Celiac disease in children: impact on bone health

Osteoporosis and Bone Fragility in Children: Diagnostic and Treatment Strategies

The incidence of osteoporosis in children is increasing because of the increased survival rate of children with chronic diseases and the increased use of bone-damaging drugs. As childhood bone fragility has several etiologies, its management requires a thorough evaluation of all potentially contributing pathogenetic mechanisms. This review focuses on the main causes of primary and secondary osteoporosis and on the benefits and limits of the different radiological methods currently used in clinical practice for the study of bone quality. The therapeutic and preventive strategies currently available and the most novel diagnostic and treatment strategies are also presented. Optimal management of underlying systemic conditions is key for the treatment of bone fragility in childhood. DXA still represents the gold standard for the radiologic evaluation of bone health in children, although other imaging techniques such as computed tomography and ultrasound evaluations, as well as REMS, are increasingly studied and used. Bisphosphonate therapy is the gold standard for pharmacological treatment in both primary and secondary pediatric osteoporosis. Evidence and experience are building up relative to the use of monoclonal antibodies such as denosumab in cases of poor response to bisphosphonates in specific conditions such as osteogenesis imperfecta, juvenile Paget's disease and in some cases of secondary osteoporosis. Lifestyle interventions including adequate nutrition with adequate calcium and vitamin D intake, as well as physical activity, are recommended for prevention.

No major reduction in bone mineral density after long-term treatment of patients with Celiac Disease

BACKGROUND

At time of diagnosis, patients with celiac disease (CD) have been shown to have lower bone mineral density (BMD) than healthy controls. It is unclear whether adult patients with CD can regain a normal BMD after treatment with a gluten-free diet (GFD).

METHODS

Patients diagnosed with CD as adults, who had been treated with GFD for a minimum of two years, were examined by dual energy X-ray absorptiometry (DXA) to determine BMD at femoral neck and spine L2-4. Adherence to GFD was measured using the Celiac Disease Adherence Test (CDAT) scoring tool.

RESULTS

143 CD patients underwent DXA assessment, mean age was 55.8 years and mean treatment duration was 9.3 years. 67% of the patients were women, and 51% of these were postmenopausal. The prevalence of low bone mass (Z-score ≤ -1.0) was 18.2% (95%CI: 12.7-25.3%) at femoral neck and 23.1% (95%CI: 16.9-30.6%) at spine L2-4. An increase in low bone density prevalence at spine L2-4 compared to the expected prevalence (p = 0.016) was limited to the postmenopausal women. In a multiple regression analysis, only postmenopausal status and poor adherence to GFD was independently associated with reduced bone density, this however limited to spine L2-4.

CONCLUSION

Our study shows a small increase in the prevalence of low bone density at lumbar spine limited to the postmenopausal women. The main finding is that the majority of the CD patients after two years of treatment with GFD had a normal bone density when adjusted for age, gender, ethnicity and weight.

Score-based diagnostic approach to celiac disease and bone mineral density

BACKGROUND

The aim of this study was to assess the performance of a score-based diagnostic approach (SBDA) proposed in the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) 2012 guideline, and the usefulness of bone mineral density (BMD) measurement in SBDA as an objective finding in the diagnosis of celiac disease (CD).

METHODS

The SBDA scores of 153 biopsy-proven celiac diagnosed children (derived from symptomatology, serology, human leukocyte antigen [HLA] analysis, histology) were calculated. Additionally, BMD Z scores obtained at diagnosis were also investigated. The diagnostic sensitivity of SBDA was tested in different scenarios in which low BMD was scored as a diagnostic finding.

RESULTS

The mean age of children was 9.48 ± 3.59 years and 54.2% were female. All patients scored ≥4, which is the minimum score to diagnose CD in SBDA. Mean BMD Z score in 142 of 153 patients was -2.70 ± 1.16, and 73.9% of them were below -2. Moreover, different diagnostic scenarios without histology were tested. In one of them, BMD and HLA were not included and the sensitivity was 85.2%. In another one, low BMD was scored as an equivalent of malabsorption, HLA was not included and sensitivity was 97.2%. The sensitivities of these scenarios were significantly different (P = 0.001).

CONCLUSION

In the absence of both HLA and histology, accepting low BMD as an equivalent of malabsorption drastically increased the diagnostic sensitivity, while SBDA had limited success. Therefore, BMD might be useful when HLA and biopsy are not available.

Prevalence of and Risk Factors for Low Bone Mineral Density in Children With Celiac Disease

BACKGROUND & AIMS

Celiac disease can reduce bone mineral density. We sought to determine the prevalence and risk factors for low areal bone mineral density (aBMD) in children with celiac disease.

