Can bacterial translocation be a beneficial event?

Infection is a major concern in intestinal transplant recipients. Bacterial migration to extraintestinal sites is a central component of the gut hypothesis of sepsis. However, some studies have cited the beneficial effects of bacterial translocation (BT) on the host acquired immune system. We evaluated the role of previous BT on a subsequent BT challenge, examined the BT index in organs as well as changes in white blood cell (WBC) count in mesenteric lymph and blood for correlation with outcomes. Wistar rats (n = 60) were divided into a BT group (n = 20), which underwent inoculation of 10 mL of 10(10) CFU/mL Escherichia coli R-6 confined to the small intestine as opposed to a BT1-14 group (n = 20), which underwent the BT procedure on days 1 and 14 or a S1-BT14 group (n = 20) that received 10 mL of saline on day 1 and the BT procedure on day 14. Half of the animals were killed 2 hours following the BT procedure. Samples from different compartments were collected for culture. Mesenteric lymph and peripheral blood were examined for WBC counts. The other half of the hosts was subjected to outcome evaluation concerning weight gain and mortality. Animals undergoing double BT showed a significantly lower index of bacterial recovery (liver, spleen, and blood) compared with those having a single BT (P < .05). The WBC count of mesenteric lymph cells after double BT was similar to naïve animals, but significantly lower than the single BT group (P < .05). The outcome was unchanged among double BT versus other groups. A previous BT challenge was efficient to generate a host-defense mechanism against a second BT episode induced by intestinal overgrowth with the same bacterial strain.

Bacterial Translocation, Microcirculation Injury and Sepsis

Sepsis is the result from a complex bacterial-host interaction, which is an often-fatal response when host protective molecular mechanisms designed to fight invading bacteria surpass the beneficial intensity to the point of causing injury to the host. Increasing evidences have implicated the bacterial translocation (BT) as the main source for the induction of sepsis, although the beneficial effect of BT process has been related to the development of the intestinal immune response by physiological interaction between bacteria and host. In this article, we examined evolving concepts concerning to BT and discussed about its potential role in the promotion of microcirculation injury, moreover, its possible participation in the sepsis induction. According to our data obtained from in-vivo BT animal-model, both bacterial overgrowth and bacterial pathogenic determinants seem to be major predisposing factors for the induction of BT. Besides, translocation of luminal bacteria through the lymphatic via elicits the activation of the GALT inflammatory response contributing to microcirculation injuries, and the haematological via of BT was responsible to the systemic bacterial spread. On other hand, the combination of BT process to the pre-existing host systemic infection played a crucial role in the worsening of the clinical outcome. In our understanding, studies concerning to intestinal immune response and the pathophysiology of bacterial-host interaction, under normal and disease conditions, seems to be the key elements to the development of therapeutic approaches towards sepsis.

Twenty-four-hour esophageal pH monitoring in children and adolescents with chronic and/or recurrent rhinosinusitis

Gastroesophageal reflux (GER) disorder was studied in children and adolescents with chronic and/or recurrent rhinosinusitis not associated with bronchial asthma. Ten children with a clinical and radiological diagnosis of chronic and/or recurrent rhinosinusitis, consecutively attended at the Pediatric Otolaryngology Outpatient Clinic, Federal University of São Paulo, were evaluated. Prolonged esophageal pH monitoring was used to investigate GER disorder. The mean age of the ten patients evaluated (eight males) was 7.4 +/- 2.4 years. Two patients presented vomiting as a clinical manifestation and one patient presented retrosternal pain with a burning sensation. Twenty-four-hour esophageal pH monitoring was performed using the Sandhill apparatus. An antimony probe electrode was placed in the lower third of the esophagus, confirmed by fluoroscopy and later by a chest X-ray. The parameters analyzed by esophageal pH monitoring included: total percent time of the presence of acid esophageal pH, i.e., pH below 4 (<4.2%); total number of acid episodes (<50 episodes); number of reflux episodes longer than 5 min (3 or less), and duration of the longest reflux episode (<9.2 min). One patient (1/10, 10%) presented a 24-h esophageal pH profile compatible with GER disorder. This data suggest that an association between chronic rhinosinusitis not associated with bronchial asthma and GER disorder may exist in children and adolescents, especially in those with compatible GER disorder symptoms. In these cases, 24-h esophageal pH monitoring should be performed before indicating surgery, since the present data suggest that 10% of chronic rhinosinusitis surgeries can be eliminated.

