Glucocorticoid-induced osteoporosis in children: impact of the underlying disease

Changes in bone turnover markers after discontinuing long-term glucocorticoid administration in children with idiopathic nephrotic syndrome: a multicenter retrospective observational study

BACKGROUND

Glucocorticoids affect bone turnover. Little is known about how bone turnover changes when glucocorticoids are discontinued following long-term administration.

METHODS

This retrospective observational study was conducted on the relationship between discontinuation of long-term administration of glucocorticoid and bone turnover markers (BTMs) in patients with childhood-onset idiopathic nephrotic syndrome. Serum bone alkaline phosphatase (BAP), intact procollagen type 1 N-terminal propeptide (P1NP), and tartrate-resistant acid phosphatase-5b (TRACP-5b) were evaluated as BTMs.

RESULTS

Thirty-eight pairs of BTMs at glucocorticoid administration and after discontinuation were analyzed in 29 patients. The median age at baseline was 12.4 (interquartile range, 9.0-14.5) years, and the median time from the onset of nephrotic syndrome was 5.9 (3.3-9.7) years. The mean period from prednisolone discontinuation to the measurement of BTMs after glucocorticoid discontinuation was 3.5 ± 1.0 months. Changes in BTMs after glucocorticoid discontinuation were modest when the daily prednisolone dose was < 0.25 mg/kg/day (ln BAP standard deviation [SD] score, p = 0.19; log intact P1NP SD score, p = 0.70; TRACP-5b, p = 0.95). When the daily prednisolone dose was ≥ 0.25 mg/kg/day, all BTMs increased significantly after glucocorticoid discontinuation (ln BAP SD score, p < 0.01; log intact P1NP SD score, p < 0.01; TRACP-5b, p < 0.01).

CONCLUSIONS

Decreased BTMs can rise within a few months of discontinuing long-term glucocorticoid administration. When the administered glucocorticoid dose is low, changes in BTMs may be small. A higher resolution version of the Graphical abstract is available as Supplementary information.

Relationship between risk factors for impaired bone health and HR-pQCT in young adults with type 1 diabetes

OBJECTIVE

In type 1 diabetes, risk factors associated with impaired bone health contribute to increased risk of fracture. The aim of this study was to (1): compare the high-resolution peripheral quantitative computed tomography (HR-pQCT) parameters of young adults with type 1 diabetes with those of healthy controls (2), identify sex differences, and (3) evaluate the association between diabetes and bone health risk factors, with HR-pQCT.

METHODS

This is a cross-sectional study in young Canadian adults with childhood onset type 1 diabetes. Z-scores were generated for HR-pQCT parameters using a large healthy control database. Diet, physical activity, BMI, hemoglobin A1C (A1C) and bone health measures were evaluated, and associations were analyzed using multivariate regression analysis.

RESULTS

Eighty-eight participants (age 21 ± 2.2 years; 40 males, 48 females, diabetes duration 13.9 ± 3.4 years) with type 1 diabetes were studied. Low trabecular thickness and elevated cortical geometry parameters were found suggesting impaired bone quality. There were no sex differences. Significant associations were found: Vitamin D (25(OH)D) with trabecular parameters with possible synergy with A1C, parathyroid hormone with cortical parameters, BMI with cortical bone and failure load, and diabetes duration with trabecular area.

CONCLUSIONS

Our data suggests impairment of bone health as assessed by HR-pQCT in young adults with type 1 diabetes. Modifiable risk factors were associated with trabecular and cortical parameters. These findings imply that correction of vitamin D deficiency, prevention and treatment of secondary hyperparathyroidism, and optimization of metabolic control may reduce incident fractures.

Persistent Musculoskeletal Deficits in Pediatric, Adolescent and Young Adult Survivors of Allogeneic Hematopoietic Stem-Cell Transplantation

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is a common therapy for pediatric hematologic malignancies. With improved supportive care, addressing treatment-related late effects is at the forefront of survivor long-term health and quality of life. We previously demonstrated that alloHSCT survivors had increased adiposity, decreased lean mass, and lower bone density and strength, 7 years (median) from alloHSCT compared to their healthy peers. Yet it is unknown whether these deficits persist. Our longitudinal study characterized changes in muscle and bone over a period of 3.4 (range, 2.0 to 4.9) years in 47 childhood alloHSCT survivors, age 5-26 years at baseline (34% female). Tibia cortical bone geometry and volumetric density and lower leg muscle cross-sectional area (MCSA) were assessed via peripheral quantitative computed tomography (pQCT). Anthropometric and pQCT measurements were converted to age, sex, and ancestry-specific standard deviation scores, adjusted for leg length. Muscle-specific force was assessed as strength relative to MCSA adjusted for leg length (strength Z-score). Measurements were compared to a healthy reference cohort (n = 921), age 5-30 years (52% female). At baseline and follow-up, alloHSCT survivors demonstrated lower height Z-scores, weight Z-scores, and leg length Z-scores compared to the healthy reference cohort. Deficits in MCSA, trabecular volumetric bone density, and cortical bone size and estimated strength (section modulus) were evident in survivors (all p < 0.05). Between the two study time points, anthropometric, muscle, and bone Z-scores did not change significantly in alloHSCT survivors. Approximately 15% and 17% of alloHSCT survivors had MCSA and section modulus Z-score < -2.0, at baseline and follow-up, respectively. Furthermore, those with a history of total body irradiation compared to those without demonstrated lower MCSA at follow-up. The persistent muscle and bone deficits in pediatric alloHSCT survivors support the need for strategies to improve bone and muscle health in this at-risk population. © 2022 American Society for Bone and Mineral Research (ASBMR).

Osteoporosis Due to Hormone Imbalance: An Overview of the Effects of Estrogen Deficiency and Glucocorticoid Overuse on Bone Turnover

Osteoporosis is a serious health issue among aging postmenopausal women. The majority of postmenopausal women with osteoporosis have bone loss related to estrogen deficiency. The rapid bone loss results from an increase in bone turnover with an imbalance between bone resorption and bone formation. Osteoporosis can also result from excessive glucocorticoid usage, which induces bone demineralization with significant changes of spatial heterogeneities of bone at microscale, indicating potential risk of fracture. This review is a summary of current literature about the molecular mechanisms of actions, the risk factors, and treatment of estrogen deficiency related osteoporosis (EDOP) and glucocorticoid induced osteoporosis (GIOP). Estrogen binds with estrogen receptor to promote the expression of osteoprotegerin (OPG), and to suppress the action of nuclear factor-κβ ligand (RANKL), thus inhibiting osteoclast formation and bone resorptive activity. It can also activate Wnt/β-catenin signaling to increase osteogenesis, and upregulate BMP signaling to promote mesenchymal stem cell differentiation from pre-osteoblasts to osteoblasts, rather than adipocytes. The lack of estrogen will alter the expression of estrogen target genes, increasing the secretion of IL-1, IL-6, and tumor necrosis factor (TNF). On the other hand, excessive glucocorticoids interfere the canonical BMP pathway and inhibit Wnt protein production, causing mesenchymal progenitor cells to differentiate toward adipocytes rather than osteoblasts. It can also increase RANKL/OPG ratio to promote bone resorption by enhancing the maturation and activation of osteoclast. Moreover, excess glucocorticoids are associated with osteoblast and osteocyte apoptosis, resulting in declined bone formation. The main focuses of treatment for EDOP and GIOP are somewhat different. Avoiding excessive glucocorticoid use is mandatory in patients with GIOP. In contrast, appropriate estrogen supplement is deemed the primary treatment for females with EDOP of various causes. Other pharmacological treatments include bisphosphonate, teriparatide, and RANKL inhibitors. Nevertheless, more detailed actions of EDOP and GIOP along with the safety and effectiveness of medications for treating osteoporosis warrant further investigation.