METHODS

We performed a retrospective cohort study of 673 children with celiac disease (63% female; median age at diagnosis, 10.6 y; interquartile range, 7.8-13.9) who underwent dual x-ray absorptiometry (DXA) from 2009 through 2016 at the Children's Hospital of Philadelphia. We collected demographic, clinical, and laboratory data from medical records. We performed logistic regression analysis to identify factors associated with low (Z less than -2) lumbar spine aBMD Z (aBMD-Z) scores at initial and subsequent tests.

RESULTS

The time between diagnosis of celiac disease and first DXA was 0 days (interquartile range, -11 to 31 d). The mean aBMD-Z score at the children's initial scan was -0.4 ± 1.2; 46 children had aBMD-Z scores less than -2 (6.8%; 95% CI, 5.2%-9.0%). Those who had a second DXA analysis (n = 108; 16.0%) had a significant increase in aBMD-Z score (mean change, 0.29; P = .0005). Higher body mass index (BMI) was associated with lower odds of a low aBMD-Z score at the initial DXA analysis (odds ratio, 0.46, 95% CI, 0.35-0.50). BMI-Z scores greater than -0.4 identified children with a low aBMD-Z at their initial DXA analysis with a 95% negative predictive value.

CONCLUSIONS

Approximately 7% of subjects with celiac disease had a low aBMD-Z score, determined by DXA, at the time of diagnosis; this value was nearly 3-fold higher than expected from a population of children of this age and sex distribution. BMI-Z scores could be used to identify children with celiac disease at risk for low BMD who should receive DXA screening.

Daily oligofructose-enriched inulin intake impacts bone turnover markers but not the cytokine profile in pediatric patients with celiac disease on a gluten-free diet: Results of a randomised, placebo-controlled pilot study

BACKGROUND

Bone metabolism disturbances are commonly observed in patients with newly diagnosed celiac disease (CD). The only available treatment for CD-the intake of a gluten-free diet (GFD)-has been found to be insufficient in effectively improving bone health in some patients. Therefore, there is an urgent need to modify the GFD so as to allow for the provision of all the necessary nutrients and improved absorption. Prebiotics intake reportedly improves the absorption of bone-related vitamin D and calcium as well as bone metabolism. The effect of prebiotic intake on bone health in CD patients has not been studied yet. This study aimed to evaluate the effect of oligofructose-enriched inulin intake on bone metabolism and immune response in children with CD on a GFD.

METHODS

A total of 34 children with CD were randomised into two groups receiving 10 g of oligofructose-enriched inulin (Synergy 1) or a placebo (maltodextrin) for three months, together with a strict GFD. The children's bone metabolism marker levels and cytokine profiles were analysed before and after the intervention.

RESULTS

After supplementation, the concentration of osteocalcin increased significantly in children receiving Synergy 1, while the concentration of bone alkaline phosphatase increased in both groups, independent of supplementation. After the intervention, the level of pyridinoline increased significantly in the placebo group, resulting in a concentration that was two times higher than that in the Synergy 1 group, in which it remained stable. Moreover, the plasma concentrations of N-terminal telopeptides of type I collagen decreased in both the groups, whereas the tartrate-resistant acid phosphatase 5b level increased particularly in the Synergy 1 group. The intervention did not lead to immunological response changes.

CONCLUSIONS

The proposed supplementation beneficially altered bone metabolism, through increased bone formation rates and decreased bone resorption process rates. Supplementation of GFD with prebiotic oligofructose-enriched inulin may be a promising auxiliary therapy for bone metabolism improvements in children with CD.

Bone mineral density and vitamin K status in children with celiac disease: Is there a relation?

BACKGROUND/AIMS

To investigate bone mineral density (BMD) in children with celiac disease (CD) and to evaluate the association between vitamin K levels and osteoporosis.

MATERIALS AND METHODS

Children with CD and age- and sex-matched healthy control subjects were prospectively included in the study. BMD was measured, and serum anti-tissue transglutaminase IgA, ferritin, folate, vitamin B12, 25-hydroxy vitamin D and K2, calcium, phosphate, alkaline phosphatase, and parathormone were assayed in all subjects.

RESULTS

Overall, 72 patients (mean age 11.69±3 years, 59.7% female) and 30 healthy subjects (mean age 12.27±2.12 years, 63.3% female) were enrolled. The mean BMD Z score of the celiac group was significantly lower than that of the control group (-1.23±1.07 vs. -0.35±1.04, p=0.001). Vitamin D and K2 values did not differ significantly between the two groups (p > 0.05). BMD was positively correlated with vitamin D (r=0.198, p=0.001) and negatively with PTH (r=-0.397, p=0.002).

