Bone marrow adiposity in pediatric Crohn's disease.

Patients with Crohn's disease often have low bone mineral density and an increased risk of osteoporosis. Although decreased bone formation can be seen at diagnosis, the underlying pathophysiology of suboptimal bone accrual remains poorly understood. We sought to evaluate a novel mechanism affecting osteogenesis in patients with Crohn's disease. In this case series, we evaluated bone marrow composition at the distal femur and proximal tibia of the left knee measured via magnetic resonance (MR) spectroscopy and relaxometry in five adolescents with the diagnosis of Crohn's disease. The subjects were enrolled prospectively between 2011 and 2013 at Boston Children's Hospital. Additional clinical information, including DXA scans to evaluate bone mineral density and body composition, and Crohn's disease history, such as glucocorticoid use and disease duration, were assessed. Healthy adolescents have persistent hematopoietic marrow with only 40 to 50 % fat in the long bone metaphyses. The current participants with Crohn's disease had increased marrow adiposity, with a mean fat fraction of 67.8 %. There appeared to be a trend towards higher fat fraction with shorter disease duration, while participants with the longest disease duration had the lowest fat fraction. Participants also had decreased bone density, increased fat mass, and lower lean mass, as assessed by DXA and compared to pediatric reference data. Our MRI results demonstrate increased marrow adiposity in children with Crohn's disease, especially early in the course of the disease. DXA may better demonstrate longer-term effects on bone. Additional studies are needed to evaluate bone marrow composition in these patients and to elucidate further the inverse relationship between marrow adipocytes and osteogenesis, as well as the relationship between bone marrow adiposity and body composition.

Risk factors for low bone mineral density in pediatric inflammatory bowel disease: the positive role of physical activity.

OBJECTIVE: In pediatric inflammatory bowel disease (IBD), the prevalence of low bone mineral density (BMD) and bone fractures and the relationship between these are still debated. Our aim was to report data from a cohort of pediatric patients with IBD. PATIENTS AND METHODS: Cross-sectional assessment of growth and BMD [(dual-energy x-ray absorptiometry (DXA)] and retrospective chart review were performed to report the lifetime prevalence of bone fractures and clinical associations with patients' data. RESULTS: We examined 216 patients with IBD, 8-25 years old (median: 14 years). Low BMD was found in 12.5% (spine) and 27% (total body). Multiple regression analysis showed that BMD was predicted by Z-scores for height and weight at DXA. History of menstrual irregularities and nasogastric tube feedings was associated with lower BMD, whereas physical activity and higher Z-score for height at DXA were associated with higher BMD.The prevalence of lifetime fractures was 11.8%. Patients with a history of fractures had lower Z-scores for spine BMD (-1.20 vs. -0.69, P=0.020) and total-body BMD (-1.30 vs. -0.75, P=0.014) compared with those without a history of fractures. Patients with spine BMD Z-score of up to -2 SD score had significantly increased prevalence of fractures compared with those with Z-score more than -2 SD score (28 vs. 10%, P=0.015). CONCLUSION: This study provides further insight into risk factors for low BMD in pediatric IBD. Novel findings were the association between low BMD and fractures, and the positive relationship between BMD and physical activity.

Maintenance of optimal vitamin D status in children and adolescents with inflammatory bowel disease: a randomized clinical trial comparing two regimens.

