a main indicator of Child's undernutrition that is associated with several non-communicable diseases and child mortality. This is the first population-based study which evaluated the association of serum zinc and vitamin D levels with wasting in a Middle East region. We also reported the prevalence of vitamin D and zinc deficiencies among Iranian pre-school children aged 6 years.

METHODS

This was a multicenter cross-sectional study that included 425 children aged between 5 and 7 years (on average 6 years) with BMI-for-age Z-scores of < - 1 SD resident in urban and rural areas of Iran in the spring of 2012 as part of the National Integrated Micronutrient Survey 2 (NIMS-2). Anthropometric measurements and blood sampling were obtained. The prevalence of vitamin D and zinc deficiencies together with the correlations of these variables with the increase of BMI-for-age Z-scores were evaluated.

RESULTS

The prevalence of vitamin D and zinc deficiencies was 18.8% and 12.7%, respectively. In addition, 31.1% of children were wasted. Children in the second tertile of 25(OH)D levels were less likely to have wasting compared with those in the first tertile in both crude and adjusted models (OR 0.47, 95% CI 0.27-0.83). A significant inverse association was found between serum levels of zinc and wasting (OR 0.57, 95% CI 0.34-0.96); such that after adjusting for confounders, children in the highest tertile of serum zinc had 47% less odds of wasting compared with those in the first tertile (OR 0.53, 95% CI 0.31-0.91).

CONCLUSION

The prevalence of vitamin D and zinc deficiencies among Iranian pre-school children aged 6 years was 18.8 and 12.7%, respectively. Serum levels of vitamin D and zinc were inversely associated with wasting either before or after controlling for confounders.

LEVEL OF EVIDENCE

Level III, case-control analytic studies.

Prevalence and predictors of hypocalcaemia in severe acute malnutrition

OBJECTIVE

To determine the prevalence and predictors of hypocalcaemia in under-five children (1-59 months) hospitalised with severe acute malnutrition (SAM).

DESIGN

A cross-sectional study was designed to determine the prevalence of hypocalcaemia among children hospitalised with SAM. Serum Ca and 25-hydroxycholecalciferol (25-(OH)D) were estimated. Hypocalcaemia was defined as serum Ca (albumin-adjusted) <2·12 mmol/l. To identify the clinical predictors of hypocalcaemia, a logistic regression model was constructed taking hypocalcaemia as a dependent variable, and sociodemographic and clinical variables as independent variables.

SETTING

A tertiary care hospital in Delhi, between November 2017 and April 2019.

PARTICIPANTS

One-hundred and fifty children (1-59 months) hospitalised with SAM were enrolled.

RESULTS

Hypocalcaemia was documented in thirty-nine (26 %) children hospitalised with SAM, the prevalence being comparable between children aged <6 months (11/41, 26·8 %) and those between 6 and 59 months (28/109, 25·7 %) (P = 0·887). Vitamin D deficiency (serum 25-(OH)D <30 nmol/l) and clinical rickets were observed in ninety-eight (65·3 %) and sixty-three (42 %) children, respectively. Hypocalcaemia occurred more frequently in severely malnourished children with clinical rickets (OR 6·6, 95 % CI 2·54, 17·15, P < 0·001), abdominal distension (OR 4·5, 95 % CI 1·39, 14·54, P = 0·012) and sepsis (OR 2·6, 95 % CI 1·00, 6·57, P = 0·050).

CONCLUSION

Rickets and hypocalcaemia are common in children with SAM. Routine supplementation of vitamin D should be considered for severely malnourished children. Ca may be empirically prescribed to severely malnourished children with clinical rickets, abdominal distension and/or sepsis.

High-dose vitamin D3 in the treatment of severe acute malnutrition: a multicenter double-blind randomized controlled trial

Background

Vitamin D deficiency is common in children with severe acute malnutrition, in whom it is associated with severe wasting. Ready-to-use therapeutic food (the standard treatment) contains modest amounts of vitamin D that do not reliably correct deficiency.

Objective

The aim of this study was to determine whether high-dose oral vitamin D3 enhances weight gain and development in children with uncomplicated severe acute malnutrition.

Design

We conducted a randomized placebo-controlled trial of high-dose vitamin D3 supplementation in children aged 6-58 mo with uncomplicated severe acute malnutrition in Pakistan. Participants were randomly assigned to receive 2 oral doses of 200,000 IU vitamin D3 or placebo at 2 and 4 wk after starting ready-to-use therapeutic food. The primary outcome was the proportion of participants gaining >15% of baseline weight at 8 wk after starting ready-to-use therapeutic food (the end of the study). Secondary outcomes were mean weight-for-height or -length z score and the proportion of participants with delayed development at the end of the study (assessed with the Denver Development Screening Tool II), adjusted for baseline values.

Results

Of the 194 randomly assigned children who started the study, 185 completed the follow-up and were included in the analysis (93 assigned to intervention, 92 to control). High-dose vitamin D3 did not influence the proportion of children gaining >15% of baseline weight at the end of the study (RR: 1.04; 95% CI: 0.94,1.15, P = 0.47), but it did increase the weight-for-height or -length z score (adjusted mean difference: 1.07; 95% CI: 0.49,1.65, P < 0.001) and reduce the proportion of participants with delayed global development [adjusted RR (aRR): 0.49; 95% CI: 0.31, 0.77, P = 0.002], delayed gross motor development (aRR: 0.29; 95% CI: 0.13, 0.64, P = 0.002), delayed fine motor development (aRR: 0.59; 95% CI: 0.38, 0.91, P = 0.018), and delayed language development (aRR: 0.57; 95% CI: 0.34, 0.96, P = 0.036).