The Impact of Vitamin K2 (Menaquionones) in Children's Health and Diseases: A Review of the Literature

Vitamin K2 activates vitamin K-dependent proteins that support many biological functions, such as bone mineralization, the inhibition of vascular stiffness, the improvement of endothelial function, the maintenance of strong teeth, brain development, joint health, and optimal body weight. Due to the transformation of food habits in developed countries over the last five decades, vitamin K and, specifically, vitamin K2 intakes among parents and their offspring have decreased significantly, resulting in serious health implications. The therapeutics used in pediatric practice (antibiotics and glucocorticoids) are also to blame for this situation. Low vitamin K status is much more frequent in newborns, due to both endogenous and exogenous insufficiencies. Just after birth vitamin K stores are low, and since human milk is relatively poor in this nutrient, breast-fed infants are at particular risk of a bleeding disorder called vitamin K deficiency bleeding. A pilot study showed that better vitamin K status is associated with lower rate of low-energy fracture incidence. An ongoing clinical trial is intended to address whether vitamin K2 and D3 supplementation might positively impact the biological process of bone healing. Vitamin K2 as menaquinone-7 (MK-7) has a documented history of safe and effective use. The lack of adverse effects of MK-7 makes it the ideal choice for supplementation by pregnant and nursing women and children, both healthy and suffering from various malabsorptions and health disorders, such as dyslipidemia, diabetes, thalassemia major (TM), cystic fibrosis (CF), inflammatory bowel diseases (IBD), and chronic liver diseases. Additionally, worthy of consideration is the use of vitamin K2 in obesity-related health outcomes.

Novel function of adrenocorticotropic hormone in the stimulation of vascular endothelial growth factor release in healthy children and adolescents: a proof-of-concept study

PURPOSE

To assess the effect of adrenocorticotropic hormone (ACTH) on plasma vascular endothelial growth factor (VEGF) levels in healthy children and adolescents and to inform future work on the effects of ACTH on VEGF in bone.

METHODS

An Institutional Review Board-approved prospective study of 10 healthy subjects, ages 9-17, was conducted to assess the effect of ACTH on plasma VEGF levels. VEGF levels were collected at baseline and every 30 minutes for 3 hours. Cosyntropin (a synthetic ACTH analogue) was administered at a low-dose (1 μg) given at t=0 minutes and a high-dose (250 μg) given at t=60 minutes. A Friedman test was performed comparing baseline to peak VEGF levels after stimulation with low-dose and high-dose cosyntropin.

RESULTS

Peak plasma VEGF levels significantly increased after high-dose cosyntropin compared with baseline (P=0.042). Peak plasma VEGF levels did not significantly increase after low-dose cosyntropin compared to baseline.

CONCLUSION

To our knowledge, this is the first study to demonstrate that ACTH administration causes a significant increase in plasma VEGF levels in humans. This finding may have important implications in the protective effects of ACTH on bone. Decreased bone mineral density and adrenal suppression are common side effects of glucocorticoid use in pediatrics. VEGF increases vascularity and may play a role in reducing glucocorticoid-induced bone disease. Animal studies have shown that ACTH stimulates release of VEGF in osteoblasts, though this effect has yet to be evaluated in humans.

Methylprednisolone acetate mitigates IL1β induced changes in matrix metalloproteinase gene expression in skeletally immature ovine explant knee tissues

OBJECTIVE AND DESIGN

This study aimed at evaluating the effect of methylprednisolone (MPA) on messenger ribonucleic acid (mRNA) expression levels in immature ovine knee joint tissue explants following interleukin (IL)1β induction and to assess responsiveness of the explants.

MATERIAL OR SUBJECTS

Explants were harvested from the articular cartilage, synovium, and infrapatellar fat pad (IPFP) from immature female sheep.

TREATMENT

Methylprednisolone.

METHODS

The samples were allocated into six groups: (1) control, (2) MPA (10^-3 M), (3) MPA (10^-4 M), (4) IL1β, (5) IL1β + 10^-3 M MPA, or (6) IL1β + 10^-4 M MPA. mRNA expression levels for molecules relevant to inflammation, cartilage degradation/anabolism, activation of innate immunity, and adipose tissue/hormones were quantified. Fold changes with MPA treatment were compared via the comparative C_T method.

RESULTS

Methylprednisolone treatment significantly suppressed MMPs consistently across the cartilage (MMP1, MMP3, and MMP13), synovium (MMP1 and MMP3), and IPFP (MMP13) (all p < 0.05). Other genes that were less consistently suppressed include endogenous IL1β (cartilage) and IL6 (IPFP) (all p < 0.05), and others not affected either by IL-1 exposure or subsequent MPA include TGFβ1, TLR4, and adipose-related molecules.

CONCLUSIONS

Methylprednisolone significantly mitigated IL1β induced mRNA expression for MMPs in the immature cartilage, synovium, and IPFP, but the extent of the responsiveness was tissue-, location-, and gene-specific.

Pre-treatment with Pamidronate Improves Bone Mechanical Properties in Mdx Mice Treated with Glucocorticoids

Duchenne muscular dystrophy (DMD) is an X-linked disease of progressive muscle deterioration and weakness. Patients with DMD have poor bone health which is partly due to treatment with glucocorticoids, a standard therapy to prolong muscle function that also induces bone loss. Bisphosphonates are used to treat adults at risk of glucocorticoid-induced osteoporosis but are not currently used in DMD patients until after they sustain fractures. In this study, C57BL/10ScSn-mdx mice, a commonly used DMD animal model, received continuous glucocorticoid, prednisone treatment (0.083 mg/day) from 5 to 10 weeks of age. Pre-treatment with the bisphosphonate pamidronate started at 4 weeks of age over a period of 2 weeks or 6 weeks (cumulative dose 8 mg/kg for both) to assess the effectiveness of the two dosing regimens in ameliorating glucocorticoid-induced bone loss. Mdx mice treated with prednisone had improved muscle function that was not changed by pamidronate treatment. Glucocorticoid treatment caused cortical bone loss and decreased cortical bone strength. Both 2 and 6 week pamidronate treatment increased cortical thickness and bone area compared to prednisone-treated Mdx mice, however, only 2 week pamidronate treatment improved the strength of cortical bone compared to that of glucocorticoid-treated Mdx mice. In the trabecular bone, both pamidronate treatments significantly increased the amount of bone, and increased the ultimate load but not the energy to fail. These results highlight the importance of when and how much bisphosphonate is administered prior to glucocorticoid exposure.

Skeletal Morbidity in Children and Adolescents during and following Cancer Therapy

Skeletal abnormalities are common in children and adolescents diagnosed and treated for a malignancy. The spectrum ranges from mild pain to debilitating osteonecrosis and fractures. In this review, we summarize the impact of cancer therapy on the developing skeleton, provide an update on therapeutic strategies for prevention and treatment, and discuss the most recent advances in musculoskeletal research. Early recognition of skeletal abnormalities and strategies to optimize bone health are essential to prevent long-term skeletal sequelae and diminished quality of life in childhood cancer survivors.