CONTEXT: Vitamin D promotes bone health and regulates the immune system, both important actions for pediatric patients with inflammatory bowel disease (IBD). The supplementation dose that would maintain optimal serum 25-hydroxyvitamin D concentration (25OHD ≥ 32 ng/mL) is unknown. OBJECTIVE: The objective of the study was to compare two supplementation regimens' efficacy and safety in maintaining optimal 25OHD in children with IBD. DESIGN: This was a randomized, not blinded, controlled trial. SETTING: The trial was conducted in the Boston Children's Hospital Clinical and Translational Study Unit. PARTICIPANTS: Sixty-three patients, aged 8-18 years with IBD and baseline 25OHD greater than 20 ng/mL were enrolled; 48 completed the study, and one withdrew for adverse events. INTERVENTION: Arm A received 400 IU of oral vitamin D2 daily (n = 32). Arm B received 1000 IU daily in the summer/fall and 2000 IU in the winter/spring (n = 31). MAIN OUTCOME: The main outcome was the probability of maintaining 25OHD of 32 ng/mL or greater in all trimonthly visits for 12 months. RESULTS: Three participants in arm A (9.4%) and three in arm B (9.7%) achieved the primary outcome (P = .97). The incidence of adverse events, all minor, did not differ. More participants in arm A developed C-reactive protein level of 1 mg/dL or greater (31% vs 10%, P = .04) and IL-6 greater than 3 pg/mL (54% vs 27%, P = .05). CONCLUSIONS: Daily oral vitamin D2 doses up to 2000 IU were inadequate to maintain optimal 25OHD but were well tolerated. The finding of lower incidence of elevated inflammatory markers and cytokines among participants receiving higher vitamin D2 doses merits further study.

Treatment of vitamin D insufficiency in children and adolescents with inflammatory bowel disease: a randomized clinical trial comparing three regimens.

CONTEXT: Vitamin D insufficiency [serum 25-hydroxyvitamin D (25OHD) concentration less than 20 ng/ml] is prevalent among children with inflammatory bowel disease (IBD), and its treatment has not been studied. OBJECTIVE: The aim of this study was to compare the efficacy and safety of three vitamin D repletion regimens. DESIGN AND SETTING: We conducted a randomized, controlled clinical trial from November 2007 to June 2010 at the Clinical and Translational Study Unit of Children's Hospital Boston. The study was not blinded to participants and investigators. PATIENTS: Eligibility criteria included diagnosis of IBD, age 5-21, and serum 25OHD concentration below 20 ng/ml. Seventy-one patients enrolled, 61 completed the trial, and two withdrew due to adverse events. INTERVENTION: Patients received orally for 6 wk: vitamin D(2), 2,000 IU daily (arm A, control); vitamin D(3), 2,000 IU daily (arm B); vitamin D(2), 50,000 IU weekly (arm C); and an age-appropriate calcium supplement. MAIN OUTCOME MEASURE: We measured the change in serum 25OHD concentration (Δ25OHD) (ng/ml). Secondary outcomes included change in serum intact PTH concentration (ΔPTH) (pg/ml) and the adverse event occurrence rate. RESULTS: After 6 wk, Δ25OHD ± se was: 9.3 ± 1.8 (arm A); 16.4 ± 2.0 (arm B); 25.4 ± 2.5 (arm C); P (A vs. C) = 0.0004; P (A vs. B) = 0.03. ΔPTH ± SE was -5.6 ± 5.5 (arm A); -0.1 ± 4.2 (arm B); -4.4 ± 3.9 (arm C); P = 0.57. No participant experienced hypercalcemia or hyperphosphatemia, and the prevalence of hypercalciuria did not differ among arms at follow-up. CONCLUSIONS: Oral doses of 2,000 IU vitamin D(3) daily and 50,000 IU vitamin D(2) weekly for 6 wk are superior to 2,000 IU vitamin D(2) daily for 6 wk in raising serum 25OHD concentration and are well-tolerated among children and adolescents with IBD. The change in serum PTH concentration did not differ among arms.

Prevalence and risk factors for hypovitaminosis D in young patients with inflammatory bowel disease.

Vitamin D plays an important role in bone homeostasis. We aimed to report the prevalence of hypovitaminosis D in children with inflammatory bowel disease (IBD) and risk factors associated with low serum 25-hydroxyvitamin D (25OHD) concentration in children with IBD. Risk factors for deficiency of this vitamin are similar to those in healthy children, with the addition of higher erythrocyte sedimentation rate. Both patients with ulcerative colitis and Crohn disease are at risk for hypovitaminosis D.

Efficacy and harms of nasal calcitonin in improving bone density in young patients with inflammatory bowel disease: a randomized, placebo-controlled, double-blind trial.