Evaluation of multiplex PCRs for diagnosis of infection with diarrheagenic Escherichia coli and Shigella spp

We have developed two multiplex PCR assays that detect typical and atypical enteropathogenic Escherichia coli (EPEC) isolates, enteroaggregative E. coli (EAEC) isolates, enterotoxigenic E. coli (ETEC) isolates, enteroinvasive E. coli (EIEC) isolates, Shiga toxin-producing E. coli (STEC) isolates, and Shigella spp. The targets selected for each group were eae and bfpA for EPEC isolates, the target of probe CVD432 for EAEC isolates, the genes encoding heat-labile and heat-stable toxins for ETEC isolates, stx(1) and stx(2) for STEC isolates, and ipaH for EIEC isolates and Shigella spp. These PCRs were specific and sensitive for rapid detection of target isolates in stools. Among 150 stool specimens from the acute diarrhea tested, 9 samples (6%) had atypical EPEC, 9 (6%) had typical EPEC, 7 (4.7%) had EAEC, 3 (2%) had EIEC, 3 (2%) had Shigella spp., and 1 (0.7%) had an O26 STEC strain; we also detected mixed infections, 2 (1.3%) with EAEC and Shigella spp., 1 (0.7%) with atypical and typical EPEC strains, and another with atypical EPEC and EAEC strains. One of the multiplex PCRs directly applied to 36 stool specimens correctly identified 100% of EPEC and EAEC isolates.

Dietary fiber, energy intake and nutritional status during the treatment of children with chronic constipation

The present prospective study was carried out to determine dietary fiber and energy intake and nutritional status of children during the treatment of chronic constipation. Twenty-five patients aged 2 to 12 years with chronic constipation were submitted to clinical evaluation, assessment of dietary patterns, and anthropometry before and after 45 and 90 days of treatment. The treatment of chronic constipation included rectal disimpaction, ingestion of mineral oil and diet therapy. The standardized diet prescribed consisted of regular food without a fiber supplement and met the nutrient requirements according to the recommended daily allowance. The fiber content was 9.0 to 11.9 g for patients aged less than 6 years and 12.0 to 18.0 g for patients older than 6 years. Sixteen patients completed the 90-day follow-up and all presented clinical improvement. The anthropometric variables did not change, except midarm circumference and triceps skinfold thickness which were significantly increased. Statistically significant increases were also found in percent calorie intake adequacy in terms of recommended daily allowance (55.5 to 76.5% on day 45 and to 68.5% on day 90; P = 0.047). Percent adequacy of minimum recommended daily intake of dietary fiber (age + 5 g) increased during treatment (from 46.8 to 52.8% on day 45 and to 56.3% on day 90; P = 0.009). Food and dietary fiber intake and triceps skinfold thickness increased during follow-up. We conclude that the therapeutic program provided a good clinical outcome.

Dietary cellulose has no effect on the regeneration of hemoglobin in growing rats with iron deficiency anemia

The objective of the present study was to determine the effect of cellulose on intestinal iron absorption in rats during recovery from iron deficiency anemia. Twenty-one-day-old male Wistar-EPM rats were fed an iron-free ration for two weeks to induce anemia. At 5 weeks of age, the rats were divided into two groups (both groups receiving 35 mg of elemental iron per kg diet): cellulose group (N = 12), receiving a diet containing 100 g of cellulose/kg and control (N = 12), receiving a diet containing no cellulose. The fresh weight of the feces collected over a 3-day period between the 15th and 18th day of dietary treatment was 10.7 +/- 3.5 g in the group receiving cellulose and 1.9 +/- 1.2 g in the control group (P<0.001). Total food intake was higher in the cellulose group (343.4 +/- 22.0 g) than in the control (322.1 +/- 13.1 g, P = 0.009) during the 3 weeks of dietary treatment. No significant difference was observed in weight gain (cellulose group = 132.8 +/- 19.2, control = 128.0 +/- 16.3 g), hemoglobin increment (cellulose group = 8.0 +/- 0.8, control = 8.0 +/- 1.0 g/dl), hemoglobin level (cellulose group = 12.3 +/- 1.2, control = 12.1 +/- 1.3 g/dl) or in hepatic iron levels (cellulose group = 333.6 +/- 112.4, control = 398.4 +/- 168.0 g/g dry tissue). We conclude that cellulose does not adversely affect the regeneration of hemoglobin, hepatic iron level or the growth of rats during recovery from iron deficiency anemia.

[Celiac disease: evaluation of compliance to gluten-free diet and knowledge of disease in patients registered at the Brazilian Celiac Association (ACA)]

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.

[Assessment of gliadin in pharmaceutical products - important information to the orientation of celiac disease patients]

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.

