Introduction: Infectious diseases constitute a major concern of public health in developing countries. Facilities and well trained staff have been shown to be one of the major obstacles in the rapid and quality diagno...Introduction: Infectious diseases constitute a major concern of public health in developing countries. Facilities and well trained staff have been shown to be one of the major obstacles in the rapid and quality diagnosis of these diseases. As such, we carried out an analysis to compare the Widal test and stool culture to identify febrile patients with Salmonella infection. Method: A cross sectional study was conducted to diagnose salmonella infection with out-patients who demonstrated signs of salmonella infection. Serum was harvested from blood collected from 368 (Vina = 234, Mayo Banyo 65, and Djerem = 69) patients accompanied by stool, Widal test was conducted on the spot and stool was taken to a reference laboratory for culture using standard microbiological methods, sociological set up was calculated in percentages, prevalence was calculated using excel while statistical difference was calculated using SPSS. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to compare the Widal test against stool culture. Results: A total of 368 (50.8% females and 49.2% males) participants took part in the survey. Salmonella prevalence (66.24%) in stool culture in the Vina division was significantly different (p 0.05). The sensitivity,specificity, PPV, and NPV of slide agglutination test against stool culture varied from different areas (Vina: 51.6%, 73.62%, 79.21% and 43.61%;Mayo Banyo: 60.53%, 77.78%, 79.31% and 58.33%;Djerem: 53.18%, 83.73% 73.91% and 67.39%) respectively. Slide agglutination test has a fair agreement with the stool culture (kappa, Vina = 0.202;Mayo Banyo = 0.37 and Djerem = 0.38). Conclusion: Generally, in the three areas of study, the Widal test had a fair correlation with the stool culture;This means the Widal test should not be used alone but in combination with stool culture in the detection of salmonella infections.展开更多
Human milk is considered to be the optimal source of infant nutrition. Some of the benefits of breastfeeding have been ascribed to human milk oligosaccharides(HMO). For instance, HMO can affect faecal characteristics ...Human milk is considered to be the optimal source of infant nutrition. Some of the benefits of breastfeeding have been ascribed to human milk oligosaccharides(HMO). For instance, HMO can affect faecal characteristics such as stool consistency and stool frequency. Such effects on stool characteristics can be beneficial for young infants as hard stools and even constipation is common in that age group. Prebiotics in infant milk formulas have been introduced to exert similar functionalities. A specific mixture of prebiotics consists of a combination of short chain galacto-oligosaccharides and long-chain fructo-oligosaccharides(scGOS/lcFOS) in a ratio of 9:1. This specific mixture has been developed to closely resemble the molecular size composition of HMO. Many studies have been done with scGOS/lcFOS, and indicators for digestive comfort have often been included as secondary outcomes. This review summarizes the effects of scGOS/lcFOS(9:1) on stool consistency,stool frequency and transit time in healthy term and preterm infants. In several of the studies with scGOS/lcFOS in a ratio of 9:1 in infant milk formulas, positive effects of this mixture on stool characteristics such as stool consistency and stool frequency were observed. As stool consistency was shown to be correlated to whole gut transit time, scGOS/lcFOS can be hypothesised to have a role in reducing the risk of constipation.展开更多
Stool antigen tests(SATs)are noninvasive diagnostic modules for Helicobacter pylori(H.pylori)infection.Two types of SATs exist for the diagnosis of H.pylori infection,one based on enzyme immunoassay(EIA)and another on...Stool antigen tests(SATs)are noninvasive diagnostic modules for Helicobacter pylori(H.pylori)infection.Two types of SATs exist for the diagnosis of H.pylori infection,one based on enzyme immunoassay(EIA)and another on immunochromatography(ICA).SATs do not require expensive chemical agents or specified equipment;hence,they are less expensive compared with the urea breath test.Both European and Japanese guidelines have shown that EIA-based SATs using monoclonal antibodies are useful for primary diagnosis as well as for the assessment of eradication therapy.ICA-based tests do not require particular equipment and are therefore useful in developing countries.SATs are also useful for the diagnosis of H.pylori infection in children and post gastric surgery patients.SATs performed via EIA can assess H.pylori infection in a large number of subjects,almost as well as serology.Thus,SATs would be useful or detecting current infection in such a survey to identify and eradicate H.pylori infection.The accuracy of SATs is lower when the stool samples are unformed or watery,because H.pylorispecific antigens in the stool samples are diluted.Temperature and the interval between stool sample collection and measurement also affect the results of SATs.The choice of test kit depends on the sensitivity and specificity in each region and the circumstances of each patient.展开更多
