Pediatric inflammatory bowel disease and bone health

Use of exclusive enteral nutrition is just as effective as corticosteroids in newly diagnosed pediatric Crohn's disease

BACKGROUND

The efficacy of exclusive enteral nutrition (EEN) in induction of remission in pediatric Crohn's disease (CD) is reported to be equivalent to that of corticosteroids (CS).

AIMS

Our objective was to compare the efficacy of EEN and CS in inducing remission in pediatric onset CD and the effects of the treatment on nutritional status and bone mineral density (BMD).

METHODS

Medical charts were retrospectively studied for patients diagnosed with CD between 2000 and 2010 at the Stollery children's hospital in Edmonton, Alberta. Anthropometric and dual-energy X-ray absorptiometry (DXA) data were collected to assess effects of therapy; clinical remission, relapse, and severity were defined on the basis of the pediatric Crohn's disease activity index.

RESULTS

To induce remission at first presentation, 36 patients (mean age 12.9 years) received EEN and 69 (mean age 11.2 years) received CS. Remission (88.9% in the EEN group versus 91.3% in the CS group (p=0.73) at 3 months) and relapse (40.6 vs. 28.6%, respectively (p=0.12) over 12 months) were similar in both treatment groups. Thirty-four patients had paired DXA scans at the time of diagnosis and one year later: 16 given EEN and 18 given CS. Change in BMD spine z-scores based on bone age adjusted for height and chronological age was greater for EEN patients but not statistically significant (Δz-score 0.30 vs. 0.03, p=0.28).

CONCLUSIONS

EEN has similar efficacy to corticosteroids; however, EEN may lead to better BMD accrual. EEN should be preferred to corticosteroids as first-line therapy for induction of remission in pediatric CD.

Glucocorticoids in pediatric inflammatory bowel disease

Children with moderate to severe inflammatory bowel disease (IBD) are treated with systemic glucocorticoids (GCs). The majority of the patients respond to the given treatment; however, steroid resistance and dependency are significant clinical problems. Also therapy-related side effects limit the use of GCs in the control of active inflammation. This review summarizes recent knowledge of GC treatment in pediatric patients with IBD.

Gut-bone interactions and implications for the child with chronic gastrointestinal disease

Bone is not simply a framework on which to hang viscera and connective tissue; it is also a dynamic interactive organ system with roles in immunoregulation, adipogenesis, and vascular calcification, among others. Bone is intimately affected by chronic disease, including gastrointestinal disease. The mechanisms for bone loss in conditions such as inflammatory bowel disease, celiac disease, and cystic fibrosis are discussed with regard to the role of the inflammatory response. Furthermore, we raise the issue of effects of inflammation on both intestinal and renal calcium and phosphate transport, although the ways in which these actions affect bone are not explained and require further research. The stress response, a prominent feature following burn injury, is also elucidated and its relation to gastrointestinal disease is examined. We then discuss the importance of knowing the mechanism of bone loss to determine proper prevention and treatment for the bone loss in specific gastrointestinal conditions.

Vitamin D status and supplementation in pediatric gastrointestinal disease

PURPOSE

To evaluate vitamin D status and supplementation in the pediatric population with common gastrointestinal diseases. The literature was searched for studies on vitamin D status in children with inflammatory bowel disease (IBD), celiac disease, and liver disease. Vitamin D supplementation in healthy children was also reviewed.

CONCLUSIONS

Those with gastrointestinal diseases are more likely to have vitamin D deficiency as a result of malabsorption. Current recommendations for supplementation may be too low to achieve optimal levels.

PRACTICE IMPLICATIONS

It is important to monitor vitamin D levels in pediatric populations with gastrointestinal diseases and appropriately treat levels that are insufficient.

Advances in the understanding of mineral and bone metabolism in inflammatory bowel diseases

Chronic inflammatory disorders such as inflammatory bowel diseases (IBDs) affect bone metabolism and are frequently associated with the presence of osteopenia, osteoporosis, and increased risk of fractures. Although several mechanisms may contribute to skeletal abnormalities in IBD patients, inflammation and inflammatory mediators such as TNF, IL-1β, and IL-6 may be the most critical. It is not clear whether the changes in bone metabolism leading to decreased mineral density are the result of decreased bone formation, increased bone resorption, or both, with varying results reported in experimental models of IBD and in pediatric and adult IBD patients. New data, including our own, challenge the conventional views, and contributes to the unraveling of an increasingly complex network of interactions leading to the inflammation-associated bone loss. Since nutritional interventions (dietary calcium and vitamin D supplementation) are of limited efficacy in IBD patients, understanding the pathophysiology of osteopenia and osteoporosis in Crohn's disease and ulcerative colitis is critical for the correct choice of available treatments or the development of new targeted therapies. In this review, we discuss current concepts explaining the effects of inflammation, inflammatory mediators and their signaling effectors on calcium and phosphate homeostasis, osteoblast and osteoclast function, and the potential limitations of vitamin D used as an immunomodulator and anabolic hormone in IBD.