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Objectives: Clostridium difficile caused nearly 500,000 infections and was associated with approximately 29,000 deaths in 2011, according to data from the Centers for Disease Control and Prevention. C. difficile is a bacterium that causes diarrhea and, often, severe illness in healthcare facilities, as well as the community. Our objective was to determine whether alkaline colonic pH predisposes to colonization and infection with C. difficile., Methods: A total of 228 patients with diarrhea and/or abdominal pain, leukocytosis, and fever were included. Stool pH was measured, and C. difficile antigen and toxin in stool were detected., Results: Of 228 patients, 30 (13.2%) tested positive for C. difficile (antigen+/toxin+) and 171 (75%) were C. difficile negative (antigen-/toxin-). Of 171 patients who tested negative, 93 (54.4%) had stool pH >7.0 and 78 (45.6%) had pH ≤7.0. Among the 30 patients who tested positive, 26 (86.7%) had stool pH >7.0 (P = 0.002). Among the 27 colonized patients (antigen+/toxin-), 12 (44.4%) had stool pH >7.0 (P = 0.34). For all patients with stool pH ≤7.0, 96% tested negative for C. difficile infection (P = 0.002)., Conclusions: A strong association between C. difficile infection and alkaline stool pH was found.

The main aim of this study was to investigate the effect of different coating materials (i.e. Na-alginate and chitosan) on the viability and release behavior of Bifidobacterium pseudocatenulatum G4 in the simulated gastric fluid (SGF) and simulated intestinal fluid (SIF). This study reports the viability of encapsulated B. pseudocatenulatum G4 coated using different alginate (2-4 g/100mL) and chitosan (0.2-0.8 g/100mL) concentrations. The results indicated that the highest concentration of alginate (4.4142 g/100mL) along with 0.5578 g/100mL chitosan resulted in the highest viability of B. pseudocatenulatum G4. The release behavior of the encapsulated probiotics in SGF (pH 1.5) in 2h followed by 4h in SIF (pH 7.4) was also assessed. The resistance rate of alginate-chitosan capsule in SGF was higher than SIF. The alginate-chitosan encapsulated cells had also more resistance than alginate capsules. The current study revealed that alginate encapsulated B. Pseudocatenulatum G4 exhibited longer survival than its free cells (control)., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Two HPLC methods with diode array detection (HPLC-DAD) and electrospray ionization-mass spectrometry (HPLC-ESI/MS), respectively, were developed to investigate the differences of chemical constituents and their metabolism in gastrointestinal tract in vitro between two decoctions of crude and processed Glycyrrhizae radix. Total of eleven constituents (liquiritin apioside, liquiritin, licuraside, isoliquiritin, ononin, glycyrrhizin, liquiritigenin-7,4'-diglucoside, licorice saponin A3, 22β-acetoxylglycyrrhizic acid, licorice saponin G2, and yunganoside E2) were identified in the two decoctions, whereas lower contents of these constituents were usually found in the decoction of processed Glycyrrhizae Radix. [corrected] Furthermore, these constituents were metabolized into their respective aglycons in human intestinal bacteria juice, and the metabolism ratios were all higher in processed Glycyrrhizae Radix [corrected] decoction. No change was found in artificial gastric or intestinal juice. This study revealed that the processing can alter the contents of main constituents in crude G. radix and their metabolism in gastrointestinal tract, in which intestinal bacteria play an important role in the metabolism of licorice constituents.

The human gut harbours a large and genetically diverse population of symbiotic microbes that both feed and protect the host. Evolutionary theory, however, predicts that such genetic diversity can destabilise mutualistic partnerships. How then can the mutualism of the human microbiota be explained? Here we develop an individual-based model of host-associated microbial communities. We first demonstrate the fundamental problem faced by a host: The presence of a genetically diverse microbiota leads to the dominance of the fastest growing microbes instead of the microbes that are most beneficial to the host. We next investigate the potential for host secretions to influence the microbiota. This reveals that the epithelium-microbiota interface acts as a selectivity amplifier: Modest amounts of moderately selective epithelial secretions cause a complete shift in the strains growing at the epithelial surface. This occurs because of the physical structure of the epithelium-microbiota interface: Epithelial secretions have effects that permeate upwards through the whole microbial community, while lumen compounds preferentially affect cells that are soon to slough off. Finally, our model predicts that while antimicrobial secretion can promote host epithelial selection, epithelial nutrient secretion will often be key to host selection. Our findings are consistent with a growing number of empirical papers that indicate an influence of host factors upon microbiota, including growth-promoting glycoconjugates. We argue that host selection is likely to be a key mechanism in the stabilisation of the mutualism between a host and its microbiota., Competing Interests: The authors have declared that no competing interests exist.