AIM: To investigate the effects of proton pump inhibitor (PPI) treatment on stool antigen test using the TestMate pylori enzyme immunoassay. METHODS: This study assessed 28 patients [16 men and 12 women; mean age (63....AIM: To investigate the effects of proton pump inhibitor (PPI) treatment on stool antigen test using the TestMate pylori enzyme immunoassay. METHODS: This study assessed 28 patients [16 men and 12 women; mean age (63.1 ± 5.9) years; range, 25-84 years] who underwent stool antigen test and urea breath test (UBT) before and after PPI administration. RESULTS: Using the UBT as the standard, the sensitivity, specif icity and agreement of the stool antigen test in all 28 patients were 95.2%, 71.4%, and 89.3%, respectively, before PPI administration, and 88.9%, 90.9%, and 89.3%, respectively, after PPI treatment. Mean UBT values were 23.98% ± 5.33% before and 16.19% ± 4.75% after PPI treatment and, in 15 patients treated for ≥ 4 wk, were signif icantly lower after than before 4 wk of PPI treatment (12.58% ± 4.49% vs 24.53% ± 8.53%, P = 0.048). The mean optical density (A450/630) ratios on the stool antigen test were 1.16 ± 0.20 before and 1.17 ± 0.24 after PPI treatment (P = 0.989), and were 1.02 ± 0.26 and 0.69 ± 0.28, respectively, in the group treated for > 4 wk (P = 0.099).展开更多
AIM： To detect tumor-associated DNA changes in stool samples among Iranian patients with colorectal cancer （CRC） compared to healthy individuals using BAT-26, p16 hypermethylation and long DNA markers. METHODS： St...AIM： To detect tumor-associated DNA changes in stool samples among Iranian patients with colorectal cancer （CRC） compared to healthy individuals using BAT-26, p16 hypermethylation and long DNA markers. METHODS： Stool DNA was isolated from 45 subjects including 25 CRC patients and 20 healthy individuals using a new, fast and easy extraction method. Long DNA associated with tumor was detected using polymerase chain reaction method. Microsatellite studies were performed utilizing denaturating polyacrylamide gel to determine the instability of BAT-26. Methylation status of p16 promoter was analyzed using methylation-specific PCR （MSP）. RESULTS： The results showed a significant difference in existence of long DNA （16 in patients vs 1 in controls, P 〈 0.001） and p16 （5 in patients vs none in controls, P = 0.043） in the stool samples of two groups. Long DNA was detected in 64% of CRC patients; whereas just one of the healthy individuals was positive for Long DNA. p16 methylation was found in 20% of patients and in none of healthy individuals. Instability of BATo26 was not detected in any of stool samples. CONCLUSION： We could detect colorectal cancer related genetic alterations by analyzing stool DNA with a sensitivity of 64% and 20% and a specificity of 95% and 100% for Long DNA and p16 respectively. A non- invasive molecular stool-based DNA testing can provide a screening strategy in high-risk individuals. However, additional testing on more samples is necessary from Iranian subjects to determine the exact specificity and sensitivity of these markers.展开更多
Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).T...Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).The United States Preventive Services Task Force(USPSTF) October 2015 draft recommendation for CRC screening included mt-s DNA as an "alternative" screening test that "may be useful in select clinical circumstances",despite its very high sensitivity for early stage CRC.The evidence supporting mt-s DNA for routine screening use is robust.The clinical efficacy of mt-s DNA as measured by sensitivity,specificity,life-years gained(LYG),and CRC deaths averted is similar to or exceeds that of the other more specifically recommended screening options included in the draft document,especially those requiring annual testing adherence.In a population with primarily irregular screening participation,tests with the highest point sensitivity and reasonable specificity are more likely to favorably impact CRC related morbidity and mortality than those depending on annual adherence.This paper reviews the evidence supporting mt-s DNA for routine screening and demonstrates,using USPSTF's modeling data,that mt-s DNA at three-year intervals provides significant clinical net benefits and fewer complications per LYG than annual fecal immunochemical testing,high sensitivity guaiac based fecal occult blood testing and 10-year colonoscopy screening.展开更多
AIM: To determine the bowel symptoms associated with diabetes and diabetes-related factors after excluding gastrointestinal (GI) organic diseases.METHODS: Participants were 4738 (603 diabetic and 4135 non-diabetic) pa...AIM: To determine the bowel symptoms associated with diabetes and diabetes-related factors after excluding gastrointestinal (GI) organic diseases.METHODS: Participants were 4738 (603 diabetic and 4135 non-diabetic) patients who underwent colonoscopy and completed a questionnaire. On the day of pre-colonoscopy, 9 symptoms (borborygmus, abdominal distension, increased flatus, constipation, diarrhea, loose stools, hard stools, fecal urgency, and incomplete evacuation) were prospectively evaluated on a 7-point Likert scale. The test-retest reliability of the bowel symptom scores from the baseline and second questionnaires was analyzed using kappa statistics. Associations between bowel symptom scores and diabetes or diabetes-related factors were analyzed by a rank-ordered logistic model adjusted for related confounders, and odds ratios (ORs) were estimated.RESULTS: In multivariate analysis, constipation [adjusted odds ratio (AOR) = 1.57, CI: 1.33-1.85, P < 0.01] and hard stools (AOR = 1.56, CI: 1.33-1.84, P < 0.01) were associated with diabetes, and fecal urgency (AOR = 1.16, CI: 