Cross-sectional reference data for phalangeal quantitative ultrasound from early childhood to young-adulthood according to gender, age, skeletal growth, and pubertal development

Effects of antiepileptic therapy on bone mineral status evaluated by phalangeal quantitative ultrasound in pediatric patients with epilepsy and motor impairment

BACKGROUND

In epileptic patients with motor disability, it's difficult to disentangle the effects of antiepileptic drugs (AEDs) on bone health from those provoked by impaired mobility. The aim of this study was to evaluate the effects of AEDs on bone mineral status by phalangeal quantitative ultrasound (QUS), a no-radiation and non-invasive method, in pediatric patients with motor impairment and epilepsy.

METHODS

We enrolled 56 patients (31 females, 25 males) with epilepsy and motor impairment and 24 children with only motor disability (13 females, 11 males). Patients were stratified by Gross Motor Function Classification System Scale (GMFCS) in 4 groups: group A1 with epilepsy and mild motor impairment (GMFCS levels I-II), group A2 with only mild motor impairment, group B1 with epilepsy and severe motor impairment (GMFCS levels III-V), group B2 with only severe motor impairment. The bone mineral status was evaluated by phalangeal QUS and amplitude-dependent speed of sound (AD-SoS) Z-score was calculated for each patient.

RESULTS

The four groups showed no significant differences in age, gender and 25-hydroxyvitamin D levels. The group B1 had a statistically lower amplitude-dependent speed of sound Z-score as compared to group A2 (P<0.05). The multivariate analysis of independent factors revealed a significant correlation between amplitude-dependent speed of sound Z-score and Gross Motor Function Classification System levels (P=0.004). The mean Z-score value decreased by 0.53, increasing the motor impairment.

CONCLUSIONS

The bone mineral status measured as AD-SoS strongly correlates with severity of motor disability evaluated by GMFCS as compared to antiepileptic therapy and 25-hydroxyvitamin D levels.

Technical note: Application and potentiality of quantitative ultrasonometry for the evaluation of bone mineral density status

The evaluation of bone mineral density (BMD) is an important task in paleopathology. Techniques commonly applied in bone quantity assessment, such as DXA or radiogrammetry (XR), suffer from several limitations when applied to skeletal remains. In recently published research, we developed a new methodology and new reference curves for the evaluation of BMD on human skeletal remains, applying for the first time Quantitative Ultrasonometry (QUS), a user-friendly, portable, and reliable clinical technique. This study aims to apply this new methodology to an archeological sample and to compare the results with those obtained through XR. We apply QUS and XR to a sample of 104 adults from Medieval Italian cemeteries. Fragility fractures were recorded. Descriptive statistics and comparisons between sexes, age-at-death cohorts, and individuals with and without fragility fractures were performed. Moreover, univariate and multivariate logistic regression models were used to define the parameters most predictive of fracture risk in past populations. The comparison between sexes showed no significant results concerning BMD parameters, whereas a decrease in BMD with increasing age is confirmed. The comparison between fracture and non-fracture individuals and the logit model demonstrated that QUS parameters, especially UBPI, are more reliable predictors of fracture risk in comparison to XR. Our results confirmed that QUS is a valuable technique that can be efficiently applied to archeological remains, also considering its portability. We also propose a modification of the previously published QUS standard curves, to easily assess osteopenia and osteoporosis in archeological material.

Identifying Calcaneal Anatomical Regions of Interest (ROI) for Quantitative Ultrasound Application in Subadults

Whilst quantitative ultrasound can be reliably used to assess bone health in adults, the fixed location of the transducers in current devices may result in inaccurate and unreliable measurements in bone assessment in children due to the variation in foot size during growth. To improve positioning for paediatric assessment, Jaworski et al. (1995) created an anatomical method to identify the region of interest (ROI), however, there have been no medical imaging studies to confirm that the Jaworski method results in consistent placement of the transducer on the centre of the calcaneal body to avoid edge artefacts. In this study, computed tomography scans of the tarsus were collected from 498 individuals (258 females; 240 males) aged 2 to 20 years and used to create three novel anatomical methods to identify ROI on the calcaneus using palpable landmarks. In addition, the established Jaworski method was applied to the same scans and compared to our novel methods. The maximum ROI significantly increased with age with males having significantly greater diameters, supporting the recommendation that ½ inch diameter transducers should be used on individuals younger than 7 years of age. We identified that 79% of the 'Jaworski points' lied anterosuperior to the ROI centre point identified in this study, with 10% of the points lying outside the ROI. Of the three novel methods, only the calcaneal insertion method demonstrated small measurement variance between individuals of the same age in each sex and is therefore the preferred method for ultrasound clinical application.

Osteoporosis in children and adolescents: when to suspect and how to diagnose it

Early recognition of osteoporosis in children and adolescents is important in order to establish an appropriate diagnosis of the underlying condition and to initiate treatment if necessary. In this review, we present the diagnostic work-up, and its pitfalls, of pediatric patients suspected of osteoporosis including a careful collection of the medical and personal history, a complete physical examination, biochemical data, molecular genetics, and imaging techniques. The most recent and relevant literature has been reviewed to offer a broad overview on the topic. Genetic and acquired pediatric bone disorders are relatively common and cause substantial morbidity. In recent years, there has been significant progress in the understanding of the genetic and molecular mechanistic basis of bone fragility and in the identification of acquired causes of osteoporosis in children. Specifically, drugs that can negatively impact bone health (e.g. steroids) and immobilization related to acute and chronic diseases (e.g. Duchenne muscular dystrophy) represent major risk factors for the development of secondary osteoporosis and therefore an indication to screen for bone mineral density and vertebral fractures. Long-term studies in children chronically treated with steroids have resulted in the development of systematic approaches to diagnose and manage pediatric osteoporosis.

CONCLUSIONS

Osteoporosis in children requires consultation with and/or referral to a pediatric bone specialist. This is particularly relevant since children possess the unique ability for spontaneous and medication-assisted recovery, including reshaping of vertebral fractures. As such, pediatricians have an opportunity to improve bone mass accrual and musculoskeletal health in osteoporotic children.

WHAT IS KNOWN

• Both genetic and acquired pediatric disorders can compromise bone health and predispose to fractures early in life. • The identification of children at risk of osteoporosis is essential to make a timely diagnosis and start the treatment, if necessary.

WHAT IS NEW

• Pediatricians have an opportunity to improve bone mass accrual and musculoskeletal health in osteoporotic children and children at risk of osteoporosis. • We offer an extensive but concise overview about the risk factors for osteoporosis and the diagnostic work-up (and its pitfalls) of pediatric patients suspected of osteoporosis.

Which Exercise for Low Back Pain? (WELBack) trial predicting response to exercise treatments for patients with low back pain: a validation randomised controlled trial protocol

INTRODUCTION

Exercise therapy is the most recommended treatment for chronic low back pain (LBP). Effect sizes for exercises are usually small to moderate and could be due to the heterogeneity of people presenting with LBP. Thus, if patients could be better matched to exercise based on individual factors, then the effects of treatment could be greater. A recently published study provided evidence of better outcomes when patients are matched to the appropriate exercise type. The study demonstrated that a 15-item questionnaire, the Lumbar Spine Instability Questionnaire (LSIQ), could identify patients who responded best to one of the two exercise approaches for LBP (motor control and graded activity). The primary aim of the current study isill be to evaluate whether preidentified baseline characteristics, including the LSIQ, can modify the response to two of the most common exercise therapies for non-specific LBP. Secondary aims include an economic evaluations with a cost-effectiveness analysis.

METHODS AND ANALYSIS

Participants (n=414) will be recruited by primary care professionals and randomised (1:1) to receive motor control exercises or graded activity. Participants will undergo 12 sessions of exercise therapy over an 8-week period. The primary outcome will be physical function at 2 months using the Oswestry Disability Index. Secondary outcomes will be pain intensity, function and quality of life measured at 2, 6 and 12 months. Potential effect modifiers will be the LSIQ, self-efficacy, coping strategies, kinesiophobia and measures of nociceptive pain and central sensitisation. We will construct linear mixed models with terms for participants (fixed), treatment group, predictor (potential effect modifier), treatment group×predictor (potential effect modifier), physiotherapists, treatment group×physiotherapists and baseline score for the dependent variable.

ETHICS AND DISSEMINATION

This study received ethics approval from the Hamilton Integrate Research Ethics Board. Results will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04283409.

Skeletal status assessed by quantitative ultrasound and dual-energy X-ray absorptiometry in children with inflammatory bowel disease: A 2-year prospective study

PURPOSE

To assess the bone status in children with inflammatory bowel diseases (IBD) using quantitative ultrasound (QUS) measurement and dual-energy X-ray absorptiometry (DXA) at baseline and after two years of adequate treatment of the IBD and bone protection medication.

METHODS

Sixteen children (six boys) with IBD, aged 13.4±2.4 years, were examined at baseline and two years later. DXA was used to asses bone mineral density (BMD) and reference data were provided by the device's manufacturer (Hologic Explorer). QUS measurements were performed in patients and controls - 48 healthy children.