Preservation of type H vessels and osteoblasts by enhanced preosteoclast platelet-derived growth factor type BB attenuates glucocorticoid-induced osteoporosis in growing mice

Survival of chronic diseases in childhood is often achieved utilizing glucocorticoids, but comes with significant side effects, including glucocorticoid-induced osteoporosis (GIO). Knowledge of the mechanism of GIO is limited to the adult skeleton. We explored the effect of genetic loss and inhibition of cathepsin K (Ctsk) as a potential treatment target in a young GIO mouse model as genetic loss of cathepsin K results in a mild form of osteopetrosis secondary to impaired osteoclast bone resorption with maintenance of bone formation. We first characterized the temporal osteoclast and osteoblast progenitor populations in Ctsk^-/- and wild type (WT) mice in the primary and secondary spongiosa, as sites representative of trabecular bone modeling and remodeling, respectively. In the primary spongiosa, Ctsk^-/- mice had decreased numbers of osteoclasts at young ages (2 and 4 weeks) and increased osteoblast lineage cells at later age (8 weeks) relative to WT littermates. In the secondary spongiosa, Ctsk^-/- mice had greater numbers of osteoclasts and osteoblast lineage cells relative to WT littermates. We next developed a young GIO mouse model with prednisolone 10 mg/m²/day injected intraperitoneally daily from 2 through 6 weeks of age. Overall, WT-prednisolone mice had lower bone volume per tissue volume, whereas Ctsk^-/--prednisolone mice maintained a similar bone volume relative to Ctsk^-/--vehicle controls. WT-prednisolone mice exhibited a decreased number of osteoclasts, tartrate-resistant acid phosphatase and platelet-derived growth factor type BB (PDGF-BB) co-positive cells, type H endothelial cells, and osteoblasts relative to WT-vehicle mice in both the primary and secondary spongiosa. Interestingly, Ctsk^-/--prednisolone mice demonstrated a paradoxical response with increased numbers of all parameters in primary spongiosa and no change in secondary spongiosa. Finally, treatment with a cathepsin K inhibitor prevented WT-prednisolone decline in osteoclasts, osteoblasts, type H vessels, and bone volume. These data demonstrate that cells in the primary and secondary spongiosa respond differently to glucocorticoids and genetic manipulation. Inhibition of osteoclast resorption that preserves osteoclast coupling factors, such as through inhibition of cathepsin K, may be a potential preventive treatment strategy against GIO in the growing skeleton.

Side effects of medications used to treat childhood interstitial lung disease

Interstitial lung disease in children (chILD) comprises a range of different rare diseases. There is limited evidence for the treatment of chILD and no randomised clinical trials of treatment have been undertaken. Most treatments are therefore prescribed off-label based on expert opinion. The off-label nature of prescription of drugs for chILD highlights the importance of a solid understanding of the side effects to facilitate risk-benefit assessment. The European Respiratory Society chILD guidelines recommend the use of systemic glucocorticosteroids, hydroxychloroquine and azithromycin. Side effects of these drugs will be discussed followed by consideration of other drugs used for the treatment of chILD.

Optimizing bone health in adolescents

PURPOSE OF REVIEW

The purpose is to provide a brief overview of factors that impact adolescent bone health and review special populations that deserve extra consideration of their bone health status.

RECENT FINDINGS

Optimization of modifiable factors is critical for adolescents to reach peak bone mass. Binge drinking, tobacco use, and certain medications all have accumulating evidence showing detrimental impacts on adolescent bone health and certain populations are more at risk for poorer bone health outcomes because of the nature of their conditions. Furthermore, very recent evidence suggests that in certain patients who have a history of insufficient nutritional and hormone status, 'catch-up' bone acquisition may not occur, underscoring the importance of early attention to these modifiable factors.

SUMMARY

Providers caring for adolescents should be aware of the many different populations at risk for poor bone health. Treatment that might further compromise bone health should be considered judiciously and providers should encourage optimization of any modifiable factor when possible.

Inflammatory Bowel Disease: Effects on Bone and Mechanisms

Inflammatory bowel disease (IBD) is associated with decreased bone mass and alterations in bone geometry from the time of diagnosis, before anti-inflammatory therapy is instituted. Deficits in bone mass can persist despite absence of symptoms of active IBD. The effects of IBD on the skeleton are complex. Protein-calorie malnutrition, inactivity, hypogonadism, deficits in calcium intake and vitamin D consumption and synthesis, stunted growth in children, decreased skeletal muscle mass, and inflammation all likely play a role. Preliminary studies suggest that the dysbiotic intestinal microbial flora present in IBD may also affect bone at a distance. Several mechanisms are possible. T cells activated by the gut microbiota may serve as "inflammatory shuttles" between the intestine and bone. Microbe-associated molecular patterns leaked into the circulation in IBD may activate immune responses in the bone marrow by immune cells and by osteocytes, osteoblasts, and osteoclasts that lead to decreased bone formation and increased resorption. Finally, intestinal microbial metabolites such as H₂S may also affect bone cell function. Uncovering these mechanisms will enable the design of microbial cocktails to help restore bone mass in patients with IBD.

Nutrition in Pediatric Inflammatory Bowel Disease: A Position Paper on Behalf of the Porto Inflammatory Bowel Disease Group of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition

BACKGROUND AND AIMS

A growing body of evidence supports the need for detailed attention to nutrition and diet in children with inflammatory bowel disease (IBD). We aimed to define the steps in instituting dietary or nutritional management in light of the current evidence and to offer a useful and practical guide to physicians and dieticians involved in the care of pediatric IBD patients.

METHODS

A group of 20 experts in pediatric IBD participated in an iterative consensus process including 2 face-to-face meetings, following an open call to Nutrition Committee of the European Society of Pediatric Gastroenterology, Hepatology and Nutrition Porto, IBD Interest, and Nutrition Committee. A list of 41 predefined questions was addressed by working subgroups based on a systematic review of the literature.

RESULTS

A total of 53 formal recommendations and 47 practice points were endorsed with a consensus rate of at least 80% on the following topics: nutritional assessment; macronutrients needs; trace elements, minerals, and vitamins; nutrition as a primary therapy of pediatric IBD; probiotics and prebiotics; specific dietary restrictions; and dietary compounds and the risk of IBD.

CONCLUSIONS

This position paper represents a useful guide to help the clinicians in the management of nutrition issues in children with IBD.

The effect of vitamin D and calcium supplementation in pediatric steroid-sensitive nephrotic syndrome

BACKGROUND

Low serum levels of total 25-hydroxycholecalciferol (25(OH)D) occur in nephrotic syndrome (NS). We aimed to assess the effects of vitamin D3 and calcium supplementation on 25(OH)D levels, bone mineralization, and NS relapse rate in children with steroid-sensitive NS.

METHODS

A randomized controlled trial (RCT) was performed in children with steroid-sensitive NS. The treatment group received vitamin D3 (60,000 IU orally, weekly for 4 weeks) and calcium supplements (500 to 1,000 mg/day for 3 months) after achieving NS remission. Blood samples for bone biochemistry were taken during relapse (T0), after 6 weeks (T1) and 6 months (T2) of randomization, whereas a lumbar DXA scan was performed at T0 and T2. Renal ultrasound was performed after study completion in the treatment group and in all patients with hypercalciuria.

RESULTS

Of the 48 initial recruits, 43 patients completed the study. Post-intervention, 25(OH)D levels showed significant improvements in the treatment group compared with controls at T1 (p < 0.001) and T2 (p < 0.001). However, this was not associated with differences in bone mineral content (BMC) (p = 0.44) or bone mineral density (BMD) (p = 0.64) between the groups. Additionally, there was no reduction in relapse number in treated patients (p = 0.54). Documented hypercalciuria occurred in 52% of patients in the treatment group, but was not associated with nephrocalcinosis.

CONCLUSIONS

Although supplementation with calcium and vitamin D improved 25(OH)D levels significantly, there was no effect on BMC, BMD or relapse rate over a 6-month follow-up. Occurrence of hypercalciuria mandates caution and appropriate monitoring if using such therapy. Appropriate dosage of vitamin D3 remains uncertain and studies examining biologically active vitamin D may provide answers.