0.99-1.37, P = 0.07) and incomplete evacuation (AOR = 1.16, CI: 1.00-1.36, P = 0.06) were marginally associated with diabetes. These symptoms remained associated even after excluding organic GI diseases on colonoscopy. Test-retest reliability of symptom score with a mean duration of 3.2 mo was good (mean kappa, 0.69). Associations of symptoms with diabetes-related factors were found; constipation with HbA1c ≥ 8.0% (AOR = 2.11, CI: 1.19-3.73), body mass index (BMI) < 25 (AOR = 2.11, CI: 1.22-3.66), and insulin use (AOR = 1.90, CI: 1.08-3.36); hard stools with diabetes duration (AOR = 1.03, CI: 1.00-1.07); fecal urgency with BMI < 25 (AOR = 1.73, CI: 1.00-2.98); and incomplete evacuation with BMI < 25 (AOR = 2.60, CI: 1.52-4.43), serum creatinine level (AOR = 1.27, CI: 1.10-1.47), and insulin use (AOR = 1.92, CI: 1.09-3.38).CONCLUSION: Diabetes is associated with constipation, hard stools, fecal urgency, and incomplete evacuation, and poor glycemic control, duration, leanness, and nephropathy affect the risk of these symptoms.展开更多
Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected...Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,Philippines.These samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis sp.Results:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis sp.by two or more tests.Culture method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal smear.Specificity of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis sp.in human stool samples.展开更多
Objective: Despite the high prevalence of CRC and the proven benefits of faecal sampling tests, participation rates in CRC screening are suboptimal. Literature has identified a number of barriers to participation, inc...Objective: Despite the high prevalence of CRC and the proven benefits of faecal sampling tests, participation rates in CRC screening are suboptimal. Literature has identified a number of barriers to participation, including faecal aversion. Emerging test technologies suggest blood-based molecular markers might provide an alternative, more acceptable option, for CRC screening tests. We aim to determine preference for blood compared to faeces as the sample for the screening test. Methods: A survey was mailed to 956 South Australians aged 50 to 74 years. Data were collected on sample preference, demographic variables, and ratings of screening test convenience and comfort. Results: The survey yielded a 43% response rate. The majority of participants preferred to provide a blood sample (78% v 22%, p < 0.001). Women were more likely to prefer blood than men (82% vs 74%, p = 0.05). Sample experience influenced preferences, with a significantly higher preference for faeces among participants with experience in faecal sampling (27% vs 17% with no experience, p < 0.05). Participants who preferred to provide a faecal sample rated it significantly more convenient (p < 0.001), more comfortable (p < 0.001), and more acceptable (p < 0.001) than those who preferred blood sampling. Conclusions: Survey participants overwhelmingly indicate a preference for the idea of a blood sample over a faecal sample for CRC screening. Preference was influenced by gender, experience with sampling method and the individual’s perception of sampling convenience, sampling comfort and sample acceptability. Our results suggest population participation rates are likely to improve with blood-based screening tests.展开更多
AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cr...AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens,CONCLUSION:Regard to high similarity in genotype of H.pylori isolates from saliva,stomach and stool,this study support the idea which fecal-oral is the main route of H.pylori transmission and oral cavity may serve as a reservoir for H.pylori,however,remarkable genotype diversity among stomach,saliva and stool samples showed that more than one H.pylori genotype may exist in a same patient.展开更多
AIM To determine the uptake of noninvasive multitarget stool DNA (mt-s DNA) in a cohort of colorectal cancer(CRC) screening non-compliant average-risk Medicare patients.METHODS This cross sectional primary care office...AIM To determine the uptake of noninvasive multitarget stool DNA (mt-s DNA) in a cohort of colorectal cancer(CRC) screening non-compliant average-risk Medicare patients.METHODS This cross sectional primary care office-based study examined mt-s DNA uptake in routine clinical practice among 393 colorectal cancer screening non-compliant Medicare patients ages 50-85 ordered by 77 physicians in a multispecialty group practice (USMD Physician Services, Dallas, TX) from October, 2014-September, 2015. Investigators performed a Health Insurance Portability and Accountability Act compliant retrospective review of electronic health records to identify mt-s DNA use in patients who were either > 10 years since last colonoscopy and/or > 1 year since last fecal occult blood test. Test positive patients were advised to get diagnostic colonoscopy and thereafter patients were characterized by the most clinically significant lesion documented on histopathology of biopsies or excisional tissue. Descriptive statistics were employed. Key outcome measures included mt-s DNA compliance and diagnostic colonoscopy compliance on positive cases.RESULTS Over 12 mo, 77 providers ordered 393 mt-sD NA studies with 347 completed (88.3% compliance). Patient mean age was 69.8 (50-85) and patients were 64% female. Mt-sD NA was negative in 85.3%(296/347) and positive in 14.7%(51/347). Follow-up