CONCLUSION

The BMD of celiac patients was lower than that of the control subjects. There was no difference in terms of vitamin D and K2 levels between the two groups. Further studies investigating the level and effect of vitamin K on bone in CD are needed.

Extra-Intestinal Manifestation of Celiac Disease in Children

The aim of this literature review is to discuss the extra-intestinal manifestations of celiac disease within the pediatric celiac population.

Reduced Bone Mineral Density in Children With Screening-detected Celiac Disease

OBJECTIVES

The aim of the study was to assess whether bone mass and metabolism are impaired in genetically at-risk children with screening-detected celiac disease.

METHODS

Included were 71 children with screening-detected celiac disease diagnosed at 10.0 ± 0.7 (mean ± standard deviation) years and 142 matched controls and 30 children with screening-detected celiac disease diagnosed at 3.3 ± 0.4 years of age presently on a gluten-free diet for 6.9 ± 1.1 years and 60 matched controls. All participants were assessed for bone mineral density (BMD) of total body and spine by dual x-ray absorptiometry, serum 25(OH) vitamin D3, parathyroid hormone (PTH), interleukin (IL)-1β, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-15, interferon gamma, and tumor necrosis factor alpha.

RESULTS

At diagnosis, screening-detected celiac disease children as compared to controls had a mean -0.03 g/cm reduced BMD of both total body and spine (P = 0.009 and P = 0.005, respectively), a mean -11.4 nmol/L lower level of 25(OH) vitamin D3 (P < 0.001), and a mean +1.0 pmol/L higher PTH level (P < 0.001). Systemic levels of the cytokines IL-1β, IL-6, IL-8, IL-10, IL-12p70, IL-13, and tumor necrosis factor alpha were all increased in screening-detected celiac disease as compared to controls (P < 0.001). No difference in BMD, 25(OH) vitamin D3, PTH, and cytokine levels were detected in children on a gluten-free diet compared with controls.

CONCLUSIONS

Children with screening-detected celiac disease have reduced BMD, lower levels of vitamin D3, higher levels of PTH, and signs of systemic inflammation compared with controls. These differences were not found in celiac disease children on a gluten-free diet, indicating that children with screening-detected celiac disease benefit from an early diagnosis and treatment.

Evidence-Informed Expert Recommendations for the Management of Celiac Disease in Children

Although the need for effective long-term follow-up for patients with celiac disease (CD) has been recognized by many expert groups, published practice guidelines have not provided a clear approach for the optimal management of these patients. In an attempt to provide a thoughtful and practical approach for managing these patients, a group of experts in pediatric CD performed a critical review of the available literature in 6 categories associated with CD to develop a set of best practices by using evidence-based data and expert opinion. The 6 categories included the following: bone health, hematologic issues, endocrine problems, liver disease, nutritional issues, and testing. Evidence was assessed by using standardized criteria for evaluating the quality of the data, grade of evidence, and strength of conclusions. Over 600 publications were reviewed, and 172 were chosen for inclusion. The thorough review of the results demonstrated that the quality of the data available was often insufficient to provide unequivocal best practices. However, using the available data and the clinical experience of the panel, a practical framework for the management of children with CD was created. These recommendations were developed by our expert panel and do not necessarily reflect the policy of the American Academy of Pediatrics. The potential usefulness of these best practices is underscored by the fact that consensus, measured by the outcome of anonymous voting, was reached by the panel for 24 of the 25 questions. We hope that these best practices may be useful to the pediatric gastroenterology and larger general pediatric communities.

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.

The clinical significance of 25OH-Vitamin D status in celiac disease

Reduced bone mineral density is frequently found especially in adult celiac disease (CD) and dietary guidelines favor vitamin D supplementation in adults and children with CD. Vitamin D serum levels were investigated in CD populations in order to challenge its routine supplementation. Israeli (61), Spanish (59), CD children (groups 1 and 5, respectively) were compared to children with nonspecific abdominal pain (56), their parents (84) and Spanish adult CD patients (22) (group 2, 3, 4, respectively). 25(OH)-vitamin D was checked by LIAISON chemiluminescent immunoassays. Groups 5 and 1 had the highest levels compared to groups 4 and 3 with the lowest levels. The levels in groups 1 and 2 were comparable. Concerning 25(OH)-vitamin D sera levels, only the difference between group 5 and 4 was statistically significant (30.3 ± 12.3 and 20.2 ± 10.5 ng/ml, respectively p=0.003). When vitamin D was splitted above and below 20 ng/ml level, 54.5% of Spanish adult CD had vitamin D deficiency compared to 16.9% of the local CD children (p=0.001). 29.6% of group 2 had deficient levels compared to their parents with 50% (p=0.019). In conclusion, Vitamin D sera levels negatively correlate with age. Thus, mainly adult CD population should be assessed for vitamin D levels and supplemented accordingly.

