Osteoporosis in children and adolescents

Analyzing Patterns of Skeletal Indicators of Developmental Stress Through the Double Lens of Ontogeny and the Life Course Approach in a Contemporary Reference Sample

OBJECTIVES

Skeletal indicators of developmental stress are commonly used to assess health, disease, and patterns of morbidity and mortality in past populations. Incorporating information about individual life history, such as adverse life events, allows for a more thorough understanding of their etiology. This paper adopts the double lens of ontogeny and the life course to analyze indicators of developmental stress in relation to known individual pathologies and developmental patterns of the cranium, vertebrae, and long bones.

MATERIAL AND METHODS

Six skeletal indicators were collected on CT scans or virtual skeletal reconstructions of 1033 contemporary deceased male and female individuals aged between 0 and 20 years from New Mexico: cribra orbitalia, porotic hyperostosis, Harris lines, stunting, vertebral neural canal diameters, and bone mineral density. Autopsy reports provided information on age, sex, disease type, and duration. Polychoric and polyserial correlations, boxplots, balloon plots, factor analyses of mixed data, and cluster analyses were used to explore patterns among indicators, ontogeny, sex, and disease.

RESULTS

The presence and prevalence of indicators varied depending on age and disease: Harris lines, stunted growth, and cribra orbitalia were common in younger age groups and in cases of long-term or respiratory illnesses, while porotic hyperostosis was more prevalent in adolescent and young adult males.

DISCUSSION

Skeletal indicators of developmental stress are most likely associated with the timing of adverse life events in relation to the corresponding ontogenetic patterns, developmental sensitivity to stressors, and developmental plasticity/canalization of the different skeletal elements that bear them.

Safety and efficacy of monthly high-dose vitamin D3 supplementation in children and adolescents with sickle cell disease

Little is known about the impact of vitamin D supplementation on hand grip strength (HGS) and health-related quality of life (HRQoL) in children and adolescents with sickle cell disease (SCD). We aimed to evaluate the safety and efficacy of monthly high-dose vitamin D3 supplementation and its implications on bone mineral density (BMD), HGS, and HRQoL in patients with SCD and healthy controls. The study included 42 children with SCD and 42 healthy matched controls. The study participants were supplemented with high-dose monthly oral vitamin D3. Changes in the serum level of 25(OH) vitamin D3, maximum HGS, and BMD from baseline to 6 months were assessed, and the HRQoL questionnaire and Childhood Health Assessment Questionnaire (CHAQ) were used to evaluate the functional capacity. At baseline, SCD subjects had poorer growth status indicated by negative Z scores. Suboptimal BMD was detected by significantly lower Z score, and lower HGS and worse HRQL parameters were found compared to the controls (P < 0.001). Median 25(OH) vitamin D3 was significantly lower in SCD patients compared to controls (16.5 vs. 28 ng/mL, respectively (P < 0.001)). After 6 months of vitamin D supplementation, there was significant improvement in the DEXA Z-score (P < 0.001), limitation of physical health (P = 0.02), pain scores (P < 0.001), and CHAQ grades (P = 0.01) in SCD patients. A significant improvement in HGS (P < 0.001 and P = 0.005) as well as the CHAQ score (P < 0.001 and P = 0.003) was detected in the SCD group and controls, respectively. There were no reported clinical adverse events (AEs) or new concomitant medications (CMs) during the study duration, and safe levels of Ca and 25 (OH) D3 were observed at 3 and 6 months for both groups. There was a significant positive correlation between HGS and total physical score (r = 0.831, P < 0.001) and a negative correlation with CHAQ score (r =  - 0.685, P < 0.001). We also detected a significant positive correlation between vitamin D levels at 6 months and HGS (r = 0.584, P < 0.001), pain score (r = 0.446, P < 0.001), and a negative correlation with CHAQ score (r =  - 0.399, P < 0.001).   Conclusion: Monthly oral high-dose vitamin D supplementation was safe and effective in improving vitamin D levels, HGS, and HRQoL in SCD children and healthy subjects, and BMD scores in SCD patients. Further randomized controlled trials are warranted to assess an optimal dosing strategy and to investigate the impact on clinically significant outcomes in children and adolescents with SCD and their healthy counterparts.   Trial registration: ClinicalTrials.gov , identifier NCT06274203, date of registration: 23/02/2024, retrospectively registered. What is known: • Several studies have reported a high prevalence of vitamin D deficiency and suboptimal bone mineral density (BMD) in sickle cell disease (SCD) patients. • Musculoskeletal dysfunction is reported in SCD patients with a negative impact on physical activity and health-related quality of life (HRQL). • Little is known regarding the impact of vitamin D3 supplementation in children and adolescents with SCD. What is new: • We found that monthly oral high-dose vitamin D3 supplementation was safe, tolerated, and effective in improving serum vitamin D levels, HGS, BMD scores, and HRQL in SCD patients.

Association between weight-adjusted waist index and bone mineral density in adolescents

The negative effects of obesity and excess body fat on bone mineral density (BMD) have been widely reported. As opposed to waist circumference (WC) or body mass index (BMI), weight-adjusted waist index (WWI) is a superior method for assessing obesity. WWI also indicates centripetal obesity independently of the weight of the individual. An investigation of WWI and adolescents' BMD was conducted in this study. The National Health and Nutrition Examination Survey (NHANES) 2011-2018 provided the data for this cross-sectional investigation. In this study, weighted multivariate logit models were employed to assess the correlation between teenage BMD and WWI. Additionally, we conducted interaction tests and subgroup analysis. Through multivariate linear regression, we discovered that WWI was negatively linked with lumbar, trunk, and total BMD but not pelvis BMD in this study, which included 6828 subjects. We found that each unit increase in WWI resulted in a lumbar BMD decline of 0.04 g/cm2 (95%CI -0.04, -0.04), a trunk BMD decrease of 0.03 g/cm2 (95%CI -0.03, -0.02), and a total BMD decrease of 0.02 g/cm2 (95%CI -0.02, -0.02). In conclusion, in US teenagers, there were negative connections discovered between WWI and lumbar, trunk, and total BMD, but not pelvis BMD.

Dual x-ray absorptiometry monitoring in pediatric short bowel syndrome: an integrative review

OBJECTIVE

To analyze the bone health of pediatric patients with short bowel syndrome intestinal failure (SBS-IF).

DATA SOURCE

An integrative literature review was performed using the data published in the MEDLINE-PubMed and Scientific Electronic Library Online (SciELO) databases between January 2010 and April 2021, and through a manual search of the reference lists of relevant studies. Studies were included if they assessed bone mineral density by the Dual X-Ray Absorptiometry (DXA) technique, incorporated pediatric patients (up to 20 years of age) with SBS under parenteral nutrition (PN) and were written in English. Eleven primary sources met the inclusion criteria for this study.

DATA SYNTHESIS

Pediatric patients with SBS-IF under long-term parenteral nutrition experienced frequent changes in bone metabolism, leading to osteoporotic fractures and growth failure. These patients have deficiencies in multiple nutrients, such as calcium, magnesium, phosphorus, and vitamin D. Consequently, there are variations in the secretion and regulation of the parathyroid hormone. In addition, the pharmacotechnical limitations related to calcium and phosphorus in the PN solution, use of glucocorticoids, and difficulty performing physical activity are risk factors for the development of metabolic bone disease in pediatric patients with SBS-IF.

CONCLUSIONS

Low bone mineral density was associated with a high risk of developing osteoporosis, fractures, and growth deficiency in pediatric patients with SBS-IF on PN therapy in the long term.

Bone Fracture in Rett Syndrome: Mechanisms and Prevention Strategies

The present study aimed to evaluate the burden and management of fragility fractures in subjects with Rett syndrome. We searched all relevant medical literature from 1 January 1986 to 30 June 2023 for studies under the search term "Rett syndrome and fracture". The fracture frequency ranges from a minimum of 13.9% to a maximum of 36.1%. The majority of such fractures occur in lower limb bones and are associated with low bone mineral density. Anticonvulsant use, joint contractures, immobilization, low physical activity, poor nutrition, the genotype, and lower calcium and vitamin D intakes all significantly impair skeletal maturation and bone mass accrual in Rett syndrome patients, making them more susceptible to fragility fractures. This review summarizes the knowledge on risk factors for fragility fracture in patients with Rett syndrome and suggests a possible diagnostic and therapeutic care pathway for improving low bone mineral density and reducing the risk of fragility fractures. The optimization of physical activity, along with adequate nutrition and the intake of calcium and vitamin D supplements, should be recommended. In addition, subjects with Rett syndrome and a history of fracture should consider using bisphosphonates.

Low bone mineral density is associated with fatty liver disease and respiratory illness in a pediatric mortality sample

This study finds that fatty liver disease is associated with low bone density in a pediatric mortality sample. Since non-alcoholic fatty liver disease has increased in prevalence over the past few decades among children, a better understanding of the disease's impacts on bone health is of significance to clinicians.