Osteoporosis in Children with Chronic Illnesses: Diagnosis, Monitoring, and Treatment

PURPOSE OF REVIEW

Osteoporosis is an under-recognized complication of chronic illness in childhood. This review will summarize recent literature addressing the risk factors, evaluation, and treatment for early bone fragility.

RECENT FINDINGS

Criteria for the diagnosis of pediatric osteoporosis include the presence of low trauma vertebral fractures alone or the combination of low bone mineral density and several long bone fractures. Monitoring for bone health may include screening for vertebral fractures that are common but often asymptomatic. Pharmacologic agents should be offered to those with fragility fractures especially when spontaneous recovery is unlikely. Controversies persist about the optimal bisphosphonate agent, dose, and duration. Newer osteoporosis drugs have not yet been adequately tested in pediatrics, though clinical trials are underway. The prevalence of osteoporosis is increased in children with chronic illness. To reduce the frequency of fragility fractures requires increased attention to risk factors, early intervention, and additional research to optimize therapy and potentially prevent their occurrence.

Pediatric Non-Alcoholic Fatty Liver Disease

With the increase in the prevalence of obesity, non-alcoholic fatty liver disease (NAFLD) has become among the leading causes of chronic liver disease in the pediatric age group. Once believed to be a “two-hit process”, it is now clear that the actual pathophysiology of NAFLD is complex and involves multiple pathways. Moreover, NAFLD is not always benign, and patients with non-alcoholic steatohepatitis (NASH) are at increased risk of developing advanced stages of liver disease. It has also been shown that NAFLD is not only a liver disease, but is also associated with multiple extrahepatic manifestations, including cardiovascular diseases, type 2 diabetes, and low bone mineral density. Although the data is scarce in the pediatric population, some studies have suggested that long-term mortality and the requirement of liver transplantation will continue to increase in patients with NAFLD. More studies are needed to better understand the natural history of NAFLD, especially in the pediatric age group.

Balloon Kyphoplasty for Managing Intractable Pain in Pediatric Pathologic Vertebral Fractures

BACKGROUND

Vertebral compression fractures are a common result of osteoporosis and osteopenia secondary to steroid use and chemotherapy treatment. Balloon kyphoplasty is a treatment option with good to excellent results well described in adults. Although a few recent studies have been published regarding the use of kyphoplasty in children, no formal indication exists for the pediatric population. The purpose of this study is to describe the outcomes of 3 chronically ill children with intractable pain from vertebral compression fractures, managed with kyphoplasty.

METHODS

We retrospectively reviewed 3 pediatric patients who underwent balloon kyphoplasty for vertebral compression fractures secondary to chronic illness. Patient variables included age, sex, primary diagnosis and treatments, levels of vertebral fracture, and time elapsed from initial therapy to fracture. A numeric rating scale of 0 to 10 was used for patient-reported pain, before and after kyphoplasty. Preoperative and postoperative analgesic use and physical function were also described. Surgical variables included levels of kyphoplasty, operative time, and procedure-related complications.

RESULTS

The primary diagnoses were relapsed rhabdomyosarcoma, abdominal desmoplastic small round cell tumor, and IPEX-like (immune dysregulation, polyendrocrinopathy, enteropathy, X-linked) syndrome. All 3 patients were males, aged 12, 12, and 13, respectively, at the time of kyphoplasty. Pain scores were 8 to 9 preoperatively in 2 patients, severely affecting their physical function including independent walking. Excruciating back pain was a contributing factor to the respiratory distress of the third patient, who required elective intubation. All of the patients reported significant pain relief (range, 0 to 2) and improved physical function with kyphoplasty. The third patient was successfully extubated 1 week postoperatively and eventually returned to baseline activity. There were no complications related to kyphoplasty.

CONCLUSIONS

Balloon kyphoplasty seems to be safe in terminally ill children and may be a useful tool for managing intractable pain due to vertebral compression fractures.

LEVEL OF EVIDENCE

Level IV-retrospective case series.

Bone density in pediatric Crohn's disease: A cross-sectional observation from South India

BACKGROUND

Crohn's disease (CD) frequently manifests in the second and third decades of life. Malnutrition and corticosteroid therapy may affect bone mineralization and delay bone growth. Our aim was to study bone mineral density and factors associated low bone mineral density (BMD) in pediatric CD.

METHODS

A cross-sectional observational study in children with CD (aged 5 to <18 years) was done. Demographic and treatment details were noted. Vitamin D levels <20 ng/mL were considered as deficiency. Bone mineral density was evaluated with dual-energy X-ray absorptiometry (DEXA) scan and Z score of <-2 SD was considered as low BMD. Data was analyzed descriptively.

RESULTS

In 30 cases with CD enrolled over 1 year, mean age of the patients was 13.8±3.0 years. Age of onset and diagnosis was 11.4±3.2 years and 13.4±2.8 years, respectively. 73.3% were in the underweight category. All cases received azathioprine whereas 86.7% were receiving corticosteroids. Vitamin D deficiency was seen in 86.7% cases. A low BMD was evident in 70% children. Overall, low BMI (p=0.005) and vitamin D deficiency (p=0.005) were associated with low BMD. However, no association between severity grade of vitamin D deficiency and low BMD was found. Treatment with corticosteroid was associated with low BMD in 76.9% cases (p=0.069).

CONCLUSION

Low BMD was frequent in children with CD and was associated with low BMI and vitamin D deficiency.

Update on Bone Health in Pediatric Chronic Disease

Children and adolescents with chronic disease are predisposed to impaired bone health. Pediatric illness, including type 1 diabetes mellitus, celiac disease, and cystic fibrosis, have significant risk of low bone mineralization and fracture due to underlying inflammation, malabsorption, lack of physical activity, and delayed puberty. Dual-energy x-ray absorptiometry is the primary imaging method to assess bone health in this population. The purpose of this review is to update readers about the assessment and management of bone health in children with common pediatric chronic illnesses and review recent advances in the prevention and treatment of impaired bone health.

Glucocorticoids and Hospital Length of Stay for Children with Anaphylaxis: A Retrospective Study

OBJECTIVE

To evaluate whether glucocorticoid administration is associated with improved outcomes in children with anaphylaxis.

STUDY DESIGN

We included children from the Pediatric Health Information System database who were diagnosed with anaphylaxis at 35 US children's hospitals between 2009 and 2013. Patients were stratified by disposition from the emergency department (ED), either hospitalized or discharged. We evaluated the association between glucocorticoid administration and prolonged length of stay (LOS), defined as hospital stay ≥ 2 days, and subsequent epinephrine administration among hospitalized children. Among discharged children, we assessed the association between glucocorticoid administration and ED revisits within 3 days. Analyses were adjusted for illness severity using ordering of laboratory tests, medications, oxygen, intravenous fluids, and admission to the intensive care unit.

RESULTS

Among 5203 children hospitalized with anaphylaxis, 424 (8.2%) had prolonged LOS. Glucocorticoid administration was inversely associated with prolonged LOS (aOR, 0.61; 95% CI, 0.41-0.93) and with subsequent epinephrine use (aOR, 0.63; 95% CI, 0.43-0.84) among hospitalized children. Glucocorticoid administration was not associated with the odds of a 3-day revisit (aOR, 1.01; 95% CI, 0.50-2.05) among discharged patients.

CONCLUSION

The use of glucocorticoids was inversely associated with prolonged LOS among children hospitalized with anaphylaxis, but was not associated with 3-day ED revisits among discharged children. These findings support the use of glucocorticoids in children hospitalized with anaphylaxis.

