Serum cytokine patterns are modulated in infants fed formula with probiotics or milk fat globule membranes: A randomized controlled trial.

BACKGROUND: Proteins and lipids of milk fat globule membrane (MFGM) and probiotics are immunomodulatory. We hypothesized that Lactobacillus paracasei ssp. paracasei strain F19 (F19) would augment vaccine antibody and T helper 1 type immune responses whereas MFGM would produce an immune response closer to that of breastfed (BF) infants. OBJECTIVE: To compare the effects of supplementing formula with F19 or bovine MFGM on serum cytokine and vaccine responses of formula-fed (FF) and BF infants. DESIGN: FF infants were randomized to formula with F19 (n = 195) or MFGM (n = 192), or standard formula (SF) (n = 194) from age 21±7 days until 4 months. A BF group served as reference (n = 208). We analyzed seven cytokines (n = 398) in serum at age 4 months using magnetic bead-based multiplex technology. Using ELISA, we analyzed anti-diphtheria IgG (n = 258) and anti-poliovirus IgG (n = 309) concentrations in serum before and after the second and third immunization, respectively. RESULTS: Compared with SF, the F19 group had greater IL-2 and lower IFN-γ concentrations (p<0.05, average effect size 0.14 and 0.39). Compared with BF, the F19 group had greater IL-2, IL-4 and IL-17A concentrations (p<0.05, average effect size 0.42, 0.34 and 0.26, respectively). The MFGM group had lower IL-2 and IL-17A concentrations compared with SF (p<0.05, average effect size 0.34 and 0.31). Cytokine concentrations were comparable among the MFGM and BF groups. Vaccine responses were comparable among the formula groups. CONCLUSIONS: Contrary to previous studies F19 increased IL-2 and lowered IFN-γ production, suggesting that the response to probiotics differs across populations. The cytokine profile of the MFGM group approached that of BF infants, and may be associated with the previous finding that infectious outcomes for the MFGM group in this cohort were closer to those of BF infants, as opposed to the SF group. These immunomodulatory effects support future clinical evaluation of infant formula with F19 or MFGM.

Serum hepcidin in infants born after 32 to 37 wk of gestational age.

BACKGROUND: Preterm infants are at risk of iron deficiency (ID). Hepcidin has been suggested as a good additional indicator of ID in preterm infants, next to ferritin. METHODS: In a prospective observational study, we analyzed serum hepcidin in 111 infants born after 32+0 to 36+6 wk gestational age during the first 4 mo of life. RESULTS: Hepcidin concentrations decreased during the first 4 mo of life, and concentrations were lower in infants with ID compared to those without ID. Infants who developed ID at the age of 4 mo had already significantly lower levels of hepcidin at 1.5 mo of age, while ferritin was already significantly lower at the age of 1 wk. CONCLUSION: Hepcidin concentrations of late preterm infants decrease during the first 4 mo of life. This decrease, which parallels a decrease of ferritin concentration, we interpret as a physiological response, aiming to increase iron availability. Hepcidin concentrations are lower in infants with ID compared with those without ID, with a notable change already observed at 1.5 mo of age. Hepcidin can be used as an early marker of ID, although an additive value of hepcidin over ferritin in the diagnosis of ID is not present.

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.

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.

Serum hepcidin measured by immunochemical and mass-spectrometric methods and their correlation with iron status indicators in healthy children aged 0.5-3 y.

BACKGROUND: The diagnostic use of hepcidin is limited by the absence of standardization and lack of age-specific reference ranges in children in particular. The aim of this study was to determine reference ranges of serum hepcidin in healthy children aged 0.5-3 y using mass spectometry (MS) and a commercial immunochemical (IC) assay, and to investigate its association with other indicators of iron status and inflammation. METHODS: We included 400 healthy children aged 0.5-3 y. We constructed reference ranges for MS-hepcidin and IC-hepcidin concentrations using the median, P2.5, and P97.5 in a normative population of 219 children with no anemia, no infection and/or inflammation, and no iron deficiency. RESULTS: Median concentrations (P2.5-P97.5) of MS-hepcidin and IC-hepcidin were 3.6 nmol/l (0.6-13.9 nmol/l) and 7.9 nmol/l (1.9-28.6 nmol/l), respectively. We found a good correlation between both methods. However, MS-hepcidin was consistently lower than IC-hepcidin. Hepcidin correlated with ferritin and C-reactive protein. CONCLUSION: We provide reference ranges for hepcidin for an MS and commercial IC method. Absolute values between assays differed significantly, but hepcidin concentrations obtained by MS and IC methods correlate with each other, and both correlate with ferritin and CRP.

Transglutaminase IgA antibodies in a celiac disease mass screening and the role of HLA-DQ genotyping and endomysial antibodies in sequential testing.

