Intestinal microbiota and allergic diseases: A systematic review.

Evidence suggests that possible imbalances in intestinal microbiota composition may be implicated in the occurrence of allergic diseases. Although several studies published until 2006 indicated a correlation between microbiota composition and allergic symptoms, it has not been possible to distinguish protective microorganisms from those associated with increased risk of allergic diseases. Therefore, the objective of this study was to review the studies published since 2007 that address the intestinal microbiota in allergic diseases. Twenty-one studies were identified after excluding those that performed a clinical intervention before stool collection. In the early microbiota of children who later developed allergies, lower bacterial diversity was observed, with a predominance of Firmicutes; a higher count of Bacteroidaceae; a higher prevalence of the anaerobic bacteria Bacteroides fragilis, Escherichia coli, Clostridium difficile, Bifidobacterium catenulatum, Bifidobacterium bifidum, and Bifidobacterium longum; and a lower prevalence of Bifidobacterium adolescentis, B. bifidum, and Lactobacillus. In the microbiota of allergic children whose intestinal microbiota was assessed at the onset of allergic symptoms, there was a higher count of Bacteroides; a lower count of Akkermansia muciniphila, Faecalibacterium prausnitzii, and Clostridium; a higher prevalence of B. adolescentis; a lower prevalence of B. catenulatum and Staphylococcus aureus; and a lower bacterial diversity.

Low-dietary fiber intake as a risk factor for recurrent abdominal pain in children.

OBJECTIVE: To evaluate dietary fiber intake in children with recurrent abdominal pain. DESIGN: Cross-sectional study with control group. SETTING: Outpatients of the Pediatric Gastroenterology public health clinic of the Darcy Vargas Children's Hospital, Brazil. SUBJECTS: Forty-one patients with recurrent abdominal pain were evaluated and 41 children, as a control group. INTERVENTIONS: Macronutrients and fiber intake evaluation by the Daily Food Intake method. Two tables of fiber composition in foods were used. RESULTS: According to the Brazilian table the mean intake of fiber (g/day) by the children of the recurrent abdominal pain groups with chronic constipation or not, and the control group was, respectively, 18.2, 16.6 and 23.7 for total fiber (P=0.001), 7.5, 6.9 and 9.5 for soluble fiber (P=0.001) and 10.7, 9.7 and 14.1 for insoluble fiber (P=0.002). According to the AOAC table, the recurrent abdominal pain group with chronic constipation or not (10.6 and 9.9 g/day) also had lower intake of total fiber than the control group (13.4 g/day) (P=0.008). The intake of fiber was lower than the minimum recommended value (age+5 g) and statistically associated (P=0.021) with the recurrent abdominal pain group (78%) in comparison with the control one (51.2%). The odds ratio was 3.39 (95% CI, 1.18-9.95). CONCLUSION: fiber intake below the minimum recommended value is a risk factor for recurrent abdominal pain in children.

[Celiac disease: evaluation of compliance to gluten-free diet and knowledge of disease in patients registered at the Brazilian Celiac Association (ACA)]. / Doença celíaca: avaliação da obediência à dieta isenta de glúten e do conhecimento da doença pelos pacientes cadastrados na Associação dos Celíacos do Brasil (ACELBRA).

BACKGROUND: The compliance to a gluten-free diet may prevent the development of both non-malignant and malignant complications. AIM: To evaluate compliance to a gluten-free diet and knowledge of the disease in celiac patients registered at the Brazilian Celiac Association (BCA). METHODS: A structured questionnaire was designed to assess compliance to a gluten-free diet as well as knowledge of the celiac disease. It was mailed to 584 members of BCA. RESULTS: Five hundred and twenty nine (90.6%) of a total of 534 (91.4%) answered questionnaires were analyzed; 69.4% were classified as compliant patients whereas 29.5% were classified as noncompliant. The proportion of patients age 21 or older who consume gluten frequently or without any restriction is larger (17.7%) than those who were younger than 21 years (9.9%). Frequency of dietary compliance was higher when the diagnosis had taken less than 5 years to be established; 82% of the patients replied that the small intestine was the part of the body affected by the disease. The most common symptoms of the disease according to the answers were diarrhea (96.6%), weight loss (93.4%), protuberant abdomen (90.4%), anemia (68.1%) and vomiting (59.6%). Only 59.0% agreed with the existence of genetic predisposition; 90.4% answered that the disease is permanent and 96.2% stated that the diet should exclude gluten absolutely; 67.1% answered that the gluten is a protein and according to 92.1% questionnaires this protein is present in wheat, rye, barley and oat. Greater compliance was observed when there was an understanding of the disease and diet. The small intestine biopsy was considered necessary for just 67.5% of the patients, and greater compliance was observed in patients who had undergone at least one small intestine biopsy. CONCLUSION: Our findings indicate that the more the patients know and understand about the disease, the better able they are to comply with the diet.

