Association Between Antibiotics in the First Year of Life and Celiac Disease.

BACKGROUND & AIMS: The intestinal microbiota is believed to be involved in the pathogenesis of celiac disease, in addition to genetic variants and dietary gluten. The gut microbiota is strongly influenced by systemic antibiotics-especially in early life. We explored the association between exposure to a systemic antibiotic in the first year of life and risk of diagnosed celiac disease. METHODS: We performed an observational nationwide register-based cohort study. We included all children born in Denmark from 1995 through 2012 or Norway from 2004 through 2012. Children born in Denmark were followed until May 8, 2015 (age at end of follow-up was 2.3-20.3 years) and children born in Norway were followed until December 31, 2013 (age at end of follow-up was 1-10 years). We collected medical information from more than 1.7 million children, including 3346 with a diagnosis of celiac disease. Exposure to systemic antibiotics was defined as a dispensed systemic antibiotic in the first year of life. RESULTS: Exposure to systemic antibiotics in the first year of life was positively associated with diagnosed celiac disease in the Danish and Norwegian cohorts (pooled odds ratio 1.26, 95% confidence interval 1.16-1.36). We found a dose-dependent relation between an increasing number of dispensed antibiotics and the risk of celiac disease (pooled odds ratio for each additional dispensed antibiotic 1.08, 95% confidence interval 1.05-1.11). No specific type of antibiotic or age period within the first year of life was prominent. Adjustment for hospital admissions with an infectious disease in the first year of life did not change the estimates; adjustment for the number of maternally reported infections in the child in 2 large sub-cohorts decreased the association slightly (pooled odds ratio 1.18, 95% confidence interval 0.98-1.39). CONCLUSION: In a nationwide study of children in Denmark and Norway, we found exposure to systemic antibiotics in the first year of life to be associated with a later diagnosis of celiac disease. These findings indicate that childhood exposure to systemic antibiotics could be a risk factor for celiac disease.

Mode of delivery is not associated with celiac disease.

PURPOSE: The purpose of this study was to investigate the association between mode of delivery and the risk of celiac disease in two large population-based birth cohorts with different prevalence of diagnosed celiac disease. PATIENTS AND METHODS: This is an observational register-based cohort study using two independent population cohorts. We used data from administrative registers and health administrative registers from Denmark and Norway and linked the data at the individual level. We included all children who were born in Denmark from January 1, 1995 to December 31, 2010 and all children who were born in Norway from January 1, 2004 to December 31, 2012. RESULTS: We included 1,051,028 children from Denmark. Cesarean sections were registered for 196,512 children (18.9%). Diagnosed celiac disease was registered for 1,395 children (0.13%). We included 537,457 children from Norway. Cesarean sections were registered for 90,128 children (16.8%). Diagnosed celiac disease was registered for 1,919 children (0.35%). We found no association between the mode of delivery and the risk of diagnosed celiac disease. The adjusted odds ratio for celiac disease for children delivered by any type of cesarean section compared to vaginal delivery was 1.11 (95% CI: 0.96-1.29) in the Danish cohort and 0.96 (95% CI: 0.84-1.09) in the Norwegian cohort. The adjusted odds ratio for celiac disease for children delivered by elective cesarean section compared to vaginal delivery was 1.20 (95% CI: 1.00-1.43) in the Danish cohort and 0.96 (95% CI: 0.79-1.17) in the Norwegian cohort. CONCLUSION: In this large registry-based study, mode of delivery was not associated with an increased risk of diagnosed celiac disease.

Accuracy in Diagnosis of Celiac Disease Without Biopsies in Clinical Practice.