PURPOSE

Chronic illness leads to decreased bone modeling and remodeling. This can be especially problematic during childhood and adolescence, since the majority of an individual's peak bone mass is achieved by the age of 20. In this study, we examine relationships between chronic illness and low bone mineral density (BMD) in a pediatric mortality sample (aged 0.5 to 20.9 years) from New Mexico. We also test whether low BMD is related to decelerated linear growth by examining its relationship to growth stunting and arrest (Harris lines).

METHODS

Hounsfield units (HU), a proxy for trabecular BMD, were obtained at the fourth lumbar vertebra and the femoral neck from postmortem CT scans. Linear regression was used to examine associations between z-standardized HU and age, sex, medical conditions, Harris lines, and growth stunting.

RESULTS

We find that lumbar HU is significantly lower for individuals with fatty liver disease and respiratory illness; femoral HU is significantly lower in individuals with Harris lines.

CONCLUSION

The mechanisms of low BMD in individuals with fatty liver disease and respiratory illness are likely multifactorial and involve vitamin D deficiency (malnutrition, malabsorption), systemic inflammation, and sedentary lifestyles. However, better awareness of this relationship can provide clinicians with the ability to introduce nutritional and behavioral interventions early to mitigate deleterious effects on bone. Harris lines, on the other hand, mark temporary growth cessation due to physiological stress followed by a rapid resumption of growth. Low BMD in these individuals may be due to bone mineralization lagging behind relatively rapid linear growth.

Risk factors associated with low bone mineral density in children with idiopathic scoliosis: a scoping review

BACKGROUND

Children with idiopathic scoliosis (IS) have a high risk of osteoporosis and IS with low bone mineral density (BMD) are susceptible to curve progression. This review aims to explore the risk factors of low BMD in children with IS.

METHODS

Studies were retrieved from 5 databases that were published up to January 2022. Search terms are keywords in titles or abstracts, including subject headings related to "Scoliosis", "Bone Mineral Density", and "Risk Factors". Observational studies on risk factors of low BMD in children with IS were enrolled in this review. The number of studies, sample size, outcome measures, research type, endocrine, and lifestyle-related factors, gene/signal pathway, and other contents were extracted for qualitative analysis.

RESULTS

A total of 56 studies were included in this scoping review. Thirty studies involved genetic factors that may affect BMD, including the Vitamin-D receptor gene, RANK/RANKL signal pathway, the function of mesenchymal stem cells, Runx2, Interleukin-6 (IL-6), and miR-145/β-catenin pathway. Eight studies mentioned the influence of endocrine factors on BMD, and the results showed that serum levels of IL-6, leptin and its metabolites, and ghrelin in children with IS were different from the age-matched controls. In addition, there were 18 articles on lifestyle-related factors related to low BMD in children with IS, consisting of physical activity, calcium intake, Vitamin D level, and body composition.

CONCLUSIONS

Genetic, endocrine, and lifestyle-related factors might relate to low BMD and even osteoporosis in IS. To prevent osteoporosis, the effectiveness of regular screening for low BMD risk factors in children with IS needs to be investigated. Additionally, clear risk factors suggest strategies for bone intervention. Future studies should consider the effectiveness of calcium and vitamin D supplements and physical activity in BMD improvement.

Comparison of early atherosclerosis markers in children with Celiac disease and their healthy peers

Purpose: We aimed to evaluate carotid intima-media thickness (cIMT) and epicardial adipose tissue thickness (EATT) concurrently as early atherosclerotic markers in pediatric patients with Celiac disease. Materials and Methods: Patients with Celiac disease (n=54) and healthy peers (n=54) aged 5-18 years were enrolled in this cross-sectional study. Patients who followed gluten free diet at least the past 12 months were included. Anthropometric and biochemical measurements were performed. cIMT and EATT were measured by echocardiography and compared between the patient and control groups. Results: Body mass index (17.4±3.0 vs. 18.4±3.1 kg/m2), blood pressure (systolic: 100 (85-120) vs. 100 (80-100) mmHg; diastolic: 60 (40-90) vs. 70 (40-90) mmHg), and lipid profile (total cholesterol: 144.6±30.2 vs. 150.8±22.6 mg/dL; triglycerides: 71.5 (27-178) vs. 92.5 (34-203) mg/dL) were not different between the patient and control groups, while there were significant differences in cIMT and EATT. The patient group had higher cIMT (0.50±0.07 vs. 0.45±0.04 mm) and EATT (5.68±0.90 vs. 4.22±0.76 mm) than the control group. The risk of vitamin D insufficiency was 2.68 times higher in the patient group (95% CI=1.19-6.03). Conclusions: Children with Celiac disease had higher cIMT and EATT than healthy peers. cIMT and/or EATT measurements by echocardiography may present as a reliable and easy method to investigate subclinical atherosclerosis in children with Celiac disease.

A systematic review and meta-analysis of pediatric normative peripheral quantitative computed tomography data

BACKGROUND

Peripheral-quantitative computed tomography (pQCT) provides an intriguing diagnostic alternative to dual-energy X-ray absorptiometry (DXA) since it can measure 3D bone geometry and differentiate between the cortical and trabecular bone compartments.

OBJECTIVE

To investigate and summarize the methods of pQCT image acquisition of in children, adolescents and/or young adults (up to age 20) and to aggregate the published normative pQCT data.

EVIDENCE ACQUISITION

A literature search was conducted in MEDLINE and EMBASE from 1947 to December 2020. Quality of the included articles was assessed using Standards for Reporting of Diagnostic Accuracy (STARD) scoring system and United States Preventative Services Task Force (USPSTF) Study Design Categorization. Seven articles, encompassing a total of 2134 participants, were aggregated in the meta-analysis. Due to dissimilar age groups and scan sites, only seven pQCT parameters of the 4% radius, 4% tibia and 38% tibia were analyzed in this meta-analysis.

EVIDENCE SYNTHESIS

The overall fixed-effect estimates of trabecular vBMD of the 4% radius were: 207.16 (201.46, 212.86), mg/cm3 in 8 to 9 year-old girls, 210.42 (201.91, 218.93)in 10 to 12 year-old girls, 226.99 (222.45, 231.54) in 12 to 13 year-old girls, 259.97 (254.85, 265.10) in 12 to 13 year-old boys and 171.55 (163.41,179.69) in 16 to 18 year-old girls. 21 of 54 (38.9%) primary papers received a 'good' STARD quality of reporting score (<90 and 70 ≥ %) (mean STARD score of all articles = 69.4%). The primary articles of this review had a 'good' level USPSTF study design categorization. However, most of the normative data in these articles were non-comparable and non-aggregable due to a lack of standardization of reference lines, acquisition parameters and/or age at acquisition.

CONCLUSION

There is not sufficient evidence to suggest that pQCT is appropriately suited for use in the pediatric clinical setting. Normative pediatric data must be systematically derived for pQCT should it ever be a modality that is used outside of research.

CLINICAL IMPACT

We demonstrate the need for normative pQCT reference data and for clinical guidelines that standardize pediatric acquisition parameters and delineate its use in pediatric settings.

Analysis of the Association between Fat Mass Distribution and Bone Mass in Chinese Male Adolescents at Different Stages of Puberty

Background: Bone mineral acquisition during adolescence is crucial for maximizing peak bone mass. Fat mass (FM) and bone mass are closely related. This study investigated the association of FM distribution with bone mass in Chinese male adolescents. Method: A total of 693 male adolescents aged 10–18 years were recruited from a secondary school in Jiangmen, China. Their bone mass and body composition were measured by quantitative ultrasound and bioelectrical impedance analysis, respectively. The associations of the measures of fat distribution with bone parameters, i.e., broadband ultrasound attenuation, speed of sound (SOS), and stiffness index (SI), were analyzed using multiple linear regression. Age, height, body mass index, stage of puberty, physical activity, sedentary behavior, dietary energy intake, and dietary calcium and vitamin D intake were adjusted in the model. Further subgroup analyses of prepubertal and pubertal participants were conducted. Results: The measures of fat distribution showed negative associations with SOS and SI in total subjects (p < 0.010). In prepubertal boys, the measures of fat distribution were only associated with SOS (β = −0.377 to −0.393, p < 0.050). In pubertal boys, the measures of fat distribution had associations with all bone parameters (β = −0.205 to −0.584, p < 0.050). The strongest association was between trunk FM and SOS (β = −0.584, p < 0.001). Conclusion: This study supported that the measures of fat distribution were negatively associated with bone parameters in Chinese male adolescents. Trunk FM had the strongest association with bone parameter. These associations appear to be stronger in pubertal boys than in prepubertal boys.

Vitamin D supplementation for children with cancer: A systematic review and consensus recommendations

Background

Prevalent vitamin D deficiency (VDD) and low bone mineral density (BMD) have led to vitamin D supplementation for children with cancer, regardless vitamin D status. However, it remains unsettled whether this enhances bone strength. We sought to address this issue by carrying out a systematic review of the literature.