colonoscopy was performed in 49 positive patients (96.1% colonoscopy compliance) with two patients lost to follow up. Index findings included: colon cancer(4/49, 8.2%), advanced adenomas (21/49, 42.9%), non-advanced adenomas(15/49, 30.6%), and negative results (9/49, 18.4%). The positive predictive value for advanced colorectal lesions was 51.0% and for any colorectal neoplasia was 81.6%. The mean age of patients with colorectal cancer was 70.3 and all CRC's were localized Stage Ⅰ(2) and Stage Ⅱ (2), three were located in the proximal colon and one was located in the distal colon.CONCLUSION Mt-s DNA provided medical benefit to screening noncompliant Medicare population. High compliance with mt-s DNA and subsequent follow-up diagnostic colonoscopy identified patients with clinically critical advanced colorectal neoplasia.展开更多
AIM To study cancer hotspot mutations by next-generation sequencing(NGS) in stool DNA from patients with different gastrointestinal tract(GIT) neoplasms. METHODS Stool samples were collected from 87 Finnish patients d...AIM To study cancer hotspot mutations by next-generation sequencing(NGS) in stool DNA from patients with different gastrointestinal tract(GIT) neoplasms. METHODS Stool samples were collected from 87 Finnish patients diagnosed with various gastric and colorectal neoplasms, including benign tumors, and from 14 healthy controls. DNA was isolated from stools by usingthe PSP~? Spin Stool DNA Plus Kit. For each sample, 20 ng of DNA was used to construct sequencing libraries using the Ion AmpliS eq Cancer Hotspot Panel v2 or Ion AmpliS eq Colon and Lung Cancer panel v2. Sequencing was performed on Ion PGM. Torrent Suite Software v.5.2.2 was used for variant calling and data analysis.RESULTS NGS was successful in assaying 72 GIT samples and 13 healthy controls, with success rates of the assay being78% for stomach neoplasia and 87% for colorectal tumors. In stool specimens from patients with gastric neoplasia, five hotspot mutations were found in APC,CDKN2 A and EGFR genes, in addition to seven novel mutations. From colorectal patients, 20 mutations were detected in AKT1, APC, ERBB2, FBXW7, KIT, KRAS,NRAS, SMARCB1, SMO, STK11 and TP53. Healthy controls did not exhibit any hotspot mutations, except for two novel ones. APC and TP53 were the most frequently mutated genes in colorectal neoplasms, with five mutations, followed by KRAS with two mutations.APC was the most commonly mutated gene in stools of patients with premalignant/benign GIT lesions.CONCLUSION Our results show that in addition to colorectal neoplasms,mutations can also be assayed from stool specimens of patients with gastric neoplasms.展开更多
A comparative study was performed to evaluate best practice culture media and enrichment broths for recovering Salmonella species from human stool samples. A total of 1297 human stools were collected and processed in ...A comparative study was performed to evaluate best practice culture media and enrichment broths for recovering Salmonella species from human stool samples. A total of 1297 human stools were collected and processed in this study. Evaluation of agar media was carried out by direct plating (DP), 1096 stool samples were inoculated on Modified Semisolid Rappaport-Vassiliadis (MSRV), Xylose-Lysine-Deoxycolate (XLD), MacConkey (MAC), and Hektoen Enteric (HE) agars. Evaluation of enrichment broths were carried out by enrichment all 1297 stool samples in Selenite broth (SB), Rappaport-Vassiliadis (RV) broth, and Buffered Peptone Water (BPW), followed by plating on MSRV, MAC, and HE agars. A total of 102 Salmonella-positive stools by DP, 85.3% (87/102) were recovered utilizing MSRV while recovery from XLD, MAC, and HE agars were 34.3% (35/102), 34.3% (35/102), and 29.4% (30/102) respectively. A total 299/1297 stools samples were Salmonella-positive on at least one plating medium after enrichment procedure were 77.3% (177/299) for SB, 86.0% (197/299) and 78.6% (180/299) for RV and BPW respectively. All Salmonella isolated in this study was nontyphi Salmonella. Presently, the data suggest that the use of MSRV over MAC, HE, and XLD agars for isolation nontyphi Salmonella species from human stools is more efficacious. Additionally, use of MSRV in combination with MAC and HE agars following enrichment in RV broth enhances recovery of nontyphi Salmonella species. However, RV broth is inhibitory to typhi Salmonella, thus use of MSRV medium in combination with MAC, HE or XLD agars in direct plating following enrichment in non-selective BPW is an alternate method for recovery of both typhi and nontyphi Salmonella species contaminated in human stool samples.展开更多
Introduction and Objective: The genus Bifidobacterium can generally be found in quantity in the habitats such as human and animal gastrointestinal tract, dental caries, vagina and oral cavity. The aim of this study wa...Introduction and Objective: The genus Bifidobacterium can generally be found in quantity in the habitats such as human and animal gastrointestinal tract, dental caries, vagina and oral cavity. The aim of this study was to isolate Bifidobacterium from stool and determine their inhibitory effect against some pathogens. Materials and Methods: 130 samples were collected by wet swabs and kept in sterile tubes containing MRS broth media. And Bifidobacterium isolated from stool was enriched in Man-Rogosa-Sharpe medium (MRS) broth and isolated by growing on MRS agar medium and characterized by phenotypic characteristics and PCR technique at genus