BACKGROUND & AIMS: The guidelines of the European Society of Pediatric Gastroenterology, Hepatology, and Nutrition allow for diagnosis of celiac disease without biopsies in children with symptoms and levels of immunoglobulin A against tissue-transglutaminase (TGA-IgA) 10-fold or more the upper limit of normal (ULN), confirmed by detection of endomysium antibodies (EMA) and positivity for HLA-DQ2/DQ8. We performed a large, international prospective study to validate this approach. METHODS: We collected data from consecutive pediatric patients (18 years or younger) on a gluten-containing diet who tested positive for TGA-IgA from November 2011 through May 2014, seen at 33 pediatric gastroenterology units in 21 countries. Local centers recorded symptoms; measurements of total IgA, TGA, and EMA; and histopathology findings from duodenal biopsies. Children were considered to have malabsorption if they had chronic diarrhea, weight loss (or insufficient gain), growth failure, or anemia. We directly compared central findings from 16 antibody tests (8 for TGA-IgA, 1 for TGA-IgG, 6 for IgG against deamidated gliadin peptides, and 1 for EMA, from 5 different manufacturers), 2 HLA-DQ2/DQ8 tests from 2 manufacturers, and histopathology findings from the reference pathologist. Final diagnoses were based on local and central results. If all local and central results were concordant for celiac disease, cases were classified as proven celiac disease. Patients with only a low level of TGA-IgA (threefold or less the ULN) but no other results indicating celiac disease were classified as no celiac disease. Central histo-morphometry analyses were performed on all other biopsies and cases were carefully reviewed in a blinded manner. Inconclusive cases were regarded as not having celiac disease for calculation of diagnostic accuracy. The primary aim was to determine whether the nonbiopsy approach identifies children with celiac disease with a positive predictive value (PPV) above 99% in clinical practice. Secondary aims included comparing performance of different serological tests and to determine whether the suggested criteria can be simplified. RESULTS: Of 803 children recruited for the study, 96 were excluded due to incomplete data, low level of IgA, or poor-quality biopsies. In the remaining 707 children (65.1% girls; median age, 6.2 years), 645 were diagnosed with celiac disease, 46 were found not to have celiac disease, and 16 had inconclusive results. Findings from local laboratories of TGA-IgA 10-fold or more the ULN, a positive result from the test for EMA, and any symptom identified children with celiac disease (n = 399) with a PPV of 99.75 (95% confidence interval [CI], 98.61-99.99); the PPV was 100.00 (95% CI, 98.68-100.00) when only malabsorption symptoms were used instead of any symptom (n = 278). Inclusion of HLA analyses did not increase accuracy. Findings from central laboratories differed greatly for patients with lower levels of antibodies, but when levels of TGA-IgA were 10-fold or more the ULN, PPVs ranged from 99.63 (95% CI, 98.67-99.96) to 100.00 (95% CI, 99.23-100.00). CONCLUSIONS: Children can be accurately diagnosed with celiac disease without biopsy analysis. Diagnosis based on level of TGA-IgA 10-fold or more the ULN, a positive result from the EMA tests in a second blood sample, and the presence of at least 1 symptom could avoid risks and costs of endoscopy for more than half the children with celiac disease worldwide. HLA analysis is not required for accurate diagnosis. Clinical Trial Registration no: DRKS00003555.

Infant Feeding and Risk of Type 1 Diabetes in Two Large Scandinavian Birth Cohorts.

OBJECTIVE: Our aim was to study the relation between the duration of full and any breastfeeding and risk of type 1 diabetes. RESEARCH DESIGN AND METHODS: We included two population-based cohorts of children followed from birth (1996-2009) to 2014 (Denmark) or 2015 (Norway). We analyzed data from a total of 155,392 children participating in the Norwegian Mother and Child Cohort Study (MoBa) and the Danish National Birth Cohort (DNBC). Parents reported infant dietary practices when their child was 6 and 18 months old. The outcome was clinical type 1 diabetes, ascertained from nationwide childhood diabetes registries. Hazard ratios (HRs) were estimated using Cox regression. RESULTS: Type 1 diabetes was identified in 504 children during follow-up, and the incidence of type 1 diabetes per 100,000 person-years was 30.5 in the Norwegian cohort and 23.5 in the Danish cohort. Children who were never breastfed had a twofold increased risk of type 1 diabetes compared with those who were breastfed (HR 2.29 [95% CI 1.14-4.61] for no breastfeeding vs. any breastfeeding for ≥12 months). Among those who were breastfed, however, the incidence of type 1 diabetes was independent of duration of both full breastfeeding (HR per month 0.99 [95% CI 0.97-1.01]) and any breastfeeding (0.97 [0.92-1.03]). CONCLUSIONS: Suggestive evidence supports the contention that breastfeeding reduces the risk of type 1 diabetes. Among those who were breastfed, however, no evidence indicated that prolonging full or any breastfeeding was associated with a reduced risk of type 1 diabetes.

Validation of celiac disease diagnoses recorded in the Danish National Patient Register using duodenal biopsies, celiac disease-specific antibodies, and human leukocyte-antigen genotypes.

PURPOSE: The purpose of this study was to validate the celiac disease diagnoses recorded in the Danish National Patient Register. To validate the diagnoses, we used information on duodenal biopsies from a national register of pathology reports (the Patobank) and information on celiac disease-specific antibodies and human leukocyte antigen (HLA) genotypes obtained from patient medical records. PATIENTS AND METHODS: We included all the children who were born from 1995 to 2012 and who were registered as having celiac disease in the Danish National Patient Register. We reviewed all the pathology reports on duodenal biopsies in the Patobank and the information in the medical records on celiac disease-specific antibodies (ie, anti-tissue transglutaminase 2 IgA and IgG, endomysial antibodies IgA, and anti-deamidated gliadin peptide IgG) and HLA genotypes. RESULTS: We identified 2,247 children who were registered in the Danish National Patient Register with celiac disease. Duodenal biopsies for 1,555 of the children (69%) were registered in the Patobank; 1,127 (50%) had a biopsy that was compatible with celiac disease (ie, Marsh 2-3). We accessed the medical records of 95% of the children who were registered in the Danish National Patient Register with celiac disease. We found that 1,510 (67%) had one or more positive antibody-test results; 1,120 (50%) had anti-tissue transglutaminase 2, IgA at tenfold or greater the upper limit of the normal range and/or positive endomysial antibody results. The positive predictive value depended on the criteria used for validation and the types and numbers of registrations that were included in the analysis and ranged from 62% (95% confidence interval: 60%-64%) to 86% (95% confidence interval: 84%-87%). CONCLUSION: Our findings indicate that the Danish National Patient Register is a valuable source to identify patients who have been diagnosed with celiac disease. However, validation of the diagnoses is warranted before data on the patients are used for research purposes.