Effect of glucocorticoids on growth and bone mineral density in children with nephrotic syndrome

Glucocorticosteroids (GCs) are the first-line treatment for idiopathic nephrotic syndrome (NS), but prolonged administration interferes with growth and bone mineralization. We conducted a retrospective study to analyze the long-term impact of prednisone on growth and bone mineral density (BMD) in children with NS. Data from children with NS followed during almost 10 years were analyzed. Height and spine BMD values were converted to Z-scores (standard deviation [SD]). The mean cumulative dose of GCs received was calculated and correlated to patient's growth and spine BMD using linear regression and subgroup analysis. We included 30 patients diagnosed at 3.7 years old (interquartile range (IQR) 2.6-4.8) and followed over 9.8 years (IQR 6.6-11.7). The one half of NS patients was steroid sensitive and one half dependent or resistant. The median cumulative dose of GCs received was 0.27 mg/kg/day (IQR 0.18-0.35). Growth and spine BMD were both negatively associated with the cumulative dose of GCs (P=0.001 and P=0.037, respectively). Final height Z-scores were significantly lower in patients receiving >0.2 mg/kg/day GCs (P=0.001). No difference was observed in spine BMD between subgroups.

CONCLUSION

Increasing doses of GCs were significantly associated with lower height and BMD Z-scores. A significant effect on growth was observed with cutoff doses above 0.2 mg/kg/day.

Prevention of glucocorticoid induced bone changes with beta-ecdysone

Beta-ecdysone (βEcd) is a phytoecdysteroid found in the dry roots and seeds of the asteraceae and achyranthes plants, and is reported to increase osteogenesis in vitro. Since glucocorticoid (GC) excess is associated with a decrease in bone formation, the purpose of this study was to determine if treatment with βEcd could prevent GC-induced osteoporosis. Two-month-old male Swiss-Webster mice (n=8-10/group) were randomized to either placebo or slow release prednisolone pellets (3.3mg/kg/day) and treated with vehicle control or βEcd (0.5mg/kg/day) for 21days. GC treatment inhibited age-dependent trabecular gain and cortical bone expansion and this was accompanied by a 30-50% lower bone formation rate (BFR) at both the endosteal and periosteal surfaces. Mice treated with only βEcd significantly increased bone formation on the endosteal and periosteal bone surfaces, and increased cortical bone mass were their controls to compare to GC alone. Concurrent treatment of βEcd and GC completely prevented the GC-induced reduction in BFR, trabecular bone volume and partially prevented cortical bone loss. In vitro studies determined that βEcd prevented the GC increase in autophagy of the bone marrow stromal cells as well as in whole bone. In summary, βEcd prevented GC induced changes in bone formation, bone cell viability and bone mass. Additional studies are warranted of βEcd for the treatment of GC induced bone loss.

Oral steroid therapy as an adjuvant treatment for severe epidemic keratoconjunctivitis in patients younger than 3 years

PURPOSE

To evaluate the therapeutic effect of oral steroids given to patients younger than 3 years with epidemic keratoconjunctivitis (EKC) accompanied by severe eyelid edema and inflammatory ptosis, in whom eye drops were not feasible.

METHODS

This study included 9 patients treated for EKC in local clinics whose condition failed to improve due to severe eyelid swelling together with difficulties in application of eye drops and pseudomembrane removal. We analyzed the extent of eyelid swelling, corneal damage, follicles, chemosis, and pseudomembrane formation in these patients before and after oral corticosteroid therapy in collaboration with the pediatrics department.

RESULTS

After a mean of 1.8 ± 0.7 days of oral steroid treatment, eyelid edema, corneal damage, conjunctival injection, follicles, and chemosis improved in all patients.

CONCLUSIONS

Oral steroids are an effective adjuvant treatment for EKC in patients younger than 3 years in whom eye drops could not be administered frequently due to severe eyelid edema.

Glucocorticoid-induced osteoporosis in growing rats

This study evaluated whether growing rats were appropriate animal models of glucocorticoid-induced osteoporosis. The 3-month-old male rats were treated with either vehicle or prednisone acetate at 1.5, 3.0, and 6.0 mg/kg/day by oral gavage, respectively. All rats were injected with tetracycline and calcein before sacrificed for the purpose of double in vivo labeling. Biochemistry, histomorphometry, mechanical test, densitometry, micro-CT, histology, and component analysis were performed. We found that prednisone treatments dose dependently decreased body weight, serum biomarkers, biomechanical markers, bone formation, and bone resorption parameters in both tibial and femoral trabecular bone without trabecular bone loss. We also found that significant bone loss happened in femoral cortical bone in the glucocorticoid-treated rats. The results suggested that prednisone not only inhibited bone formation, but also inhibited bone resorption which resulted in poor bone strength but with no cancellous bone loss in growing rats. These data also suggested that the effects of glucocorticoid on bone metabolism were different between cortical bone and trabecular bone, and different between tibia and femur. Growing rats may be a glucocorticoid-induced osteoporosis animal model when evaluated the effects of drugs upon juvenile patients exposed to GC for a long time.

Glucocorticoid-associated osteoporosis in chronic inflammatory diseases: epidemiology, mechanisms, diagnosis, and treatment

Children with chronic illnesses such as Juvenile Idiopathic Arthritis and Crohn's disease, particularly when taking glucocorticoids, are at significant risk for bone fragility. Furthermore, when childhood illness interferes with achieving normal peak bone mass, life-long fracture risk is increased. Osteopenia and osteoporosis, which is increasingly recognized in pediatric chronic disease, likely results from numerous disease- and treatment-related factors, including glucocorticoid exposure. Diagnosing osteoporosis in childhood is complicated by the limitations of current noninvasive techniques such as DXA, which despite its limitations remains the gold standard. The risk:benefit ratio of treatment is confounded by the potential for spontaneous restitution of bone mass deficits and reshaping of previously fractured vertebral bodies. Bisphosphonates have been used to treat secondary osteoporosis in children, but limited experience and potential long-term toxicity warrant caution in routine use. This article reviews the factors that influence loss of normal bone strength and evidence for effective treatments, in particular in patients with gastrointestinal and rheumatologic disorders who are receiving chronic glucocorticoid therapy.

Bone morbidity in childhood leukemia: epidemiology, mechanisms, diagnosis, and treatment

Skeletal abnormalities are commonly seen in children and adolescents with leukemia. The spectrum ranges from mild pain to debilitating osteonecrosis (ON) and fractures. In this review, we summarize the skeletal manifestations, provide an update on therapeutic strategies for prevention and treatment, and discuss the most recent advances in musculoskeletal research. Early recognition of skeletal abnormalities and strategies to optimize bone health are essential to prevent long-term skeletal sequelae and diminished quality of life observed in children and adolescents with leukemia.

Calcium and vitamin D for osteoprotection in children with new-onset nephrotic syndrome treated with steroids: a prospective, randomized, controlled, interventional study

BACKGROUND

There are no robust guidelines on strategies to prevent the adverse skeletal effects of glucocorticoids in children.

OBJECTIVES

To evaluate the role of prophylactic calcium and vitamin D on bone health in children with new-onset nephrotic syndrome (NS) treated with short-term (12 weeks), high-dose glucocorticoids.

METHODS

Prospective, randomized, controlled, single blind, interventional study conducted on 41 steroid-naïve pre-pubertal children (29 boys, 12 girls). All children received prednisolone for 12 weeks (60 mg/m(2)/day daily for 6 weeks, followed by 40 mg/m(2)/day alternate days for 6 weeks). Recruited children were randomized into the intervention group (IG; vitamin D 1,000 IU/day and elemental calcium 500 mg/day) and the control group (CG). Bone mineral content (BMC) and bone mineral density (BMD) at the lumbar spine (L1-L4) were estimated at baseline and at 12 weeks. Mean percentage changes in BMC and BMD in IG and CG were compared.