Cow's milk protein intolerance and chronic constipation in children.

Cow's milk protein (CMP) allergy was investigated in 25 children (age-range 3 months to 11 years) with chronic constipation. A diagnosis of constipation was made on the basis of a history of painful elimination of hard stools for at least 1 month, whether or not associated with a reduced frequency of stools or soiling. The children were evaluated using clinical parameters and the following laboratory tests: total serum immunoglobulin E (IgE); specific IgE (radioallergosorbent test [RAST]) for whole cow's milk, alpha-lactoalbumin, beta-lactoglobulin, and a food group; and skin-prick tests with whole milk, alpha-lactoalbumin, beta-lactoglobulin, and casein. Following the evaluation, the children were submitted to a CMP-free diet for a period of 4 weeks. In seven patients (28%), constipation disappeared during the CMP-free diet and reappeared within 48-72 h following challenge with cow's milk. In two infants a rectal biopsy revealed allergic colitis and they therefore did not undergo the challenge. High serum levels of total IgE were observed in five of the children who showed a clinical improvement (71%), a positive skin-test in two (29%), and detectable specific IgE in two (29%). These results suggest that CMP allergy or intolerance should be considered as a cause of chronic refractory constipation in children, although the underlying mechanism still require further investigation.

[Assessment of gliadin in pharmaceutical products - important information to the orientation of celiac disease patients]. / Pesquisa de gliadina em medicamentos--informação relevante para a orientação de pacientes com doença celíaca.

BACKGROUND: Some drugs might contain gliadin which can be dangerous for celiac disease patients. OBJECTIVE: Detect gliadin in pharmaceutical products commonly used in Brazil. METHODS: We analyzed 78 pharmaceutical products selected aleatory from a list of 180 products most frequently sold at Brazilian community pharmacies. The analyzed samples were analgesics (n = 9), anthelmintics (n = 3), antacids (n = 8), antibiotics (n = 13), anticholesteremics (n = 1), anticonvulsants (n = 2), antidepressants (n = 2), antiemetics (n = 3), antihypertensives (n = 3), antihistaminics (n = 3), anti-inflammatories (n = 7), antipyretics (n = 2), bronchodilators (n = 1), laxatives (n = 1), oral contraceptives (n = 5) and vitamins (n = 10). The samples were analyzed by enzyme immunoassay based on monoclonal antibodies omega-gliadins, the elected technique according to the Codex Alimentarius Commission WHO/FAO. All samples were analyzed in duplicate. The sensitivity of this test is 4 mg of gliadin/100 g of product. RESULTS: Only one (1.3%) out of 78 pharmaceutical products contained detectable amounts of gliadin (5.5 mg/100 g). The active ingredient of this drug is ranitidine. According to the Codex Alimentarius Commission WHO/FAO the intake of 10 mg of gliadin/day should not be exceeded by celiac disease patients. Considering the amount of gliadin in each capsule of ranitidine, the ingested quantity would be lower than the maximum allowed for celiac patients. CONCLUSIONS: In this study gliadin was not detected in pharmaceutical products in harmful amount for celiac disease patients.

Clinical usefulness of acid steatocrit in pediatric practice.