OBJECTIVES: The aim of this study was to evaluate hypothetical screening strategies in a Swedish celiac disease (CD) mass screening. METHODS: Of 10,041 Swedish sixth graders born in 1993 invited to a population-based CD mass screening, 7208 participated. Anti-tissue transglutaminase (tTG) immunoglobulin (Ig) A were analyzed in all children and total serum IgA (s-IgA) in 7161 children. Additional analyses of tTG-IgG, endomysial antibodies (EMA) IgA and IgG, and human leukocyte antigen (HLA) alleles were performed according to a standardized protocol. Children with elevated levels of serological markers were recommended to undergo a small intestinal biopsy to verify diagnosis, and 153 children with CD were thus identified. Sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs) were calculated and receiver operating characteristic curves were plotted. RESULTS: By lowering the cutoff for tTG-IgA, 17 additional cases of CD were identified at the cost of 32 biopsies. All children with tTG-IgA >50 U/mL (10 times the recommended upper limit of normal) had gluten enteropathy. Area under the receiver operating characteristic curve for tTG-IgA was 0.988. All cases carried HLA-DQ2 or HLA-DQ8, as did 53% of the controls. For different hypothetical screening strategies, sensitivity, specificity, PPV, and NPV ranged between 87.6% and 100%, 99.5% and 99.9%, 79.7% and 89.7%, and 99.7% and 100%, respectively. Efforts to increase sensitivity by lowering tTG-IgA cutoff would result in increased number of small intestinal biopsies and lower PPV. Sequential testing for both EMA and HLA-DQ genotyping would reduce the number of negative small intestinal biopsies. CONCLUSIONS: tTG-IgA is a robust marker when used in CD mass screening and its performance can be enhanced by sequential testing for EMA or HLA-DQ genotyping.

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.

Antigliadin immunoglobulin A best in finding celiac disease in children younger than 18 months of age.

OBJECTIVES: The aim was to investigate age-dependent serum levels and occurrence of elevated celiac disease (CD)-related antibodies in young children, to define the optimal serological procedure when selecting for small intestinal biopsy. PATIENTS AND METHODS: Included were 428 children with biopsy verified CD (median age 16 months; range 7.5 months-14 years) and 216 controls (median age 2.7 years; range 8.5 months-14.6 years). Immunoglobulin (Ig) A antibodies against gliadin (AGA-IgA), tissue transglutaminase (tTG-IgA), and endomysium (EMA-IgA) were analysed. RESULTS: Increased serum AGA-IgA levels were found in 411 of 428 CD cases, tTG-IgA in 385 of 428, and EMA-IgA in 383 of 428. In the control group, 11 of 216 had increased levels of AGA-IgA, 5 of 216 of tTG-IgA, and 8 of 216 of EMA-IgA. In CD children younger than 18 months, elevated AGA-IgA occurred in 97% and elevated tTG-IgA and EMA-IgA were found in 83% of the cases. Conversely, in CD children older than 18 months, elevated AGA-IgA occurred in 94%, and elevated tTG-IgA and EMA-IgA were found in 99% of the cases. CONCLUSIONS: In children older than 18 months, both tTG-IgA and EMA-IgA are sufficiently accurate to be used as a single antibody marker, whereas a large proportion of younger children with CD lack these antibodies. Therefore, when selecting children for small intestinal biopsy, the detection of a combination of AGA-IgA and tTG-IgA is optimal for identifying untreated CD in children younger than 18 months.

Antiendomysial and antihuman recombinant tissue transglutaminase antibodies in the diagnosis of coeliac disease: a biopsy-proven European multicentre study.

OBJECTIVE: To investigate the value of serum antitissue transglutaminase IgA antibodies (IgA-TTG) and IgA antiendomysial antibodies (IgA-EMA) in the diagnosis of coeliac disease in cohorts from different geographical areas in Europe. The setting allowed a further comparison between the antibody results and the conventional small-intestinal histology. METHODS: A total of 144 cases with coeliac disease [median age 19.5 years (range 0.9-81.4)], and 127 disease controls [median age 29.2 years (range 0.5-79.0)], were recruited, on the basis of biopsy, from 13 centres in nine countries. All biopsy specimens were re-evaluated and classified blindly a second time by two investigators. IgA-TTG were determined by ELISA with human recombinant antigen and IgA-EMA by an immunofluorescence test with human umbilical cord as antigen. RESULTS: The quality of the biopsy specimens was not acceptable in 29 (10.7%) of 271 cases and a reliable judgement could not be made, mainly due to poor orientation of the samples. The primary clinical diagnosis and the second classification of the biopsy specimens were divergent in nine cases, and one patient was initially enrolled in the wrong group. Thus, 126 coeliac patients and 106 controls, verified by biopsy, remained for final analysis. The sensitivity of IgA-TTG was 94% and IgA-EMA 89%, the specificity was 99% and 98%, respectively. CONCLUSIONS: Serum IgA-TTG measurement is effective and at least as good as IgA-EMA in the identification of coeliac disease. Due to a high percentage of poor histological specimens, the diagnosis of coeliac disease should not depend only on biopsy, but in addition the clinical picture and serology should be considered.