Methods

We conducted a literature search using PubMed, Embase, and Cochrane databases. Studies including children up to 5 years after cancer therapy were assessed for the association between 25‐hydroxyvitamin D (25OHD) levels and BMD Z‐scores or fractures, and the effect of vitamin D supplementation on BMD or fractures. Evidence quality was assessed using the GRADE methodology.

Results

Nineteen studies (16 observational and 3 interventional, mainly involving children with hematologic malignancies) were included. One study which analyzed 25OHD as a threshold variable (≤10 ng/ml) found a significant association between 25OHD levels and BMD Z‐scores, while 25OHD as a continuous variable was not significantly associated with BMD Z‐scores in 14 observational studies. We found neither a significant association between lower 25OHD levels and fractures (2 studies), nor between vitamin D (and calcium) supplementation and BMD or fracture frequency (3 studies) (very low quality evidence).

Conclusion

There is a lack of evidence for an effect of vitamin D (and calcium) supplementation on BMD or fractures in children with cancer. Further research is needed; until then, we recommend dietary vitamin D/calcium intake in keeping with standard national guidelines, and periodic 25OHD monitoring to detect levels <20 ng/ml. Vitamin D/calcium supplementation is recommended in children with low levels, to maintain levels ≥20 ng/ml year‐long.

Evaluation of bone metabolism in children with cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) bone disease (CFBD) has attracted considerable recent interest from researchers, although several aspects of CFBD pathophysiology remain poorly understood. The objective of this research was to investigate CFBD in children with CF and its relation to clinical and bone metabolism markers.

METHODS

In a prospective observational study of 68 patients with CF and 63 healthy controls, we studied bone turnover biomarkers and bone mineral density (BMD). The biomarkers included osteocalcin, total-alkaline phosphatase, bone-alkaline phosphatase, N-terminal propeptide of type-1-procollagen, osteoprotegerin (OPG), interleukine-6, tumor necrosis factor alpha (TNF-α), type-1-collagen cross-linked C-telopeptide (CTX), parathormone (PTH), 25-vitamin D, 1,25-vitamin D, calcium and phosphorus. BMD was examined in lumbar spine, comparing two healthy Spanish populations. Two regression analyses were applied to any significant associations to evaluate predictors of BMD and of CF, expressed as odds ratios (OR) with 95% confidence intervals.

RESULTS

After adjusting for age, sex, and height Z-score, gains in BMD LS in children and adolescents (6-16 years) with CF were not less than in healthy reference population. Patients with CF showed significant associations with different bone turnover biomarkers. Age, gender, body mass index, PTH, CTX and OPG were significant predictors of BMD (R² = 0.866, p < 0,001). Moreover, we found that PTH (OR = 1.070; 95% CI 1.019-1.123), and TNFα (OR = 2.173; 95% CI 1.514-3.118) were significantly linked to CF, and calcium (OR = 0.115; 95% CI 0.025-0.524), 1,25-vitamin D (OR = 0.979; 95% CI 0.962 0.996) and OPG (OR = 0.189; 95% CI 0.073-0.489) were significant reduced.

CONCLUSION

A normal bone mineral density along with altered remodeling was found in CF patients with a normal nutritional status and without acute lung disease.

Efficacy and safety of intravenous pamidronate infusion for treating osteoporosis in children and adolescents

PURPOSE

Osteoporosis is a skeletal disorder characterized by reduced bone mass that results in increased risk of fractures. Pediatric osteoporosis can be caused by monogenic diseases, chronic diseases, and/or their treatment. This study was performed to investigate the effect of pamidronate infusion on osteoporosis in children and adolescents.

METHODS

This study included 13 unrelated pediatric patients (10 males and 3 females) whose bone mineral density (BMD) z-score was &lt;-2.0. Pamidronate was administered intravenously at a dosage of 1 mg/kg for 3 consecutive days every 4 months. Clinical and biochemical findings were reviewed retrospectively. The BMD values of the lumbar spine and femoral neck were assessed by dual energy x-ray absorptiometry at baseline and annually.

RESULTS

The underlying diseases were immobilization (62%), inflammatory bowel disease (23%), protein-losing enteropathy (8%), and idiopathic juvenile osteoporosis (8%). The mean age at the start of treatment was 12.7±4.3 years. Duration of treatment ranged from 12-50 months. The baseline height-standard deviation score (SDS) and weight-SDS were -2.01±2.08 and -2.60±1.62, respectively. The lumbar spine BMD z-scores improved significantly after 1 year of pamidronate treatment, but the femoral neck BMD z-scores did not. However, both z-scores had significantly increased by the end of treatment.

CONCLUSION

This study demonstrated that pamidronate treatment increased BMD in pediatric patients with osteoporosis with no significant adverse events. Further studies are required to better define the long-term efficacy and safety of pamidronate therapy in a large number of pediatric patients.

Advances in the occurrence and biotherapy of osteoporosis

Osteoporosis (OP) is a bone metabolic disease, is characterized by degeneration of bone structure and decreased bone mass. It happens in more than 1/3 women and 1/5 men of over than 50 years old, which affects the health and lives of people. The main mechanism of OP is mainly that the dynamic balance between the bone formation and resorption is broken, so that bone resorption is more than bone formation. It is prone to result in bone metabolism disorder. There are many precipitating factor such as elder age, low hormone level, genetic factors and bad hobbies. At the same time, the occurrence of the OP and its complications has different degrees of impact on people's quality of life. Based on the current understanding of the OP, we summarized the etiology, current clinical drugs and potential targeting therapy for OP. Although the research have made many progress in explore what is the novel mechanism and how to improve the effect, there are still many problems in the treatment method that limit its application prospects and need to be solved. In this review, we mainly focus on the mechanism of OP and related research on the targeted treatment of OP. Hopefully, our summary will provide a reference to develop some novel strategies for the target therapy of OP.

Metabolic bone disease in children with intestinal failure is not associated with the level of parenteral nutrition dependency

BACKGROUND & AIMS

Children on long-term home parenteral nutrition (HPN) are at increased risk of suboptimal growth and metabolic bone disease (MBD) i.e. decreased bone mineral density (BMD). The aims of this cross-sectional study were to assess growth and bone health in children on long term HPN and to identify risk factors for MBD.

METHODS

Children above the age of 5 years, stable on HPN for more than 2 years were included. Medical files were reviewed retrospectively and included demographics, gestational age, birth weight and height, indication for PN, age at PN start, duration of PN, number of weekly PN infusions, weight-for-age and height-for-age (SD), body mass index (BMI, kg/m²) as well as blood and urine analyses at the time of Dual X-ray absorptiometry (DXA) measurements. All BMD values were adjusted to statural age which corresponds to the 50th percentile of height. Growth failure (height-for-age ≤ -2SD) and MBD (at least one BMD measurement ≤ -2SD) were analyzed according to the indication of PN, duration of PN and PN dependency index (PNDI) by comparing means and performing logistic regression analysis. PNDI is the ratio of non-protein energy intake in HPN to resting energy expenditure using Schofield equations.

RESULTS

Forty children were assessed at 12.4 ± 4.5 years of age. Mean age at PN start was 1.1 ± 3.6 y (median 0.5). The indications for PN were short bowel syndrome (SBS, n = 21), chronic intestinal pseudo-obstruction syndrome (CIPOS, n = 10) and congenital enteropathies (CE, n = 9). The mean number of PN perfusions was 6 ± 1/week. PNDI was 110 ± 30%. The mean serum level of 25-OHD3 was suboptimal at 26.5 ± 9.1 ng/mL (66.2 ± 22.8 nmol/L). The mean concentrations of calcium, phosphorus, and parathyroid hormone (PTH) were in the normal ranges. Eight children (20%) had PTH levels above normal with low 25-OHD3 levels. The mean weight-for-age and height-for-age Z-scores SDS were 0.4 ± 0.9 and -0.5 ± 1.1 respectively. The actual height was lower than genetic target height (p < 0.001). The BMD Z-scores, adjusted to the 50th percentile of height, of the spine, the left femur and the whole body were: -1.1 ± 1.7, -1.2 ± 1.5 and -1.5 ± 1.8 SDS respectively. Children with CE had significantly lower BMD values than those with SBS and CIPOS (p = 0.01). Only two children had bone fractures after a mild trauma (5%).

CONCLUSIONS

All children on long-term PN, are at risk of low BMD. High dependency on PN (PNDI>120%) and very long-term PN (>10 years) do not appear to increase the risk of growth failure nor MBD. PN-related bone fractures were rare. Close follow-up remains mandatory.

The Prevalence of Abnormalities in the Pediatric Spine on MRI: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

The aim of this study was to provide an overview of the prevalence of reported musculoskeletal abnormalities on magnetic resonance imaging (MRI) of the pediatric spine.