The steatocrit technique has been frequently used in the follow up of malabsorption syndromes. The classical steatocrit method has recently been improved by adding perchloric acid to the fecal homogenate (acid steatocrit), this technique showed a better correlation with fecal fat concentration than the classical test. In our protocol, we aimed at an assessment of the clinical usefulness of the acid steatocrit when compared to the traditional technique. Children who were referred to the laboratory for evaluation of steatorrhea were studied by the fecal fat balance, which was taken as a gold standard method for the comparison between both steatocrits. The method was slightly modified, by using hydrochloric instead of perchloric acid. Our results showed a sensitivity of 88.8% for the acid steatocrit and 66.7% for the classical method, at a 1.6% cut off value. We suggest the method as useful to rule out steatorrhea, thus selecting those children who should not be submitted to more laborious and time consuming methods such as the fecal fat balance.

[Breath hydrogen test to evaluate lactose absorption and small bowel bacterial overgrowth in children]. / Teste do H2 no ar expirado na avaliação de absorção de lactose e sobrecrescimento bacteriano no intestino delgado de escolares.

The aim of this study was to determine the lactose absorption capacity and possible existence of bacterial overgrowth in the small bowel in asymptomatic school children of low social economic level in Marilia, a city located in the interior of São Paulo state. Eighty three children aging 7 to 15 years old without any gastrointestinal manifestations at least 30 days prior to the tests were studied. All the patients had fasted for at least 8 hours before the tests were performed. Lactose absorption was evaluated by breath hidrogen test after an overload of lactose 18 g in 10% aquous solution. Lactose intolerance was determined by the occurrence of clinical symptoms, such as diarrhea, abdominal pain, flatulence, etc in the following 24 hours after the test was performed. Bacterial overgrowth was evaluated by the breath hidrogen test after a 10 g lactulose load in aqueous solution. Lactose malabsorption was detected in 19 (22.9%) children and lactose intolerance was observed in 10 (12%) children. Lactose intolerance was more frequently observed in children who showed lactose malabsorption (6/19; 31.6%) than in those who presented a normal test (4/64; 6.3%) (P = 0.008). Bacterial overgrowth was detected in six (7.2%) children and showed no statistical relationship with lactose malabsorption. Ontogenetic lactose malabsorption verified in this group of school children is similar to the reported for Caucasian populations. Presence of bacterial overgrowth confirms the existence of asymptomatic environmental enteropathy in children of low social economic level.

[Celiac disease: evolution in knowledge since its original centennial description up to the present day]. / Doença celíaca: a evolução dos conhecimentos desde sua centenária descrição original até os dias atuais.

In the recent past, some celiac disease features have been discussed in literature specially related to genetic susceptibility, pathogenesis, clinical presentation and diagnostic criteria. Immunological abnormalities characteristic of celiac disease, such as circulating antibodies and increased numbers of intra-epithelial lymphocytes containing a high percentage of gamma-delta T cells have been demonstrated. Other pictures of clinical presentation besides the classical one deserve attention namely short stature, iron-resistant anaemia, enamel hypoplasia, constipation, neurological manifestation and osteoporosis, among others. Asymptomatic presentation has been recognized since development of serological markers such as anti-gliadin, anti-reticulin and anti-endomysium antibodies. Up to now, small intestinal biopsy is the only decisive diagnostic approach. A Federal law has recently imposed food manufactures to place labels informing the presence of gluten in industrialized foods in Brazil. Lately there has been an increase in celiac disease patients registered in the Brazilian Celiac Association.

[Estimated dietary fiber intake in children according to different food composition reference tables]. / Estimativa do consumo de fibra alimentar por crianças de acordo com diferentes tabelas de composição de alimentos.

The importance of dietary fiber intake in the prevention and treatment of adult diseases has been widely emphasized in the literature for several years. Recommendations for fiber intake by children have only recently began to be published. The present study estimated the fiber intake by children with or without constipation according to five food composition tables. We studied 114 children under 12 years of age, of whom 56 were constipated and 58 had normal bowel movements. We used a 24 hour recall questionnaire and fiber consumption was analysed by five food composition tables: 1. Association of Official Agricultural Chemist-AOAC, 2. Southgate, 3. Mendez, 4. Englyst and 5. crude fiber. The statistical analysis showed significant differences between the medians of the estimated fiber consumption calculated using all tables, except the AOAC and Southgate tables. The median value and percent is 25th and 75th presented between parenthesis were (grams/day): Mendez--15.4 (11.9-19.6); Southgate--10.5 (7.8-13.5); AOAC--10.2 (7.3-14.0); Englyst--4.5 (3.0-6.0) and crude fiber--2.1 (1.4-2.9). There were statistical significant correlations between all pairs of tables but the best correlation was observed between Mendez and Southgate (r = +0.90), AOAC and Southgate (r = +0.88); and Mendez and AOAC (r = +0.84). Constipated children presented lower estimated fiber intake than those with normal bowel movements, with statistical significance according to all tables. In conclusion, it is important to determine which reference table should be utilized when recommending dietary fiber.