[Celiac disease: clinical characteristics and methods used in the diagnosis of patients registered at the Brazilian Celiac Association]

OBJECTIVE: To evaluate the clinical characteristics and methods used in the diagnosis of patients registered at the Brazilian Celiac Association (BCA). METHODS: A questionnaire about clinical characteristics and diagnostic methods in celiac disease was mailed to 584 members of the BCA. RESULTS: We received 292 responses for 584 questionnaires mailed (49.5%). The clinical characteristics of celiac disease in the sample we analyzed showed that the most frequent type was the classical mode (88.9%), while the atypical mode was present in only 11.1% of patients at the time of diagnosis. Increased incidence of both late diagnosed classical mode (44.5% to 64.2%; P=.004) and atypical mode (5.2% to 16.8%; P=.005) has been observed in the last 5 years. Duration of symptoms before diagnosis was greater than 1 year in 75% patients with atypical manifestation. Intestinal biopsy was not performed in 19% of the cases at the time of diagnosis. It was observed that in the last 5 years intestinal biopsy was not performed for a larger number of patients (24.4%) than in the previous period (only 11.1%) (P=.007). CONCLUSIONS: Classical mode is still the most frequent clinical manifestation of celiac disease. The late diagnosed classical mode is predominant, but our findings show an increase in the proportion of the atypical mode. Although characterization of subtotal or total villous atrophy of the intestinal mucosa is of paramount importance to the diagnosis of celiac disease, 19% of the patients diagnosed for celiac disease did not undergo intestinal biopsy at the time of diagnosis, most notably in the last 5 years.

Assessment of gliadin in supposedly gluten-free foods prepared and purchased by celiac patients

BACKGROUND

The present study was designed to evaluate the presence of gliadin in homemade foods prepared by patients with celiac disease and/or their relatives, as well as in processed products consumed by such patients in São Paulo, Brazil, by enzyme immunoassay (EIA) and Western blot (WB) analysis.

METHODS

One hundred ninety samples were analyzed: 108 homemade foods prepared in homes of patients with celiac disease, 81 processed products, and 1 positive control of homemade food. All samples were analyzed by EIA based on monoclonal antibodies to heat stable omega-gliadins and related prolamins from wheat, rye, and barley. Samples were also analyzed using the WB technique.

RESULTS

Only one (0.9%) of 108 homemade foods contained detectable amounts of gliadin, as determined by EIA. Twelve of 81 processed products contained gliadin by EIA, as follows: 5 of 61 without gluten listed in the ingredients, 2 of 11 malt extracts, 1 of 2 wheat starches, 1 of 2 types of beer, and all 3 positive control products. Gliadin content of these products was between 4 and 10 mg of gliadin/100 g of product, except for the wheat starch sample (28 mg of gliadin/100 g) and all 3 samples with gluten (>4000 mg of gliadin/100 g). The positive control of homemade food contained 152 mg of gliadin/100 g. One hundred three of 190 samples were analyzed by WB, and 21 of these were gliadin positive. A comparison of results obtained by EIA and WB showed no statistical differences between the methods.

CONCLUSIONS

The greater part of the foods prepared in homes of patients with celiac disease and most processed products supposed to be gluten-free did not contain gliadin. Therefore, celiac patients adequately prepare gluten-free homemade food and have the expertise to purchase processed gluten-free food in São Paulo, Brazil.

Studies of the small bowel surface by scanning electron microscopy in infants with persistent diarrhea

We describe the ultrastructural abnormalities of the small bowel surface in 16 infants with persistent diarrhea. The age range of the patients was 2 to 10 months, mean 4.8 months. All patients had diarrhea lasting 14 or more days. Bacterial overgrowth of the colonic microflora in the jejunal secretion, at concentrations above 10(4) colonies/ml, was present in 11 (68.7%) patients. The stool culture was positive for an enteropathogenic agent in 8 (50.0%) patients: for EPEC O111 in 2, EPEC O119 in 1, EAEC in 1, and Shigella flexneri in 1; mixed infections due to EPEC O111 and EAEC in 1 patient, EPEC O119 and EAEC in 1 and EPEC O55, EPEC O111, EAEC and Shigella sonnei in 1. Morphological abnormalities in the small bowel mucosa were observed in all 16 patients, varying in intensity from moderate 9 (56.3%) to severe 7 (43.7%). The scanning electron microscopic study of small bowel biopsies from these subjects showed several surface abnormalities. At low magnification (100X) most of the villi showed mild to moderate stunting, but on several occasions there was subtotal villus atrophy. At higher magnification (7,500X) photomicrographs showed derangement of the enterocytes; on several occasions the cell borders were not clearly defined and very often microvilli were decreased in number and height; in some areas there was a total disappearance of the microvilli. In half of the patients a mucus-fibrinoid pseudomembrane was seen partially coating the enterocytes, a finding that provides additional information on the pathophysiology of persistent diarrhea.