Conclusions

High-dose vitamin D3 improved the mean weight-for-height or -length z score and developmental indexes in children receiving standard therapy for uncomplicated severe acute malnutrition in Pakistan. This trial was registered at clinicaltrials.gov as NCT03170479.

The impact of rickets on growth and morbidity during recovery among children with complicated severe acute malnutrition in Kenya: A cohort study

The effects of rickets on children recovery from severe acute malnutrition (SAM) are unknown. Rickets may affect both growth and susceptibility to infectious diseases. We investigated the associations of clinically diagnosed rickets with life‐threatening events and anthropometric recovery during 1 year following inpatient treatment for complicated SAM. This was a secondary analysis of clinical trial data among non‐human immunodeficiency virus‐infected Kenyan children with complicated SAM (2–59 months) followed for 1 year posthospital discharge (ClinicalTrials.gov ID NCT00934492). The outcomes were mortality, hospital readmissions, and growth during 12 months. The main exposure was clinically diagnosed rickets at baseline. Of 1,778 children recruited, 230 (12.9%, 95% CI [11.4, 14 .6]) had clinical signs of rickets at baseline. Enrolment at an urban site, height‐for‐age and head circumference‐for‐age z scores were associated with rickets. Rickets at study enrolment was associated with increased mortality (adjusted Hazard Ratio [aHR] 1.61, 95% CI [1.14, 2.27]), any readmission (aHR 1.37, 95% CI [1.09, 1.72]), readmission for severe pneumonia (aHR 1.37, 95% CI [1.05, 1.79]), but not readmission with diarrhoea (aHR 1.05, 95% CI [0.73, 1.51]). Rickets was associated with increased height gain (centimetres), adjusted regression coefficient 0.19 (95% CI [0.10, 0.28]), but not changes in head circumference, mid‐upper arm circumference, or weight. Rickets was common among children with SAM at urban sites and associated with increased risks of severe pneumonia and death. Increased height gain may have resulted from vitamin D and calcium treatment. Future work should explore possibility of other concurrent micronutrient deficiencies and optimal treatment of rickets in this high‐risk population.

Using data from a multi-hospital clinical network to explore prevalence of pediatric rickets in Kenya

Background: Nutritional rickets is a public health concern in developing countries despite tropical climates and a re-emerging issue in developed countries. In this study, we reviewed pediatric admission data from the Clinical Information Network (CIN) to help determine hospital and region based prevalence of rickets in three regions of Kenya (Central Kenya, Western Kenya and Nairobi County). We also examine the association of rickets with other diagnosis, such as malnutrition and pneumonia, and study the effect of rickets on regional hospital stays.

Methods: We analyzed discharge records for children aged 1 month to 5 years from county (formerly district) hospitals in the CIN, with admissions from February 1 ^st 2014 to February 28 ^th 2015. The strength of the association between rickets and key demographic factors, as well as with malnutrition and pneumonia, was assessed using odds ratios. The Fisher exact test was used to test the significance of the estimated odd ratios. Kaplan-Meier curves were used to analyze length of hospital stays.

Results: There was a marked difference in prevalence across the three regions, with Nairobi having the highest number of cases of rickets at a proportion of 4.01%, followed by Central Region at 0.92%. Out of 9756 admissions in the Western Region, there was only one diagnosis of rickets. Malnutrition was associated with rickets; this association varied regionally. Pneumonia was found to be associated with rickets in Central Kenya. Children diagnosed with rickets had longer hospital stays, even when cases of malnutrition and pneumonia were excluded in the analysis.

Conclusion: There was marked regional variation in hospital based prevalence of rickets, but in some regions it is a common clinical diagnosis suggesting the need for targeted public health interventions. Factors such as maternal and child nutrition, urbanization and cultural practices might explain these differences.

Vitamin D deficiency causes rickets in an urban informal settlement in Kenya and is associated with malnutrition

The commonest cause of rickets worldwide is vitamin D deficiency, but studies from sub-Saharan Africa describe an endemic vitamin D-independent form that responds to dietary calcium enrichment. The extent to which calcium-deficiency rickets is the dominant form across sub-Saharan Africa and in other low-latitude areas is unknown. We aimed to characterise the clinical and biochemical features of young children with rickets in a densely populated urban informal settlement in Kenya. Because malnutrition may mask the clinical features of rickets, we also looked for biochemical indices of risk in children with varying degrees of acute malnutrition. Twenty one children with rickets, aged 3 to 24 months, were identified on the basis of clinical and radiologic features, along with 22 community controls, and 41 children with either severe or moderate acute malnutrition. Most children with rickets had wrist widening (100%) and rachitic rosary (90%), as opposed to lower limb features (19%). Developmental delay (52%), acute malnutrition (71%), and stunting (62%) were common. Compared to controls, there were no differences in calcium intake, but most (71%) had serum 25-hydroxyvitamin D levels below 30 nmol/L. These results suggest that rickets in young children in urban Kenya is usually driven by vitamin D deficiency, and vitamin D supplementation is likely to be required for full recovery. Wasting was associated with lower calcium (p = .001), phosphate (p < .001), 25-hydroxyvitamin D (p = .049), and 1,25-dihydroxyvitamin D (p = 0.022) levels, the clinical significance of which remain unclear.