and species levels. The antimicrobial substance was extracted from ethyl acetate solvent and the antimicrobial activity against some pathogenic bacteria, such as Salmonella typhi and Shigella sonnei, were investigated. Results: Eleven Bifidobacterium bifidum and four Bifidobacterium adolescentis, which were isolated from fresh stool, were identified by PCR. Antimicrobial substance from MRS broth medium was extracted. This antimicrobial compound showed a potent inhibitory activity against four tested bacteria. These bacteria produced acetic acid and lactic acid as inhibitory substances that were different from bacteriocins. Conclusion: Fresh stool may be used as a source of antimicrobial lactic acids bacteria, Bifidobacterium bifidum and adolescentis as two probiotics can establish themselves in gut and urogenital tract to prevent the human body from adverse effects of pathogens.展开更多
BACKGROUND Colorectal cancer(CRC)is a major global health burden.The current diagnostic tests have shortcomings of being invasive and low accuracy.AIM To explore the combination of intestinal microbiome composition an...BACKGROUND Colorectal cancer(CRC)is a major global health burden.The current diagnostic tests have shortcomings of being invasive and low accuracy.AIM To explore the combination of intestinal microbiome composition and multi-target stool DNA(MT-sDNA)test in the diagnosis of CRC.METHODS We assessed the performance of the MT-sDNA test based on a hospital clinical trial.The intestinal microbiota was tested using 16S rRNA gene sequencing.This case-control study enrolled 54 CRC patients and 51 healthy controls.We identified biomarkers of bacterial structure,analyzed the relationship between different tumor markers and the relative abundance of related flora components,and distinguished CRC patients from healthy subjects by the linear discriminant analysis effect size,redundancy analysis,and random forest analysis.RESULTS MT-sDNA was associated with Bacteroides.MT-sDNA and carcinoembryonic antigen(CEA)were positively correlated with the existence of Parabacteroides,and alpha-fetoprotein(AFP)was positively associated with Faecalibacterium and Megamonas.In the random forest model,the existence of Streptococcus,Escherichia,Chitinophaga,Parasutterella,Lachnospira,and Romboutsia can distinguish CRC from health controls.The diagnostic accuracy of MT-sDNA combined with the six genera and CEA in the diagnosis of CRC was 97.1%,with a sensitivity and specificity of 98.1%and 92.3%,respectively.CONCLUSION There is a positive correlation of MT-sDNA,CEA,and AFP with intestinal microbiome.Eight biomarkers including six genera of gut microbiota,MT-sDNA,and CEA showed a prominent sensitivity and specificity for CRC prediction,which could be used as a non-invasive method for improving the diagnostic accuracy for this malignancy.展开更多
BACKGROUND Recently,stool multiplex polymerase chain reaction(PCR)tests have been developed for identifying diarrhea-causing bacterial pathogens.Furthermore,fecal calprotectin is a well-known effective marker for inte...BACKGROUND Recently,stool multiplex polymerase chain reaction(PCR)tests have been developed for identifying diarrhea-causing bacterial pathogens.Furthermore,fecal calprotectin is a well-known effective marker for intestinal mucosal inflammation.AIM To evaluate the efficacy of stool multiplex PCR and fecal calprotectin in acute infectious diarrhea.METHODS Overall,400 patients with acute infectious diarrhea were enrolled from Kangdong Sacred Heart Hospital(January 2016 to December 2018).Multiplex PCR detected 7 enteropathogenic bacteria including Salmonella,Campylobacter,Shigella,Escherichia coli O157:H7,Aeromonas,Vibrio,and Clostridium difficile.We reviewed clinical and laboratory findings using stool multiplex PCR.RESULTS Stool multiplex PCR test detected considerably more bacterial pathogens than stool culture(49.2%vs 5.2%),with Campylobacter as the most common pathogen(54%).Patients with positive stool PCR showed elevated fecal calprotectin expression compared to patients with negative stool PCR(1124.5±816.9 mg/kg vs 609±713.2 mg/kg,P=0.001).C-reactive protein(OR=1.01,95%CI:1.001-1.027,P=0.034)and sigmoidoscopy-detected colitis(OR=4.76,95%CI:1.101-20.551,P=0.037)were independent factors in stool PCR-based detection of bacterial pathogens.Sensitivity and specificity of calprotectin were evaluated to be 70.5%and 60.9%,respectively(adjusted cut-off value=388 mg/kg).CONCLUSION Stool multiplex PCR test has increased sensitivity in detecting pathogens than conventional culture,and it is correlated with calprotectin expression.Stool multiplex PCR and calprotectin may be effective in predicting clinical severity of infectious diarrhea.展开更多
AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients ...AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients with stage I-IV CRC diagnosed by preoperative biopsy. KRAS mutational status was determined by pyrosequencing analysis of DNA obtained from formalin-fixed paraffin-embedded (FFPE) tumor tissues. The KRAS G12D mutation was then analyzed by ddPCR in FFPE tumors and stool-derived DNA from patients with this point mutation. Wild-type (WT) tumors, as determined by pyrosequencing, were included as controls; analysis of FFPE tissue and stool-derived DNA by ddPCR was performed for these patients as well.RESULTSAmong the total 70 patients included, KRAS mutations were detected by pyrosequencing in 32 (45.71%), whereas 38 (54.29%) had WT tumors. The frequency of KRAS mutations was higher in left-sided tumors (11 located in the right colon, 15 in the left, and 6 in the rectum). The predominant point mutation was KRAS G12D (14.29%, n = 10), which was more frequent in early-stage tumors (I-IIA, n = 7). In agreement with pyrosequencing results, the KRAS G12D mutation was detected by ddPCR in FFPE tumor-derived DNA, and only a residual number of mutated copies was found in WT controls. The KRAS G12D mutation was also detected in stool-derived DNA in 80% of all fecal samples from CRC patients with this point mutation.CONCLUSIONddPCR is a reliable and sensitive method to analyze KRAS G12D mutation in stool-derived DNA from CRC patients, especially at early stages. This non-invasive approach is potentially applicable to other relevant biomarkers for CRC management.展开更多