OBJECTIVES: There are very few published studies of agents having the potential to improve bone health in children with inflammatory bowel disease (IBD). The objective of this study was to establish the efficacy and safety of intranasal calcitonin in improving bone mineral density (BMD) in young patients with IBD and to define additional factors that impact bone mineral accrual. METHODS: We conducted a randomized, placebo-controlled, double-blind clinical trial in 63 participants, ages 8-21 years, with a spinal BMD Z-score ≤ -1.0 s.d. measured by dual energy X-ray absorptiometry. Subjects were randomized to 200 IU intranasal calcitonin (n=31) or placebo (n=32) daily. All received age-appropriate calcium and vitamin D supplementation. Subsequent BMD measurements were obtained at 9 and 18 months. RESULTS: Intranasal calcitonin was well tolerated. Adverse event frequency was similar in both treatment groups, and such events were primarily minor, reversible, and limited to the upper respiratory tract. The BMD Z-score change documented at screening and 9 months and screening and 18 months did not differ between the two therapeutic arms. In participants with Crohn's disease, the spinal BMD Z-score improved between screening and 9 months (change in spine BMD Z-score (ΔZSBMD)(9-0)) in the calcitonin group (ΔZSBMD(9-0)(calcitonin)=0.21 (0.37), ΔZSBMD(9-0)(placebo)=-0.15 (0.5), P=0.02); however, this was only a secondary subgroup analysis. Bone mineral accrual rate during the trial did not lead to normalization of BMD Z-score in this cohort. Factors favoring higher bone mineral accrual rate were lower baseline BMD and higher baseline body mass index Z-score, improvement in height Z-score, higher serum albumin, hematocrit and iron concentration, and more hours of weekly weight-bearing activity. Factors associated with lower bone mineral accrual rate were more severe disease-as indicated by elevated inflammatory markers, need for surgery, hospitalization, and the use of immunomodulators-and higher daily caffeine intake. CONCLUSIONS: Intranasal calcitonin is well tolerated but does not offer a long-term advantage in youth with IBD and decreased BMD. Bone mineral accrual rate remains compromised in youth with IBD and low BMD raising concerns for long-term bone health outcomes. Improvement in nutritional status, catch-up linear growth, control of inflammation, increase in weight-bearing activity, and lower daily caffeine intake may be helpful in restoring bone density in children with IBD and low BMD.

Vitamin D status in gastrointestinal and liver disease.

PURPOSE OF REVIEW: The purpose of this review is to report on the vitamin D status and its relationship with bone health in individuals with gastrointestinal and liver disorders. In addition, recommendations regarding replacement and maintenance of optimal vitamin D stores, as well as the state of knowledge regarding its effect on the disease through its actions on the immune system, will be reviewed. RECENT FINDINGS: The scientific community has revised upward the serum levels of vitamin D considered optimal, and doses of vitamin D much larger than those currently recommended may be needed to maintain these levels, especially in individuals with gastrointestinal and liver disorders. The relationship between vitamin D and bone health in this population is controversial. The role of vitamin D in the regulation of the immune system continues to be elucidated. SUMMARY: Hypovitaminosis D is prevalent among individuals with gastrointestinal and liver disease. Although replacement and supplementation guidelines have not been well defined, practitioners should aim for a serum 25-hydroxyvitamin D level of at least 32 ng/ml. The contribution of vitamin D to the bone health of these individuals and its role in altering disease course through its actions on the immune system remain to be elucidated.

Report on the vitamin D status of adult and pediatric patients with inflammatory bowel disease and its significance for bone health and disease.

Vitamin D is a hormone responsible for calcium homeostasis and essential for bone mineralization throughout the lifespan. Recent studies revealed a high prevalence of hypovitaminosis D among healthy adults and children, especially in the northern hemisphere, and a link between this condition and suboptimal bone health. Moreover, maintenance of what are today considered optimal vitamin D stores has not been achieved throughout the year with currently recommended daily intake for vitamin D. The prevalence of hypovitaminosis D is even higher among adults with inflammatory bowel disease (IBD), a situation that may be caused by malabsorption and gastrointestinal losses through an inflamed intestine, among other factors. In children with IBD, existing reports of vitamin D status are scarce. The relationship between vitamin D status and bone health, although well-established in healthy adults and children, has been controversial among adults and children with IBD, and the reasons for this have not been investigated to date. Studies in animal models of colitis and in vitro human studies support a role of vitamin D in the regulation of the immune system of the gut and the potential of vitamin D and its derivatives as therapeutic adjuncts in the treatment of IBD. This role of vitamin D has not been investigated with translational studies to date. Currently, there are no guidelines for monitoring vitamin D status, treating hypovitaminosis D, and maintaining optimal vitamin D stores in patients with IBD. These tasks may prove particularly difficult because of malabsorption and gastrointestinal losses that are associated with IBD.