RESULTS

Children in the IG showed an increase of 11.2 % in BMC versus the CG, who showed an 8.9 % fall (p < 0.0001). Net intervention-attributable difference in BMC was 20.1 %. BMD increased in both groups (IG 2.8 % vs CG 0.74 %), but the difference was not statistically significant (p = 0.27).

CONCLUSIONS

Short-term, high-dose glucocorticoid therapy decreases the BMC of the lumbar spine in steroid-naïve children with NS. Vitamin D and calcium co-administration not only prevents this decline, but also enhances BMC of the lumbar spine.

A systematic review and meta-analysis of glucocorticoid-induced osteoporosis in children

OBJECTIVE

To summarize the published effects of systemic glucocorticoid therapy on bone mineral density (BMD) and fractures in children.

METHODS

We performed a systematic review and meta-analysis of existing literature, using Medline, CINAHL, and Cochrane databases to identify studies of BMD or fractures in children ≤18 years taking systemic glucocorticoid therapy. We excluded studies of inhaled glucocorticoids, chemotherapy, and organ transplantation. Two authors reviewed abstracts for inclusion, read full-text articles to extract data, and rated each study using the Downs-Black scale.

RESULTS

A total of 16 studies met eligibility criteria, including 10 BMD (287 children) and six fracture (37,819 children) studies. Spine BMD was significantly lower (-0.18; 95% CI = -0.25; -0.10 g/cm(2)) in children taking glucocorticoid therapy, compared to age- and gender-matched healthy controls. Spine BMD was also lower (-0.14; 95% CI = -0.27; 0.00 g/cm(2)) in children taking glucocorticoids, compared to children with the same disease not taking glucocorticoids. Incident clinical fracture rates varied from 2% to 33%. Morphometric vertebral fracture incidence ranged from 6% to 10%, and prevalence was 29-45%.

CONCLUSION

Published data suggest that children treated with glucocorticoid therapy have lower spine BMD compared to healthy children. Whether children receiving glucocorticoid therapy have lower spine BMD compared to children with milder disease not requiring such therapy is not certain. Clinical and morphometric vertebral fractures are common, although only one study assessed fracture rates in healthy controls. Additional well-designed, prospective studies are needed to evaluate the skeletal effects of glucocorticoid therapy in children.

Glucocorticoid-induced osteoporosis: an update on effects and management

Glucocorticoids remain a cornerstone of guideline-based management of persistent asthma and allergic diseases. Glucocorticoid-induced osteoporosis (GIO) is the most common iatrogenic cause of secondary osteoporosis and an issue of concern for physicians treating patients with inhaled or oral glucocorticoids either continuously or intermittently. Patients with GIO experience fragility fractures at better dual-energy x-ray absorptiometry T-scores than those with postmenopausal or age-related osteoporosis. This might be explained, at least in part, by the effects of glucocorticoids not only on osteoclasts but also on osteoblasts and osteocytes. Effective options to detect and manage GIO exist, and a management algorithm has been published by the American College of Rheumatology to provide treatment guidance for clinicians. This review will summarize GIO epidemiology and pathophysiology and assess the role of inhaled and oral glucocorticoids in asthmatic adults and children, with particular emphasis on the effect of such therapies on bone health. Lastly, we will review the American College of Rheumatology GIO guidelines and discuss diagnostic and therapeutic strategies to mitigate the risk of GIO and fragility fractures.

An official American Thoracic Society clinical practice guideline: classification, evaluation, and management of childhood interstitial lung disease in infancy

BACKGROUND

There is growing recognition and understanding of the entities that cause interstitial lung disease (ILD) in infants. These entities are distinct from those that cause ILD in older children and adults.

METHODS

A multidisciplinary panel was convened to develop evidence-based guidelines on the classification, diagnosis, and management of ILD in children, focusing on neonates and infants under 2 years of age. Recommendations were formulated using a systematic approach. Outcomes considered important included the accuracy of the diagnostic evaluation, complications of delayed or incorrect diagnosis, psychosocial complications affecting the patient's or family's quality of life, and death.

RESULTS

No controlled clinical trials were identified. Therefore, observational evidence and clinical experience informed judgments. These guidelines: (1) describe the clinical characteristics of neonates and infants (<2 yr of age) with diffuse lung disease (DLD); (2) list the common causes of DLD that should be eliminated during the evaluation of neonates and infants with DLD; (3) recommend methods for further clinical investigation of the remaining infants, who are regarded as having "childhood ILD syndrome"; (4) describe a new pathologic classification scheme of DLD in infants; (5) outline supportive and continuing care; and (6) suggest areas for future research.

CONCLUSIONS

After common causes of DLD are excluded, neonates and infants with childhood ILD syndrome should be evaluated by a knowledgeable subspecialist. The evaluation may include echocardiography, controlled ventilation high-resolution computed tomography, infant pulmonary function testing, bronchoscopy with bronchoalveolar lavage, genetic testing, and/or lung biopsy. Preventive care, family education, and support are essential.

Adipokines and C-reactive protein in relation to bone mineralization in pediatric nonalcoholic fatty liver disease

AIM: To investigate bone mineral density (BMD) in obese children with and without nonalcoholic fatty liver disease (NAFLD); and the association between BMD and serum adipokines, and high-sensitivity C-reactive protein (HSCRP).

METHODS: A case-control study was performed. Cases were 44 obese children with NAFLD. The diagnosis of NAFLD was based on magnetic resonance imaging (MRI) with high hepatic fat fraction (≥ 5%). Other causes of chronic liver disease were ruled out. Controls were selected from obese children with normal levels of aminotransferases, and without MRI evidence of fatty liver as well as of other causes of chronic liver diseases. Controls were matched (1- to 1-basis) with the cases on age, gender, pubertal stage and as closely as possible on body mass index-SD score. All participants underwent clinical examination, laboratory tests, and whole body (WB) and lumbar spine (LS) BMD by dual energy X-ray absorptiometry. BMD Z-scores were calculated using race and gender specific LMS curves.

RESULTS: Obese children with NAFLD had a significantly lower LS BMD Z-score than those without NAFLD [mean, 0.55 (95%CI: 0.23-0.86) vs 1.29 (95%CI: 0.95-1.63); P < 0.01]. WB BMD Z-score was also decreased in obese children with NAFLD compared to obese children with no NAFLD, though borderline significance was observed [1.55 (95%CI: 1.23-1.87) vs 1.95 (95%CI: 1.67-2.10); P = 0.06]. Children with NAFLD had significantly higher HSCRP, lower adiponectin, but similar leptin levels. Thirty five of the 44 children with MRI-diagnosed NAFLD underwent liver biopsy. Among the children with biopsy-proven NAFLD, 20 (57%) had nonalcoholic steatohepatitis (NASH), while 15 (43%) no NASH. Compared to children without NASH, those with NASH had a significantly lower LS BMD Z-score [mean, 0.27 (95%CI: -0.17-0.71) vs 0.75 (95%CI: 0.13-1.39); P < 0.05] as well as a significantly lower WB BMD Z-score [1.38 (95%CI: 0.89-1.17) vs 1.93 (95%CI: 1.32-2.36); P < 0.05]. In multiple regression analysis, NASH (standardized β coefficient, -0.272; P < 0.01) and HSCRP (standardized β coefficient, -0.192; P < 0.05) were significantly and independently associated with LS BMD Z-score. Similar results were obtained when NAFLD (instead of NASH) was included in the model. WB BMD Z-scores were significantly and independently associated with NASH (standardized β coefficient, -0.248; P < 0.05) and fat mass (standardized β coefficient, -0.224; P < 0.05).