The gut at war: the consequences of enteropathogenic Escherichia coli infection as a factor of diarrhea and malnutrition

Diarrheal disease is still the most prevalent and important public health problem in developing countries, despite advances in knowledge, understanding, and management that have occurred over recent years. Diarrhea is the leading cause of death in children under 5 years of age. The impact of diarrheal diseases is more severe in the earliest periods of life, when taking into account both the numbers of episodes per year and hospital admission rates. This narrative review focuses on one of the major driving forces that attack the host, namely the enteropathogenic Escherichia coli (EPEC) and the consequences that generate malnutrition in an early phase of life. EPEC serotypes form dense microcolonies on the surface of tissue-culture cells in a pattern known as localized adherence (LA). When EPEC strains adhere to epithelial cells in vitro or in vivo they cause characteristic changes known as Attaching and Effacement (A/E) lesions. Surface abnormalities of the small intestinal mucosa shown by scanning electron microscopy in infants with persistent diarrhea, although non-specific, are intense enough to justify the severity of the clinical aspects displayed in a very young phase in life. Decrease in number and height of microvilli, blunting of borders of enterocytes, loss of the glycocalyx, shortening of villi and presence of a mucus pseudomembrane coating the mucosal surface were the abnormalities observed in the majority of patients. These ultrastructural derangements may be due to an association of the enteric enteropathogenic agent that triggers the diarrheic process and the onset of food intolerance responsible for perpetuation of diarrhea. An aggressive therapeutic approach based on appropriate nutritional support, especially the utilization of human milk and/or lactose-free protein hydrolyzate-based formulas and the adequate correction of the fecal losses, is required to allow complete recovery from the damage caused by this devastating enteropathogenic agent.

Measurement of low dietary fiber intake as a risk factor for chronic constipation in children

BACKGROUND

Scarce information exists regarding dietary fiber intake in children with chronic constipation. The objective of this case-control study was to evaluate the intake of fiber as a risk factor for chronic constipation.

METHODS

Fifty-two children with a mean age of 6.8+/-3.2 years who had chronic constipation were age and gender matched with 52 children with normal intestinal habits. The fiber content of the diet was evaluated with a 24-hour dietary recall. Two tables of fiber composition in foods were used: a Brazilian table, and a table based on the method of the Association of Official Agricultural Chemists (AOAC).

RESULTS

According to the Brazilian table, the median intake of fiber (in grams per day) by the constipated and the control groups was 13.8 and 17.3, respectively, for total fiber (p = 0.020), 6.8 and 9.7 for insoluble fiber (p = 0.004), and 6.5 and 7.6 for soluble fiber (p = 0.104). According to the AOAC table, the constipation group (9.7 g/day) also had lower (p = 0.0022) intake of total fiber than the control group (12.6 g/day). The coefficient of correlation between the two tables on fiber content of food was +0.82 (p < 0.001) in the constipation group and +0.86 (p < 0.001) in the control group. The intake of fiber was less than the minimum recommendation (age + 5 g) and statistically associated (p = 0.001) with the constipation group (75.0%) in comparison with the controls (42.5%). The odds ratio was 4.1 (95% confidence limits, 1.64-10.32).

CONCLUSION

Intake of fiber below the minimum recommendation is a risk factor for chronic constipation in children.

Acute diarrhea and malnutrition: lethality risk in hospitalized infants

OBJECTIVES

Acute diarrhea is a very frequent disease in developing countries and is the first cause of death in infants under two years of age. This study was designed to evaluate the clinical and epidemiological factors associated to the death of 17 out of 511 infants hospitalized due to severe acute diarrhea between January 1989 and December 1995.

PATIENTS AND METHODS

The patients were divided into two groups according to their clinical evolution: Group I--Death and Group II--Survival. The following parameters were evaluated: birth weight, gender, age, duration of diarrhea (days) prior to admission, nutritional status, hydration, presence of an enteropathogenic agent in the stools, food intolerance and duration of hospitalization.

RESULTS

The analyzed factors have shown a significant association with death for the following variables: age, relative factor of death (RFD)=4.0 for infants less than six months of age, identification of an enteropathogenic Escherichia coli (EPEC) strain in the stools (RFD=3.3), severe malnutrition at admission to the hospital (RFD=4.5), occurrence of food intolerance during hospitalization (RFD=2.7). Some enteropathogenic agent was identified in the stools of 253 infants (54.9%), among the 461 (90.2%) studied. Group I revealed the presence of an enteropathogenic agent in 75% of the cases. The most frequent agents identified in Group I were: EPEC (56.3%) and Shigella (12.5%), while in Group II EPEC was identified in 26.5% of the patients.

CONCLUSIONS

The association of some factors, such as age less than six months, severe malnutrition, food intolerance and the identification of EPEC strains in the stool culture, indicate a high risk of death in infants hospitalized due to severe acute diarrhea.