AIM： To evaluate the agreement between a mAb-based stool test （HP STAR） and the urea breath test （UBT） in monitoring （H pylon） infection after eradication therapy. METHODS： Patients with discordant results on ...AIM： To evaluate the agreement between a mAb-based stool test （HP STAR） and the urea breath test （UBT） in monitoring （H pylon） infection after eradication therapy. METHODS： Patients with discordant results on UBT and Hp STAR underwent endoscopy with biopsies for rapid urease test, culture, and histology to confirm H pylori status. RESULTS： Among 250 patients （50±14 years）, 240 （96.0%） had concordant UBT and Hp STAR tests with a significant correlation between DOB and A values （R = 0.87; P〈0.0001）. The remaining 10 （4.0%） patients had discordant tests （positive Hp STAR and negative UBT） with the Hp STAR inaccurate in five cases （false positive） and UBT inaccurate in the other five cases （false negative）. The “maximal expected” sensitivity, specificity, ＋PV, -PV, ＋LR, and -LR were 91%, 100%, 100%, 97.4%, ∞, and 8.2 respectively, for the UBT, and 100%, 97.4%, 91%, 100%, 38.8, and 0, respectively, for the Hp STAR. Overall accuracy for both tests was 98%. CONCLUSION： Both the UBT and the Hp StAR are equally accurate in monitoring H pylori infection. Nowadays, the choice of the “best” non-invasive H pylori test in the post-treatment setting should be done not only in terms of diagnostic accuracy but also in view of cost and local facilities.展开更多
文摘Introduction: Infectious diseases constitute a major concern of public health in developing countries. Facilities and well trained staff have been shown to be one of the major obstacles in the rapid and quality diagnosis of these diseases. As such, we carried out an analysis to compare the Widal test and stool culture to identify febrile patients with Salmonella infection. Method: A cross sectional study was conducted to diagnose salmonella infection with out-patients who demonstrated signs of salmonella infection. Serum was harvested from blood collected from 368 (Vina = 234, Mayo Banyo 65, and Djerem = 69) patients accompanied by stool, Widal test was conducted on the spot and stool was taken to a reference laboratory for culture using standard microbiological methods, sociological set up was calculated in percentages, prevalence was calculated using excel while statistical difference was calculated using SPSS. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated to compare the Widal test against stool culture. Results: A total of 368 (50.8% females and 49.2% males) participants took part in the survey. Salmonella prevalence (66.24%) in stool culture in the Vina division was significantly different (p 0.05). The sensitivity,specificity, PPV, and NPV of slide agglutination test against stool culture varied from different areas (Vina: 51.6%, 73.62%, 79.21% and 43.61%;Mayo Banyo: 60.53%, 77.78%, 79.31% and 58.33%;Djerem: 53.18%, 83.73% 73.91% and 67.39%) respectively. Slide agglutination test has a fair agreement with the stool culture (kappa, Vina = 0.202;Mayo Banyo = 0.37 and Djerem = 0.38). Conclusion: Generally, in the three areas of study, the Widal test had a fair correlation with the stool culture;This means the Widal test should not be used alone but in combination with stool culture in the detection of salmonella infections.
文摘Human milk is considered to be the optimal source of infant nutrition. Some of the benefits of breastfeeding have been ascribed to human milk oligosaccharides(HMO). For instance, HMO can affect faecal characteristics such as stool consistency and stool frequency. Such effects on stool characteristics can be beneficial for young infants as hard stools and even constipation is common in that age group. Prebiotics in infant milk formulas have been introduced to exert similar functionalities. A specific mixture of prebiotics consists of a combination of short chain galacto-oligosaccharides and long-chain fructo-oligosaccharides(scGOS/lcFOS) in a ratio of 9:1. This specific mixture has been developed to closely resemble the molecular size composition of HMO. Many studies have been done with scGOS/lcFOS, and indicators for digestive comfort have often been included as secondary outcomes. This review summarizes the effects of scGOS/lcFOS(9:1) on stool consistency,stool frequency and transit time in healthy term and preterm infants. In several of the studies with scGOS/lcFOS in a ratio of 9:1 in infant milk formulas, positive effects of this mixture on stool characteristics such as stool consistency and stool frequency were observed. As stool consistency was shown to be correlated to whole gut transit time, scGOS/lcFOS can be hypothesised to have a role in reducing the risk of constipation.