[Severe acute diarrhea associated to classic enteropathogenic Escherichia coli (EPEC): clinical features and fecal losses in hospitalized infants]. / Diarréia aguda grave associada à Escherichia coli enteropatoênica clássica (EPEC): características clínicas e perdas fecais em lactentes hospitalizados.

UNLABELLED: Enteropathogenic Escherichia coli (EPEC) strains are the most prevalent enteropathogenic agents isolated in the stools of hospitalized infants with severe acute diarrhea in São Paulo. These microorganisms induce a severe intestinal secretion of fluids and electrolytes that can cause dehydration leading to hospital admission in the majority of the cases. OBJECTIVES: This investigation aims at the following objectives: 1) to study the clinical features of acute diarrhea in male infants who were hospitalized owing to EPEC infection; 2) to determine the fecal fluid losses, formula intake and variation of the body weight during the evolution of the disease. PATIENTS AND METHODS: Thirty eight male infants with acute diarrhea due to EPEC strains were studied. The clinical and epidemiological features of the patients were recorded and the different EPEC serogroups were identified. The infants were kept in a metabolic bed in order to allow the collection of stools and urine separately during the whole period of the disease, and daily metabolic balances were also obtained. The mean duration of the metabolic study was 5.8 days, and during this period of time 220 daily metabolic balances were accumulated and analyzed. RESULTS: The main clinical features of the studied group were as follows: age below 12 months; low birth weight; precocious weaning; severe protein-calorie malnutrition. EPEC 0111 was the most frequent serogroup identified, present in 68.4% of the infants. The average daily fecal fluid losses were 66 ml/kg and the mean daily formula intake was 85.2 ml/kg. Cow's milk was the most precocious food utilized and the infants who received cow's milk feeding presented the largest stool losses in comparison with lactose free formulas and total parenteral nutrition. CONCLUSION: EPEC strains are able to induce moderate to severe fecal fluid losses in infants and the duration of diarrhea is usually below 15 days, although in several circumstances diarrhea can show a protracted evolution owing to food intolerance associated or not with intestinal secretion.

Asymptomatic giardiasis does not affect iron absorption in children with iron deficiency anemia.

OBJECTIVE: Malabsorption of iron has been reported in children with symptomatic giardiasis. The aim of this study was to evaluate intestinal absorption of iron in children with asymptomatic giardiasis and iron deficiency anemia. SUBJECTS: Based upon results of blood hemoglobin and stool examination, two groups were established: asymptomatic giardiasis and anemia, and anemia without intestinal parasitosis (control group). Patients were aged 1-6 years. There was no difference in age, weight, height, or iron nutritional status between the asymptomatic giardiasis and control groups on admission to the study. MEASURES: Intestinal absorption of iron was evaluated using the iron tolerance test and the hemoglobin response to iron therapy. The serum iron tolerance test was based on the increment of iron level 2 hours after administering an iron load of 1 mg/kg of elemental iron in the form of ferrous sulfate, in comparison to the fasting iron level. Hemoglobin response to oral iron therapy was determined by the increment of hemoglobin on day 30 of therapy with ferrous sulfate (5 mg/kg/day of elemental iron). RESULTS: There was no statistical difference between the asymptomatic giardiasis and control groups with reference to the iron tolerance test (159.1 +/- 73.1 micrograms/dl and 154.5 +/- 76.5 micrograms/dl, respectively) and to the hemoglobin response to iron therapy (1.5 +/- 0.7 g/dl and 1.8 +/- 1.1 g/dl, respectively). The presence or absence of trophozoites of Giardia lamblia on duodenal aspirate did not affect intestinal absorption of iron. CONCLUSION: Asymptomatic giardiasis did not affect the intestinal absorption of iron and the hemoglobin response to oral iron therapy in iron-deficient anemic children.