CONCLUSION: This study reveals that NAFLD is associated with low BMD in obese children, and that systemic, low-grade inflammation may accelerate loss of bone mass in patients with NAFLD.

Age-of-onset-dependent influence of NOD2 gene variants on disease behaviour and treatment in Crohn's disease

Background

Influence of genetic variants in the NOD2 gene may play a more important role in disease activity, behaviour and treatment of pediatric- than adult-onset Crohn’s disease (CD).

Methods

85 pediatric- and 117 adult-onset CD patients were tested for the three main NOD2 CD-associated variants (p.R702W, p.G908R and p.10007fs) and clinical data of at least two years of follow-up were compared regarding disease behaviour and activity, response to therapy and bone mineral density (BMD).

Results

Chronic active and moderate to severe course of CD is associated in patients with pediatric-onset (p=0.0001) and NOD2 variant alleles (p=0.0001). In pediatric-onset CD the average PCDAI-Score was significantly higher in patients carrying NOD2 variants (p=0.0008). In addition, underweight during course of the disease (p=0.012) was associated with NOD2 variants. Interestingly, osteoporosis was found more frequently in patients carrying NOD2 variant alleles (p=0.033), especially in pediatric-onset CD patients with homozygous NOD2 variants (p=0.037). Accordingly, low BMD in pediatric-onset CD is associated with a higher PCDAI (p=0.0092), chronic active disease (p=0.0148), underweight at diagnosis (p=0.0271) and during follow-up (p=0.0109). Furthermore, pediatric-onset CD patients with NOD2 variants are more frequently steroid-dependent or refractory (p=0.048) and need long-term immunosuppressive therapy (p=0.0213).

Conclusions

These data suggests that the presence of any of the main NOD2 variants in CD is associated with osteoporosis and an age of onset dependent influence towards underweight, higher disease activity and a more intensive immunosuppressive therapy. This observation supports the idea for an early intensive treatment strategy in children and adolescent CD patients with NOD2 gene variants.

Prevention of steroid-induced low bone mineral density in children with renal diseases: a systematic review

BACKGROUND

Children with renal diseases who are treated with glucocorticoids are at increased risk of developing osteoporosis and fractures. However, there is no common strategy for prevention of corticosteroid-induced osteoporosis. The present systematic review was performed to determine whether prevention of bone loss by calcium (Ca), vitamin D (vit D) and/or bisphosphonates is justified, safe and efficacious in children treated with steroids for various renal diseases.

METHODS

DATA SOURCES

Medline, Embase, Central were searched from 1961 up to 2012. Randomized controlled trials (RCTs) and observational studies concerning children ≤18 years with renal diseases requiring steroids were included.

RESULTS

The search strategy retrieved 2482 studies. Four RCTs including 166 patients and one observational study including 100 children met our eligibility criteria. One RCT and the observational study concerned treatment with Ca/vit D, one RCT with bisphosphonates and two RCTs with a combination of both therapies. All described a significant improvement in bone mineral density (BMD) in the treatment group compared with the control group.

CONCLUSIONS

 Ca combined with vit D is recommended to prevent bone disease in children with renal diseases treated with steroids. Because of side effects, bisphosphonates should be reserved for the treatment of severe osteoporosis when Ca and/or vit D supplementation has failed.

Vitamin D status and bone density in steroid-treated children with glomerulopathies: effect of cholecalciferol and calcium supplementation

PURPOSE

The aim of this study was to assess vitamin D status and bone density in steroid-treated children with glomerulopathies and to evaluate the effect of prophylactic vitamin D and calcium supplementation.

MATERIAL AND METHODS

Retrospective analysis was performed on 55 children aged 4-18 yrs with glomerulopathies. The following data were analyzed: antropometrical parameters, bone densitometries, parathormone, 25-hydroxyvitamin D (25-OHD), urinary calcium excretion and medications received for prevention of low bone mass.

RESULTS

A significant number of children (38%) had decreased spinal bone mineral density (BMD z-score < -2.0) and the majority of them (89%) had hypovitaminosis D (25-OHD < 30 ng/ml), 75% were vitamin D insufficient (25-OHD < 20 ng/ml) and 16% were vitamin D deficient (25-OHD < 10 ng/ml). The mean serum 25-OHD concentration was comparable to that of controls (19.32 ± 12.87 vs. 15.05 ± 8.52 ng/ml). Nearly all patients (82%) were receiving preparations of calcium and/or vitamin D to improve bone health. Patients on cholecalciferol had higher mean concentration of 25-OHD compared to those who were not receiving it (p=0.027) and to the controls (p=0.047). In 23 children on vitamin D and calcium supplementation for an average 6-month time, we observed an increase in the mean BMD values (p=0.004), however, mean BMD z-score and 25-OHD concentrations did not significantly change over time.

CONCLUSIONS

Vitamin D and bone density deficits are remarkably common in steroid-treated children with glomerulopathies, despite vitamin D and calcium repletion. In order to enhance the effectiveness of vitamin D supplementation for improvement of bone density, we suggest regular assessment of serum concentration of 25-OHD that can guide subsequent dose adjustment of vitamin D.

Bone density and structure in long-term survivors of pediatric allogeneic hematopoietic stem cell transplantation

Children requiring allogeneic hematopoietic stem cell transplantation (alloHSCT) have multiple risk factors for impaired bone accrual. The impact of alloHSCT on volumetric bone mineral density (vBMD) and cortical structure has not been addressed. Tibia peripheral quantitative computed tomography (pQCT) scans were obtained in 55 alloHSCT recipients, ages 5 to 26 years, a median of 7 (range, 3-16) years after alloHSCT. pQCT outcomes were converted to sex- and race- specific Z-scores relative to age based on reference data in >700 concurrent healthy participants. Cortical section modulus (Zp; a summary measure of cortical bone structure and strength), and muscle and fat area Z-scores were further adjusted for tibia length for age Z-scores. AlloHSCT survivors had lower height Z-scores (-1.21 ± 1.25 versus 0.23 ± 0.92; p < 0.001), versus reference participants; BMI Z-scores did not differ. AlloHSCT survivors had lower trabecular vBMD (-1.05; 95% confidence interval [CI], -1.33 to -0.78; p < 0.001), cortical Zp (-0.63; 95% CI, -0.91 to -0.35; p < 0.001), and muscle (-1.01; 95% CI, -1.30 to -0.72; p < 0.001) Z-scores and greater fat (0.82; 95% CI, 0.54-1.11; p < 0.001) Z-scores, versus reference participants. Adjustment for muscle deficits eliminated Zp deficits in alloHSCT. Total body irradiation (TBI) was associated with lower trabecular vBMD (-1.30 ± 1.40 versus -0.49 ± 0.88; p = 0.01) and muscle (-1.34 ± 1.42 versus -0.34 ± 0.87; p < 0.01) Z-scores. Growth hormone deficiency (GHD) was associated with lower Zp Z-scores (-1.64 ± 2.47 versus -0.28 ± 1.24; p = 0.05); however, muscle differences were not significant (-1.69 ± 1.84 versus -0.78 ± 1.01; p = 0.09). History of graft versus host disease was not associated with pQCT outcomes. In summary, alloHSCT was associated with significant deficits in trabecular vBMD, cortical geometry, and muscle area years after transplantation. TBI and GHD were significant risk factors for musculoskeletal deficits. Future studies are needed to determine the metabolic and fracture implications of these deficits, and to identify therapies to improve bone accrual following alloHSCT during childhood.

MR enterography of extraluminal manifestations of inflammatory bowel disease in children and adolescents: moving beyond the bowel wall

OBJECTIVE

The purpose of this review is to describe the extraintestinal manifestations of inflammatory bowel disease at MR enterography of children and adolescents.