A novel Bacillus subtilis KD1 strain was isolated and identified from healthy broilers, and its phylogenetic classification was subsequently analyzed. To evaluate its probiotic availability, its growth characteristics and tolerance for the gut environment were evaluated in vitro. The results suggest that B. subtilis KD1 is superior in secreting neutral protease and is highly tolerant of gastric acid and bile salt. In the logarithmic growth phase, the neutral protease reached a maximum of 1,369.3 U/mL. When all live bacteria had become spores in the broth, B. subtilis KD1 was freeze dried and fed to broilers at 10(9), 5 × 10(9), and 10(10) bacilli/kg of feed. The animal trial results suggest that the addition of the new strain significantly improved intestinal flora by increasing lactobacilli and reducing Escherichia coli (P < 0.05) as compared with the control; hence, B. subtilis KD1 is a promising probiotic organism in broilers.

On contact with the mucosa, heat stable (STa) enterotoxin from Escherichia coli reduces fluid absorption in vivo in the perfused jejunum of the anaesthetized rat. The question of whether it also has a vagally mediated remote action on jejunal absorption, when instilled into the ileum, was re-examined, given contradictory findings in the literature. A standard perfused loop preparation was used to measure luminal uptake of fluid in vivo by means of volume recovery. STa in the ileum was found to have no effect on jejunal absorption, regardless of cervical or sub-diaphragmatic vagotomy and also regardless of the nature of the perfusate anion. The batches of toxin were shown in parallel experiments to reduce fluid absorption directly in the jejunum and also in the ileum. Similarly, vagal nerves prior to section had demonstrable in vivo physiological function. There was therefore no evidence for an indirect, vagally mediated ileal effect of STa on proximal fluid absorption.

Background: Dysgonomonas species were first designated in 2000. However, clinical infections due to this microorganism have rarely been described. Our aim was to present the first isolation of Dysgonomonas mossii from intestinal juice of a patient with pancreatic cancer., Methods: Predominantly appearing grayish-white colonies grown on chocolate and sheep blood agar plates were characterized morphologically by Gram stain, biochemically by automated instrument using Vitek II ID-GNB card together with commercially available kit systems, ID-Test HN-20 and API rapid ID 32A32A, and genetically by sequencing the 16S rRNA gene of the organism using a Taq DyeDeoxy Terminator Cycle Sequencing and a model 3100 DNA sequencer instrument. The isolate was further characterized by antimicrobial susceptibility using MicroFast 4J Panels and additional biochemical and physiological properties., Results: The isolate was finally identified as D. mossii from the findings of the morphological, cultural, and biochemical properties together with the comparative sequence of the 16S rRNA genes. The isolate was highly susceptible to many antibiotics but resistant to penicillins and cephems., Conclusions: As D. mossii was rarely encountered in the clinical microbiology laboratory, it may be misidentified as an X-factor-dependent Haemophilus species due to its negative result for the porphyrin test. Accumulation of the case reports with the isolation of this species is expected to elucidate the infections due to D. mossii. The presence of D. mossii caused no significant clinical infection despite repeated isolations, as the patient had no conspicuous abdominal complaints. However, our report is a noteworthy and useful piece of information.

Aim: This study evaluated the production of colanic acid (CA) exopolysaccharide (EPS) by Escherichia coli O157:H7 in relation to the pathogen's ability to survive under acidic conditions simulating the environment in the human gastrointestinal tract., Methods and Results: Escherichia coli O157:H7 W6-13 and its CA-deficient mutant M4020 were examined for their resistance to bile salts, and their ability to survive in simulated gastric fluid containing pepsin (pH 2.0) and simulated intestinal fluid containing pancreatin (pH 8.0). The effect of acid adaptation at pH 5.5 on the survival of E. coli O157:H7 in simulated gastric fluid was also determined. The results indicated that the survivability of M4020, under conditions simulating the environment in the human gastrointestinal tract, reduced more drastically than the viability of W6-13. The presence of bile salts had a slight effect on both types of E. coli O157:H7 cells. The loss of CA did not change the ability of M4020 to respond to acid adaptation., Conclusion: The EPS CA may serve as a protective barrier to E. coli O157:H7 for its survival in the human gastrointestinal tract., Significance and Impact of the Study: The study contributes to a better understanding of the EPS affecting the ability of E. coli O157:H7 to combat acid stress.