[Diagnostic limitations of the physical examination in the identification of children with anemia]. / Limitação diagnóstica do exame físico na identificação de crianças com anemia.

A total of 143 children was randomly selected from a Pediatric out-patients clinic in order to evaluate the accuracy and reproductibility of the clinical signs of anemia. The patients, who ranged from 6 to 68 months old, were assessed on the basis of 2 clinical examinations performed independently by 2 physicians. Clinical diagnosis of anemia relied upon the examination for the presence of pallor through an inspection of the skin, conjunctivaes, lips, tongue and palms. The reference standard taken into consideration was hemoglobin in venous blood samples. The prevalence of anemia (hemoglobin < 11.0 g/dL) consisted of 41.3%, predominating among patients who ranged from 6 to 24 months old (59.3%). The sensitivity of the different clinical signs for the 2 examinations was low ranged from 28.8% to 52.5%. Almost all the children with hemoglobin concentration lower than 9.0 g/dL presented at least one suggestive clinical sign of anemia. The Kappa coefficient (K) demonstrated a mild agreement between the 2 examinations for the assessment of cutaneous pallor (K = +0.32) and moderate agreement for the evaluation of the conjunctivaes, lips-tongue and palms (K from +0.55 to +0.59). In view of limitation of the accuracy and reproductibility of the clinical signs of anemia, we may state that the determination of hemoglobin concentration should be introduced as a routine procedure of major importance in health care services.

[Intake of dietary fiber and other nutrients by children with and without functional chronic constipation]. / Teor de fibra alimentar e de outros nutrientes na dieta de crianças com e sem constipação intestinal crônica funcional.

The aim of this study was to evaluate the dietary fiber intake and the dietary habits of children with and without functional chronic constipation. We enrolled 58 children with functional chronic constipation and 58 controls without constipation matched for sex and age. Food and fiber intake were evaluated by 24 hour dietary recall and a complete clinical history was performed. The age of onset of constipation occurred during the first year of life in 55.4% of the patients while the median age of evaluation was 78 months. Soiling was found in 41.7% of patients. The median period of exclusive breast feeding was shorter (P = 0.002) in the constipation group (one month) than in the control group (three month). The proportion of constipation was similar for mothers of children of both groups as well as for siblings in both groups. The fathers of children with constipation presented higher frequency of constipation (12.3%) than the fathers of children in control group (1.8%), but the difference did not reach statistical significance (P = 0.06). The amount of food measured by 24 hour recall was similar in both groups. The calorie intake of constipated children (1526 +/- 585 calories/day) was lower (P = 0.07) than in the control group (1712 +/- 513 calories/day) but the difference did not reach statistical significance. The intake of protein, fat and iron was lower in the constipation group than in the control group. The volume of cow's milk intake was similar in both groups. The median of total dietary fiber intake in the constipation group (13.5 g/day) was statistically (P = 0.009) lower than in the control group (16.8 g/day). The daily intake of insoluble dietary fiber was also statistically lower (P = 0.001) in the constipation group (6.3 g) than in the control group (9.4 g). The intake of soluble dietary fiber was similar in both groups. The intake of dietary fiber per 1,000 calories of diet was 10.3 g in the constipation group and 10.4 in the control group (P = 0.41). There was a considerable intersection of individual values in fiber intake of the constipation and control groups, suggesting that low fiber intake acts in association with others factors on the genesis of constipation in children. However, the low intake of insoluble fiber, suggests that it plays an important role on the pathogenesis of chronic constipation in children.

[Serum antigliadin antibodies in the diagnosis and follow-up of celiac disease]. / Anticorpo sérico antigliadina no diagnóstico e seguimento da doença celíaca.

