Increased protein absorption after acute gastroenteritis in children

The Gut Microbiome and the Big Eight

Food allergies are increasing at an alarming rate, with 6.5% of the general population affected. It has been hypothesized that the increase in allergies stems from the “hygiene hypothesis”. The gut microbiome, a collection of microbiota and their genetic contents from the gastrointestinal tract, has been shown to play a part in the development of food allergies. The Food and Drug Administration requires all regulated food companies to clearly state an inclusion of the major, or “big eight” food allergens on packaging. This review is to provide information on the significant advancements related to the gut microbiome and each of the eight major food allergies individually. Establishment of causal connection between the microbiome and food allergies has uncovered novel mechanisms. New strategies are discussed to prevent future sensitization and reaction through novel treatments involving functional additives and dietary changes that target the microbiome.

Celiac disease

This review will focus on the pathogenesis, clinical manifestations, diagnosis, and management of celiac disease (CD). Given an increasing awareness of gluten-related disorders, medical professionals of all varieties are encountering patients with a diagnosis of CD or who are thought to have food intolerance to gluten. The prevalence of CD among the general population is estimated to be 1% in Western nations, and there is growing evidence for underdiagnosis of the disease, especially in non-Western nations that were traditionally believed to be unaffected. The development of serologic markers specific to CD has revolutionized the ability both to diagnose and monitor patients with the disease. Additionally, understanding of the clinical presentations of CD has undergone a major shift over the past half century. Although it is well understood that CD develops in genetically predisposed subjects exposed to gluten, the extent of other environmental factors in the pathogenesis of the disease is an area of continued research. Currently, the main therapeutic intervention for CD is a gluten-free diet; however, novel nondietary agents are under active investigation. Future areas of research should also help us understand the relationship of CD to other gluten-related disorders.

Celiac disease risk varies between birth cohorts, generating hypotheses about causality: evidence from 36 years of population-based follow-up

Background

Celiac disease (CD) is a major public health problem with estimated 1-3% prevalence in the general population. In recent years an increase in CD prevalence has been reported both in Sweden and worldwide. This study aimed at examining the annual incidence rate of biopsy-proven celiac disease among children in Sweden over a 36-year period, to assess variations by age, sex and birth cohort, and to assess the clinical impact of these changes.

Methods

The National Swedish Childhood CD Register was used to identify 9107 children aged 0–14.9 years who were diagnosed with CD during the period 1973 to 2009. From 1973 to 1990 the register covered 15% of the nation, this increased to 40% during 1991–1997; a full national coverage was obtained from 1998 onwards. Estimations for the annual incidence rate, cumulative incidence and clinical impact by age groups, calendar month and birth cohorts were made.

Results

CD incidence is continuing to increase in the child population aged 2–14.9 years. A continued variation in CD incidence was observed in children aged 0–1.9 years, characterized by a marked decrease in most recent years. The median age at diagnosis has increased from 1.0 year in the 1970s to 6.8 years in 2009. The average number of new cases has risen from ~200 during 1973–1983 to ~600 during 2004–2009. In the birth cohorts of 2000–2002 the cumulative incidence even exceeded that of the epidemic cohorts at comparable ages. The highest cumulative incidence was observed in the birth cohorts of 1985–1995 and 2000–2002.

Conclusions

CD risk varies between birth cohorts, suggesting cyclic environmental and/or lifestyle risk factors in CD etiology. More research on underlying risk factors is required in order to move forward with preventive strategies.

Early infections are associated with increased risk for celiac disease: an incident case-referent study

BACKGROUND

Celiac disease is defined as a 'chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals'. Sweden has experienced an "epidemic" of celiac disease in children below two years of age. Celiac disease etiology is considered multifactorial; however, little is known regarding potential risk- or protecting factors. We present data on the possible association between early infectious episodes and celiac disease, including their possible contribution to the Swedish celiac disease epidemic.

METHODS

A population-based incident case-referent study (475 cases, 950 referents) with exposure information obtained via a questionnaire (including family characteristics, infant feeding, and the child's general health) was performed. Celiac disease cases were diagnosed before two years of age, fulfilling the diagnostic criteria of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition. Referents were randomly selected from the national population register after fulfilling matching criteria. The final analyses included 954 children, 373 (79%) cases and 581 (61%) referents, with complete information on main variables of interest in a matched set of one case with one or two referents.

RESULTS

Having three or more parental-reported infectious episodes, regardless of type of infection, during the first six months of life was associated with a significantly increased risk for later celiac disease, and this remained after adjusting for infant feeding and socioeconomic status (odds ratio [OR] 1.5; 95% confidence interval [CI], 1.1-2.0; P=0.014). The celiac disease risk increased synergistically if, in addition to having several infectious episodes, infants were introduced to dietary gluten in large amounts, compared to small or medium amounts, after breastfeeding was discontinued (OR 5.6; 95% CI, 3.1-10; P<0.001).