CONCLUSION

MR enterography excellently depicts a variety of extraluminal manifestations of inflammatory bowel disease affecting a variety of organ systems. Because many of these findings can be clinically important, it is critical that radiologists look beyond the bowel wall when interpreting these images.

Non-alcoholic fatty liver disease is associated with low bone mineral density in obese children

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. Liver disease can be a cause of low bone mineral density. Whether or not NAFLD influences bone health is not known.

AIM

To evaluate bone mineral density in obese children with and without NAFLD.

METHODS

Thirty-eight children with biopsy-proven NAFLD were matched for age, gender, race, ethnicity, height and weight to children without evidence of liver disease from the National Health and Nutrition Examination Survey. Bone mineral density was measured by dual energy X-ray absorptiometry. Age and gender-specific bone mineral density Z-scores were calculated and compared between children with and without NAFLD. After controlling for age, gender, race, ethnicity and total per cent body fat, the relationship between bone mineral density and the severity of histology was analysed in children with NAFLD.

RESULTS

Obese children with NAFLD had significantly (P < 0.0001) lower bone mineral density Z-scores (-1.98) than obese children without NAFLD (0.48). Forty-five per cent of children with NAFLD had low-bone mineral density for age, compared to none of the children without NAFLD (P < 0.0001). Among those children with NAFLD, children with NASH had a significantly (P < 0.05) lower bone mineral density Z-score (-2.37) than children with NAFLD who did not have NASH (-1.58).

CONCLUSIONS

The NAFLD was associated with poor bone health in obese children. More severe disease was associated with lower bone mineralisation. Further studies are needed to evaluate the underlying mechanisms and consequences of poor bone mineralisation in children with NAFLD.

Can bisphosphonates play a role in the treatment of children with chronic kidney disease?

In patients with chronic kidney disease (CKD) renal osteodystrophy, in the form of either low- or high-turnover bone disease, is quite common. While renal transplantation is expected to reverse renal osteodystrophy, long-term treatment with glucocorticoids before and/or after transplantation may lead to osteoporosis instead. Osteoporosis is defined as a skeletal disease with low bone mineral density, microarchitectural deterioration, and concomitant fragility. In adults, bisphosphonates are widely used to treat osteoporosis and other diseases associated with excessive bone resorption. In pediatric CKD patients the efficacy and safety of these drugs have not yet been addressed adequately and thus no evidence-based recommendations regarding the optimal type of bisphosphonate, dosage, or duration of therapy are available. Furthermore, while in adults the determination of areal bone mineral density is sufficient to diagnose osteoporosis, this is not the case in children. Instead, in pediatric patients, careful morphological assessment of bone structure and formation is required. Indeed, data from studies with uremic rats indicated that bisphosphonates, via a deceleration of bone turnover, have the potential not only to aggravate pre-existing adynamic bone disease, but also to impair longitudinal growth. Thus, the widespread use of bisphosphonates in children with CKD should be discouraged until the risks and benefits have been carefully elucidated in clinical trials.

Clinical features and treatment responses of children with eosinophilic gastroenteritis

BACKGROUND

Clinical features and treatment responses in pediatric patients with eosinophilic gastroenteritis are rarely reported. This study aimed to evaluate the clinical manifestations and outcome of eosinophilic gastroenteritis in children of Asian background.

METHODS

Between 1997 and 2009, 14 Taiwanese patients (nine boys and five girls), with median age of 8.3 years (range, 1.4-14.3 years), were diagnosed with eosinophilic gastroenteritis. The diagnosis was confirmed by the presence of gastrointestinal symptoms, peripheral eosinophilia, and a histology-proved biopsy. The clinical data and responses to medical treatment were analyzed.

RESULTS

Initial symptoms included abdominal pain (43%), anemia (36%), hypoalbuminemia (14%), recurrent vomiting (7%), bloody stool (7%), and growth failure (7%). Peripheral eosinophilia was present in 10 patients (71.4%) and positive stool occult blood in seven patients (50%). Endoscopic examination revealed ulcer disease in four patients (28.6%). The treatment included steroid alone, montelukast alone, steroid+montelukast, and steroid+montelukast+ketotifen. Among the patients treated with steroid, two (two of nine, 22%) had successfully tapered off steroid without recurring symptoms. Three patients (three of nine, 33%) had relapses after discontinuing steroid, three (three of nine, 33%) still required low-dose steroid, and one lost to follow-up. There was no relapse in the four patients treated with montelukast alone.

CONCLUSIONS

A high percentage of patients presented with gross or occult gastrointestinal bleeding with or without abdominal pain. Endoscopic biopsy is necessary for diagnosis. Steroid was the mainstay treatment for active diseases; montelukast was also effective for the disease or as a maintenance therapy in this study.

Skeletal health of children and adolescents with inflammatory bowel disease

Current evidence points to suboptimal bone health in children and adolescents with inflammatory bowel disease (IBD) when compared with their healthy peers. This compromise is evident from diagnosis. The clinical consequences and long-term outcome of this finding are still unknown. The mechanism of suboptimal bone health in children and adolescents with IBD lays mainly in reduced bone formation, but also reduced bone resorption, processes necessary for bone growth. Factors contributing to this derangement are inflammation, delayed growth and puberty, lean mass deficits, and use of glucocorticoids. We recognize that evidence is sparse on the topic of bone health in children and adolescents with IBD. In this clinical guideline, based on current evidence, we provide recommendations on screening and monitoring bone health in children and adolescents with IBD, including modalities to achieve this and their limitations; monitoring of parameters of growth, pubertal development, and reasons for concern; evaluation of vitamin D status and vitamin D and calcium intake; exercise; and nutritional support. We also report on the current evidence of the effect of biologics on bone health in children and adolescents with IBD, as well as the role of bone active medications such as bisphosphonates. Finally, we summarize the existing numerous gaps in knowledge and potential subjects for future research endeavors.

Congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) due to P450c21 (21-hydroxylase deficiency) is a common autosomal recessive disorder. This disorder is due to mutations in the CYP21A2 gene which is located at chromosome 6p21. The clinical features reflect the magnitude of the loss of function mutations. Individuals with complete loss of function mutations usually present in the neonatal period. The clinical features of individuals with mild loss of function mutations are predominantly due to androgen excess rather than adrenal insufficiency leading to an ascertainment bias favoring diagnosis in females. Treatment goals include normal linear growth velocity and "on-time" puberty in affected children. For adolescent and adult women, treatment goals include regularization of menses, prevention of progression of hirsutism, and fertility. This article will review key aspects regarding pathophysiology, diagnosis, and treatment of CAH.

Methotrexate toxicity in growing long bones of young rats: a model for studying cancer chemotherapy-induced bone growth defects in children

The advancement and intensive use of chemotherapy in treating childhood cancers has led to a growing population of young cancer survivors who face increased bone health risks. However, the underlying mechanisms for chemotherapy-induced skeletal defects remain largely unclear. Methotrexate (MTX), the most commonly used antimetabolite in paediatric cancer treatment, is known to cause bone growth defects in children undergoing chemotherapy. Animal studies not only have confirmed the clinical observations but also have increased our understanding of the mechanisms underlying chemotherapy-induced skeletal damage. These models revealed that high-dose MTX can cause growth plate dysfunction, damage osteoprogenitor cells, suppress bone formation, and increase bone resorption and marrow adipogenesis, resulting in overall bone loss. While recent rat studies have shown that antidote folinic acid can reduce MTX damage in the growth plate and bone, future studies should investigate potential adjuvant treatments to reduce chemotherapy-induced skeletal toxicities.