High adherence to a gluten-free diet in adolescents with screening-detected celiac disease.

OBJECTIVES: The aim of the study was to evaluate the gluten-free diet (GFD) adherence after 1 year of follow-up in children with screening-detected celiac disease (CD) in a general population. METHODS: A total of 18,325 twelve-year-olds were invited to participate in a population-based CD screening (Exploring the Iceberg of Celiacs in Sweden), of whom 13,279 participated. In 240 children, CD was detected through elevated anti-tissue transglutaminase antibodies 2 (TG2-IgA) and verified by a small-intestinal biopsy. This substudy included 210 children with TG2-IgA, evaluated both at the initial biopsy occasion and at 1-year follow-up. GFD adherence was evaluated by a combination of TG2-IgA measurements and self-reported adherence (n = 193). RESULTS: After 1 year, 85% (179/210) had normalized TG2-IgA levels (<5 U/mL). Among those who had >50 U/mL at diagnosis, 25% (16/63) still had elevated TG2-IgA, but for the majority their initial values were more than halved. Most reported a high level of GFD adherence ("always" 82% [158/193] and "often" 16% [30/193]), and 75% [145/193] reported always adhering combined with normalized TG2-IgA. Although reporting that they were always adherent, 13 (6.7%) had not yet normalized their TG2-IgA levels completely; however, a majority of these initially had the highest TG2-IgA levels. CONCLUSIONS: GFD adherence is high in adolescents with CD detected by screening of the general population of Swedish 12-year-olds. Almost all of them had normalized serology and reported GFD adherence at the 1-year follow-up. A few adolescents who reported GFD adherence, however, had elevated TG2-IgA levels, suggesting more severe disease and/or nonadherence.

Celiac disease can be predicted by high levels of anti-tissue transglutaminase antibodies in population-based screening.

OBJECTIVES: The aim of the present study was to evaluate any potential correlation between anti-tissue transglutaminase antibodies of type immunoglobulin A (tTG-IgA) and the degree of gluten-induced enteropathy in children participating in a screening study for celiac disease (CD) and to assess to what extent the revised European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) guidelines cover this group of patients. METHODS: The present study is a substudy of a cross-sectional CD screening study, Exploring the Iceberg of Celiacs in Sweden, a 2-phased study performed during 2005 to 2006 and 2009 to 2010. The 13,279 participating children had a blood test obtained, and those with positive tTG-IgA were recommended a small intestinal biopsy. The tTG-IgA levels at the time of biopsy were compared with those at the assessment of the biopsy. RESULTS: There were 267 children included, of whom 230 were diagnosed as having CD. Of all of the children, 67 children had low tTG-IgA levels (<5 U/mL), of whom 55% had Marsh 3 lesions. All of the children with tTG-IgA levels exceeding 10 times the upper limit of normal values of 5 U/mL, that is, 50 U/mL, were diagnosed as having CD. Lowering the cutoff to 3 U/mL, all but 1 child with 30 U/mL got CD diagnosis. CONCLUSIONS: By adopting the revised ESPGHAN criteria, biopsies could have been omitted in one-fourth of all of the patients. Our results indicate that the criteria may be useful even in screened children. Further studies are needed to confirm whether the 2012 ESPGHAN guidelines should be revised to also apply to the populations being screened.

Five-year follow-up of new cases after a coeliac disease mass screening.

OBJECTIVE: We previously performed a population-based mass screening of coeliac disease in children aged 12 years in two birth cohorts resulting in 296 seropositive children, of whom 242 were diagnosed with coeliac disease after duodenal biopsies. In this follow-up study, we wanted to identify new cases in the screening population that tested negative-either converting from potential coeliac disease (seropositive but normal duodenal mucosa) or converting from seronegative at screening to diagnosed coeliac disease. METHODS: All seropositive children were invited to a follow-up appointment 5 years after the screening with renewed serological testing and recommended endoscopic investigation if seropositive. Seronegative children in the screening study (n=12 353) were linked to the National Swedish Childhood Coeliac Disease Register to find cases diagnosed in healthcare during the same period. RESULTS: In total, 230 (77%) came to the follow-up appointment, including 34 of 39 with potential coeliac disease. Of these, 11 (32%) had converted to coeliac disease. One new case was found in the National Swedish Childhood Coeliac Disease Register who received the diagnosis through routine screening in children with type 1 diabetes. CONCLUSIONS: There is a high risk of conversion to coeliac disease among those with potential disease. However, a negative screening test was associated with a very low risk for a clinical diagnosis within a follow-up period of 5 years.

Accuracy in celiac disease diagnostics by controlling the small-bowel biopsy process.