Objectives: In human immunodeficiency virus (HIV)-infected patients with chronic unexplained diarrhea, upper endoscopy with small bowel biopsy and aspirate is often performed to identify treatable pathogens. The purpose of this study was to compare the diagnostic yield of duodenal with jejunal biopsy and aspirate., Methods: All HIV-infected patients with chronic unexplained diarrhea who were evaluated by upper endoscopy at Bellevue Hospital Center between January 1992 and January 1997 were identified. Data were collected by reviewing patient charts, endoscopy reports, and pathology records., Results: During the 5-yr study period, 442 patients underwent upper endoscopy with sampling of the duodenum (N=173) or jejunum (N=269). A pathogen was identified in 123 patients (27.8%). Microsporidia was the most common organism detected (12.2%). The diagnostic yield of jejunal biopsy and aspirate was significantly higher than that obtained from the duodenum (32.3% vs 20.8%, p=0.009). Small bowel aspirates detected a pathogen in only 1.8% of patients evaluated, and there was no difference in the yield of duodenal and jejunal aspirates (1.3% vs 2.1%, p=0.7). Patients with a CD4 count of < 100 cells/mm3 were significantly more likely to have a pathogen identified than those with higher CD4 counts (38.8% vs 7.1%,p < 0.0001)., Conclusions: Upper endoscopy with small bowel biopsy and aspirate identifies a pathogen in 27.8% of individuals with HIV-related chronic unexplained diarrhea. In this patient population, jejunal biopsies acquired by enteroscopy are superior to those obtained from the duodenum. Small bowel aspirates are of little value in the workup of chronic HIV-related diarrhea.

The yeast strains Saccharomyces cerevisiae CBS 7764 and Debaryomyces hansenii Hf1 (CBS 8339), isolated from the intestine of rainbow trout, were studied with respect to adhesion to and growth in fish intestinal mucus. The level of adhesion was dependent on the physiologic state of the yeast culture. Growing cells of both strains adhered more strongly than nongrowing cells. This correlates with a previously shown shift in cell surface hydrophobicity of these yeasts. In addition, forces other than hydrophobic interactions may participate, as all strains tested adhered more strongly to the membrane lipid phosphatidylserine than to phosphatidylcholine and phosphatidylethanolamine. Debaryomyces hansenii Hf1 also adhered to the most hydrophobic of the neutral lipids present in mucus, while no adhesion was observed to the other neutral lipids or to the hydrophilic silica gel, again suggesting hydrophobic interactions. Finally, the fish-isolated yeasts grew rapidly in isolated fish intestinal mucus as the sole source of energy and nutrients.

The aim of the study was to determine whether the specificity of the [14C]d-xylose breath test could be improved, by excluding false-positive tests due to premature colonic metabolism of the [14C]d-xylose caused by rapid colonic transit. Forty-seven patients with suspected small bowel bacterial overgrowth were investigated by (1) aspiration and culture of duodenal fluid and (2) a [14C]d-xylose breath test. Those with either a positive duodenal culture or breath test had a repeat [14C]d-xylose breath test given with one of three transit markers (barium, Gastrografin or 99mTc-labeled tin colloid) to determine if the site of metabolism was in the small bowel or colon. Fourteen patients had positive duodenal cultures, four of whom had a negative [14C]d-xylose breath test, 15 patients had a positive [14C]d-xylose breath test, three of which were due to colonic metabolism of the xylose. Where transit markers were used, 14C was detectable in the breath and serum before barium had entered the small bowel, thus the barium did not comigrate with the xylose. Gastrografin accelerated small bowel transit, leading to malabsorption of the xylose in the small intestine and subsequent colonic metabolism of the xylose. 99mTc-labeled tin colloid had no obvious disadvantages and appeared to be the marker of choice. The use of a transit marker increased the specificity of the [14C]d-xylose breath test from 85% to 94%. The specificity of the [14C]d-xylose breath test for the detection of small bowel bacterial overgrowth is improved to greater than 90% by the use of an appropriate transit marker.

It is unknown whether bacteriolysis due to luminal complement activation contributes to local defense mechanisms against small intestinal bacterial overgrowth, particularly with gram-negative bacteria. This study addressed this issue. Thirty adult subjects were investigated with culture of luminal secretions adherent to proximal small intestinal mucosa. Luminal and plasma concentrations of C3 and C3d and C3d/C3 ratios were determined. Activated terminal complement complex was sought in surface epithelium to which aspirated secretions had been adherent. Small intestinal bacterial overgrowth with gram-negative bacteria was present in 12/30 (40.0%) subjects. C3, C3d, and C3d/C3 profile indicated that increased local but not systemic C3 activation occurs in this group. Conversely, no activation of terminal complement complex was evident in this circumstance. Thus, complement-mediated bacteriolysis is unlike to contribute to local defense mechanisms against small intestinal bacterial overgrowth, even when overgrowth flora includes gram-negative bacteria. Factors preventing full local activation of the complement cascade in this circumstance require investigation.