文摘Stool antigen tests(SATs)are noninvasive diagnostic modules for Helicobacter pylori(H.pylori)infection.Two types of SATs exist for the diagnosis of H.pylori infection,one based on enzyme immunoassay(EIA)and another on immunochromatography(ICA).SATs do not require expensive chemical agents or specified equipment;hence,they are less expensive compared with the urea breath test.Both European and Japanese guidelines have shown that EIA-based SATs using monoclonal antibodies are useful for primary diagnosis as well as for the assessment of eradication therapy.ICA-based tests do not require particular equipment and are therefore useful in developing countries.SATs are also useful for the diagnosis of H.pylori infection in children and post gastric surgery patients.SATs performed via EIA can assess H.pylori infection in a large number of subjects,almost as well as serology.Thus,SATs would be useful or detecting current infection in such a survey to identify and eradicate H.pylori infection.The accuracy of SATs is lower when the stool samples are unformed or watery,because H.pylorispecific antigens in the stool samples are diluted.Temperature and the interval between stool sample collection and measurement also affect the results of SATs.The choice of test kit depends on the sensitivity and specificity in each region and the circumstances of each patient.
文摘AIM: To investigate the effects of proton pump inhibitor (PPI) treatment on stool antigen test using the TestMate pylori enzyme immunoassay. METHODS: This study assessed 28 patients [16 men and 12 women; mean age (63.1 ± 5.9) years; range, 25-84 years] who underwent stool antigen test and urea breath test (UBT) before and after PPI administration. RESULTS: Using the UBT as the standard, the sensitivity, specif icity and agreement of the stool antigen test in all 28 patients were 95.2%, 71.4%, and 89.3%, respectively, before PPI administration, and 88.9%, 90.9%, and 89.3%, respectively, after PPI treatment. Mean UBT values were 23.98% ± 5.33% before and 16.19% ± 4.75% after PPI treatment and, in 15 patients treated for ≥ 4 wk, were signif icantly lower after than before 4 wk of PPI treatment (12.58% ± 4.49% vs 24.53% ± 8.53%, P = 0.048). The mean optical density (A450/630) ratios on the stool antigen test were 1.16 ± 0.20 before and 1.17 ± 0.24 after PPI treatment (P = 0.989), and were 1.02 ± 0.26 and 0.69 ± 0.28, respectively, in the group treated for > 4 wk (P = 0.099).
基金Supported by a grant from the vice chancellor for research at Mashhad University of Medical Sciences,NO. 84082
文摘AIM： To detect tumor-associated DNA changes in stool samples among Iranian patients with colorectal cancer （CRC） compared to healthy individuals using BAT-26, p16 hypermethylation and long DNA markers. METHODS： Stool DNA was isolated from 45 subjects including 25 CRC patients and 20 healthy individuals using a new, fast and easy extraction method. Long DNA associated with tumor was detected using polymerase chain reaction method. Microsatellite studies were performed utilizing denaturating polyacrylamide gel to determine the instability of BAT-26. Methylation status of p16 promoter was analyzed using methylation-specific PCR （MSP）. RESULTS： The results showed a significant difference in existence of long DNA （16 in patients vs 1 in controls, P 〈 0.001） and p16 （5 in patients vs none in controls, P = 0.043） in the stool samples of two groups. Long DNA was detected in 64% of CRC patients; whereas just one of the healthy individuals was positive for Long DNA. p16 methylation was found in 20% of patients and in none of healthy individuals. Instability of BATo26 was not detected in any of stool samples. CONCLUSION： We could detect colorectal cancer related genetic alterations by analyzing stool DNA with a sensitivity of 64% and 20% and a specificity of 95% and 100% for Long DNA and p16 respectively. A non- invasive molecular stool-based DNA testing can provide a screening strategy in high-risk individuals. However, additional testing on more samples is necessary from Iranian subjects to determine the exact specificity and sensitivity of these markers.
文摘Multitarget stool DNA(mt-sDNA) testing was approved for average risk colorectal cancer(CRC) screening by the United States Food and Drug Administration and thereafter reimbursed for use by the Medicare program(2014).The United States Preventive Services Task Force(USPSTF) October 2015 draft recommendation for CRC screening included mt-s DNA as an "alternative" screening test that "may be useful in select clinical circumstances",despite its very high sensitivity for early stage CRC.The evidence supporting mt-s DNA for routine screening use is robust.The clinical efficacy of mt-s DNA as measured by sensitivity,specificity,life-years gained(LYG),and CRC deaths averted is similar to or exceeds that of the other more specifically recommended screening options included in the draft document,especially those requiring annual testing adherence.In a population with primarily irregular screening participation,tests with the highest point sensitivity and reasonable specificity are more likely to favorably impact CRC related morbidity and mortality than those depending on annual adherence.This paper reviews the evidence supporting mt-s DNA for routine screening and demonstrates,using USPSTF's modeling data,that mt-s DNA at three-year intervals provides significant clinical net benefits and fewer complications per LYG than annual fecal immunochemical testing,high sensitivity guaiac based fecal occult blood testing and 10-year colonoscopy screening.