SUMMARY OF BACKGROUND DATA

Back pain is a common complaint and significant health issue, already in children. Several studies have investigated musculoskeletal abnormalities of the pediatric spine as possible cause of low back pain (LBP). However, it is not clear which abnormalities are the most prevalent among children.

METHODS

A systematic literature search on the prevalence of musculoskeletal spinal abnormalities on MRI in children was conducted in the Embase, Medline Ovid, and Cochrane CENTRAL databases. Risk of bias (RoB) was assessed using a checklist based on the Downs and Black checklist. General information on study and patient characteristics and the prevalence of spinal abnormalities were extracted from the studies. Prevalence data were presented in three subgroups: nonathletes without LBP, participants with LBP, and athletes. Prevalence data of the most reported abnormalities were pooled using random-effects proportion meta-analysis. The study protocol was prospectively registered in PROSPERO (CRD42017080543).

RESULTS

The search resulted in 16,783 articles, of which 31 articles (2373 participants) were included in this systematic review. Two-thirds of the studies had a low RoB. The pooled prevalence in nonathletes without LBP, participants with LBP, and athletes without LBP was respectively 22%, 44%, and 22% for disc degeneration, 1%, 38%, and 13% for herniated discs, 5%, 22%, and 11% for endplate changes, and 0%, 30%, and 6% for pars fractures.

CONCLUSION

Disc degeneration, herniated discs, endplate changes, and spondylolysis are the most reported spinal abnormalities on MRI in children in literature. Spinal abnormalities seen in adults are already prevalent in children with LBP, with the highest prevalence for disc degeneration and herniated discs.

LEVEL OF EVIDENCE

2.

Guidelines for the management of children at risk of secondary bone fragility: Expert opinion of a French working group

The current French national guidelines were elaborated by a working group consisting of experts in the field of pediatric endocrinology, rheumatology, hepatogastroenterology, nephrology, and pneumology. A systematic search was undertaken of the literature published between 2008 and 2018 and indexed in PubMed. The recommendations developed were then validated by an external evaluation group comprising representatives from the various highly specialized fields in pediatrics, representatives of the societies and groups supporting the development of the guidelines, and representatives of different healthcare professions. The objective of these guidelines was to detail the current optimal management of children at risk of secondary bone fragility.

Medications as a Risk Factor for Fragility Hip Fractures: A Systematic Review and Meta-analysis

Fragility hip fractures and their associated morbidity and mortality pose a global healthcare problem. Several pharmaceutical products have been postulated to alter bone architecture and contribute to fragility hip fractures. We searched four electronic databases from inception to September 2017. Inclusion criteria were the following: (1) adult patients with fragility hip fractures, (2) full text in English, (3) minimum one-year follow-up, and (4) reporting of at least one risk factor. To minimize heterogeneity among the studies, we performed subgroup analyses. Whenever heterogeneity remained significant, we employed random effect meta-analysis for data pooling. Thirty-eight studies were included, containing 1,244,155 subjects and 188,966 cases of fragility hip fractures. Following medications were significantly associated with fragility hip fractures: Antidepressants (OR 2.07, 95% CI 1.98-2.17), antiparkinsonian drugs (OR 2.21, 95% CI 1.15-4.24), antipsychotic drugs (OR 2.0, 95% CI 1.50-2.66), anxiolytic drugs (OR 1.44, 95% CI 1.19-1.75), benzodiazepines (OR 1.84, 95% CI 1.26-2.69), sedatives (OR 1.33, 95% CI 1.14-1.54), systemic corticosteroids (OR 1.65, 95% CI 1.37-1.99), H₂ antagonists (OR 1.21, 95% CI 1.18-1.24), proton pump inhibitors (OR 1.41, 95% CI 1.16-1.71), and thyroid hormone (OR 1.29, 95% CI 1.13-1.47). Hormone replacement therapy with estrogen (HRT) was associated with decreased risk of hip fracture (OR 0.80, 95% CI 0.65-0.98). There are several medications associated with sustaining a fragility hip fracture. Medical interventions should be considered for patients on these medications, including information about osteoporosis and fracture prevention.

Birth weight associated with dual energy X-ray absorptiometry-determined muscle-bone unit in young healthy women from the Nutritionists' Health Study

Muscle and bone have been considered a functional unit that grows together early in life, deteriorates with aging, and can cause osteosarcopenia. Due to its importance in public health, detecting risk factors in early life is desirable. This study examined whether birth weight (BW) was associated with muscle-bone unit using dual energy X-ray absorptiometry (DXA) parameters in young women from the Nutritionists' Health Study (NutriHS), a cohort study of undergraduates and Nutrition graduates. This cross-sectional analysis included 170 young healthy women who answered early life events-questionnaire, and had anthropometric, muscle tests and DXA-determined body composition and bone densitometry (iDXA-Lunar®). A blood sample was obtained for a subsample of 148 participants. Appendicular skeletal muscle mass index (ASMI) was calculated. BW was categorized in quartiles (BWq) and variables of interest compared by ANOVA. Associations of BWq with calf circumference (CC), handgrip, muscle performance tests, ASMI, bone mineral density and content (BMD and BMC), and plasma glucose, lipids, insulin, and 25-hydroxyvitamin D were performed using multiple linear regression and directed acyclic graph-recommended adjustments. Mean values of age, body mass index, and BW were 23.0 years (20.0-28.0), 22.9 ± 2.9 kg/m2, and 3199 ± 424 g, respectively. Comparing variables across BWq, significant differences in CC, handgrip, ASMI, and total body BMC were detected. Regression models adjusted for confounders showed associations of BWq with CC (β = 0.72, p = 0.005), handgrip (β = 1.53, p = 0.001), ASMI (β = 0.16, p = 0.022), total body BMC (β = 64.8, p = 0.005), total femur BMC (β = 0.70, p = 0.041), total body BMD (β = 0.02, p = 0.043), and lumbar spine BMD (β = 0.03, p = 0.028). We conclude that BW is associated with muscle-bone unit using DXA-parameters in Brazilian young healthy women from the NutriHS, suggesting a role for intrauterine environment for musculoskeletal health.

Effects of vitamin D and estrogen receptor polymorphisms on bone mineral density in adolescents with anorexia nervosa

Background Anorexia nervosa (AN) is a serious eating disorder that is associated with decreased bone mineral density (BMD) and greater lifetime risk for fractures. The aim of this study was to determine the correlation between BMD and genetic polymorphisms in AN. Methods This case-control study analyzed vitamin D receptor (VDR) (VDRBsml, VDRFokl) and estrogen receptor (ESR) (ESR1Xbal, ESR1Pvull) polymorphisms in 45 adolescents diagnosed with AN and 46 age-matched healthy controls. BMD values of the AN group were classified as low or normal, and polymorphisms were compared between cases and controls. The effects of body mass index (BMI), duration of disease and amenorrhea on BMD were also evaluated. Results In girls with AN, a positive effect of the bb genotype of VDRBsmI polymorphism on femur Z-scores (p = 0.103) and of the Ff genotype of VDRFokI polymorphism on vertebra Z-scores (p = 0.097) was observed. In boys with AN, a positive effect of the Ff genotype of VDRFokI polymorphism on vertebra BMD (g/cm2) was detected (p = 0.061). No association was detected between ESR polymorphisms. An inverse relationship was observed between BMD and duration of illness and amenorrhea. A direct relationship was detected between BMD and BMI. Conclusions Specific VDR gene polymorphism genotypes may have positive effects on BMD in patients with AN. Additionally, the lack of association between ESR gene polymorphisms on BMD could be attributed to the low estrogen status of the patient.

Chronic dietary supplementation with kynurenic acid, a neuroactive metabolite of tryptophan, decreased body weight without negative influence on densitometry and mandibular bone biomechanical endurance in young rats

Kynurenic acid (KYNA) is a neuroactive metabolite of tryptophan. KYNA naturally occurs in breast milk and its content increases with lactation, indicating the role of neonatal nutrition in general growth with long-term health effects. KYNA is also an antagonist of ionotropic glutamate receptors expressed in bone cells. The aim of this study was to establish the effects of chronic KYNA supplementation on bone homeostasis in young rats, using mandible as a model bone. Female and male newborn Wistar rats were divided into control and KYNA-administered groups until 60 days of age (25x10¹ mg/L or 25x10² mg/L in drinking water). Hemimandibles were subjected to densitometry, computed tomography analysis and mechanical testing. Rats supplemented with KYNA at both doses showed a decrease in body weight. There were no effects of KYNA administration and mandible histomorphometry. In males, a significant quadratic effect (P < 0.001) was observed in the densitometry of the hemimandible, where BMD increased in the group supplemented with 2.5x10¹ mg/L of KYNA. Analysis of mechanical tests data showed that when fracture forces were corrected for bone geometry and rats body weight the improvement of bone material properties was observed in male and female rats supplemented with lower dose of KYNA. This study showed that chronic supplementation with KYNA may limit weight gain in the young, without adversely affecting the development of the skeleton.