Background: The influence of luminal bacteria on small-intestinal permeability has not been fully assessed. This study addressed this issue., Methods: Thirty-four subjects (mean age 64 years; range 22-95 years) were investigated for possible small-intestinal bacterial overgrowth (SIBO) with culture of a small-intestinal aspirate. A lactulose/mannitol small-intestinal permeability test was performed, small-intestinal histology assessed and serum vitamin B12 concentrations measured in all subjects. Permeability was also assessed in a control group of 34 asymptomatic volunteers., Results: Urinary lactulose/mannitol ratios were significantly increased in subjects with SIBO with colonic-type flora (P < 0.0005), even in the absence of villous atrophy. Urinary lactulose/mannitol ratios were increased in this group due to significantly increased urinary lactulose concentrations (P < 0.0005) rather than reduced urinary mannitol levels, after correcting for inter-subject variations in renal function. Counts of intraepithelial lymphocytes of CD8 phenotype were significantly increased in this group (P = 0.003). Although a significant correlation was found between intraepithelial lymphocyte counts and small-intestinal permeability overall (P < 0.002), these counts were not significantly different in subjects with SIBO with colonic-type flora whose permeability values were < or = > 0.028, the upper limit of normal in asymptomatic controls. Serum vitamin B12 concentrations did not differ significantly between groups (P > 0.5). Ageing did not independently influence small-intestinal permeability (P > 0.5)., Conclusions: Small-intestinal permeability is increased in subjects with SIBO with colonic-type bacteria. This effect is independent of ageing and not mediated by vitamin B12 deficiency. Although counts of intraepithelial lymphocytes of CD8 phenotype are increased in this disorder, it is also unlikely that these cells play an important causative role in this process. Routine light microscopic assessment underestimates the prevalence of small-intestinal functional disturbance in this disorder.

Objectives: To evaluate the diagnostic yield of performing duodenal biopsies and aspirates in AIDS patients with chronic diarrhea., Methods: Retrospective review of esophagogastroduodenoscopy (EGD) records from January 1993 to March 1995 to identify those patients who underwent EGD for evaluation of AIDS associated diarrhea and had a duodenal biopsy and/or aspirate. Biopsies were examined for pathogens using routine histology and special stains, viral culture, and electron microscopy. Duodenal aspirates were evaluated for ova and parasites. All patients had previous negative stool studies. Pathology laboratory charges (hospital and professional fees) for each test and charges per positive test were determined., Results: Of the 57 patients included in this study, 56 had a duodenal biopsy and 42 had a duodenal aspirate. An established pathogen was identified in only 15 (26%) patients. One patient had both Mycobacterium avium complex and microsporidia. Pathogens were identified in seven patients by hematoxylin and eosin stain, in three patients by acid-fast bacillus stain, and in six patients by electron microscopy. No pathogens were identified with Gomori's methenamine silver stain (44 patients), duodenal aspirate for ova and parasites (46 patients), immunoperoxidase stains (4 patients), or viral culture (4 patients). Cryptosporidia were identified in six, microsporidia in five, Mycobacterium avium complex in three, and Giardia lamblia and adenovirus each in one patient., Conclusions: In this series, the diagnostic yield of EGD with duodenal biopsy and aspirate in AIDS associated diarrhea was low. Pathogens were identified in 26% of patients; predominantly Cryptosporidium organisms and microsporidia. The routine performance of aspiration of duodenal contents for parasite examination and staining of duodenal tissue with Gomori's methenamine silver stain for fungal identification are not recommended. One should consider obtaining tissue for electron microscopy whenever duodenal biopsies are performed. The utility of EGD in AIDS associated diarrhea may improve as more effective therapies become available.