Between July 1985 and June 1990, we prospectively investigated 236 children suspected of having malabsorption syndrome. Each patient had a xylose absorption test and small intestinal biopsy. Blood samples were collected to AGA assay. The aim of the study was to evaluate the use of antigliadin antibodies test, IgG and IgA, in screening celiac disease for intestinal biopsy and in the monitoring of gluten-free diet and challenge in celiac patients. Twenty patients were diagnosed with celiac disease confirmed by three small intestinal biopsies; 12 patients were suspected of having celiac disease, with two biopsies, before and one year after a gluten-free diet; 106 patients had environmental enteropathy; 45 patients had protracted diarrhea and 56 children had failure to thrive with no gastrointestinal symptoms. The AGA test was considered a reliable test in screening for biopsy and in the differential diagnosis between celiac disease and other causes of malabsorption syndrome. The IgG AGA test had high sensitivity (90.4%) and the IgA AGA test had high specificity (92.1%) in screening for celiac disease. In the follow-up of the celiac patients the antibody levels were significantly higher during gluten containing diet than after gluten avoidance being thus a reliable test to evaluate dietary compliance.

[Diagnostic limitations of the isolation of trophozoites of Giardia lamblia in duodenal aspirates]. / Limitação diagnóstica da pesquisa de trofozoítos da Giardia lamblia no aspirado duodenal.

Examination of fecal specimens for detection of Giardia lamblia cysts is known to produce a high percentage of false negative results while it is generally believed that duodenal juice often contains trophozoites even when the stool examination is negative. The aim of this study was to compare the detection of trophozoites in duodenal aspirate with the findings of cysts in stool samples for the diagnosis of asymptomatic giardiasis. Forty five children with iron deficiency anemia (one to six years of age) were studied, 21 with giardiasis and 24 without giardiasis. For each subject, one to five stool samples were examined for cysts of Giardia lamblia employing the formol-ether concentration method. Duodenal juice from all children were examined for the presence of trophozoites of Giardia lamblia. Fecal excretion of cysts was demonstrated in 20 (95%) of the 21 patients with giardiasis; however, only nine (43%) exhibited the presence of trophozoites in their duodenal aspirates. In one child trophozoites were observed in the duodenal aspirate; but the parasitologic investigation was negative for cysts in the feces. All the children without giardiasis had at least three stool samples and duodenal aspirate negative for Giardia lamblia. In conclusion, fecal examination by formol ether concentration method exhibited a greater number of positive results than did the duodenal aspirate microscopy method in the diagnosis of giardiasis.

[Nutritional status of Indian children of Alto Xingu and evaluation of the use of arm perimeter in the diagnosis of protein-calorie malnutrition]. / Estado nutricional de crianças índias do Alto Xingu e avaliação do uso do perímetro braquial no diagnóstico da desnutrição protéico-calórica.

STUDY OBJECTIVE: The purpose of this study was to determine the presence of malnutrition in indian children of Alto Xingu region in Brazil, and to evaluate the usefulness of arm circumference and QUAC index in the diagnosis of protein-energy malnutrition (PEM). SITE: The indian population of Alto Xingu maintains most of its traditional customs. PATIENTS: 335 children were studied prospectively in at least one of seven consecutive years between 1974 and 1980, and 1278 measurements were obtained of weight, height, and arm circumference. MEASUREMENTS AND RESULTS: The annual prevalence of PEM (weight-for-height) less than 90% according to Brazilian reference tables was 4.1% in children aged under 1 year, 7.3% in children from 1 to 5 years of age, and 7.5% in children older than 5. According NCHS tables, however, values of 1.0%, 2.8%, and 1.1% were obtained for the respective age groups. The sensitivity and specificity of arm circumference and QUAC index were calculated in relation to the weight-for-height relation. According to Brazilian reference tables, arm circumference had a sensitivity of 8.9% and specificity of 99.3%, whereas the QUAC index had a sensitivity of 11.1% and specificity of 98.3%. However, according to NCHS tables, slightly different values were obtained. The sensitivity and specificity in this case were 23.5% and 99.3%, respectively, for arm circumference and 35.3% and 98.3%, respectively, for the QUAC index. CONCLUSIONS: The authors concluded that the prevalence of PEM was low in the Alto Xingu and that arm circumference and the QUAC index should only be used in situations suited to their sensitivity and specificity.