Celiac disease in children and adolescents: special considerations

Although there are many commonalities between adult and pediatric celiac disease (CD), special considerations must be taken into account when working with children and adolescents. In this patient population, there are unique aspects of the epidemiology, pathogenesis, presentation, diagnosis, and management of CD. In terms of management, early and timely recognition of CD can maximize childhood and adolescent development and prevent complications. This requires insight into the unique presentations of CD in the pediatric population. Furthermore, health care providers must use proper screening methods and continue surveillance of at-risk individuals throughout childhood. Potential interventions for primary prevention of CD in children, although not completely understood, may offer some benefit. The goals of this article are to discuss in detail these special considerations when dealing with pediatric CD.

Bone health in children with celiac disease assessed by dual x-ray absorptiometry: effect of gluten-free diet and predictive value of serum biochemical indices

OBJECTIVES

In the present study, we aimed to assess bone status and the effect of gluten-free diet (GFD) in children with celiac disease (CD), and to evaluate the predictive value of standard serum biochemical indices in the diagnosis of bone mineral density (BMD) disturbances.

METHODS

Forty-five children at the time of diagnosis of CD (group A, 77.8% girls) and 36 children receiving GFD for >2 years (group B, 75% girls) were included. Sixteen children in group A were reexamined 12 months after initiation of GFD. Serum measurements of biochemical bone health indices and BMD, assessed by dual x-ray absorptiometry, were obtained.

RESULTS

Patients after 1 year of receiving GFD had higher BMD z scores compared with baseline (-1.45 ± 0.28 vs -0.61 ± 0.25, respectively, P = 0.004). BMD z scores were significantly lower than expected for the normal population, after 1 (P = 0.03) or at least 2 (P < 0.001) years of receiving GFD. In group B, BMD z score was positively correlated with 25-hydroxy vitamin D levels (P = 0.009). In the repeated measurements group, 25-hydroxy vitamin D differed between pre- and post-GFD (P = 0.018). No biochemical index was capable of predicting an abnormal BMD z score (receiver operating characteristic curve analysis, all of the areas under the curve <0.66).

CONCLUSIONS

GFD has a beneficial effect on bone health. Two years receiving diet do not ensure normalization. Biochemical markers are not indicative of BMD disturbances. Dual x-ray absorptiometry should be included in the standard management of children with CD.

Bone mineralization in celiac disease

Evidence indicates a well-established relationship between low bone mineral density (BMD) and celiac disease (CD), but data on the pathogenesis of bone derangement in this setting are still inconclusive. In patients with symptomatic CD, low BMD appears to be directly related to the intestinal malabsorption. Adherence to a strict gluten-free diet (GFD) will reverse the histological changes in the intestine and also the biochemical evidence of calcium malabsorption, resulting in rapid increase of BMD. Nevertheless, GFD improves BMD but does not normalize it in all patients, even after the recovery of intestinal mucosa. Other mechanisms of bone injury than calcium and vitamin D malabsorption are thought to be involved, such as proinflammatory cytokines, parathyroid function abnormalities, and misbalanced bone remodeling factors, most of all represented by the receptor activator of nuclear factor B/receptor activator of nuclear factor B-ligand/osteoprotegerin system. By means of dual-energy X-ray absorptiometry (DXA), it is now rapid and easy to obtain semiquantitative values of BMD. However, the question is still open about who and when submit to DXA evaluation in CD, in order to estimate risk of fractures. Furthermore, additional information on the role of nutritional supplements and alternative therapies is needed.

New clues in celiac disease epidemiology, pathogenesis, clinical manifestations, and treatment

Celiac disease (CD) is an immune-mediated enteropathy triggered by the ingestion of gluten in genetically susceptible individuals. It is one of the most common lifelong disorders on a worldwide basis. Celiac enteropathy is the final consequence of an abnormal immune reaction, showing features of both an innate and an adaptive response to gluten prolamins. The clinical spectrum is wide, including cases with either typical intestinal or atypical extraintestinal features, and silent forms. The only available treatment consists in dietary exclusion of grains containing gluten. New pharmacological treatment are currently under scrutiny.