A localized adherence-like pattern as a second pattern of adherence of classic enteropathogenic Escherichia coli to HEp-2 cells that is associated with infantile diarrhea

Escherichia coli strains that cause nonbloody diarrhea in infants are known to present three distinct patterns of adherence to epithelial cells, namely, localized (LA), diffuse (DA), and aggregative (AA) adherence. Strains with LA (typical Enteropathogenic Escherichia coli [EPEC]) are well recognized as a cause of secretory diarrhea, but the role of strains with DA (DAEC) is controversial, and strains with AA (EAEC) have been more frequently related to persistent diarrhea whereas its relationship with acute diarrhea is not well defined. To determine the relationship of the different types of E. coli adherence patterns with acute diarrhea (lasting less than 14 days) and persistent diarrhea (lasting more than 14 days) in São Paulo, Brazil, we studied stool specimens from 40 infants under 1 year of age with diarrhea and 40 age-matched control infants without any gastrointestinal symptoms. Twenty-eight (35.0%) of eighty cases yielded adherent E. coli (HEp-2 cells). Strains with localized and aggregative adherence were associated with acute and persistent diarrhea. A total of 11.2% of the adherent strains were typical EPEC serotypes and hybridized with the enteroadherence factor probe; 5.0% were EAEC and hybridized with the EAEC probe. DAEC strains were isolated from 10.0% of patients and 7.5% of controls and did not hybridize with the two probes used (daaC and AIDA-I). Strains with a localized adherence-like pattern (atypical EPEC) were found significantly more frequently (P = 0.028) in cultures from children with diarrhea (17.5%) than in controls (2.5%).

Rotavirus subgroups, G serotypes, and electrophoretypes in cases of nosocomial infantile diarrhoea in Belém, Brazil

From November 1992 to November 1994 stool samples were obtained from 237 children admitted to a public hospital in Belém. Rotaviruses were detected in 19.3 per cent (60/310) of faecal samples. Of these, 32.1 per cent (18/56), 20.9 per cent (38/181), and 5.4 per cent (4/73) were recorded in cases of nosocomial diarrhoea, community-acquired diarrhoea, and controls, respectively. Fifty-two (86.7 per cent) of the 60 rotavirus-positive specimens were subgrouped and the G serotypes of 55 (91.7 per cent) of them were determined. Subgroups I and II were detected in 50 per cent each of the 52 subgrouped strains. G type 2 was present in 46 (83.6 per cent) of the 55 serotyped samples; serotypes G1 and (mixed) G1 and G4 were found in 14.5 per cent and 1.8 per cent, respectively, of these specimens. Viral RNA electrophoresis showed 14 distinct patterns, including 56.7 per cent (34/60) and 43.3 per cent (26/60) of long and short profiles, respectively. In 40 (66.6 per cent) of the 60 rotavirus-positive faecal samples no enteropathogens other than rotavirus were detected. There was an increased incidence of rotavirus infection from July 1993 to February 1994. The rotavirus-related episodes of diarrhoea were more severe than those of other aetiology and greater clinical severity was not related to a specific G type, subgroup, or electrophoretype.

[Association of patterns of Escherichia coli adherence to HEp-2 cells with acute and persistent diarrhea]

In Brazil diarrhea is the cause of approximately 15% of death among infants. Enteropathogenic E coli is the most important bacterial agent causing acute diarrhea, which is defined as less than 14 days of duration. About 30% of these cases may evolve to persistent diarrhea, defined as lasting more than 14 days. In this work it was carried out a case-control study including 34 children under 2 years of age, and admitted to hospital facilities in São Paulo for rehydration therapy. Thirty-four age matched children hospitalized in the same facilities, and presenting no gastrointestinal symptoms were included as controls. Stool samples were analyzed for the presence of bacterial pathogens (diarrheagenic E coli, Shigella, Salmonella, Yersinia, and Campylobacter), protoparasytes, rotavirus, and enteric adenovirus. The E coli strains isolated were analyzed for their ability to adhere to HEp-2 cultured cells, in a 3 h adhesion assay. Search for homology with DNA probes for localized adherence (EAF, eaeA probes), AA (enteroagregative adherence) (AA probe), and diffuse adherence (F1845, AIDA-I probes) was carried out by the colony hybridization method. Twenty-four of the cases were acute diarrhea and 10 persistent diarrhea. Strains with localized adherence were associated with acute and persistent diarrhea. About 23.5% of E coli were associated with typical Enteropathogenic E coli strains (EAF+, eaeA+). Enteroaggregative E coli (EAggEC) (AA+) was isolated only from cases and in similar frequency for acute and persistent diarrhea. Diffusely adherent E coli (DAEC) which did not hybridize with the diffuse adherence probes were isolated among cases and controls. E coli eaeA+ with localized-like adherence was isolated from cases in a frequency three times higher than in controls, suggesting that it may really have a pathogenic potential.