Objective: Small intestinal hypomotility is an important cause of small intestinal bacterial overgrowth, yet assessment of small intestinal motility in this setting is problematic. This study was performed to investigate the validity of a bacteriological method for detecting small intestinal hypomotility., Methods: Twenty-five subjects without previous gastric surgery were studied with (i) concurrent bacteriological analyses of fasting saliva and gastric and proximal small intestinal aspirates, (ii) measurement of gastric pH, and (iii) scintigraphic assessment of small intestinal transit rates of a liquid test meal. The reproducibility of bacteriological analyses of saliva and small intestinal secretions was determined in 12 subjects., Results: Serial bacteriological analyses of saliva and proximal small intestinal secretions yielded reproducible results over time periods of up to 1 month. Eleven subjects were deemed to harbor Enterobacteriaceae of nonsalivary origin in proximal small intestinal secretions. Orocaecal transit, but not gastric emptying, of a liquid test meal was significantly delayed in this group (p = 0.002 and p = 0.84, respectively), suggesting the presence of small intestinal hypomotility. Impaired gastric acidity unlikely confounded assessment of the origin of small intestinal Enterobacteriaceae in any instance., Conclusions: The presence of Enterobacteriaceae of nonsalivary origin in proximal small intestinal secretions may be taken to reflect the presence of small intestinal hypomotility. The presence of impaired gastric acidity does not confound this approach. Because small intestinal intubation and culture of aspirate are required anyway to accurately diagnose small intestinal bacterial overgrowth, the simple addition of concurrent bacteriological analysis of saliva may allow small intestinal hypomotility to be detected at the same time as the presence or absence of small intestinal bacterial overgrowth itself is established, thus streamlining the investigation of subjects for this disorder and its possible causes.

Background: Urinary oxalate may contribute far more than urinary calcium to the pathogenesis of urinary calculi. Urinary oxalate may be reduced by restricting the intake of foods high in oxalate. The oxalate content foods might be reduced by oxalate-degrading bacteria. The purpose of this experiment was to reduce the oxalate content of foods with an oxalate-degrading bacterium which was isolated from the feces of Japanese male., Methods: An artificial intestinal juice was prepared by modifying Rogosa medium. An infusion of black tea was prepared from a commercial tea bag. The oxalate-degrading bacteria used were Eubacterium lentum WYH-1 which were have isolated. To 5 ml of the above oxalate-containing artificial intestinal juice and infusion of black tea, 0.5 ml of the bacterial culture was added and incubated anaerobically at 37 degrees C. Oxalic acid in the supernatant of the culture medium was assayed by high-performance liquid chromatography., Results: In 24 hours, 1 x 10(6) cells/ml of Eubacterium lentum WYH-1 decomposed 100% of 1 mg/ml oxalate in the artificial intestinal juice. The oxalate in the black tea infusion (1 mg/mL) was also decomposed completely within 48 hours by 1 x 10(7) cells/mL of bacteria., Conclusion: Eubacterium lentum WYH-1 was able to efficiently decompose the oxalate in foods.

The efficacy of a string test for the detection of small bowel bacterial overgrowth (SBBO) was determined by comparison with a sterile endoscopic method for sampling small bowel secretions in 15 subjects investigated for SBBO. Clinical value was found to be limited by poor sensitivity, specificity and positive predictive value. The string test is not an adequate substitute for oro-duodenal intubation for the detection of SBBO.

The extent of duodenal bacterial overgrowth during the pronounced inhibition of acid secretion that occurs with omeprazole treatment is unknown. The bacterial content of duodenal juice of patients treated with omeprazole was therefore examined in a controlled prospective study. Duodenal juice was obtained under sterile conditions during diagnostic upper endoscopy. Aspirates were plated quantitatively for anaerobic and aerobic organisms. Twenty five outpatients with peptic ulcer disease were investigated after a 5.7 (0.5) weeks (mean (SEM)) treatment course with 20 mg (nine patients) or 40 mg (16 patients). The control group consisted of 15 outpatients referred for diagnostic endoscopy without prior antisecretory treatment. No patient in the control group had duodenal bacterial overgrowth. In the omeprazole group bacterial overgrowth (> or = 10(5) cfu/ml) was found in 14 (56%) patients (p = 0.0003). The number of bacteria (log10) in duodenal juice in patients treated with omeprazole was distinctly higher (median 5.7; range < 2-8.7) when compared with the control group (median < 2; range < 2-5.0; p = 0.0004). As well as orally derived bacteria, faecal type bacteria were found in seven of 14 and anaerobic bacteria in three of 14 patients. Bacterial overgrowth was similar with the two doses of omeprazole. These results indicate that duodenal bacterial overgrowth of both oral and faecal type bacteria occurs often in ambulatory patients treated with omeprazole. Further studies are needed to determine the clinical significance of these findings, particularly in high risk groups during long term treatment with omeprazole.