OBJECTIVES: In a Swedish celiac disease screening study (Exploring the Iceberg of Celiacs in Sweden), we systematically reviewed the clinical diagnostic procedures with the aim to evaluate the diagnostic accuracy and to take advantage of lessons learned for improving diagnostic routines. MATERIALS AND METHODS: A school-based celiac disease screening study involving 5 Swedish centers, with 10,041 invited 12-year-olds with 7567 consenting participation. All 192 children with elevated serological markers were recommended to undergo small-bowel biopsy, performed and evaluated according to local clinical routines. All of the mucosal specimens were reevaluated by 1 and, when needed, 2 expert pathologists to reach diagnostic consensus. RESULTS: Small-bowel biopsies were performed in 184 children: 130 by endoscopy and 54 by suction capsule. Endoscopic biopsies were inconclusive in 0.6%, compared with 7.4% of biopsies by suction capsule. A patchy enteropathy was found in 9.1%. Reevaluation by the expert pathologist resulted in 6 additional cases with celiac disease and 1 cleared. Sixteen children with normal or inconclusive biopsies, 4 after endoscopy, and 12 after suction capsule were endoscopically rebiopsied, resulting in another 8 cases. The celiac disease prevalence of 30 of 1000 (95% confidence interval 26-34) was not statistically different from that previously reported. CONCLUSIONS: The present review revealed the importance of controlling each step of the diagnostic procedure. Several cases would have been missed by relying only on local routines. To improve the quality of childhood celiac disease diagnostics, we recommend multiple endoscopic biopsies from both proximal and distal duodenum and standardized evaluation by a pathologist with good knowledge of celiac disease.

Celiac disease revealed in 3% of Swedish 12-year-olds born during an epidemic.

OBJECTIVE: Sweden experienced a marked epidemic of celiac disease between 1984 and 1996 in children younger than 2 years of age, partly explained by changes in infant feeding. The objective of this study was to determine the prevalence of celiac disease in 12-year-olds born during the epidemic (1993), including both symptomatic and screening detected cases. PATIENTS AND METHODS: All sixth-grade children in participating schools were invited (n = 10,041). Symptomatic and, therefore, previously diagnosed celiac disease cases were ascertained through the National Swedish Childhood Celiac Disease Register and/or medical records. All serum samples were analyzed for antihuman tissue transglutaminase (tTG)-IgA (Celikey), and serum-IgA, and some for tTG-IgG and endomysial antibodies. A small intestinal biopsy was recommended for all children with suspected undiagnosed celiac disease. RESULTS: Participation was accepted by 7567 families (75%). Previously diagnosed celiac disease was found in 67 children; 8.9/1000 (95% confidence interval [CI] 6.7-11). In another 192 children, a small intestinal biopsy was recommended and was performed in 180. Celiac disease was verified in 145 children, 20/1000 (95% CI 17-23). The total prevalence was 29/1000 (95% CI 25-33). CONCLUSIONS: The celiac disease prevalence of 29/1000 (3%)-with two thirds of cases undiagnosed before screening-is 3-fold higher than the usually suggested prevalence of 1%. When these 12-year-olds were infants, the prevailing feeding practice was to introduce gluten abruptly, often without ongoing breast-feeding, which might have contributed to this unexpectedly high prevalence.

Prevalence of childhood celiac disease and changes in infant feeding.

OBJECTIVES: Between 1984 and 1996, Sweden experienced an "epidemic" of clinical celiac disease in children <2 years of age, attributed partly to changes in infant feeding. Whether infant feeding affects disease occurrence and/or the clinical presentation remains unknown. We investigated and compared the total prevalence of celiac disease in 2 birth cohorts of 12-year-olds and related the findings to each cohort's ascertained infant feeding. METHODS: A 2-phase cross-sectional screening study was performed in which 13 279 children from 2 birth cohorts participated: children born during the epidemic (1993) and children born after the epidemic (1997). Previously diagnosed cases were reported and confirmed. Blood samples were analyzed for serological markers and children with positive values were referred for small intestinal biopsy. Infant feeding practices in the cohorts were ascertained via questionnaires. Prevalence comparisons were expressed as prevalence ratios. RESULTS: The total prevalence of celiac disease was 29 in 1000 and 22 in 1000 for the 1993 and 1997 cohorts, respectively. Children born in 1997 had a significantly lower risk of having celiac disease compared with those born in 1993 (prevalence ratio: 0.75; 95% confidence interval: 0.60-0.93; P = .01). The cohorts differed in infant feeding (specifically, in the proportion of infants introduced to dietary gluten in small amounts during ongoing breastfeeding). CONCLUSIONS: A significantly reduced prevalence of celiac disease in 12-year-olds indicates an option for disease prevention. Our findings suggest that the present infant feeding recommendation to gradually introduce gluten-containing foods from 4 months of age, preferably during ongoing breastfeeding, is favorable.