Nutritional management of regurgitation in infants

Infantile regurgitation is a frequently occurring problem. Throughout the world, anxious parents are imploring physicians to eliminate their infant's regurgitation. General practitioners, pediatricians and pediatric gastroenterologists strive to alleviate infantile regurgitation and its related parental stress. In this paper we define the scope of the problem and analyze the optimal, cost-efficient management approach to simple regurgitation in infants. The intent of this paper is to disseminate this information to practicing physicians and other health care professionals in an attempt to minimize the impact of this annoying problem of infancy and to eliminate confusion and expensive diagnostic tests and use of sub-optimal treatment modalities. Parental reassurance and dietary management by feeding thickened formula are important components in managing regurgitation in infants while maintaining optimal nutritional intake for adequate growth and development.

[Estimated dietary fiber intake in children according to different food composition reference tables]

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.

[Mortality in breast-fed infants with persistent diarrhea: risk factors associated with death]

OBJECTS

Persistent diarrhea is a frequent disease in developing countries. In this research, we studied 21 patients that passed away among 189 that were hospitalized with persistent diarrhea at the "Hospital Italo Brasileiro Umberto I Foundation", from January of 1985 until December of 1992.

PATIENTS AND METHODS

The patients were distributed into two groups: survival and dead, in accord of the clinical evolution at the end of the internment. The analyzed parameters were: birth weight, sex, age, provenance, diarrhea period before the admission, nutritional status, hydration status, coprologic results, occurrence of food intolerance, internment period and the age of ending breast-feeding.

RESULTS

The parameters that showed significantly association with the death were: age, with relative risk = 3 for children with age below 6 months old; provenance, with relative risk = 3.4 for patients who were arrived from other hospitals; third grade dehydration at the admission (relative risk = 2.9); enteropathogenic Escherichia coli (EPEC) isolated in feces (relative risk = 3.3), and use of total parenteral nutrition. The etiologic research was positive in 57.1% of the cases. The enteropathogen more frequently isolated in dead group, was EPEC (42.9%), followed by Shigella (9.5%) and Salmonella (5.9%). From the isolated EPEC (35/189), 26 (74.3%) were belonged to the OIII sorogroup (6/26). From these children, 23.1% died. From the 35 patients with EPEC isolated in feces, 25 were below 6 months old, and from these one, eight died. The relative risk to die for lactents with less than 6 months old and EPEC in feces was equal 3.2. Sepsis was considered the most important cause of death for hospitalized lactents with persistent diarrhea.

[Lactose intolerance in hospitalized infants with acute diarrhea due to classic enteropathogenic Escherichia coil (EPEC)]

Three hundred and eleven hospitalized weaned infants with acute diarrhea, all under 12 months of age, were studied in order to evaluate the development of lactose intolerance and its association with age, nutritional status, birth weight, dehydration and enteropathogenic agents identified in fecal samples. After been rehydrated the infants received whole cow' milk assuring the intake of 100 kcal/kg per day. Lactose intolerance was defined according t the following criteria: 1) persistence of diarrhea associated with weight loss during 48 hours, 2) development of vomiting and/or abdominal distention associated with excretion of carbohydrate in feces and/or acids tools, 3) metabolic acidosis associated with abdominal distention at anytime of refeeding period. Lactose intolerance was detected in 52.1% (162/311) of the patients and it was significantly associated with age under 6 months (P < 0.01), birth weight under 3000 grams (P < 0.01), development of dehydration (P < 0.01) and with enteropathogenic Escherichia coli (EPEC) serotypes infection (P < 0.01).

Morphometric study of the small bowel mucosa in infants with diarrhea due to enteropathogenic Escherichia coli strains

BACKGROUND/AIMS

Enteropathogenic Escherichia coli (EPEC) strains are the most important cause of gastroenteritis in infants under 1 year of age and may induce several patterns of villous atrophy in the intestinal mucosa. However, the interpretation of these abnormalities has usually been based on semiquantitative criteria, giving rise to considerably subjective results. We utilized the linear morphometry to analyze the morphological lesions of the small bowel mucosa induced by EPEC strains in infants with persistent diarrhea in comparison with those seen in infants with asymptomatic environmental enteropathy (AEE) and controls.

METHODOLOGY

Fifty nine specimens of small bowel mucosa were comparatively studied and divided in the following groups: 1. Group I: Thirty infants with persistent diarrhea due to EPEC strains, mean age 6.4 months; 2. Group II: Sixteen infants with AEE, mean age 6.5 months with no enteropathogenic bacteria in stools; 3. Group III: Thirteen children with short stature and no gastrointestinal complaints, mean age 15 months. Morphometric analysis of the small bowel mucosa was performed by using a x10 objective to a Zeiss light microscope, to which a measuring Zeiss ocular, t8x was adapted. The following measurements were carried out: Total mucosal thickness (TMT); Villous height (VH); Crypt length (CL); Intraepithelial lymphocyte (IEL) count.