RESULTS

Mean Z-scores for TB- and s-BMD were significantly below zero for both, baseline and follow-up (-2.61±0.99 and -2.48±0.88 for TB, and -1.83±1.33 and -1.61±1.19 for s-BMD, respectively), and did not differ significantly, as well as mean Ad-SoS Z-score. The changes in time of TB Z-score and body weight Z-score correlated positively (r=0.63; P<0.01). The QUS results did not differ between patients and controls. There was a negative correlation between the baseline nutritional status and the activity of the disease, as well as of the number of flares before the enrolment and Ad-SoS Z-score.

CONCLUSIONS

BMD was found to be lowered both at baseline and follow-up. No further deterioration was observed during 2-year follow-up. Proper treatment, defined as treatment following ECCO Guidelines, may allow to keep a similar trend in the development of bone tissue as in healthy children. The bone properties assessed by QUS method did not differ between patients and controls. QUS at hand phalanges appears not to be proper diagnostic tool in IBD children.

Shedding "LIGHT" on the Link between Bone and Fat in Obese Children and Adolescents

Obesity may affect bone health, but literature reports are contradictory about the correlation of body mass index (BMI) and bone markers. LIGHT, one of the immunostimulatory cytokines regulating the homeostasis of bone and adipose tissue, could be involved in obesity. The study involved 111 obese subjects (12.21 ± 3.71 years) and 45 controls. Patients underwent the evaluation of bone status by quantitative ultrasonography (QUS). LIGHT amounts were evaluated in sera by ELISA, whereas its expression on peripheral blood cells was evaluated by flow cytometry. Osteoclastogenesis was performed by culturing peripheral blood mononuclear cells (PBMCs) with or without anti-LIGHT antibodies. Obese patients showed significant high BMI-standard deviation score (SDS), weight-SDS, and Homeostatic model assessment for insulin resistance (HOMA-IR) that negatively correlated with the reduced Amplitude Dependent Speed of Sound (AD-SoS)-Z-score and Bone Transmission Time (BTT-Z)-score. They displayed significantly higher serum levels of LIGHT compared with controls (497.30 ± 363.45 pg/mL vs. 186.06 ± 101.41 pg/mL, p < 0.001). LIGHT expression on monocytes, CD3+-T-cells, and neutrophils was also higher in obese patients than in the controls. Finally, in PBMC cultures, the addition of anti-LIGHT antibodies induced a significant osteoclastogenesis inhibition. Our study highlighted the high serum levels of LIGHT in obese children and adolescents, and its relationship with both the grade of obesity and bone impairment.

Bone quality in fluoride-exposed populations: A novel application of the ultrasonic method

BACKGROUND

Various studies, mostly with animals, have provided evidence of adverse impacts of fluoride (F-) on bone density, collagen and microstructure, yet its effects on overall bone quality (strength) has not been clearly or extensively characterized in human populations.

OBJECTIVE

In this observational study, we assessed variation in an integrated measures of bone quality in a population exposed to wide-ranging F- levels (0.3 to 15.5 mg/L) in drinking water, using a novel application of non-ionizing ultrasonic method.

METHOD

We collected 871 speed of sound (SOS) measurements from 341 subjects residing in 25 communities, aged 10-70 years (188 males and 153 females). All subjects received scans of the cortical radius and tibia, and adults over the age of 19 received an additional scan of the phalanx. Associations between F- in drinking water and 24-h urine samples, and SOS as a measure of bone quality, were evaluated in bivariate and multivariable regressions adjusting for age, sex, BMI, smoking, and toothpaste use.

RESULTS

We found negative associations between F- exposure and bone quality at all three bones. Adult tibial SOS showed the strongest inverse association with F- exposure, which accounted for 20% of the variance in SOS measures (r = 0.45; n = 199; p < 0.0001). In adjusted analysis, a 1 mg/L increase in F- in drinking water was related to a reduction of 15.8 m/s (95% CI: -21.3 to -10.3), whereas a 1 mg/L increase in 24-h urinary F- (range: 0.04-39.5 mg/L) was linked to a reduction of 8.4 m/s (95% CI: -12.7, -4.12) of adult tibial SOS. Among adolescents, in contrast, weaker and non-significant inverse associations between F- exposure and SOS were found, while age, gender, and BMI were more significant predictors than in adults.

CONCLUSIONS

These results are indicative of a fluoride-induced deterioration of bone quality in humans, likely reflecting a combination of factors related to SOS: net bone loss, abnormal mineralization and collagen formation, or altered microarchitecture. The portable and low-cost ultrasound technique appears potentially useful for assessment of bone quality, and should be tested in other locations and for other bone-related disorders, to assess the feasibility of its more extensive diagnostic use in hard-to-reach rural regions.

Ultrasonic Backscatter Difference Measurement of Bone Health in Preterm and Term Newborns

Metabolic bone disease of prematurity remains a significant problem for preterm infants. Quantitative ultrasound (QUS) has potential as a non-invasive tool for assessing bone health of newborns. The aim of this study was to assess bone health in preterm and term newborns using ultrasonic backscatter difference measurement. This study analyzed a total of 493 neonates, including 239 full-term infants (gestational age [GA] >37 wk), 201 preterm I infants (GA: 32-37 wk) and 53 extreme preterm II infants (GA <32 wk). Ultrasonic backscatter measurements were performed on the calcaneus of infants at birth, and the normalized mean of the backscatter difference spectrum (nMBD) was calculated as an ultrasonic index of neonatal bone status. Simple and multiple linear regressions were performed to determine the association of ultrasonic nMBD with GA, anthropometric characteristics and biochemical markers. Statistically significant differences in GA, anthropometric characteristics (birth weight, birth length [BL], birth head circumference and body mass index [BMI]) and biochemical markers (alkaline phosphatase, serum calcium and serum phosphate) were observed among preterm and term infants. The nMBD for term infants (median = 3.72 dB/μs, interquartile range [IR] = 1.95 dB/μs) was significantly higher than that for preterm I infants (median = 1.95 dB/μs, IR = 3.12 dB/μs), which was, in turn, significantly higher than that for preterm II infants (median = 0.19 dB/μs, IR = 3.50 dB/μs). The nMBD yielded moderate correlations (ρ = 0.57-0.62, p < 0.001) with GA and anthropometric characteristics and weak correlations (|ρ| = 0.08-0.21, p < 0.001 or not significant) with biochemical markers. Multivariate regressions revealed that only BL (p = 0.002) and BMI (p = 0.032) yielded significantly independent contributions to the nMBD measurement, and combinations of BL and BMI could explain up to 42% of the variation of nMBD in newborn infants. This study found that ultrasonic backscatter difference measurement might be helpful in bone health evaluation in preterm and term newborns. The utility of ultrasonic backscatter measurement in diagnosis of metabolic bone disease in infants should be investigated further.

Methyl-CpG-binding protein 2 (MECP2) mutation type is associated with bone disease severity in Rett syndrome

Background

More than 95% of individuals with RTT have mutations in methyl-CpG-binding protein 2 (MECP2), whose protein product modulates gene transcription. The disorder is caused by mutations in a single gene and the disease severity in affected individuals can be quite variable. Specific MECP2 mutations may lead phenotypic variability and different degrees of disease severity. It is known that low bone mass is a frequent and early complication of subjects with Rett syndrome. As a consequence of the low bone mass Rett girls are at an increased risk of fragility fractures. This study aimed to investigate if specific MECP2 mutations may affects the degree of involvement of the bone status in Rett subjects.

Methods

In 232 women with Rett syndrome (mean age 13.8 ± 8.3 yrs) we measured bone mineral density at whole body and at femur (BMD-FN and BMD-TH) by using a DXA machine (Hologic QDR 4500). QUS parameters were assessed at phalanxes by Bone Profiler-IGEA (amplitude dependent speed of sound: AD-SoS and bone transmission time: BTT). Moreover, ambulation capacity (independent or assisted), fracture history and presence of scoliosis were assessed. We divided the subjects with the most common point mutations in two group based on genotype-phenotype severity; in particular, there has been consensus in recognising that the mutations R106T, R168X, R255X, R270X are considered more severe.

Results

As aspect, BMD-WB, BMD-FN and BMD-TH were lower in subjects with Rett syndrome that present the most severe mutations with respect to subjects with Rett syndrome with less severe mutations, but the difference was statistically significant only for BMD-FN and BMD-TH (p < 0.05). Also both AD-SoS and BTT values were lower in subjects that present the most severe mutations with respect to less severe mutations but the difference was not statistically significant. Moreover, subjects with Rett syndrome with more severe mutations present a higher prevalence of scoliosis (p < 0.05) and of inability to walk (p < 0.05).

Conclusion

This study confirms that MECP2 mutation type is a strong predictor of disease severity in subjects with Rett syndrome. In particular, the subjects with more severe mutation present a greater deterioration of bone status, and a higher prevalence of scoliosis and inability to walk.