Epidemics of cholera caused by Vibrio cholerae O1 occur regularly in Bangladesh, but until lately V cholerae non-O1 has been associated only with sporadic cases of diarrhoeal disease in many parts of the world, including Bangladesh. We describe a large epidemic of cholera-like disease in Bangladesh that is due to a V cholerae non-O1. The epidemic began in December, 1992, in southern Bangladesh and spread throughout the country. By the end of March 107,297 cases of diarrhoea and 1473 deaths had been reported. The disease is indistinguishable from cholera in clinical features and response to treatment, but most of the cases are in adults, which suggests that the population has no previous immunological experience of the organism. At two centres 375 (40%) of 938 and 236 (48%) of 492 rectal swabs were positive for V cholerae non-O1, as were 5 of 54 surface water samples. 55 isolates of V cholerae non-O1 were studied in detail. They resembled El Tor vibrios in being resistant to polymyxin B and positive for agglutination of chicken erythrocytes. The strain did not belong to any of the 138 known V cholerae serogroups; so a new serogroup O139, with the suggested name Bengal, is proposed. All the isolates studied produced large amounts of an enterotoxin apparently identical to cholera toxin. This strain seems to have pandemic potential. It is important that other countries in southeast Asia are aware of the strain's potential to cause severe morbidity and mortality.

A 28-year-old woman complained of chronic diarrhoea of about one year's duration, made worse by taking food. As a lactose tolerance test showed evidence of severe intolerance she was given a lactose-free diet, but this brought no improvement. Duodenal biopsy showed villous atrophy, and in the duodenal juice there were numerous flagellated lamblia. After a single oral dose of 2 g tinidazole the diarrhoea stopped, the lamblia disappeared, and the lactose intolerance and villous atrophy cleared up. Lamblia were also detected in the duodenal juice of a 50-year-old woman, but her infection was much more difficult to treat. Tinidazole (single dose of 2 g), metronidazole (800 mg twice daily for 6 days), ornidazole orally 500 mg twice daily for 10 days and ornidazole intravenously 500 mg twice daily for four days all proved ineffective. However, after a 5-day course of epsilon-9-aminacridine (100 mg three times daily by mouth) the diarrhoea ceased and both vegetative forms and lamblia cysts disappeared. These cases emphasize that lambliasis should be considered as a possible cause of severe chronic diarrhoea even when there is no history of travel abroad and when the symptoms are atypical. Conventional chemotherapeutic agents may be ineffective.

Disturbed intestinal absorption has been demonstrated almost uniformly early after intestinal autotransplantation. Our aim was to study the long-term effects of autotransplantation on intestinal absorptive function. Studies of nutritional status and absorptive function were performed on groups of dogs at three intervals after autotransplantation: I (less than 6 months; n = 4), II (6 to 12 months; n = 4), and III (12 to 18 months; n = 4). At death samples of intestinal fluid were obtained for bacteriologic analysis, and studies of morphology and in vitro absorption were performed on intact and autotransplanted intestine. Similar studies were performed on a group of five control animals. Although body weight and serum albumin levels remained stable in dogs that had undergone autotransplantation and initial diarrhea improved, stool moisture was persistently elevated and late defects in fat and D-xylose absorption developed (4.8% +/- 3.2% stool fat at 12 months vs 2.1% +/- 0.6% before surgery and 3.4 +/- 2.0 x 10(-2) mmol/L xylose/hr at 12 months vs 8.8 +/- 5.4 x 10(-2) mmol/L xylose/hr before surgery; p less than 0.05). In vitro glucose uptake and villus height were similar in autotransplanted and adjacent intact intestine at death. Compared with control animals, animals that had undergone autotransplantation demonstrated significant overgrowth of fecal flora in jejunum and ileum (14/18 segments greater than 10(5) bacteria vs 6/15 segments; p less than 0.05). Thus delayed defects in intestinal absorption of fat and D-xylose occurred more than 12 months after autotransplantation. Because intestinal structure and function of the autotransplanted intestine were similar to those of adjacent intact intestine, this malabsorption may be related to bacterial overgrowth or other in vivo factors.

The resistance to sterilization and disinfection of a novel replicating agent (IFDO) with similarities to Creutzfeldt-Jakob agent (CJA) was investigated. Moist heat at 121 degrees C for 30 min did not kill the agent. Increasing the temperature to 140 degrees C, and the length of the autoclave cycle to 120 min also failed to guarantee sterilization, although some samples were sterilized after these treatments. Dry heat at 160 degrees C for 1 h sterilized 24 of 25 samples. Overnight disinfection with 10% Stericol or 1.2% chlorhexidine left few detectable survivors. Samples pretreated with these disinfectants and then autoclaved at 134 degrees C for 20 min were sterilized. Disinfection with hypochlorite (500 ppm available chlorine) was very effective if organic matter derived from spent culture medium was removed. We have adopted overnight Stericol disinfection, followed by autoclaving at 134 degrees C for 1 h for sterilization of glassware contaminated by IFDO. The agent may provide a valid model for sterilization of items contaminated with CJA and, if so, our data suggest that current disinfection guidelines for CJA by autoclaving at 134 degrees C for 1 h are inadequate.