CONCLUSION

This study suggests that having repeated infectious episodes early in life increases the risk for later celiac disease. In addition, we found a synergistic effect between early infections and daily amount of gluten intake, more pronounced among infants for whom breastfeeding had been discontinued prior to gluten introduction. Regarding contribution to the Swedish celiac disease epidemic, which partly was attributed to concurrent changes in infant feeding, early infections probably made a minor contribution via the synergistic effect with gluten amount.

Coeliac disease is associated with intrauterine growth and neonatal infections

To investigate whether factors in the fetal or neonatal period influence the risk of later development of coeliac disease we conducted a population-based register study. The Swedish Medical Birth Register was linked with the Hospital Discharge Register and identified 3392 singleton infants born in the period 1987-97 who developed coeliac disease. Perinatal data for these children were compared with all children born in these years. Exposure variables: Maternal age, parity and smoking habits in early pregnancy, preeclampsia, pregnancy duration and birthweight, birthweight by gestational week, Apgar score, neonatal icterus, neonatal infections, maternal-fetal blood group incompatibility, exchange transfusion, phototherapy. Odds ratios and test-based confidence intervals were calculated. Analyses were made with stratification for year of birth and other risk factors. The risk of developing coeliac disease decreased with maternal age and was lower in first-born than in second-born children. Maternal smoking in early pregnancy was a weak risk factor, as was low birthweight. The most evident risk factors were being exposed to neonatal infections (OR = 1.52, confidence limits 1.19: 1.95) and being small for gestational age (OR = 1.45, confidence limits 1.20; 1.75). These risk factors were independent of each other.

CONCLUSIONS

We have demonstrated that the intrauterine environment, mainly as mirrored by a low birthweight for gestational age and, independently, neonatal infection diagnosis, is associated with the risk of developing coeliac disease, supporting the idea of a multifactorial aetiology of the disease.

Increased frequency of IgM antibodies to cow's milk proteins in Hungarian children with newly diagnosed insulin-dependent diabetes mellitus

We investigated the association between serum antibodies to cow's milk proteins and insulin-dependent diabetes mellitus (IDDM) in Hungarian children. Forty-eight children 1.0-17.1 years of age with newly diagnosed IDDM and 74 control children 1.0-16.0 years of age were studied for serum IgG, IgA and IgM antibodies to cow's milk, beta-lactoglobulin, bovine serum albumin and ovalbumin by enzyme-linked immunosorbent assays. The specificity of IgM antibodies to beta-lactoglobulin and bovine serum albumin was controlled by Western blot. The levels of IgG and IgA antibodies to cow's milk proteins were similar in children with and without IDDM, with the exception of slightly increased levels of IgA antibodies to beta-lactoglobulin in diabetic children (P = 0.05). The levels of IgM antibodies to cow's milk were significantly higher in IDDM patients than in control children (P = 0.0002). Children with IDDM more often had IgM antibodies to beta-lactoglobulin (46.3% vs 18.8%; P = 0.002) and bovine serum albumin (87.8% vs 49.3%, P < 0.0001) than control children. Neither the levels of IgG or IgA antibodies to ovalbumin nor the frequency of IgM antibodies to ovalbumin differed between diabetic and control children.

CONCLUSION

In Hungarian children, clinical manifestation of IDDM is often associated with IgM antibody response to cow's milk protein and its fractions, beta-lactoglobulin and bovine serum albumin, indicating a loss of immunological tolerance to these proteins. IgG and IgA antibodies to cow's milk proteins, associated with an early introduction of cow's milk in diet, seem to play a minor role in the development of childhood IDDM in Hungary.

Gut permeability to human alpha-lactalbumin, beta-lactoglobulin, mannitol, and lactulose in celiac disease

Our objective was to examine the permeability of the gut to protein macromolecules and sugar probes and their possible association in celiac disease patients. We studied the permeability to human alpha-lactalbumin, beta-lactoglobulin, mannitol, and lactulose on 46 occasions in 33 celiac disease patients in various phases of the disease; in addition, mannitol and lactulose permeability was studied in 18 healthy controls. Lactalbumin absorption was detected in 19 of 42 patients tested, more often in celiac disease patients with villous atrophy than in those with normal jejunal biopsy (p = 0.01). Higher absorption of lactalbumin was found in patients with subtotal villous atrophy than in those with normal biopsy (p = 0.02). beta-lactoglobulin was found in four of 42 patients tested. Less mannitol was absorbed by patients with either subtotal or partial villous atrophy than by those with normal histology (p = 0.001 and 0.006, respectively). Lactulose recovery was higher in newly diagnosed patients and patients with subtotal villous atrophy than in controls (p = 0.007 and 0.03, respectively). The lactulose/mannitol ratio was higher in newly diagnosed patients and patients with villous atrophy than in controls (p = 0.002 and 0.002, respectively). The correlation between permeability to lactalbumin and mannitol and lactulose was poor. We conclude that permeability to proteins and sugar molecules is abnormal in celiac disease patients with mucosal damage and that they probably reflect different mechanisms of penetration.