Irisin and Bone: From Preclinical Studies to the Evaluation of Its Circulating Levels in Different Populations of Human Subjects

Almost four years after the discovery of the anabolic action of irisin on bone in mice, ample clinical evidence is emerging in support of its additional physiological relevance in human bone. Irisin inversely correlates with sclerostin levels in adults with prediabetes and with vertebral fragility fractures in post-menopausal women. Furthermore, in athletes we observed a positive correlation between irisin and bone mineral density at different anatomical sites. Our group also described a positive association between serum irisin and bone status in healthy children and multivariate regression analysis showed that irisin is a stronger determinant of bone mineral status than bone alkaline phosphatase. In children with type 1 diabetes mellitus, serum irisin concentrations are positively associated with bone quality and with glycemic control following continuous subcutaneous insulin infusion. Additionally, our in vitro studies suggest the existence of a negative interplay between PTH and irisin biology and these results were also supported by the observation that post-menopausal women with primary hyperparathyroidism have lower levels of irisin compared to matched controls. In this review, we will focus on recent findings about circulating level of irisin in different populations of human subjects and its correlation with their bone status.

Bone status in relation to ambulatory performance in girls with Rett syndrome: a 10-year longitudinal study

BACKGROUND

Low bone mass is a frequent and early complication of girls with Rett syndrome. As a consequence of the low bone mass, Rett patients are at an increased risk of fragility fractures. This study aimed to investigate the long-term influences of mobility on bone status in girls with Rett syndrome.

METHODS

In 58 girls with Rett syndrome, biochemical parameters and quantitative ultrasound parameters at phalanges (amplitude-dependent speed of sound: AD-SoS and bone transmission time: BTT) were measured at baseline and after 5 and 10 years. The subjects were divided into two groups: nonambulatory (n = 28) and ambulatory (n = 30).

RESULTS

In nonambulatory Rett subjects, the values of AD-SoS and BTT were significantly lower than in ambulatory Rett subjects at each time point. However, during the 10-year follow-up both ambulatory and nonambulatory Rett patients showed a similar worsening in their bone status.

CONCLUSION

This longitudinal study suggests that both ambulatory and nonambulatory Rett subjects present a progressive deterioration of bone status as assessed by quantitative ultrasound parameters, and the ambulatory impairment and the nutritional status seem to play a key role in the deterioration of bone status.

Quantitative Ultrasound of Proximal Phalanxes in Childhood Acute Lymphoblastic Leukemia Survivors

Reduced bone mineral density (BMD) is a well-known complication in childhood acute lymphoblastic leukemia (ALL) survivors; the optimal method to assess BMD is still debated. We studied BMD by quantitative ultrasound (QUS) in 72 ALL survivors, and evaluated any correlation with cumulative doses of steroids and cytotoxic agents. Mean age at diagnosis was 61±45 months, while mean age at QUS was 318.3±129.6 months; mean period of follow-up was 41.2±37.8 months. Mean amplitude-dependent speed of sound z-score was -1.22±1.19. Ten survivors (13.8%) presented a z-score below -2 SD. A negative correlation was found between amplitude-dependent speed of sound z-score and age at diagnosis (P=0.01). A positive correlation was observed with length of follow-up (P=0.01). No correlation was found with cytotoxic drugs. This study represents the largest cohort of childhood ALL survivors studied by QUS. Our results suggest that QUS for its characteristics of being radiation free may be an effective option to assess BMD in pediatric age. In addition, our data outline the importance to improve the awareness about the specific expression of this complication in the pediatric age, concerning the major determinants of bone impairment, which are the disease itself and the phase of bone growth when the disease occurs.

Irisin serum levels are positively correlated with bone mineral status in a population of healthy children

BACKGROUND

Irisin is a myokine secreted by skeletal muscle during physical activity. Irisin treatment increased cortical bone mineral density (BMD) in young healthy mice and restored bone and muscle mass loss in a mouse model of disuse-induced osteoporosis and muscular atrophy. In humans, Irisin was positively correlated with BMD in young athletes. Considering that the bone mass reached during childhood is one of the most important determinants of lifelong skeletal health, we sought to determine if Irisin levels were correlated with bone mineral status in children.

METHODS

Irisin and bone metabolic markers were quantified in sera and bone mineral status was evaluated by quantitative ultrasound in a population of 34 healthy children (9.82 ± 3.2 years).

RESULTS

We found that Irisin levels were positively correlated with the amplitude-dependent speed of sound Z-score (r = 0.305; p < 0.001), bone transmission time Z-score (r = 0.375; p < 0.001) and osteocalcin (r = 0.370; p < 0.001), and negatively with Dickkopf WNT Signaling Pathway Inhibitor 1 (r = -0.274; p < 0.001).

CONCLUSION

In a regression analysis model, Irisin was one of the determinants of bone mineral status to a greater extent than bone alkaline phosphatase and parathyroid hormone, indicating that Irisin might be considered as one of the bone formation markers during childhood.

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.

High irisin levels are associated with better glycemic control and bone health in children with Type 1 diabetes

AIM

Irisin is a new peptide produced mainly by the skeletal muscle playing an important role both in glucose/energy homeostasis and bone metabolism. Childhood type 1 diabetes mellitus (T1DM) is associated with decreased bone mass. We aimed to evaluate irisin levels in TD1M children and their correlation with bone metabolism and glycaemic control.

METHODS

Ninety-six T1DM subjects (12.2 ± 4 years), 56 on multiple daily injections (MDI), 40 on continuous subcutaneous insulin infusion (CSII), and 34 controls were included in the study. Irisin and bone remodeling markers were quantified in sera from patients and controls. Bone mineral density (BMD) was evaluated by QUS.

RESULTS

Increased irisin levels were found in T1DM patients respect to controls (p < 0.001). With adjustment for age, irisin levels significantly correlated negatively with HbA1c% (r = -0.105, p < 0.001), years of diabetes (r = -0.07, p < 0.04), 25(OH)-Vitamin D (r = -0.175, p < 0.0001), and positively with BTT-Z-score (r = 0.088, p = 0.016), and osteocalcin (r = 0.059, p < 0.04). We detected the highest levels of irisin in CSII patients compared to MDI and controls (p < 0.001 and p < 0.007 respectively).

CONCLUSIONS

We demonstrated high irisin levels in T1DM children and the association of highest irisin amounts to a better glycaemic control and bone health in TDM1 subjects on CSII.

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.

Evaluation of bone mineralization in former preterm born children: Phalangeal quantitative ultrasound cannot replace dual-energy X-ray absorptiometry

Background

Preterm infants are at risk of impaired bone health in later life. Dual-energy X-ray absorptiometry-scan (DXA) is the gold standard to determine bone mineralization. Phalangeal quantitative ultrasound (pQUS) is an alternative technique that is inexpensive, easy to use and radiation-free. The aim of this study was to investigate whether both techniques reveal equivalent results.

Materials and methods

Sixty former preterm infants (31 boys; 29 girls) received a DXA and pQUS at age 9 to 10 years. DXA measured bone mineral content (BMC) and bone mineral density (BMD) for total body and lumbar spine (L1-4), while pQUS measured the amplitude dependent speed of sound (AD-SoS) and bone transit time (BTT) at metacarpals II-IV providing continuous values and Z-scores based on age and sex. Four statistical methods evaluated the association between both techniques: Pearson's correlation coefficients, partial correlation coefficients adjusted for gestational age, height and BMI, Bland-Altman analysis and cross tabulation.

Results

Both techniques showed a statistically significant weak correlation for continuous values as well as Z-scores (0.291–0.462, p < 0.05). Boys had significant and relatively high correlations (0.468–0.585, p < 0.05). In comparison, the correlations for girls were not significant. Correlation coefficients further decreased while calculating the partial correlations. The Bland-Altman plots showed poor agreement. Sensitivity ranged from 33% to 92% and specificity from 16% to 68%. Positive and negative predictive values ranged from 4% to 38% and 82% to 97%, respectively.

Conclusions

We found statistically significant weak correlations and poor agreement between DXA and pQUS measurements. DXA is not equivalent to pQUS and therefore not replaceable by this technique in former preterm born children at the age of 9 to 10 years.

•

DXA is the golden standard to determine bone mineralization, while Quantitative ultrasound is a radiation-free alternative.

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Four statistical tests were used to investigate the equivalence of both methods.

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Comparison of results of 60 preterm born children at age 9 to 10 years found poor agreement between both methods.

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There was a discrepancy in differentiating the same children with normal or reduced bone mineralization.

•

Quantitative ultrasound cannot replace the DXA scan for determination of bone mineralization in preterm born children.