The influence of pancreatic secretions on the bacterial flora of the small intestine in 6 dogs was investigated by determining effects of exocrine pancreatic insufficiency on numbers and types of bacteria in duodenal juice, and by examining the subsequent response to dietary supplementation with bovine pancreatic extract. Exocrine pancreatic insufficiency was induced by ligation of pancreatic ducts and was confirmed by indirect assessment of exocrine pancreatic function. Duct ligation was followed by large increases (P less than 0.01) in total numbers of bacteria, reflecting increased numbers particularly of Lactobacillus spp and Streptococcus spp, in 3 dogs accompanied by obligate anaerobes. Total numbers of aerobes and anaerobes decreased markedly (P less than 0.05) after supplementation with bovine pancreatic extract to values that were not significantly different from those determined before duct ligation. Exocrine pancreatic insufficiency therefore resulted in small intestinal bacterial overgrowth that was reversed by pancreatic replacement therapy, indicating that pancreatic secretions can have an important influence on the small intestinal bacterial flora of dogs.

The bacterial immunofluorescence (BIF) in the intestinal juice was studied by the method of Virginia Thomas in a group of 26 patients with nonspecific chronic enteropathy (NCE). Our investigation revealed BIF in jejunal juice in 16 of 26 patients with NCE. The BIF test may be useful for the estimation of immune response to pathogenic germs at the level of the intestine.

Microecological problems have escalated recently in clinical medicine. We studied the microecology of the upper small bowel. Duodenal flora was examined, displaying microbial growth in 90.8% of the 400 patients examined. The microflora was classified according to germ quality into definite types of colonization. Frequency of microbial colonization is normally 36.7% and 63.3% by overgrowth, indicating differing dysbioses. Simulation of microbial overgrowth in the duodenum is possible with a continuous-flow culture, demonstrating a biocenosis of several groups of micro-organisms with great metabolic activity. Continuous culture technique suggests possibilities for future studies of human gastrointestinal microecology.

Normal and abnormal microflora of the upper small intestine was studied in 356 patients. Low counts are characteristic of normal microbial colonization (eubiosis), changes in quality and/or quantity are pathological (dysbiosis). The latter status is described as overgrowth syndrome. We found some types of dysbiosis. Prevalent was type Dys1 with the highest counts and the greatest variety of bacteria and yeasts. In contrast to this, type Dys2 showed higher germ counts of only one genus like coliforms (Dys2 Coli), streptococci (Dys2 Str.), lactobacilli (Dys2 L.) or yeasts (Dys2 Y.). In dysbiosis, we frequently saw bifidobacterium and bacteroides. Simultaneous sampling from stomach, duodenum, and jejunum indicated different modes of colonization of these parts (oral or fecal type).

The duodenal bacterial population was determined qualitatively and quantitatively in 3 groups of infants with diarrhoeal disease of varying duration. Infants with acute self limiting diarrhoea (group 1) had an abnormal overgrowth of organisms in the upper small bowel which was similar to that found in infants whose diarrhoea persisted after 4 days in hospital (group 2). The total duodenal organism count in infants with diarrhoea persisting after 7 days in hospital (group 3) was almost 100 times greater than either of the other groups. The findings may have important implications in preventing persistent diarrhoea from becoming protracted.

Both saliva and jejunal aspirate were cultured from 22 patients with suspected small bowel bacterial overgrowth and from eight controls. Large numbers of organisms (greater than 10(6)/ml) were recovered from the jejunal aspirate of 16 subjects, in five of whom the same organisms were present in similar relative proportions in the saliva, suggesting contamination of the sample with saliva, while in 11 the jejunal organisms differed from those in saliva. In eight of these the jejunal flora was a typical 'faecal' flora usually associated with small bowel bacterial overgrowth but, in three, the jejunal floral was superficially similar to that of saliva. Distinct subpopulations of bacteria, typically Gram-positive non-sporing rods, were, however, evident in the jejunum of these patients, and were also recovered, in smaller numbers, from the jejunum of controls, suggesting that they form a distinct jejunal microflora. Culture of saliva in addition to jejunal aspirate may be useful in the recognition of contamination of the proximal small bowel with saliva, and in the diagnosis of small bowel bacterial overgrowth.