RESULTS

Except for the IEL, there was a significant difference in all the parameters analyzed among the evaluated groups. Group I revealed the lowest values for total mucosal thickness, villous height, and the ratio villous height/crypt length in comparison with the two other groups. On the other hand, the crypt length measurements for Group II were larger than those for Groups I and III. The measurements of villous height and the ratio villous height/crypt length for Group III turned out to be greater than those for Group II.

CONCLUSIONS

The utilization of an accurate technique in the morphological study of the small bowel mucosa allowed us to detect severe abnormalities not only in infants with EPEC infection, but also in those counterparts who live in contaminated environments, and can therefore potentially acquire this type of intestinal infection.

[Acute diarrhea: stool water loss in hospitalized infants and its correlation with etiologic agents and lactose content in the diet]

Forty weaned male infants were studied during their first year of life, all hospitalized with acute diarrhea in the Gastroenterology and Metabolism Unit of the Hospital "Umberto I", São Paulo, SP, Brazil. We evaluated and quantified water fecal losses, employing the metabolic bed technique, relating the feeding formula employed with the different causal enteropathogenic agents. 67.5% of the studied infants were under six months and 40% under three months of age. Two groups were randomly assembled to receive, lactose or lactose free feeding formulae. Twenty one patients received a lactose-containing formula (Ninho 10%) and the other 19 children were fed caseine (Portagen) formulae. According to coproculture results and identification of enteropathogenic agents, we divided the studied infants relating feeding formula with the presence or absence of the enteropathogenic Escherichia coli (EPEC): I-13 with positive coproculture for EPEC and diets which included lactose--(L/EPEC+); II--eight with negative coproculture for EPEC and diets which included lactose--(L/EPEC-); III--seven with positive coproculture for EPEC and lactose free diets--(G/EPEC+); IV--12 with negative coproculture for EPEC and lactose free diets. (G/EPEC-). The most frequently isolated agent at coproculture was EPEC, in 20 of the cases (50%), followed by Campylobacter (7.5%). It was also possible to observe that the frequencies of EIEC, Salmonella and Rotavirus were all equal (2.5%). Mixed infections occurred only between EPEC and EIEC, registering a frequency of 5%. The EIEC samples, associated to EPEC 0111 were serotyped as 0 28 ac: H- and 0 152:H-. The use of metabolic bed made the evaluation of fecal volumes possible by a simple and quick technique, thus allowing a closer clinical monitoring, as well as a more reliable evaluation of the patients hospitalized with acute diarrhea. Average acceptance volumes of the formulae--either with or without lactose--were always below the amount recommended by FAO/WHO (100 kcal/day) which shows the impact of acute diarrhea on the decrease of food intake. The average volumes of watery fecal losses found among any of the studied subgroups may be considered quite relevant when compared to standard values. Especially within the L/EPEC+ group fecal losses, both on the first day (83.56 ml/kg/day) and, mainly, on the second (119.44 ml/kg/day) reached exceedingly high levels indicating a disastrous association between the presence of EPEC in the small intestine and lactose offer in the diet. Thus, the results show that there exists a positive and significant association between poor lactose absorption and the presence of EPEC in the feces. WHO's recommendation proposing the use of diluted cow milk, in universal and indiscriminate administration, in the two first days of the disease, may represent a risk factor, not only for malnutrition, but also for the survival rates of children with severe diarrhea, especially those under six months of age and hospitalized with EPEC enteroinfection.

[Scanning electronic microscopy of the small intestine in persistent diarrhea]

Persistent diarrhea very often leads children to malnutrition. It has become the major cause of death resulting from acute diarrhea episodes in developing countries. In order to determine the ultrastructural alterations of the small bowel that occur in the syndrome, 16 infants with severe persistent diarrhea were studied, utilizing light microscopy and the scanning electron microscope. Stool and jejunal fluid samples were collected for culture, rotavirus, ova and parasite search. Enteropathogenic agents were isolated in stools from 11 (68.7%) patients and bacterial proliferation in the small bowel was detected in 11 (68.7%) patients. EPEC strains were the most frequent enteropathogenic agent isolated both from stool and jejunal fluid cultures. The stool cultures revealed the presence of the following enteropathogenic microorganisms: EPEC 0111 in four, EPEC 0119 in one, EAggEC in five, Shigella flexneri in two, and Shigella sonnei in one; mixed infections due to EAggEC associated with EPEC 0111 were seen in two patients. The light microscopic analysis revealed that 56.2% of the patients suffered moderate villous atrophy most frequently associated with effacement of the microvilli, intracytoplasmatic vacuolization, increased number of multivesicular bodied and increased lymphocytic and eosinophylic infiltration in the lamina propria. The scanning electron microscopic analysis revealed in all cases shortening of the villi and enterocyte derangements; very often there was a total lack and/or effacement of the microvilli; in half of the patients there was a mucoid material covering the enterocytes tightly adhered to the apical epithelium surface. The scanning ultrastructural alterations observed in these patients are probably due to an association of factors brought about by the presence of enteropathogenic microorganisms and the resulting food intolerance that is responsible for perpetuation of diarrhea.