Imaging of metabolic bone disease

Osteoporosis is the most important metabolic bone disease, with a wide distribution among the elderly. It is characterized by low bone mass and micro architectural deterioration of bone tissue, leading to enhanced bone fragility and a consequent increase in fracture risk. Identify bone weakening with an appropriate and accurate use of diagnostic imaging is of critical importance in the diagnosis and follow-up of osteoporotic patients. The aim of this review is to evaluate the detection rates of the different imaging modalities in the evaluation of bone strength, in the assessment of fracture risk and in the management of fragility fractures. (www.actabiomedica.it)

Effects of Short-Term Calcium Supplementation in Children and Adolescents with Phenylketonuria

Reduction of bone mineral density and the risk of osteopenia have been reported to occur in phenylketonuria (PKU) patients. This study aimed to evaluate the short-term effects of calcium supplementation in phenylketonuric children and adolescents. The study included 18 patients with PKU aged 5-18 yr (61% male) under clinical and nutritional treatment. Evaluation of food intake, anthropometry, and biochemical and phalangeal quantitative ultrasound were performed before (phase 1) and after (phase 2) calcium supplementation (1000 mg/d) for 34 d. Statistical analysis was performed using t test for paired samples, Wilcoxon's test, and McNemar's test (p <0.05). There was an inadequate intake of phosphorus and vitamin D, the same occurring with serum concentrations of these nutrients. About 50% of the patients had an accumulation of adipose tissue measures, with a negative correlation between Z-score, body mass index, and phalangeal quantitative ultrasound (amplitude-dependent speed of sound [AD-SoS]). There was a significant difference in urinary phosphorus excretion with higher values before supplementation. Comparison of the two phases revealed significantly higher AD-SoS values after the supplementation (p = 0.017). The reduction in phosphorus excretion associated with increased AD-SoS between the two phases suggested increased bone formation, and showed no negative effects in relation to short-term calcium supplementation in children and in adolescents with PKU.

Quantitative Ultrasonography Measurements of the Phalanges in Adolescents: A Mixed Longitudinal Study

This study examined the effect of pubertal development on Amplitude Dependent Speed of Sound (AD-SoS), accounting for the growth in stature among adolescents. A mixed-longitudinal design with 3 assessments across a 15-mo period in 439 adolescents (girls: 215; boys: 224) aged 9-16 y was used. Bayesian multilevel models were used to describe gender-specific AD-SoS variations among participants during pubertal years. Substantial increments in AD-SoS during pubertal years were observed in both genders. AD-SoS changes were positively related to stature, and the rate of stature growth per year. Quantitative ultrasonography was sensible to describe age-related changes of bone mass during pubertal development. It seemed clinically reliable to use AD-SoS in the study of bone growth and development.

Reference data for ultrasound bone characteristics in Hungarian children aged 7-19 years

Backround: Osteoporosis is a common disease and physical activity (PA) has a favourable influence on bone status.

AIM

To establish normative data for calcaneal quantitative ultrasound (QUS) bone characteristics in children and to analyse the relationships between PA, anthropometric and bone parameters.

SUBJECTS AND METHODS

Hungarian children aged 7-19 (n = 2674; 1325 girls, 1349 boys) provided PA, anthropometric and bone data. QUS parameters were registered with Sonost3000 densitometer (speed of sound: SOS, m/s; broadband ultrasound attenuation: BUA, dB/MHz; bone quantity index (BQI = αSOS + βBUA). Reference centiles of QUS parameters were constructed by LMS method. Multivariate linear regression models were used to analyse the relationships.

RESULTS

QUS bone parameters increased with age. There were no gender differences, except in 11- and 19-year-old children, where boys showed higher values. SOS (1497.15 ± 15.72 vs 1494.05 ± 14.81 m/s) and BQI (65.31 ± 16.71 vs 62.26 ± 15.78) were higher in athletic children. The regression model revealed significant relations between SOS and age, relative muscle mass and PA; BUA correlated with gender, morphological age, BMI, relative muscle mass and PA.

CONCLUSIONS

Changes in the bone parameters among 7-19-year-old Hungarian children depended on age, anthropometric dimensions and the level of PA. The normative data could be used for monitoring QUS bone parameters in children, leading to more effective interventions for healthy bones.

Constitutional bone impairment in Noonan syndrome

Noonan syndrome (NS) is an autosomal dominant trait characterized by genotypic and phenotypic variability. It belongs to the Ras/MAPK pathway disorders collectively named Rasopathies or neurocardiofaciocutaneous syndromes. Phenotype is characterized by short stature, congenital heart defects, facial dysmorphisms, skeletal and ectodermal anomalies, cryptorchidism, mild to moderate developmental delay/learning disability, and tumor predisposition. Short stature and skeletal dysmorphisms are almost constant and several studies hypothesized a role for the RAS pathway in regulating bone metabolism. In this study, we investigated the bone quality assessed by phalangeal quantitative ultrasound (QUS) and the metabolic bone profiling in a group of patients with NS, to determine whether low bone mineralization is primary or secondary to NS characteristics. Thirty-five patients were enrolled, including 20 males (55.6%) and 15 females (44.5%) aged 1.0-17.8 years (mean 6.4 ± 4.5, median 4.9 years). Each patients was submitted to clinical examination, estimation of the bone age, laboratory assays, and QUS assessment. Twenty-five percent of the cohort shows reduced QUS values for their age based on bone transmission time. Bone measurement were adjusted for multiple factors frequently observed in NS patients, such as growth retardation, delayed bone age, retarded puberty, and reduced body mass index, potentially affecting bone quality or its appraisal. In spite of the correction attempts, QUS measurement indicates that bone impairment persists in nearly 15% of the cohort studied. Our results indicate that bone impairment in NS is likely primary and not secondary to any of the phenotypic traits of NS, nor consistent with metabolic disturbances. © 2017 Wiley Periodicals, Inc.

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.

Imaging methods for bone mass evaluation during childhood and adolescence: an update

The objective of the work was to prepare an update on imaging methods for bone evaluation during childhood and adolescence. The text was based on original and review articles on imaging methods for clinical evaluation of bone mass in children and adolescents up to 20 years old. They were selected from BIREME and PUBMED by means of the following keywords: bone density; osteoporosis/diagnosis; densitometry; tomography; ultrasonography; magnetic resonance imaging; and radiogrammetry and published in Portuguese or English, in the last 10 years (2006-2016). The article was organized into topics with the description of peculiarities, advantages and disadvantages of each imaging method and their possible clinical applicability. Despite the emergence of new technologies, dual energy X-ray absorptiometry (DXA) remains the gold standard method for low bone mass diagnosis in all age groups. However, interpretation is complex in children and adolescents and demands skilled people. Quantitative computed tomography (QCT) [central QCT, peripheral QCT (pQCT) and high resolution-pQCT (HR-pQCT)] and magnetic resonance imaging (MRI) evaluate real bone density, but are not yet available for routine use. Quantitative bone ultrasound (QUS) shows good perspectives for its use in primary prevention actions. Automated radiogrammetry shows promise as a method able to flag individuals who might benefit from a complete bone assessment, but the clinical value of the measures still needs to be established.

Metabolic Outcomes, Bone Health, and Risk of Polycystic Ovary Syndrome in Girls with Idiopathic Central Precocious Puberty Treated with Gonadotropin-Releasing Hormone Analogues

BACKGROUND/AIMS

Gonadotropin-releasing hormone analogues (GnRHa) represent the gold standard treatment for central precocious puberty (CPP). We aimed to assess the effects of GnRHa treatment on metabolic outcomes, bone status, and polycystic ovary syndrome (PCOS) prevalence in young girls with idiopathic CPP (ICPP).

METHODS

We enrolled 94 ICPP girls who were at least 2 years after menarche and had already attained adult height at the time of the study: 56 previously treated with depot triptorelin (3.4 ± 0.6 years) and 38 untreated. Auxological parameters, lipid profile, homeostatic model assessment of insulin resistance (HOMA-IR), bone state, and prevalence of PCOS were assessed.

RESULTS

The 2 groups were similar for body mass index (BMI) and waist circumference. HOMA-IR, dehydroepi-androsterone sulfate, and Δ4-androstenedione were higher in the treated than in the untreated subjects (p < 0.001). Significant differences were found for amplitude-dependent speed of sound (p < 0.03) and bone transmission time z-scores (p < 0.01). The prevalence of PCOS was higher in the treated than in the untreated subjects (p < 0.04).

CONCLUSION

GnRHa therapy is associated with hyperandrogenism and an increase in insulin resistance and PCOS prevalence, but not with increased BMI or lipid profile alterations. Long-term evaluations at the time of expected peak bone mass achievement are needed to understand the persistent or transient nature of subtle bone abnormalities.

High Sclerostin and Dickkopf-1 (DKK-1) Serum Levels in Children and Adolescents With Type 1 Diabetes Mellitus

CONTEXT

Childhood type 1 diabetes mellitus (T1DM) is associated with decreased bone mass. Sclerostin and dickkopf-1 (DKK-1) are Wnt inhibitors that regulate bone formation.

OBJECTIVE

To evaluate sclerostin and DKK-1 levels in T1DM children and to analyze the influence of glycemic control on bone health.

DESIGN AND SETTING

Cross-sectional study conducted at a clinical research center.