Identifying patterns of immune-related disease: use in disease prevention and management

BACKGROUND

Childhood susceptibility to diseases linked with immune dysfunction affects over a quarter of the pediatric population in some countries. While this alone is a significant health issue, the actual impact of immune-related diseases extends over a lifetime and involves additional secondary conditions. Some comorbidities are well known (e.g., allergic rhinitis and asthma). However, no systematic approach has been used to identify life-long patterns of immune-based disease where the primary condition arises in childhood. Such information is useful for both disease prevention and treatment approaches.

DATA SOURCES

Recent primary research papers as well as review articles were obtained from PubMed, Chem Abstracts, Biosis and from the personal files of the authors. Search words used were: the diseases and conditions shown Figs. 1 and 2 in conjunction with comorbid, comorbidities, pediatric, childhood, adult, immune, immune dysfunction, allergy, autoimmune, inflammatory, infectious, health risks, environment, risk factors.

RESULTS

Childhood diseases such as asthma, type-1 diabetes, inflammatory bowel disease, respiratory infections /rhinitis, recurrent otitis media, pediatric celiac, juvenile arthritis and Kawasaki disease are examples of significant childhood health problems where immune dysfunction plays a significant role. Each of these pediatric diseases is associated with increased risk of several secondary conditions, many of which appear only later in life. To illustrate, four prototypes of immune-related disease patterns (i.e., allergy, autoimmunity, inflammation and infectious disease) are shown as tools for: 1) enhanced disease prevention; 2) improved management of immune-based pediatric diseases; and 3) better recognition of underlying pediatric immune dysfunction.

CONCLUSIONS

Identification of immune-related disease patterns beginning in childhood provides the framework for examining the underlying immune dysfunctions that can contribute to additional diseases in later life. Many pediatric diseases associated with dysfunctional immune responses have been linked with an elevated risk of other diseases or conditions as the child ages. Diseases within a pattern may be interlinked based on underlying immune dysfunctions and/or current therapeutic approaches for managing the entryway diseases. It may be beneficial to consider treatment options for the earliest presenting diseases that will concomitantly reduce the risk of immune-linked secondary conditions. Additionally, improved disease prevention is possible with more relevant and age-specific immune safety testing.

Metabolic osteopathy in celiac disease: importance of a gluten-free diet

Reduced bone mineral density (BMD) is frequently found in individuals with untreated celiac disease (CD), possibly due to calcium and vitamin D malabsorption, release of pro-inflammatory cytokines, and misbalanced bone remodeling. A gluten-free diet (GFD) promotes a rapid increase in BMD that leads to complete recovery of bone mineralization in children. Children may attain normal peak bone mass if the diagnosis is made and treatment is given before puberty, thereby preventing osteoporosis in later life. A GFD improves, but rarely normalizes, BMD in patients diagnosed with CD in adulthood. In some cases, nutritional supplementation may be necessary. More information on therapeutic alternatives is needed.

Prevalence of low bone mineral density in children and adolescents with celiac disease under treatment

CONTEXT AND OBJECTIVE

Low bone mineral density may be a finding among children and adolescents with celiac disease, including those undergoing treatment with a gluten-free diet, but the data are contradictory. The aim of this study was to determine the frequency of bone mineral density abnormalities in patients on a gluten-free diet, considering age at diagnosis and duration of dietary treatment.

DESIGN AND SETTING

Cross-sectional prevalence study at the Pediatric Gastroenterology Outpatient Clinic of Instituto Materno Infantil Professor Fernando Figueira.

METHODS

Thirty-one patients over five years of age with celiac disease and on a gluten-free diet were enrolled. Bone mineral density (in g/cm(2)) was measured in the lumbar spine and whole body using bone densitometry and categorized using the criteria of the International Society for Clinical Densitometry, i.e. low bone mineral density for chronological age < -2.0 Z-scores. Age at diagnosis and duration of dietary treatment were confirmed according to the date of starting the gluten-free diet.

RESULTS

Low bone density for chronological age was present in 3/31 patients in the lumbar spine and 1/31 in the whole body (also with lumbar spine abnormality). At diagnosis, three patients with low bone mineral density for the chronological age were more than 7.6 years old. These patients had been on a gluten-free diet for six and seven months and 3.4 years.

CONCLUSION

Pediatric patients with celiac disease on long-term treatment are at risk of low bone mineral density. Early diagnosis and long periods of gluten-free diet are directly implicated in bone density normalization.