Clinical and Molecular Characterization of Familial Exudative Vitreoretinopathy Associated With Microcephaly

PURPOSE

Familial exudative vitreoretinopathy (FEVR) is a rare finding in patients with genetic forms of microcephaly. This study documents the detailed phenotype and expands the range of genetic heterogeneity.

DESIGN

Retrospective case series.

METHODS

Twelve patients (10 families) with a diagnosis of FEVR and microcephaly were ascertained from pediatric genetic eye clinics and underwent full clinical assessment including retinal imaging. Molecular investigations included candidate gene Sanger sequencing, whole-exome sequencing (WES), and whole-genome sequencing (WGS).

RESULTS

All patients had reduced vision and nystagmus. Six were legally blind. Two probands carried bi-allelic LRP5 variants, both presenting with bilateral retinal folds. A novel homozygous splice variant, and 2 missense variants were identified. Subsequent bone density measurement identified osteoporosis in one proband. Four families had heterozygous KIF11 variants. Two probands had a retinal fold in one eye and chorioretinal atrophy in the other; the other 2 had bilateral retinal folds. Four heterozygous variants were found, including 2 large deletions not identified on Sanger sequencing or WES. Finally, a family of 2 children with learning difficulties, abnormal peripheral retinal vasculogenesis, and rod-cone dystrophy were investigated. They were found to have bi-allelic splicing variants in TUBGCP6. Three families remain unsolved following WES and WGS.

CONCLUSIONS

Molecular diagnosis has been achieved in 7 of 10 families investigated, including a previously unrecognized association with LRP5. WGS enabled molecular diagnosis in 3 families after prior negative Sanger sequencing of the causative gene. This has enabled patient-specific care with targeted investigations and accurate family counseling.

The Association between First Fractures Sustained during Childhood and Adulthood and Bone Measures in Young Adulthood

OBJECTIVE

To describe the association between fractures sustained at different stages of growth and bone measures in early adulthood.

STUDY DESIGN

Participants (n = 201) in southern Tasmania were at birth at a higher risk of sudden infant death syndrome; they were followed to age 25. Outcomes were areal bone mineral density at the spine, hip, and total body (by dual-energy x-ray absorptiometry) and trabecular and cortical bone measures at the radius and tibia (by high-resolution peripheral quantitative computed tomography). Fractures were self-reported and confirmed by radiographs at 8, 16, and 25 years of age. Multivariable linear regression was used to analyze the association of the occurrence of prepubertal (<9 years of age), pubertal (9-16 years of age), and postpubertal (17-25 years of age) fractures with all bone measures.

RESULTS

Over 25 years, 99 participants had at least 1 fracture. For high-resolution peripheral quantitative computed tomography measures at age 25, prepubertal fractures were negatively associated with cortical and trabecular volumetric bone mineral density and most microarchitecture measures at both the tibia and radius. Prepubertal fractures had a significant association with smaller increase of areal bone mineral density from age 8 to 16 years and at 25 years of age compared with participants with no fractures. Pubertal fractures had no association with any bone measures and postpubertal fractures were only associated with a lower trabecular number at the tibia.

CONCLUSIONS

Prepubertal fractures are negatively associated with areal bone mineral density increases during growth and high-resolution peripheral quantitative computed tomography bone measures in young adulthood. There is little evidence that fractures occurring from age 8 years onward with bone measures in young adulthood, implying that prepubertal fractures may be associated with bone deficits later in life.

Prospective study of growth and bone mass in Swedish children treated with the modified Atkins diet

PURPOSE

The modified Atkins diet (MAD) is a less restrictive treatment option than the ketogenic diet (KD) for intractable epilepsy and some metabolic conditions. Prolonged KD treatment may decrease bone mineralization and affect linear growth; however, long-term studies of MAD treatment are lacking. This study was designed to assess growth, body composition, and bone mass in children on MAD treatment for 24 months.

METHODS

Thirty-eight patients, mean age (SD) 6.1 years (4.8 years), 21 girls, with intractable epilepsy (n = 22), glucose transporter type 1 deficiency syndrome (n = 7), or pyruvate dehydrogenase complex deficiency (n = 9) were included. Body weight, height, body mass index (BMI), bone mass, and laboratory tests (calcium, phosphorus, magnesium, alkaline phosphatase, cholesterol, 25-hydroxyvitamin D, insulin-like growth factor-I and insulin-like growth factor binding protein 3) were assessed at baseline and after 24 months of MAD treatment.

RESULTS

Approximately 50% of the patients responded with more than 50% seizure reduction. Weight and height standard deviation score (SDS) were stable over 24 months, whereas median (minimum - maximum) BMI SDS increased from 0.2 (-3.3 to 4.5) to 0.7 (-0.9 to 2.6), p < 0.005. No effects were observed for bone mass (total body, lumbar spine and hip) or fat mass.

CONCLUSIONS

The MAD was efficient in reducing seizures, and no negative effect was observed on longitudinal growth or bone mass after MAD treatment for 24 months.

Whole-body and segmental analysis of body composition in adult males with achondroplasia using dual X-ray absorptiometry

Achondroplasia is a condition characterized by a genetic mutation affecting long bone endplate development. Current data suggests that the bone mineral content (BMC) and bone mineral density (BMD) of achondroplasic populations are below age matched individuals of average stature (controls). Due to the disproportionate limb-to-torso length compared to controls however, the lower BMC and BMD may be nullified when appropriately presented. The aim of this study was to measure whole-body and segmental body composition in adult males with achondroplasia (N = 10, 22 ±3 yrs), present data relative to whole-body and whole-limb values and compare all values to age matched controls (N = 17, 22 ±2 yrs). Dual X-ray absorptiometry (DEXA) was used to measure the in vivo mass of the whole-body and 15 segments, from which BMD, BMC, fat free mass (FFM) and body fat mass were measured. BMC of lumbar vertebrae (L1-4) was also measured and presented as a volumetric BMD (BMDVOL). The achondroplasic group had less BMC, BMD and FFM, and more body fat mass than controls as a whole-body measure. The lower achondroplasic BMC and BMD was somewhat nullified when presented relative to whole-body and whole-limb values respectively. There was no difference in lumbar BMDVOL between groups. Whole-body BMD measures presented the achondroplasic group as 'osteopenic'. When relative to whole-limb measures however, achondroplasic BMD descriptions were normal. Further work is needed to create a body composition database for achondroplasic population's, or for clinicians to present achondroplasic body composition values relative to the whole-limb.

Siglec-15-targeting therapy increases bone mass in rats without impairing skeletal growth

The treatment of juvenile osteoporosis has not been established due to a lack of data regarding the efficacy and adverse effects of therapeutic agents. The possible adverse effects of the long-term use of antiresorptive therapies on skeletal growth in children is of particular concern. Sialic acid-binding immunoglobulin-like lectin 15 (Siglec-15) is an immunoreceptor that regulates osteoclast development and bone resorption, and its deficiency suppresses bone remodeling in the secondary spongiosa, but not in the primary spongiosa, due to a compensatory mechanism of osteoclastogenesis. This prompted us to develop an anti-Siglec-15 therapy for juvenile osteoporosis because most anti-resorptive drugs have potential adverse effects on skeletal growth. Using growing rats, we investigated the effects of an anti-Siglec-15 neutralizing antibody (Ab) on systemic bone metabolism and skeletal growth, comparing this drug to bisphosphonate, a first-line treatment for osteoporosis. Male 6-week-old F344/Jcl rats were randomized into six groups: control (PBS twice per week), anti-Siglec-15 Ab (0.25, 1, or 4 mg/kg every 3 weeks), and alendronate (ALN) (0.028 or 0.14 mg/kg twice per week). Treatment commenced at 6 weeks of age and continued for the next 6 weeks. Changes in bone mass, bone metabolism, bone strength, and skeletal growth during treatment were analyzed. Both anti-Siglec-15 therapy and ALN increased bone mass and the mechanical strength of both the femora and lumbar spines in a dose-dependent manner. Anti-Siglec-15 therapy did not have a significant effect on skeletal growth as evidenced by micro-CT-based measurements of femoral length and histology, whereas high-dose ALN resulted in growth retardation with histological abnormalities in the growth plates of femurs. This unique property of the anti-Siglec-15 Ab can probably be attributed to compensatory signaling for Siglec-15 inhibition in the primary spongiosa, but not in the secondary spongiosa. Thus, anti-Siglec-15 therapy could be a safe and effective for juvenile osteoporosis.