PARTICIPANTS

One hundred and six T1DM subjects (12.2 ± 4 years), 66 on multiple daily injections (MDIs) and 40 on continuous subcutaneous infusion of insulin (CSII), and 80 controls.

RESULTS

The average bone transmission time (BTT) and amplitude-dependent speed of sound (AD-SoS) z scores were lower in patients with diabetes than in controls. Significantly increased DKK-1 (3593 ± 1172 vs 2652 ± 689 pg/mL; P < 0.006) and sclerostin (29.45 ± 12.32 vs 22.53 ± 8.29; P < 0.001) levels were found in patients with diabetes with respect to controls, particularly in patients on MDI compared with ones on CSII. Glycemic control was improved in CSII patients compared with MDI ones (P < 0.001) and was also associated with significantly higher BMI-SDS (P < 0.002) and BTT z scores (P < 0.02). With adjustment for age, multiple linear regression analysis of DKK-1 and sclerostin as dependent variables showed that levels of glycated hemoglobin, glucose, 25(OH) vitamin D, osteocalcin, and parathyroid hormone; years of diabetes; and BMI-SDS and AD-SoS z score were the most important predictors (P < 0.0001).

CONCLUSIONS

Our study highlighted (1) the high serum levels of DKK-1 and sclerostin in T1DM children and their relationship with altered glycemic control and (2) the effect of CSII on improvement of glycemic control and bone health in T1DM children.

Falls, fractures and bone density in Parkinson's disease - a cross-sectional study

AIM

Evidence suggests that falls and associated bone fractures are more frequent in patients suffering from Parkinson's disease (PD) than in the general population. In this cross-sectional study we evaluated the clinical and biochemical characteristics that are associated to falls, fractures and bone health in a population of PD subjects.

MATERIALS AND METHODS

Forty-two consecutive subjects suffering from idiopathic PD (mild-to-moderate severity) with/without falls in the previous year were included. They were characterized as regards functional independence, balance, fear of falling, bone density (ultrasound densitometry) and plasma levels of vitamin D. Twenty-one age- and sex-matched healthy subjects were evaluated as controls.

RESULTS

We detected a greater degree of osteoporosis in PD subjects as compared to controls, more pronounced in males than in females (Z-score: M -3.8 ± 1.6, F -2.28 ± 0.92, p = 0.0006). A positive correlation was found between independence levels and bone density or vitamin D levels. Twenty seven patients (64%) reported falls in the previous year. These were associated to post-traumatic fractures in 16 subjects (59% of fallers). Women fell more than men (fallers: 20 F/7 M; non fallers: 4 F/11 M, χ² test p = 0.02), although the occurrence of post-traumatic fractures among fallers did not differ between sexes (F 11/9, M 5/2, χ² test p > 0.05). Fallers with post-traumatic fractures showed higher degrees of motor impairment.

CONCLUSIONS

These findings confirm that falls and osteoporosis represent major health issues in PD, already in the middle stages of disease.

Brazilian pediatric reference data for quantitative ultrasound of phalanges according to gender, age, height and weight

Aims

To establish normative data for phalangeal quantitative ultrasound (QUS) measures in Brazilian students.

Methods

The sample was composed of 6870 students (3688 females and 3182 males), aged 6 to 17 years. The bone status parameter, Amplitude Dependent Speed of Sound (AD-SoS) was assessed by QUS of the phalanges using DBM Sonic BP (IGEA, Carpi, Italy) equipment. Skin color was obtained by self-evaluation. The LMS method was used to derive smoothed percentiles reference charts for AD-SoS according to sex, age, height and weight and to generate the L, M, and S parameters.

Results

Girls showed higher AD-SoS values than boys in the age groups 7–16 (p<0.001). There were no differences on AD-SoS Z-scores according to skin color. In both sexes, the obese group showed lower values of AD-SoS Z-scores compared with subjects classified as thin or normal weight. Age (r² = 0.48) and height (r² = 0.35) were independent predictors of AD-SoS in females and males, respectively.

Conclusion

AD-SoS values in Brazilian children and adolescents were influenced by sex, age and weight status, but not by skin color. Our normative data could be used for monitoring AD-SoS in children or adolescents aged 6–17 years.

Prematurity and low birth weight lead to altered bone geometry, strength, and quality in children

PURPOSE

Prematurity and low birth weight are associated with a decrease in bone mass. Aim of the study was to investigate bone geometry, strength, and quality in children born at term small for gestational age (term SGA), premature appropriate for gestational age (prem AGA), and premature SGA (prem SGA).

METHODS

91 patients (46 f, 45 m), mean age 11.28 years, height SDS 0.03 ± 0.21, and BMI SDS -0.31 ± 0.19. 20 were term SGA, 22 prem SGA, and 49 prem AGA. Bone geometry was assessed on the 2nd metacarpal bone, by evaluating the outer and inner diameter, the cortical area, medullary area, metacarpal index, cross-sectional area, and bone strength. Bone quality was evaluated by ultrasound and expressed as amplitude-dependent speed of sound and bone transmission time (BTT).

RESULTS

Term SGA, prem SGA, and prem AGA had values of bone geometry, strength, and quality significantly lower than our reference range (p < 0.05). Findings in the three groups were similar, apart from BTT, which was significantly reduced in prem SGA (p < 0.05). Fat percentage was the main determinant of BTT.

CONCLUSIONS

Children born either prematurely or SGA seem to have smaller and weaker bones. Those born both premature and SGA were the most affected.

Evaluation of impact of steroid replacement treatment on bone health in children with 21-hydroxylase deficiency

There are conflicting data regarding the potential impact of chronic glucocorticoid (GC) therapy on the bone mineral density of patients with congenital adrenal hyperplasia (CAH). Previous studies performed by dual-energy X-ray absorptiometry reported conflicting results. The purpose of this study was to assess the impact of chronic GC replacement treatment in children with classical and non classical CAH due to 21-hydroxylase deficiency (21-OHD) by quantitative ultrasonometry (QUS), an easy, cheap, and radiation-free technique. The study population consisted of nineteen 21-OHD patients (nine males) on lifelong GC treatment. Anthropometric, hormonal, and treatment data were recorded for each patient, and bone quality was assessed by QUS measurements. QUS findings (amplitude-dependent speed of sound and bone transmission time) were normal in 21-OHD patients and did not correlate with duration of treatment, daily, total, and yearly hydrocortisone dose. Furthermore, no significant correlation was found between QUS findings and 17α-hydroxy progesterone, Δ4-androstenedione, and testosterone levels. In conclusion, our results provide reassurance that currently used replacement doses of GC do not have a major impact on bone in patients with CAH. QUS seems to be a reliable tool for screening of bone health in children with 21-OHD.

Bone speed of sound throughout lifetime assessed with quantitative ultrasound in a Mexican population

The purpose of this study was to assess the bone speed of sound (SoS) through lifetime of a large Mexican population sample by determining the SoS from the radius and tibia using quantitative ultrasound (QUS). This is a cross-sectional evaluation of participants in the Mexican Health Workers Cohort Study. QUS measurements were performed using Sunlight Omnisense 8000P; Z- and T-scores were calculated for both sexes at the distal third of the radius and midshaft tibia, both on the nondominant side. A locally weighted regression smoothing scatterplot model was used to identify different phases of bone accretion and loss. A total of 9128 participants aged 1-75 yr were measured with QUS. Bone SoS accretion began 5 yr earlier in girls than boys (p<0.05). Maximal SoS or peak bone SoS was noted at 28 yr in the radius and at 22 yr in the tibia. Postmenopausal women (45-50 yr) showed significant SOS decrease at both sites (p<0.05) compared with men. Using the locally weighted regression smoothing scatterplot model, we found 5 different phases that constitute the biological development of bone over the life course, from ages 1-6, 7-12, 12-25, 25-50, and 50-75 yr (p<0.05). Our study shows the age- and sex-dependent changes and different phases of bone development expressed by SoS measurements of the radius and tibia. The values reported in this study can be used as a reference for urban Mexican population.

Lean mass as a total mediator of the influence of muscular fitness on bone health in schoolchildren: a mediation analysis

This report aims to analyse the independent association of lean mass and muscle fitness with bone mineral content (BMC) and bone mineral density (BMD), and to examine whether the relationship between muscle fitness and bone health is mediated by lean mass. Body composition (by dual energy X-ray absorptiometry (DXA)), muscle fitness, physical activity, age and height were measured in 132 schoolchildren (62 boys, aged 8-11 years). Analysis of covariance tested differences in bone-related variables by lean mass and muscle fitness, controlling for different sets of confounders. Linear regression models fitted for mediation analyses examined whether the association between muscle fitness and bone mass was mediated by lean mass. Children with good performance in handgrip and standing long jump had better and worse bone health, respectively. These differences disappeared after controlling for lean mass. Children with high lean mass had higher values in all bone-related variables. In addition, the relationship between muscle fitness and bone mass was fully mediated by lean mass. In conclusion, the relationship between upper-limbs muscle fitness and bone health seems to be dependent on lean mass but not on muscle fitness. Schoolchildren with high lean mass have more BMC and BMD in all regions. Lean mass mediates the association between muscle fitness and bone mass.