Vitamin D status in children and young adults with inflammatory bowel disease.

OBJECTIVES: Previous studies of vitamin D status in pediatric patients with inflammatory bowel disease have revealed conflicting results. We sought to report (1) the prevalence of vitamin D deficiency (serum 25-hydroxy-vitamin D concentration < or = 15 ng/mL) in a large population with inflammatory bowel disease, (2) factors predisposing to this problem, and (3) its relationship to bone health and serum parathyroid hormone concentration. PATIENTS AND METHODS: A total of 130 patients (8-22 years of age) with inflammatory bowel disease, 94 with Crohn disease and 36 with ulcerative colitis, had serum 25-hydroxy-vitamin D, intact parathyroid hormone, and lumbar spine bone mineral density (using dual-energy x-ray absorptiometry) measured at Children's Hospital Boston. RESULTS: The prevalence of vitamin D deficiency was 34.6%. Mean serum 25-hydroxy-vitamin D concentration was similar in patients with Crohn disease and ulcerative colitis, 52.6% lower among patients with dark skin complexion, 33.4% lower during the winter months (December 22 to March 21), and 31.5% higher among patients who were taking vitamin D supplements. Serum 25-hydroxy-vitamin D concentration was positively correlated with weight and BMI z score, disease duration, and serum albumin concentration and negatively correlated with erythrocyte sedimentation rate. Patients with Crohn disease and upper gastrointestinal tract involvement were more likely to be vitamin D deficient than those without it. Serum 25-hydroxy-vitamin concentration was not associated with lumbar spine bone mineral density z score or serum parathyroid hormone concentration. CONCLUSIONS: Vitamin D deficiency is highly prevalent among pediatric patients with inflammatory bowel disease. Factors predisposing to the problem include having a dark-skin complexion, winter season, lack of vitamin D supplementation, early stage of disease, more severe disease, and upper gastrointestinal tract involvement in patients with Crohn disease. The long-term significance of hypovitaminosis D for this population is unknown at present and merits additional study.

Pediatric inflammatory bowel disease.

PURPOSE OF THIS REVIEW: The prevalence of early-onset inflammatory bowel disease has been on the rise, with children and adolescents currently accounting for approximately 30% of all patients with this condition. Remarkable new advances in diagnostic modalities and therapy for adults with inflammatory bowel disease, and further information about the role of genetics in determining susceptibility to disease make the review of the recent literature in pediatric inflammatory bowel disease more timely than ever. RECENT FINDINGS: In the area of genetics, new studies provide strong evidence for genetic susceptibility to disease, and match genotype with phenotypic presentation. A few studies examine the use of noninvasive diagnostic modalities, such as MRI, and biomarkers (fecal lactoferrin) in pediatric inflammatory bowel disease. Remarkable new agents in therapy for adults with inflammatory bowel disease have been empirically administered to children with inflammatory bowel disease. The first attempts to systematically study the effects of these agents in children and adolescents are reviewed here. Furthermore, new studies revise our notion of surgical outcomes in pediatric inflammatory bowel disease. SUMMARY: Although premature for clinical practice application, the role of genetic testing in determining disease susceptibility and assisting with prognosis and course of therapy is clearly evolving and needs further study. As new therapeutic agents join the available treatments of inflammatory bowel disease it is imperative to include pediatric patients in clinical trials. The goals of future studies will be to alter the natural history of early-onset inflammatory bowel disease, reduce the frequency of recurrences, and perhaps reduce requirements for surgical intervention.