Serum 25-hydroxyvitamin D and bone mineral density among children and adolescents in a Northwest Chinese city

Although vitamin D is essential for bone health, little is known about prevalence of vitamin D deficiency and low bone mineral density (BMD) among children, especially those in developing countries. It also remains unclear whether serum 25-hydroxyvitamin D [25(OH)D] is associated with BMD among children. We investigated these questions among children and adolescents in Yinchuan (latitude: 38° N), Ningxia, an economically underdeveloped province in Northwest China. A total of 1582 children (756 boys and 826 girls), aged 6-18 years, were recruited from schools using the stratified random sampling method in fall 2015. Serum 25(OH)D concentrations were measured by enzyme-linked immunosorbent assay, and BMD was quantified by dual-energy X-ray absorptiometry. Vitamin D deficiency (defined as serum 25(OH)D ≤ 37.5 nmol/L) was present in 35.5% of study subjects. There were no clear patterns of differences in serum 25(OH)D concentrations across the four age groups compared (6-9 years, 10-13 years, 14-16 years, and 17-18 years). The prevalence of low total body less head (TBLH) BMD (defined as a Z-score of ≤ -2.0 standard deviations away from the mean BMD values of the Chinese pediatric reference population) among children examined was 1.8% and was not significantly different among the four age groups considered. Linear regression analysis revealed that age, weight, and height were significantly and positively associated with TBLH BMD and that the strongest determinant of TBLH BMD was age in boys and weight in girls. There were no significant correlations between serum 25(OH)D concentrations and BMD obtained for total body and at various skeletal sites (r ranged from -0.005 to 0.014) regardless of whether children evaluated were sufficient, insufficient, or deficient in vitamin D. In conclusion, more than one-third of children and adolescents in a Northwest Chinese city were deficient in vitamin D but only <2% of them developed low BMD.

Self-efficacy of osteoporosis preventive behaviors and its predictors in Iranian adolescents

INTRODUCTION

Almost all the bone mass in females is accumulated during adolescence and especially in the years immediately following menstruation. Self-efficacy plays an important role in moderating the relationship between knowledge and behavior. This study aimed to determine the self-efficacy of osteoporosis preventive behaviors and its predictors in female high school students.

METHODOLOGY

This descriptive-analytical cross-sectional study was conducted on 330 female high school students in Saveh, Iran during 2016-2017. A two-stage cluster sampling method was used to select the participants. Data were collected using a socio-demographic questionnaire, the Osteoporosis Knowledge Test (OKT) and the Osteoporosis Self-Efficacy Scale (OSES). A general linear model was used to determine the self-efficacy predictors of osteoporosis preventive behaviors.

RESULTS

The mean [standard deviation (SD)] of the total OKT score was 11.08 (4.08) of attainable range from 0 to 32. The mean (SD) of the total OSES score was 121.97 (37.36) of attainable range from 0 to 200. The mean (SD) of the exercise and calcium subscales of OSES were 58.39 (22.56) and 63.57 (21.02), respectively. There were significant relationships between the total OKT score with the total OSES score (r = 0.16, p = 0.003) and its subscales, including exercise (r = 0.16, p = 0.002) and calcium (r = 0.11, p = 0.03) scores. According to the adjusted general linear model, the variables of economic status, educational level and osteoporosis knowledge were predictors of the self-efficacy in the studied students.

CONCLUSION

Findings suggested that most of the students had moderate levels of knowledge and self-efficacy regarding osteoporosis preventive behaviors; therefore, improving the knowledge and self-efficacy of this group can play a significant role in promoting their health.

Primary Care and Emergency Department Management of the Patient With Duchenne Muscular Dystrophy

Primary care providers (PCPs) are usually the first point of contact with the health care system for patients with Duchenne muscular dystrophy (DMD), and patients often present to emergency departments in which providers have little experience in dealing with this condition. With this article, we give primary care and emergency medicine providers a background in the common issues that affect people with DMD. By acquiring some specialized knowledge about the multisystem medical complications of DMD and by applying general principles of primary care, such as timely immunization, anticipatory safety counseling, behavioral screening, and routine nutritional and developmental assessments, the PCP can be a valued and effective medical provider to patients with DMD. The PCP can provide access to and effective coordination among the patient's specialty caregivers. Moreover, the PCP can become a trusted advisor to the patient and his family about important medical decisions, as well as issues in the psychosocial, behavioral, and educational domains. This article also contains a "pocket guide" used to assess and manage common urgent medical problems that cause patients with DMD to seek care in the emergency department. With the background information discussed in this article, both PCPs and emergency medicine physicians can skillfully care for patients with DMD in their respective settings, optimizing patient outcomes.

Can radial bone mineral density predict spinal bone mineral density in patients with advanced Duchenne muscular dystrophy?

In advanced Duchenne muscular dystrophy (DMD), patients with high bone fracture risk due to osteoporosis, it is difficult to measure spinal bone mineral density (BMD) because of maintaining proper posture. This study began with the idea that if we diagnose and manage osteoporosis by predicting spinal BMD through easily testable radial BMD, we could prevent fracture and improve quality of life in DMD patients. In 61 DMD patients aged 20 years or older who were admitted to Gangnam Severance Hospital from April 2013 to May 2015, radial BMD and spinal BMD were measured to compare their Z-scores. In 45 patients, the z-score was less than -2.0 in spinal BMD defined as osteoporosis. And the optimal range of Z-score in the radius was -5.2 to -5.0 (sensitivity 78.9%, specificity 71.4%). Only through the radius BMD, spinal BMD can be predicted and we suggest appropriate times for treatments.

Update on bone density measurements and their interpretation in children and adolescents

Following the increased awareness about the central role of the pediatric age in building bone for life, clinicians face more than ever the necessity of assessing bone health in pediatric subjects at risk for early bone mass derangements or in healthy children, in order to optimize their bone mass accrual and prevent osteoporosis. Although the diagnosis of osteoporosis is not made solely upon bone mineral density measurements during growth, such determination can be very useful in the follow-up of pediatric patients with primary and secondary osteoporosis. The ideal instrument would give information on the mineral content and density of the bone, and on its architecture. It should be able to perform the measurements on the skeletal sites where fractures are more frequent, and it should be minimally invasive, accurate, precise and rapid. Unfortunately, none of the techniques currently utilized fulfills all requirements. In the present review, we focus on the pediatric use of dual-energy X-ray absorptiometry (DXA), quantitative computed tomography (QCT), peripheral QCT (pQCT), and magnetic resonance imaging (MRI), highlighting advantages and limits for their use and providing indications for bone densitometry interpretation and of vertebral fractures diagnosis in pediatric subjects.

Assessment of Lactose-Free Diet on the Phalangeal Bone Mineral Status in Italian Adolescents Affected by Adult-Type Hypolactasia

Adult-type hypolactasia (ATH) is a clinical syndrome of primary lactase deficiency. A lactose-free diet is advisable to avoid the symptoms linked to the condition, but this potentially creates problems for optimal bone mineralization due to reduced calcium intake. To evaluate the effect of the lactose-free diet on the bone mineral status (BMS), we compared the phalangeal BMS of adolescents with ATH to that of peers on a normal diet. Also, we analyzed the correlations between BMS and dietary behavior, physical exercise, and calcium and vitamin D intake. A total of 102 cases and 102 healthy controls filled out a diet record and underwent phalangeal Quantitative Ultrasound (QUS). No difference in BMS was observed. The time spent on lactose-free diet (4.8 ± 3.1 years) was inversely correlated to the BMS. More than 98% of cases consumed lactose-free milk, but calcium and vitamin D intake were significantly lower. Calcium intake was correlated to physical exercise but not to BMS. Our results suggest that a lactose-free diet does not affect the phalangeal BMS of adolescents with primary lactase deficiency when their diet includes lactose-free cow’s milk. However, there is still a significantly lower calcium intake than in the population reference. The inverse correlation observed between the BMS and the time spent on a lactose-free diet suggests that a long-term follow-up is advisable.

A New Condition in McArdle Disease: Poor Bone Health-Benefits of an Active Lifestyle

INTRODUCTION-PURPOSE

McArdle disease (muscle glycogen phosphorylase deficiency) is a genetic condition associated with exercise intolerance, but how it affects lean mass (LM) and bone mineral content (BMC) and density (BMD) in patients is unknown. We compared these variables between McArdle patients and age-/sex-matched healthy controls and assessed their potential association with physical activity levels in patients.

METHODS

A case-control, cross-sectional design was used to examine LM, BMC, and BMD by using dual-energy x-ray absorptiometry in 136 young adults of both sexes (36 McArdle patients (33 ± 15 yr) and 103 controls (34 ± 11 yr)). Physical activity was assessed using the International Physical Activity Questionnaire.

RESULTS

McArdle patients had significantly lower LM values in whole-body and regional sites compared with their corresponding controls, whereas no differences were found (except for the trunk) when physically active patients (n = 23) were compared with controls. All bone-related variables were significantly lower in patients than in controls (average difference of 13% for BMC and 7.6% for BMD). By contrast, no significant differences at the lumbar spine, pelvis, and femur sites were found between physically active patients and controls.