Reference equations for ultrasound bone densitometry of the radius in Central European children and adolescents

Bone density measurements are important for evaluation and follow-up of children with alterations in their mineral status (increased risk for fractures and osteoporosis subsequently). Interpretation of these measurements relies on the availability of appropriate reference equations. We developed gender-specific, age-dependent reference values of bone density for Central European children.

INTRODUCTION

In recent years, there has been an increasing demand for the measurement of bone density in children exposed to an increased risk of early alterations in their bone status. These values must be compared to an adequate reference population. The aim of the present study was to create reference equations of radial speed of sound (SOS) for Central European children and adolescents.

METHODS

In this cross-sectional study, SOS values were measured at the distal third of the radius in 581 Swiss children and adolescents (321 girls and 260 boys) aged 6 to 16 years using the Sunlight Omnisense® 7000P quantitative ultrasound system.

RESULTS

Gender-specific reference equations for SOS values were derived by polynomial regression and combined a cubic dependence of age and a linear dependence of height. The fitted SOS curves in our study population show a plateau period in both genders for younger ages followed by an increase phase beginning at the age of 12 in girls and 14 in boys. Neither the reported level of physical activity nor additional sport nor self-reported calcium intake influenced the reference equations.

CONCLUSIONS

Our results show a good agreement with similar studies using the same measurement technique on other body parts, suggesting a wide applicability of the obtained reference curves over different European populations.

Bone health in children and adolescents with steroid-sensitive nephrotic syndrome assessed by DXA and QUS

BACKGROUND

The management of steroid-sensitive nephrotic syndrome (SSNS) requires treatment with high-dose glucocorticoids (GCs), but GC usage causes the most frequent form of drug-induced osteoporosis. The aim of our study was to evaluate the impact of GCs on bone mineralization in patients with SSNS using two diagnostic tools, dual-energy X-ray densitometry (DXA) and quantitative ultrasound (QUS), and to compare the diagnostic efficacy of these two imaging tools.

METHODS

A total of 30 children with SSNS (age 5.20 ± 2.20 years) were evaluated at the start (T0) and after 1 (T1), 2.44 ± 0.75 (T2, 18 patients) and 5.96 ± 2.33 years (T4, 12 patients) of GC treatment. Patients who stopped at T2 were also evaluated at the 1-year timepoint after ceasing GC treatment (T3).

RESULTS

Of the patients assessed at T2, 11 had bone mineralization at the lower limit of normal versus those at T0 and T1, with bone mineralization rescue at the 1-year timepoint after GC discontinuation. At T4, 6/12 patients had densitometric parameters at the lower limit of normal values, and 3/12 patients showed reduced bone mineralization. The parameters derived from measurements of DXA and QUS were significantly related to each timepoint.

CONCLUSIONS

Patients with SSNS receiving GC therapy undergo bone status alteration related to the dosage and duration of the therapy. In terms of diagnostic efficacy, DXA and QUS were comparable, indicating that QUS is a reliable tool to evaluate bone health in children with SSNS.

[Factors that influence bone mass of healthy children and adolescents measured by quantitative ultrasound at the hand phalanges: a systematic review]

Objective:

To analyze the main factors that influence bone mass in children and teenagers assessed by quantitative ultrasound (QUS) of the phalanges.

Data source:

A systematic literature review was performed according to the PRISMA method with searches in databases Pubmed/Medline, SciELO and Bireme for the period 2001-2012, in English and Portuguese languages, using the keywords: children, teenagers, adolescent, ultrasound finger phalanges, quantitative ultrasound of phalanges, phalangeal quantitative ultrasound.

Data synthesis:

21 articles were included. Girls had, in QUS, Amplitude Dependent Speed of Sound (AD-SoS) values higher than boys during pubertal development. The values of the parameters of QUS of the phalanges and dual-energy X-ray Absorptiometry (DXA) increased with the increase of the maturational stage. Anthropometric variables such as age, weight, height, body mass index (BMI), lean mass showed positive correlations with the values of QUS of the phalanges. Physical activity has also been shown to be positively associated with increased bone mass. Factors such as ethnicity, genetics, caloric intake and socioeconomic profile have not yet shown a conclusive relationship and need a larger number of studies.

Conclusions:

QUS of the phalanges is a method used to evaluate the progressive acquisition of bone mass during growth and maturation of individuals in school phase, by monitoring changes that occur with increasing age and pubertal stage. There were mainly positive influences variables of sex, maturity, height, weight and BMI, with similar data when compared to the gold standard method, the DXA.

A comparative study of dual-X-ray absorptiometry and quantitative ultrasonography for the evaluating bone status in subjects with Rett syndrome

Rett syndrome, an X-linked neurodevelopmental disorder primarily affecting girls, is frequently characterized by a reduced bone mineral density (BMD) with an increased risk of fragility fractures. The aim of the study was to assess bone status by DXA technique and by quantitative ultrasound (QUS) in subjects with Rett syndrome and to evaluate which DXA or QUS parameters better correlate with clinical features. In 156 Rett subjects (mean age 13.6 ± 8.2 years) and in 62 controls, we measured BMD at femoral neck (BMD-FN) and at total femur (BMD-TF). Apparent volumetric bone mineral density (vBMAD) was also calculated. In all subjects, QUS parameters at phalanges by Bone Profiler-IGEA (amplitude-dependent speed of sound: AD-SoS and bone transmission time: BTT) were evaluated. We found that both DXA parameters and QUS parameters were significantly lower in Rett subjects than in controls. All clinical characteristics were positively correlated to BMD-FN, BMD-TF, AD-SoS, and BTT (p < 0.001) but not with vBMAD-FN. All ultrasonographic parameters were significantly correlated to BMD-FN and BMD-TF, whereas vBMAD-FN showed only positive significant correlation with densitometric parameters (p < 001). In Rett subjects BMD-FN was predicted primarily by weight and movement capacity, whereas vBMAD-FN was predicted by weight, height, and calcium intake. Moreover, AD-SoS was predicted by weight, height, and age, while BTT was predicted only by height. In conclusion, in our study the performance of QUS at phalanges was similar to those of BMD at femur, therefore, both areal BMD at femur and QUS at phalanges (AD-SoS and BTT) may be equally useful in the evaluation of skeletal status in Rett patients.

Treatment of osteoporosis in children with glucocorticoid-treated diseases

Glucocorticoid induced osteoporosis (GIO) is the most frequent form of drug induced osteoporosis. Glucocorticoids affect osteoblastogenesis, osteoclastogenesis and promote the apoptosis of osteoblasts and osteocytes. A decrease of bone mineral density has been described in several pediatric diseases that require glucocorticoids, both as long-term replacement therapy, such as Congenital Adrenal Hyperplasia, and as treatment of acute phase or relapses, such as asthma, juvenile rheumatoid arthritis, inflammatory bowel diseases, systemic lupus erythematosus, organ transplantation and Steroid Sensitive Nephrotic Syndrome. The increasing number of children with GIO and at risk of fractures reflects the complex nature of this condition, and the need of development of anti-osteoporotic drugs. In this review, we focus on the mechanisms of GIO in some pediatric diseases and on treatment of osteoporosis. We also report data on new signaling pathways as potential targets for future anti-osteoporotic drugs.

Quantitative ultrasound at the phalanges in a cohort of monozygotic twins of different ages

PURPOSE

The aim of our study was to evaluate bone quality by quantitative ultrasound (QUS) at the phalanges in 129 monozygotic twin couples, outlining the differences between growing subjects and adults.

MATERIALS AND METHODS

A total of 129 healthy monozygotic twin couples (42 of children under 18 years of age and 87 of adults) were studied by phalangeal QUS, measuring amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT). Anthropometric data were also recorded.

RESULTS

In children AD-SoS and BTT were positively correlated with age (r = 0.91, r = 0.91), height (r = 0.88, r = 0.90) and weight (r = 0.81, r = 0.87); in adults AD-SoS was negatively related to age (r = -0.36), AD-SoS and BTT were positively related to height (r = 0.37, r = 0.58). Absolute value differences between twins for AD-SoS and BTT were significantly higher in adult twins (25.9 ± 21.9 for AD-SoS and 0.08 ± 0.08 for BTT) than in children (14.5 ± 12.4 for AD-SoS and 0.05 ± 0.04 for BTT).

CONCLUSION

Differentiation in bone tissue quality in twins increases with age, probably reflecting lifestyle, personal habits, likely acting through epigenetic mechanisms.

Comparison of bone mass and quality determinants in adolescents and young adults with juvenile systemic lupus erythematosus (JSLE) and juvenile idiopathic arthritis (JIA)

BACKGROUND

Few prospective data have been published on the comparison of bone density and quality in homogeneous groups of patients with juvenile systemic lupus erythematosus (JSLE) and juvenile idiopathic arthritis (JIA).