[Classic enteropathogenic Escherichia coli]

Enteropathogenic Escherichia coli. (EPEC) are gram negative bacteria of great importance in the etiology of diarrhea in children under two years of age living in developing countries. It was first reported in 1946. Its pathogenic mechanism was unknown until 1970 when several papers were published in the attempt to find out their physiophatologic mechanism. These bacteria interfere on the small bowel resulting in parcial or sub total villous atrophy. This injury will revert when the infection subsides.

Attaching and effacing enteropathogenic Escherichia coli O18ab invades epithelial cells and causes persistent diarrhea

A case of persistent diarrhea following Escherichia coli O18ab gastroenteritis is reported. Electron microscopy of a biopsy of the small intestine showed effacement of the brush border, attachment of bacteria to the epithelial cells with pedestal formation, and bacteria within the enterocytes. The bacterial isolate was an enteropathogenic E. coli isolate which did not contain the adherence factor (EAF) but possessed the attaching-effacing eae gene, was able to invade HeLa cells in a gentamicin invasion assay, and also invaded rabbit intestinal cells. Results suggest that E. coli organisms of the O18ab serotype may cause diarrhea by an as yet unknown pathogenic mechanism, involving attaching to and effacing of enterocytes followed by invasion of the epithelial cells.

[Intake of dietary fiber and other nutrients by children with and without functional chronic constipation]

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.

Nutritional impact and ultrastructural intestinal alterations in severe infections due to enteropathogenic Escherichia coli strains in infants

OBJECTIVE

Enteropathogenic Escherichia coli (EPEC) strains are able to adhere to human intestinal tissue inducing a typical lesion causing dissolution of the brush border membrane and loss of microvillus structure at sites of bacterial attachment. The presence of these lesions can provoke perpetuation of diarrhea associated with malabsorption of the nutrients and nutritional aggravation. In this paper we report the nutritional impact of severe EPEC gastroenteritis in infants in a small bowel ultrastructural study.

METHODS AND RESULTS

Two infants aged 3 months and one 4 month old infant with profuse watery diarrhea lasting less than 6 days were studied. After rehydration therapy, the patients were fed a cow's milk formula and since food intolerance was diagnosed, a protein-hydrolisate, lactose-free formula was introduced. This dietary modification was successful, diarrhea ceased, the patients were discharged and followed up for 30 days. The following EPEC strains were identified in the stools and in the jejunal secretion: O111ab:H2, O119:H6 and O18ab:H14. A small bowel biopsy was performed and the electron microscopic study revealed bacteria tightly adhered to the apical portion of the enterocyte and effacement of the microvilli. These lesions were more prominent in the areas where bacteria were present.

CONCLUSION

The patients underwent an acute nutritional aggravation due to food intolerance, but the introduction of a protein-hydrolisate, lactose-free formula, allowed prompt cessation of diarrhea and nutritional recovery.

[Hydrogen test (H2) in the air expired for the diagnosis of small bowel bacterial overgrowth]

The small bowel bacterial overgrowth is characterized by the presence of colonic flora in the small bowel, may to lead malabsorption and/or diarrhea and/or weight loss. The small-bowel culture has served as the "gold standard" for diagnosing bacterial overgrowth. The colonic flora is able to ferment carbohydrates that are present in the lumen of the intestinal tract with production of hydrogen, which is subsequently observed and excreted by the breath. Therefore, the hydrogen breath test after oral carbohydrates administration represents an alternative, non-invasive and specific method for diagnosing small bowel bacterial overgrowth.

Ultrastructural study of enteropathogenic Escherichia coli O111ab:H2 infection in an infant with acute diarrhea

Enteropathogenic Escherichia coli is the most important cause of acute diarrhea in developing countries, specially in infants under one year of age. Enteropathogenic Escherichia coli strains are able to induce profound cytoskeletal alterations in the enterocyte known as attaching and effacing lesions, associated with the formation of cuplike pedestals. We report an Enteropathogenic Escherichia coli O11ab:H2 strain isolated from an infant with acute diarrhea, on the eleventh day of disease, that caused attaching and effacing lesion and penetrated the enterocyte, as well as invaded the HeLa cell tissue culture in vitro and the rabbit ileal loop assay in vivo, in the ultrastructural study. This observation indicates that the severe lesions of the small bowel caused by an enteropathogenic Escherichia coli O111ab:H2 strain can occur even in the early stages of the infection.