CONCLUSIONS

We report on a previously undescribed condition in McArdle patients, poor bone health, which warrants further attention because it can occur in relatively young adults. An active lifestyle can at least partly alleviate this disorder presumably because of its beneficial effect on LM.

Investigating the Prevalence of Low Bone Mass in Children of Southern Iran and Its Associated Factors

BACKGROUND

Improving peak bone mass and bone strength in the first years of life and enhancing it during young adulthood could prevent osteoporosis and fractures in the last years of life. We evaluated the prevalence of low bone mass in the lumbar and femoral neck and its associated factors in southern Iranian children.

METHODS

This is a cross-sectional study on healthy Iranian children aged 9 - 18 years old during 2011 - 2012. Dual energy X-ray absorptiometry (DEXA) was used for measuring bone mineral density (BMD). BMD Z-score ≤ -2 was considered as low. Anthropometric data, physical activity, sun exposure, puberty, and mineral biochemical parameters were assessed. Data were analyzed using SPSS v.15.

RESULTS

477 normal children, including 236 (49.5%) girls and 241 (50.5%) boys, aged 13.8 ± 2.7 years were enrolled. Prevalence of low bone mass (LBM) in the femoral and lumbar region was 10.7% and 18.7%, respectively. The prevalence of LBM in femur of girls is twice more than boys. Fat mass index, BMI Z-score, and physical activity were associated with lumbar low bone mass. BMI Z-score and physical activity were associated with femoral low bone mass.

CONCLUSIONS

High prevalence of low bone mineral density in children 9 to 18 years in south of the country is concerned and is needed to plan for prevention and treatment. BMI-Z score, fat mass index, and physical activity were the 3 most important preventive factors in developing low bone mass in children.

Technique, Safety, and Yield of Bone Biopsies for Histomorphometry in Children

PURPOSE

To evaluate image-guided bone biopsy for bone histomorphometry to assess osteoporosis in children with respect to safety and yield.

MATERIALS AND METHODS

A single-center retrospective review was performed of 79 bone biopsies in 73 patients performed between 2007 and 2015. Biopsies of the iliac bone were performed under general anesthesia, after tetracycline labeling, using a Rochester needle (Medical Innovations International, Inc, Rochester, Minnesota). Ultrasound and fluoroscopic guidance were used in all procedures. Biopsy technique, technical success, safety, and histomorphometry results (complete, incomplete, none) were analyzed.

RESULTS

There were 41 male patients (51.8%). Technical success was achieved in 76/79 (96%) procedures. Of 79 biopsies, 75 (95%) were uneventful. Unplanned overnight observation was required in 3 (minor SIR grade B), and prolonged hospital stay owing to hematoma causing nerve compression pain was required in 1 (major SIR grade D). Complete histomorphometric reports were obtained in 69 (87%) procedures, incomplete reports were obtained in 7 (9%), and no reports were obtained in 3(4%). Incomplete reports were insufficient to provide a definitive diagnosis or guide treatment. Histomorphometry impacted subsequent therapy in 69 (87%) biopsies.

CONCLUSIONS

Image-guided bone biopsy for osteoporosis using the Rochester needle is a valuable and safe technique for establishing the diagnosis of osteoporosis and directing treatment based on histomorphometry results.

Bone mineral density in people living with HIV: a narrative review of the literature

Bone health status is largely absent in South Africa, the main reasons being the absence and cost-effectiveness of specific screening equipment for assessing bone mineral density (BMD). Various risk factors seem to play a role, some of which can be modified to change bone health status. Urbanisation is also a public health concern. Changing nutritional, as well as social behaviour, play integral roles in the prevalence and incidence of decreased BMD. Furthermore, human immunodeficiency virus (HIV) specifically, has a negative impact on BMD and although highly active antiretroviral therapy increases the prognosis for HIV-infected individuals, BMD still seem to decrease further. Dual energy X-ray absorptiometry is considered the gold standard for BMD assessment; however, recent developments have provided more cost-effective screening methods, among which heel quantitative ultrasound appears to be the most widely used in resource limited countries such as South Africa.

Risk Factors for Fractures in Children Hospitalized in Intensive and Intermediate Care Units

BACKGROUND AND OBJECTIVES

Fragility fractures are increasingly recognized in hospitalized children. Our study aim was to identify risk factors for fracture in children hospitalized in intensive and intermediate care units.

METHODS

We conducted a retrospective, case-control study comparing the clinical characteristics of children with fractures (cases) to children without fractures (controls) matched for age, sex, hospital unit, admission quarter and year, ICU length of stay, severity of illness, and resource utilization. Bivariate comparisons and matched multivariable logistic regression modeling were used to determine associations between potential risk factors and fracture.

RESULTS

Median age at fracture for the 35 patients was 5.0 months (interquartile range 2.0 to 10.0 months) and at a comparable interval for the 70 matched controls was 3.5 months (interquartile range 2.0 to 7.0 months). In bivariate analyses, factors associated with fracture included: primary diagnosis of tracheoesophageal fistula, esophageal atresia and stenosis; diagnosis of kidney disease; and per 5-day increase in median cumulative ICU days at risk. In the final model, a respiratory disease diagnosis (odds ratio 3.9, 95% confidence interval 1.1-13.7) and per 5-day increase in median cumulative ICU days at risk (odds ratio 1.3, 95% confidence interval 1.0-1.6) were significant independent risk factors for fracture.

CONCLUSIONS

Children prone to fracture in the hospital are young, medically complex patients who require extended periods of intensive level medical care and potentially life-sustaining treatment modalities. The children who would benefit most from fracture reduction efforts are those with respiratory disease and prolonged ICU stays.

Implications of the FMR1 Premutation for Children, Adolescents, Adults, and Their Families

BACKGROUND AND OBJECTIVES

Given the nature of FMR1 gene expansions, most biological mothers, and often multiple other family members of children with fragile X syndrome (FXS), will have a premutation, which may increase individual and family vulnerabilities. This article summarizes important gaps in knowledge and notes potential implications for pediatric providers with regard to developmental and medical risks for children and adolescents with an FMR1 premutation, including possible implications into adulthood.

METHODS

A structured electronic literature search was conducted on FMR1 pre- and full mutations, yielding a total of 306 articles examined. Of these, 116 focused primarily on the premutation and are included in this review.

RESULTS

Based on the literature review, 5 topic areas are discussed: genetics and epidemiology; phenotypic characteristics of individuals with the premutation; implications for carrier parents of children with FXS; implications for the extended family; and implications for pediatricians.

CONCLUSIONS

Although the premutation phenotype is typically less severe in clinical presentation than in FXS, premutation carriers are much more common and are therefore more likely to be seen in a typical pediatric practice. In addition, there is a wide range of medical, cognitive/developmental, and psychiatric associated features that individuals with a premutation are at increased risk for having, which underscores the importance of awareness on the part of pediatricians in identifying and monitoring premutation carriers and recognizing the impact this identification may have on family members.

Protecting Bone Health in Pediatric Rheumatic Diseases: Pharmacological Considerations

Bone health in children with rheumatic conditions may be compromised due to several factors related to the inflammatory disease state, delayed puberty, altered life style, including decreased physical activities, sun avoidance, suboptimal calcium and vitamin D intake, and medical treatments, mainly glucocorticoids and possibly some disease-modifying anti-rheumatic drugs. Low bone density or even fragility fractures could be asymptomatic; therefore, children with diseases of high inflammatory load, such as systemic onset juvenile idiopathic arthritis, juvenile dermatomyositis, systemic lupus erythematosus, and those requiring chronic glucocorticoids may benefit from routine screening of bone health. Most commonly used assessment tools are laboratory testing including serum 25-OH-vitamin D measurement and bone mineral density measurement by a variety of methods, dual-energy X-ray absorptiometry as the most widely used. Early disease control, use of steroid-sparing medications such as disease-modifying anti-rheumatic drugs and biologics, supplemental vitamin D and calcium, and promotion of weight-bearing physical activities can help optimize bone health. Additional treatment options for osteoporosis such as bisphosphonates are still controversial in children with chronic rheumatic diseases, especially those with decreased bone density without fragility fractures. This article reviews common risk factors leading to compromised bone health in children with chronic rheumatic diseases and discusses the general approach to prevention and treatment of bone fragility.

Birmingham epidermolysis severity score and vitamin D status are associated with low BMD in children with epidermolysis bullosa

Bone status impairment represents a complication of generalized forms of epidermolysis bullosa (EB); however, the prevalence and the main determinants of this event in localized forms remain poorly defined. Birmingham epidermolysis bullosa severity (BEBS) score and 25-hydroxyvitamin D levels are strongly associated with low bone mass, suggesting that vitamin D may play a potential beneficial role in bone health. Further longitudinal studies are needed in order to confirm this hypothesis.

INTRODUCTION

Bone status impairment represents a complication of generalized forms of EB; thus, we aimed to estimate the prevalence of low bone mass, to examine mineralization differences in various EB subtypes and to identify the most important determinants of bone impairment in children with either generalized or localized EB.