OBJECTIVE AND HYPOTHESIS

The objective of this study is to perform a longitudinal evaluation of the prevalence and the characteristics of bone mass and quality and to evaluate the differences on the bone parameters, using DXA, pQCT and QUS.

POPULATION AND/OR METHODS

Forty-three JSLE patients (35 females, 8 males, median age 18.8, range 14.0-34.1 years) have been studied with DXA, pQCT and QUS scans and compared with 138 JIA patients (112 females, 26 males, median age 18.9, range 13.4-33.2 years), and 79 controls (59 females, 20 males; median age 19.3, range 13.5-36.5 years). Of these, 39 patients (32 females and 7 males, median age 20.3, range 16.6-36.8 years) with JSLE were followed longitudinally and compared with 131 patients (108 females, 23 males median age 20.7, range 15.8-37.1 years) with JIA and 63 controls (48 females, 15 males; median age 21.9, range 15.5-38.3 years).

RESULTS

JSLE patients have a higher bone cortical density (CrtBMD) than controls and JIA patients (p < 0.005). However, JSLE and JIA patients have a significantly reduced bone trabecular density (TrbBMD) compared to controls (p < 0.0001), with no differences between JSLE and JIA. In addition, JIA patients show a significantly reduced muscle area (MuscleCSA) compared to JSLE and controls (p < 0.001). Conversely, fat area (FatCSA) is significantly increased both in JIA and JSLE patients when compared to controls (p < 0.001), with no differences between the JSLE and JIA groups. Analogous results are observed in the polar resistance to stress (SSIp). On longitudinal evaluation, contrary to CrtBMD, the difference between BMAD SDS, TrbBMD, MuscleCSA and FatCSA remains unchanged; in JSLE patients, SSIp is stable in comparison to JIA and controls without any difference between the two groups.

CONCLUSIONS

The evaluation of bone density and structure parameters in JSLE patients highlights significant differences compared with JIA patients and controls. These data might indicate a different pathogenesis of bone damage in the two entities, and suggest a different diagnostic and therapeutic approach to improve the peak bone mass.

Performance of phalangeal quantitative ultrasound parameters in the evaluation of reduced bone mineral density assessed by DX in patients with 21 hydroxylase deficiency

The purpose of this study was to verify the performance of quantitative ultrasound (QUS) parameters of proximal phalanges in the evaluation of reduced bone mineral density (BMD) in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21 OHD). Seventy patients with 21 OHD (41 females and 29 males), aged between 6-27 y were assessed. The QUS measurements, amplitude-dependent speed of sound (AD-SoS), bone transmission time (BTT), and ultrasound bone profile index (UBPI) were obtained using the BMD Sonic device (IGEA, Carpi, Italy) on the last four proximal phalanges in the non-dominant hand. BMD was determined by dual energy X-ray (DXA) across the total body and lumbar spine (LS). Total body and LS BMD were positively correlated to UBPI, BTT and AD-SoS (correlation coefficients ranged from 0.59-0.72, p < 0.001). In contrast, when comparing patients with normal and low (Z-score < -2) BMD, no differences were found in the QUS parameters. Furthermore, UBPI, BTT and AD-SoS measurements were not effective for diagnosing patients with reduced BMD by receiver operator characteristic curve parameters. Although the AD-SoS, BTT and UBPI showed significant correlations with the data obtained by DXA, they were not effective for diagnosing reduced bone mass in patients with 21 OHD.

Bone mass and quality in patients with juvenile idiopathic arthritis: longitudinal evaluation of bone-mass determinants by using dual-energy x-ray absorptiometry, peripheral quantitative computed tomography, and quantitative ultrasonography

Introduction

Our objective was to evaluate longitudinally the main bone-mass and quality predictors in young juvenile idiopathic arthritis (JIA) patients by using lumbar spine dual-energy X-ray absorptiometry (DXA) scan, radius peripheral quantitative computed tomography (pQCT), and phalangeal quantitative ultrasonography (QUS) at the same time.

Methods

In total, 245 patients (172 females, 73 males; median age, 15.6 years: 148 oligoarticular, 55 polyarticular, 20 systemic, and 22 enthesitis-related-arthritis (ERA) onset) entered the study. Of these, 166 patients were evaluated longitudinally. Data were compared with two age- and sex-matched control groups.

Results

In comparison with controls, JIA patients, but not with ERA, had a reduced spine bone-mineral apparent density (BMAD) standard deviation score (P < 0.001) and musculoskeletal deficits, with significantly lower levels of trabecular bone mineral density (TrabBMD) (P < 0.0001), muscle cross-sectional area (CSA) (P < 0.005), and density-weighted polar section modulus (SSIp) (P < 0.05). In contrast, JIA showed fat CSA significantly higher than controls (P < 0.0001). Finally, JIA patients had a significant reduced amplitude-dependent speed of sound (AD-SoS) (P < 0.001), and QUS z score (P < 0.005).

Longitudinally, we did not find any difference in all JIA patients in comparison with baseline, except for the SSIp value that normalized. Analyzing the treatments, a significant negative correlation among spine BMAD values, TrabBMD, AD-SoS, and systemic and/or intraarticular corticosteroids, and a positive correlation among TNF-α-blocking agents and spine BMAD, TrabBMD, and AD-SoS were observed.

Conclusions

JIA patients have a low bone mass that, after a first increase due to the therapy, does not reach the normal condition over time. The pronounced bone deficits in JIA are greater than would be expected because of reduction in muscle cross-sectional area. Thus, bone alterations in JIA likely represent a mixed defect of bone accrual and lower muscle forces.

Osteoclastogenic potential of peripheral blood mononuclear cells in cleidocranial dysplasia

Cleidocranial dysplasia (CCD) is an autosomal dominant skeletal dysplasia characterized by hypoplastic or aplastic clavicles, dental abnormalities, and delayed closure of the cranial sutures. In addition, mid-face hypoplasia, short stature, skeletal anomalies and osteoporosis are common. We aimed to evaluate osteoclastogenesis in a child (4 years old), who presented with clinical signs of CCD and who have been diagnosed as affected by deletion of RUNX2, master gene in osteoblast differentiation, but also affecting T cell development and indirectly osteoclastogenesis. The results of this study may help to understand whether in this disease is present an alteration in the bone-resorptive cells, the osteoclasts (OCs). Unfractionated and T cell-depleted Peripheral Blood Mononuclear Cells (PBMCs) from patient were cultured in presence/absence of recombinant human M-CSF and RANKL. At the end of the culture period, OCs only developed following the addition of M-CSF and RANKL. Moreover, real-time PCR experiment showed that freshly isolated T cells expressed the osteoclastogenic cytokines (RANKL and TNFα) at very low level, as in controls. This is in accordance with results arising from flow cytometry experiments demonstrating an high percentage of circulating CD4(+)CD28(+) and CD4(+)CD27(+) T cells, not able to produce osteoclastogenic cytokines. Also RANKL, OPG and CTX serum levels in CCD patient are similar to controls, whereas QUS measurements showed an osteoporotic status (BTT-Z score -3.09) in the patient. In conclusions, our findings suggest that the heterozygous deletion of RUNX2 in this CCD patient did not alter the osteoclastogenic potential of PBMCs in vitro.

Cross-sectional and longitudinal evaluation of bone mass and quality in children and young adults with juvenile onset systemic lupus erythematosus (JSLE): role of bone mass determinants analyzed by DXA, PQCT and QUS

INTRODUCTION

There are few prospective data on bone mass and quality in patients with juvenile onset systemic lupus erythematosus (JSLE). There are also few studies analyzing bone mass and quality determinants by using at the same time dual-energy X-ray absorptiometry (DXA), peripheral quantitative computed tomography (pQCT) and quantitative ultrasound (QUS).

OBJECTIVE

The objective of this paper is to evaluate cross-sectionally and longitudinally bone mass and quality determinants in adolescents and young adults with JSLE, and to identify the main predictors of reduced bone mineral density (BMD) and bone quality using these techniques.

METHODS

Fifty-six patients with JSLE (mean age 18.5 ± 5.7 years) entered the study. In all subjects DXA scan at the lumbar spine, radius pQCT and phalangeal QUS were performed the same day. Of these, 46 patients (mean age 23.1 ± 6.2 years) were revaluated with a second DXA, pQCT and QUS. The data obtained were compared with 72 and 80 age- and sex- matched healthy controls.

RESULTS

At the first evaluation, JSLE patients had a reduced spine BMAD SDS (p < 0.001), and significantly lower levels of TrabBMD (p < 0.0001), SSIp (p < 0.05), AD-SoS and QUS z-score (p < 0.005) but not reduced muscle CSA and CBA values. CortBMD and FatCSA were significantly increased (p < 0.0001). These data were confirmed at longitudinal evaluation regarding spine BMAD SDS (p < 0.001), TrabBMD (p < 0.0001), FatCSA (p < 0.005), AD-SoS (p < 0.001), and QUS z-score (p < 0.005) but not muscle CSA (p ≤ 0.05) and CBA (p < 0.0001). SSIp and CortBMD longitudinal evaluation showed that JSLE patients did not present significant differences in comparison to controls.