Case report on a patient with agammaglobulinaemia, repeated respiratory infections, diarrhoea and nodular lymphoid hyperplasia of the small intestine. Giardia lamblia was seen in duodenal aspirates. B-lymphocytes were not decreased, but no plasma cells could be found. Later the patient developed a gastric carcinoma, which was also described in previous case reports.

The total concentration of short-chain fatty acids (SCFAs) in healthy subjects, measured by gas chromatography, was in saliva and jejunal aspirates (n = 6) (median (range] 4480 (2780-9940) mumol/l and 265 (185-1470) mumol/l and in gastric and duodenal aspirates (n = 7) 719 (425-1770) mumol/l and 480 (137-778) mumol/l, respectively. Acetic and propionic acid accounted for 85% and 11%, respectively, and i-butyric, n-butyric, and i-valeric for less than 2% each in jejunal aspirates. A very similar relative distribution was present also in saliva and gastric and duodenal aspirates, essentially different from that of feces. Through anaerobic culturing from jejunum, 10(3) to 10(8) bacteria/ml was obtained; there was no correlation between the log number of bacteria and the SCFAs concentration before and after ingestion of sucrose. Swallowed exogenous radiolabeled propionate was partly recovered in the jejunum. The findings indicate that the SCFAs recovered from the jejunum in healthy subjects are mainly produced in the mouth and swallowed with the saliva.

Bacteriological studies of uncontaminated upper jejunal fluid were performed in 85 normal subjects. Fifty-three per cent of the samples were sterile (less than 10(1) CFU/ml). In 10% of the cases the total number of microorganisms exceeded 10(5) CFU/ml. The main groups of microorganisms isolated were Streptococcus sp ('Viridans group'), Lactobacillus sp., Veillonella parvula, Actinomyces sp., Haemophilus sp., Corynebacterium sp., and Candida albicans, each found in more than 10% of the subjects. Only the Streptococcus sp. exceeded 10(5) CFU/ml, and enterobacteria were found in 5% of the subjects, the number not exceeding 10(3) CFU/ml. No other typical members of the lower gastrointestinal tract were isolated. The number of subjects harbouring bacteria and the distribution of bacterial species were the same in both sexes and in different age groups.

Antibacterial activity could be detected in bacterium-negative duodenal juice from 3 patients, whereas it was not detected in bacterium-positive duodenal juice from other 3 patients. The follow-up study revealed that appearance of the activity in duodenal juice was just coincident with disappearance of bacteria in duodenal juice. The activity was not influenced by pH of the duodenal juice. These results seem to suggest that some antibacterial activity, different from that of pH, in duodenal juice regulates in some way proliferation of the upper gastrointestinal flora.

Escherichia coli (2), Vibrio cholerae (2) and Aeromonas sobria (1) strains were examined for their ability to grow and produce toxins in samples of ileostomy fluid. Three categories of response were observed: no detectable growth, growth without detectable toxin, and growth with detectable toxin. Clear differences were apparent between samples of ileostomy fluid obtained from different individuals and between samples obtained from the same individual at different times. The patterns of response were unique for each of the five test strains. We propose that the procedure developed forms a basis for investigating the host-parasite relationship in diarrhoeal disease.

Following preincubation of intrinsic factor- (IF-) bound 57CoB12 with the jejunal sediments of 6 patients with the blind-loop syndrome, the mean uptake by the sediments of IF-57CoB12 (28.1 percent plus or minus 4.2 percent S,E.M.) was significantly higher than the mean uptake by jejunal sediments from 5 control patients (5.8 per cent plus or minus 3.5 percent) (p smaller than 0.01). The uptake by the sediments significantly decreased when the incubations were carried out in the presence of lincomycin and neomycin. The jejunal sediments from the patients with the blind-loop syndrome inhibited the uptake of IF-57CoB12 by perfused rat intestinal segments (p smaller than 0.01), whereas the sediments from the control patients had no such inhibitory effect (p smaller than 0.5).

The exocrine pancreatic function was investigated in 16 patients with progressive systemic sclerosis by means of a meal test (Lundh test) and in 9 of the patients by the secretin-cholecystokinin test as well. Gastrointestinal involvement with progressive systemic sclerosis was evaluated by esophageal manometry and by routine roentgenographic series of the small bowel. Fecal fat excretion measurement, the D-xylose absorption test, and a small-intestinal biopsy procedure were carried out. Duodenal juice was cultured and bacterial counts were estimated. One-third of the patients had reduced exocrine pancreatic function, but only four patients had unequivocally a reduction that could be of clinical importance. The results obtained with the meal test were in accordance with the secretin-cholecystokinin test, indicating a preserved capacity for endogenous stimulation.