METHODS

An observational study of 20 children (11 males; mean age ± standard deviation, 11.7 ± 3.9 years) with EB was performed. Clinical history, physical examination, laboratory studies, X-ray of the left hand and wrist for bone age, and dual energy X-ray absorptiometry scans of the lumbar spine were obtained. Areal bone mineral density (aBMD Z-scores) and bone mineral apparent density were related to the BEBS score.

RESULTS

Areal BMD Z-score (mean -1.82 ± 2.33, range, -7.6-1.7) was reduced (<-2 SD) in 8 patients (40%), whereas aBMD Z-score adjusted for bone age was low in 7 patients (35%). BEBS score and 25-hydroxyvitamin D serum levels were the most important elements associated with aBMD (P = 0.0001 and P = 0.016, respectively). A significant correlation between the aBMD Z-score and area of skin damage, insulin-like growth factor-1, C-reactive protein, and sodium serum levels was also found.

CONCLUSIONS

Low aBMD can be considered a systemic complication of EB, primarily associated with BEBS score and 25-hydroxyvitamin D levels. Therefore, longitudinal evaluation of bone status is ongoing in these patients to define whether vitamin D supplementation would prevent, or at least reduce, bone status impairment.

Do metabolic syndrome and its components have an impact on bone mineral density in adolescents?

In recent years, there has been growing concern about the occurrence of metabolic syndrome (MetS) at an early age and its effects on bone mass in adolescents. Adolescence is considered a critical period for bone mass gain. Impaired bone acquisition during this phase can lead to “suboptimal” peak bone mass and increase the risk of osteopenia/osteoporosis and fractures in old age. The objective of this review was to perform a critical analysis of articles that specifically focus on this age group, evaluating the influence of MetS and its components on bone mineral density in adolescents. A possible relationship between this syndrome and bone mass has been demonstrated, but the number of studies addressing this topic in adolescents is small. Despite the scarcity of evidence, the results of those studies show that Metabolic Syndrome is negatively correlated with bone mass and also that some components of MetS are negatively correlated with bone mineral density in adolescents. However, the associations between MetS and bone mass development need to be further explored in the age group corresponding to adolescence. Further good-quality studies are necessary to complement the understanding of this relationship.

Dietary 2-oxoglutarate prevents bone loss caused by neonatal treatment with maximal dexamethasone dose

Synthetic glucocorticoids (GCs) are widely used in the variety of dosages for treatment of premature infants with chronic lung disease, respiratory distress syndrome, allergies, asthma, and other inflammatory and autoimmune conditions. Yet, adverse effects such as glucocorticoid-induced osteoporosis and growth retardation are recognized. Conversely, 2-oxoglutarate (2-Ox), a precursor of glutamine, glutamate, and collagen amino acids, exerts protective effects on bone development. Our aim was to elucidate the effect of dietary administered 2-Ox on bone loss caused by neonatal treatment with clinically relevant maximal therapeutic dexamethasone (Dex) dose. Long bones of neonatal female piglets receiving Dex, Dex+2-Ox, or untreated were examined through measurements of mechanical properties, density, mineralization, geometry, histomorphometry, and histology. Selected hormones, bone turnover, and growth markers were also analyzed. Neonatal administration of clinically relevant maximal dose of Dex alone led to over 30% decrease in bone mass and the ultimate strength ( P < 0.001 for all). The length (13 and 7% for femur and humerus, respectively) and other geometrical parameters (13-45%) decreased compared to the control ( P < 0.001 for all). Dex impaired bone growth and caused hormonal imbalance. Dietary 2-Ox prevented Dex influence and vast majority of assessed bone parameters were restored almost to the control level. Piglets receiving 2-Ox had heavier, denser, and stronger bones; higher levels of growth hormone and osteocalcin concentration; and preserved microarchitecture of trabecular bone compared to the Dex group. 2-Ox administered postnatally had a potential to maintain bone structure of animals simultaneously treated with maximal therapeutic doses of Dex, which, in our opinion, may open up a new opportunity in developing combined treatment for children treated with GCs. Impact statement The present study has showed, for the first time, that dietary 2-oxoglutarate (2-Ox) administered postnatally has a potential to improve/maintain bone structure of animals simultaneously treated with maximal therapeutic doses of dexamethasone (Dex). It may open the new direction in searching and developing combined treatment for children treated with glucocorticoids (GCs) since growing group of children is exposed to synthetic GCs and adverse effects such as glucocorticoid-induced osteoporosis and growth retardation are recognized. Currently proposed combined therapies have numerous side effects. Thus, this study proposed a new direction in combined therapies utilizing dietary supplementation with glutamine derivative. Impairment caused by Dex in presented long bones animal model was prevented by dietary supplementation with 2-Ox and vast majority of assessed bone parameters were restored almost to the control level. These results support previous thesis on the regulatory mechanism of nutrient utilization regulated by glutamine derivatives and enrich the nutritional science.

Controlled Pilot Study of High-Impact Low-Frequency Exercise on Bone Loss and Vital-Sign Stabilization in Adolescents With Eating Disorders

PURPOSE

Adolescents with anorexia nervosa (AN) face an increased lifetime risk of bone fragility. This randomized controlled study examined the efficacy and safety of a high-impact activity program on markers of bone turnover and stabilization of vital signs (VSS).

METHODS

Forty-one hospitalized adolescents with AN were randomly assigned to routine care or routine care plus 20 jumps twice daily. Bone markers were measured at baseline days 1-3 (T1), days 4-6 (T2), and days 7-9 (T3). The primary outcome was change in bone-specific alkaline phosphatase (BSAP) at T3 adjusted for BSAP and % median body mass index at T1. Secondary outcomes were serum N-telopeptide (NTX) and osteocalcin at T3. Safety was determined by comparing weight gain, time to VSS and length of stay for each group.

RESULTS

BSAP, NTX, or osteocalcin did not differ between groups at baseline or at T3. BSAP and NTX at T3 were not associated with group of enrollment or % median body mass index. VSS was significantly reduced in the intervention group compared with the control group (11.6 ± 5.7 days vs. 17 ± 10.5 days, p = .049). There was no significant difference in weight gain or length of stay between groups.

CONCLUSIONS

Twice-daily jumping activity failed to influence markers of bone turnover in adolescents with AN but was well tolerated, shortened time to vital-sign stabilization and did not slow weight gain.

FIVE-YEAR OUTCOMES AFTER LONG-TERM OXANDROLONE ADMINISTRATION IN SEVERELY BURNED CHILDREN: A RANDOMIZED CLINICAL TRIAL

Administration of oxandrolone, a nonaromatizable testosterone analog, to children for 12 months following severe burn injury has been shown to improve height, increase bone mineral content (BMC), reduce cardiac work, and augment muscle strength. Surprisingly, the increase in BMC persists well beyond the period of oxandrolone administration. This study was undertaken to determine if administration of oxandrolone for 2 years yields greater effects on long-term BMC and bone mineral density (BMD). Patients between 0 and 18 years of age with ≥30% of total body surface area burned were consented to an IRB-approved protocol and randomized to receive either placebo (n = 84) or 0.1 mg/kg oxandrolone orally twice daily for 24 months (n = 35). Patients were followed prospectively from the time of admission until 5 years postburn in a single-center, intent-to-treat setting. Height, weight, BMC, and BMD were recorded annually through 5 years postinjury. The long-term administration of oxandrolone for 16 ± 1 months postburn (range, 12.1-25.2 months) significantly increased whole-body (WB) BMC (p < 0.02) and lumbar spine (LS) BMC (p < 0.05); these effects were significantly pronounced for a longer time in patients who were in growth spurt years (7-18 years). When adjusted for height, sex, and age, LS BMD was found to significantly increase with long-term oxandrolone administration (p < 0.0009). Fewer patients receiving oxandrolone exhibited LS BMD z scores below -2.0 as compared with controls, indicating a significantly reduced risk for future fracture with oxandrolone administration. Long-term oxandrolone patients had significantly greater height velocity than controls throughout the first 2-year postburn (p < 0.05). No adverse side effects were attributed to the long-term administration of oxandrolone. A comparison of the current patients receiving long-term oxandrolone to previously described patients receiving 12 months of oxandrolone revealed that long-term oxandrolone administration imparted significantly greater increases in WB-BMC, WB-BMD, and LS-BMD (p < 0.05). In conclusion, the administration of oxandrolone for up to 24 months to severely burned pediatric patients significantly improves WB BMC, LS BMC, LS BMD, and height velocity. The administration of long-term oxandrolone was more efficacious than administration for 12 months. Additionally, fewer patients in the oxandrolone cohort met the diagnostic criteria for pediatric osteoporosis, pointing to a reduced risk for future bone fracture. This study demonstrates that administering oxandrolone for up to 2 years following severe burn injury results in greater improvements in BMC, BMD, and height velocity.