CONCLUSIONS

Patients with JSLE have a low bone mass without catch-up growth over time, causing a reduction of peak bone mass with high risk of osteoporosis in early adulthood. To reduce the risk, close monitoring of BMD, better control of disease activity, physical activity and dietary intake of calcium and vitamin D are advocated to ameliorate the loss of bone mass. In patients with proved osteoporosis therapeutic approaches including bisphosphonates should be considered.

Pamidronate treatment stimulates the onset of recovery phase reducing fracture rate and skeletal deformities in patients with idiopathic juvenile osteoporosis: comparison with untreated patients

Although spontaneous remission occurs in patients with idiopathic juvenile osteoporosis (IJO), permanent bone deformities may occur. The effects of long-term pamidronate treatment on clinical findings, bone mineral status, and fracture rate were evaluated. Nine patients (age 9.8 ± 1.1 years, 7 males) with IJO were randomized to intravenous pamidronate (0.8 ± 0.1 mg/kg per day for 3 days; cycles per year 2.0 ± 0.1; duration 7.3 ± 1.1 years; n = 5) or no treatment (n = 4). Fracture rate, phalangeal quantitative ultrasound, and lumbar bone mineral density (BMD) by dual energy X-ray absorptiometry at entry and during follow-up (range 6.3-9.4 years) were assessed. Bone pain improved in treated patients. Difficulty walking continued for 3-5 years in untreated patients, and vertebral collapses occurred in three of them. During follow-up, phalangeal amplitude-dependent speed of sound (AD-SoS), bone transmission time (BTT), and lumbar BMDarea and BMDvolume progressively increased in treated patients (P < 0.05-P < 0.0001). In untreated patients AD-SoS and BTT decreased during the first 2-4 years of follow-up (P < 0.05-P < 0.01); lumbar BMDarea increased after 6 years (P < 0.001) whereas BTT and lumbar BMDvolume increased after 7 years of follow-up (P < 0.05 and P < 0.001, respectively). At the end of follow-up, AD-SoS, BTT, lumbar BMDarea, and BMDvolume Z-scores were lower in untreated patients than in treated patients (-2.2 ± 0.3 and -0.5 ± 0.2; -1.9 ± 0.2 and -0.6 ± 0.2; -2.3 ± 0.3 and -0.7 ± 0.3; -2.4 ± 0.2 and -0.7 ± 0.3, P < 0.0001, respectively). Fracture rate was higher in untreated patients than in treated patients during the first 3 years of follow-up (P < 0.02). Our study showed that spontaneous recovery of bone mineral status is unsatisfactory in patients with IJO. Pamidronate treatment stimulated the onset of recovery phase reducing fracture rate and permanent disabilities without evidence of side-effects.

Quantitative ultrasound applied to metacarpal bone in infants

Aim. To provide bone status assessment in infancy using quantitative ultrasound (QUS) applied to second metacarpus.

Methods. 103 healthy term infants and 3 patients with rickets, aged ≤ 12 months, underwent metacarpal QUS evaluation using QUS DBM Sonic Aurora IGEA (MO, Italy), which measures speed of sound (mcSOS) and bone transmission time (mcBTT).

Results. In the total sample, median (interquartile range) of mcSOS was 1640.00 (26.0) m/s and mcBTT 0.82 (0.21) µs. Moreover, reference values for age were obtained based on estimation of the lower and upper percentiles. We observed a statistical significant difference between groups of age for mcSOS (p = 0.016). In a multiple linear regression model, we found a relation between age at enrolment and mcSOS (β = −0.608; p = 0.000) and mcBTT (β = −0.819; p = 0.001). A positive correlation between mcSOS and mcBTT has been observed (r = 0.631; p = 0.000). All the patients with rickets showed values of mcSOS and mcBTT lower than the 10th percentile.

Conclusion. Our findings show that this new simple technique appears to be a promising tool for monitoring bone mineral status in pediatric clinical practice and in early life. Furthermore, it could be considered a useful method to investigate and to monitor the role of different factors on programming of bone health and it should be tested as a new method for monitoring subjects with rickets during therapy.

The ability of lumbar spine DXA and phalanx QUS to detect previous fractures in young thalassemic patients with hypogonadism, hypothyroidism, diabetes, and hepatitis-B: A 2-year subgroup analysis from the Taranto Area of Apulia Region

BACKGROUND

Osteoporosis is a leading cause of morbidity in patients affected by β-thalassemia major or intermediate; we aimed to assess the association between demineralization observed in young thalassemic patients.

METHODS

A total of 88 patients with β-thalassemia were recruited at Microcitemia Center of Taranto Hospital under the Prevention Osteoporosis and Fractures research project from 2008 to 2010. All the patients were screened with both dual energy x-ray absorptiometry (DXA) and quantitative ultrasound (QUS). T score and Z score values were obtained for each subject.

RESULTS

The overall prevalence of demineralization was 84% with DXA and 70% with QUS, whereas normality was found in 16% of patients screened with DXA and in 30% of cases with QUS. Hypogonadism, hypothyroidism, diabetes mellitus, hepatitis-B, and the presence of previous fragility fractures were significantly associated with the demineralization status (lower T scores values) both with DXA and QUS.

CONCLUSION

Our data confirm that DXA and QUS examinations are both useful for detecting bone demineralization in thalassemic patients.

Bone health in children with long-term idiopathic subclinical hypothyroidism

Background

Subclinical hypothyroidism (SH) is a relatively common condition characterized by a mild persistent thyroid failure. The management of children with SH is still a controversial issue and the decision to treat with L-thyroxine represents a clinical dilemma. Thyroid hormone and TSH play an important role in skeletal growth and bone mineral homeostasis.

Aim

To evaluate whether untreated idiopathic SH may affect bone health in childhood and to compare two different diagnostic tools such as dual-energy X-ray densitometry (DXA) and quantitative ultrasound (QUS).

Patients and Methods

Twenty-five children and adolescents (11 males) aged 9.8 ± 3.5 years (range 4.2-18.7) with untreated idiopathic SH were enrolled in the study. SH was diagnosed on the basis of normal FT4 levels with TSH concentrations between 4.2 and 10 mU/l. Children have been followed for 3.3 ± 0.3 years from the time of SH diagnosis. Twenty-five healthy children, age- and sex-matched, were enrolled as controls. Patients and controls underwent DXA to evaluate lumbar spine bone mineral density (BMD) and QUS at proximal phalanges of the non-dominant hand to assess bone quality, measured as amplitude-dependent speed of sound (Ad-SoS) and bone transmission time (BTT).

Results

Mean BMD Z-score was −0.4 ± 1.36 in patients and −0.2 ± 1.2 in controls. Mean Ad-SoS Z-score was 0.01 ± 1.0 in patients and 0.1 ± 1.2 in controls and mean BTT Z-score was −0.03 ± 0.8 and 0.04 ± 1.1 respectively. All values were within the normal range, both in patients and in controls. There were no statistically significant differences between the two groups.

Conclusion

Bone health, evaluated by lumbar spine DXA and phalangeal QUS, is not impaired in our children, despite long-term duration of idiopathic SH. Data about bone status provided by QUS are comparable to those provided by DXA. Therefore, QUS may represent a good, cheaper and safe screening test for bone evaluation in children with SH.

Relationship between markers of body fat and calcaneal bone stiffness differs between preschool and primary school children: results from the IDEFICS baseline survey

The aim of this study was to investigate the relationship between markers of body fat and bone status assessed as calcaneal bone stiffness in a large sample of European healthy pre- and primary school children. Participants were 7,447 children from the IDEFICS study (spread over eight different European countries), age 6.1 ± 1.8 years (range 2.1-9.9), 50.5 % boys. Anthropometric measurements (weight, height, bioelectrical impedance, waist and hip circumference, and tricipital and subscapular skinfold thickness) as well as quantitative ultrasonographic measurements to determine calcaneal stiffness index (SI) were performed. Partial correlation analysis, linear regression analysis, and ANCOVA were stratified by sex and age group: preschool boys (n = 1,699) and girls (n = 1,599) and primary school boys (n = 2,062) and girls (n = 2,087). In the overall study population, the average calcaneal SI was equal to 80.2 ± 14.0, ranging 42.4-153. The results showed that preschool children with higher body fat had lower calcaneal SI (significant correlation coefficients between -0.05 and -0.20), while primary school children with higher body fat had higher calcaneal SI (significant correlation coefficients between 0.05 and 0.13). After adjusting for fat-free mass, both preschool and primary school children showed an inverse relationship between body fat and calcaneal stiffness. To conclude, body fat is negatively associated with calcaneal bone stiffness in children after adjustment for fat-free mass. Fat-free mass may confound the association in primary school children but not in preschool children. Muscle mass may therefore be an important determinant of bone stiffness.