基金Supported by Health Sciences Research Grants(Comprehensive Research on Life-Style Related Diseases including Cardiovascular Diseases and Diabetes Mellitus No.H25-016)from the Ministry of HealthLabour and Welfare of Japanand supported in part by Grants-in-Aid for Research from the National Center for Global Health and Medicine No.26A-201
文摘AIM: To determine the bowel symptoms associated with diabetes and diabetes-related factors after excluding gastrointestinal (GI) organic diseases.METHODS: Participants were 4738 (603 diabetic and 4135 non-diabetic) patients who underwent colonoscopy and completed a questionnaire. On the day of pre-colonoscopy, 9 symptoms (borborygmus, abdominal distension, increased flatus, constipation, diarrhea, loose stools, hard stools, fecal urgency, and incomplete evacuation) were prospectively evaluated on a 7-point Likert scale. The test-retest reliability of the bowel symptom scores from the baseline and second questionnaires was analyzed using kappa statistics. Associations between bowel symptom scores and diabetes or diabetes-related factors were analyzed by a rank-ordered logistic model adjusted for related confounders, and odds ratios (ORs) were estimated.RESULTS: In multivariate analysis, constipation [adjusted odds ratio (AOR) = 1.57, CI: 1.33-1.85, P < 0.01] and hard stools (AOR = 1.56, CI: 1.33-1.84, P < 0.01) were associated with diabetes, and fecal urgency (AOR = 1.16, CI: 0.99-1.37, P = 0.07) and incomplete evacuation (AOR = 1.16, CI: 1.00-1.36, P = 0.06) were marginally associated with diabetes. These symptoms remained associated even after excluding organic GI diseases on colonoscopy. Test-retest reliability of symptom score with a mean duration of 3.2 mo was good (mean kappa, 0.69). Associations of symptoms with diabetes-related factors were found; constipation with HbA1c ≥ 8.0% (AOR = 2.11, CI: 1.19-3.73), body mass index (BMI) < 25 (AOR = 2.11, CI: 1.22-3.66), and insulin use (AOR = 1.90, CI: 1.08-3.36); hard stools with diabetes duration (AOR = 1.03, CI: 1.00-1.07); fecal urgency with BMI < 25 (AOR = 1.73, CI: 1.00-2.98); and incomplete evacuation with BMI < 25 (AOR = 2.60, CI: 1.52-4.43), serum creatinine level (AOR = 1.27, CI: 1.10-1.47), and insulin use (AOR = 1.92, CI: 1.09-3.38).CONCLUSION: Diabetes is associated with constipation, hard stools, fecal urgency, and incomplete evacuation, and poor glycemic control, duration, leanness, and nephropathy affect the risk of these symptoms.
基金supported by a research grant from the Office of the Vice-Chancellor for Research and Development,University of the Philippines-Diliman(Grant No.101007 PNSE)to W.L.R.and H.J.S
文摘Objective:To compare the sensitivity and specificity of direct fecal smear microscopy,culture,and polymerase chain reaction in the detection of Blastocystis sp.in human stool.Methods:Human stool samples were collected from a community in San Isidro,Rodriguez,Rizal,Philippines.These samples were subjected to direct fecal smear microscopy,culture and polymerase chain reaction to detect the presence of Blastocystis sp.Results:Of the 110 stool samples collected,28(25%)were detected positive for the presence of Blastocystis sp.by two or more tests.Culture method detected the highest number of Blastocystis-positive stool samples(n=36),followed by PCR of DNA extracted from culture(n=26),PCR of DNA extracted from stool(n=10),and direct fecal smear(n=9).Compared to culture,the sensitivity of the other detection methods were 66.7%for PCR from culture and 19.4%for both PCR from stool and direct fecal smear.Specificity of the methods was high,with PCR from culture and direct fecal smear having97.3%,while PCR from stool at 95.9%.Conclusions:In this study,in vitro culture is the best method for detecting Blastocystis sp.in human stool samples.
文摘Objective: Despite the high prevalence of CRC and the proven benefits of faecal sampling tests, participation rates in CRC screening are suboptimal. Literature has identified a number of barriers to participation, including faecal aversion. Emerging test technologies suggest blood-based molecular markers might provide an alternative, more acceptable option, for CRC screening tests. We aim to determine preference for blood compared to faeces as the sample for the screening test. Methods: A survey was mailed to 956 South Australians aged 50 to 74 years. Data were collected on sample preference, demographic variables, and ratings of screening test convenience and comfort. Results: The survey yielded a 43% response rate. The majority of participants preferred to provide a blood sample (78% v 22%, p < 0.001). Women were more likely to prefer blood than men (82% vs 74%, p = 0.05). Sample experience influenced preferences, with a significantly higher preference for faeces among participants with experience in faecal sampling (27% vs 17% with no experience, p < 0.05). Participants who preferred to provide a faecal sample rated it significantly more convenient (p < 0.001), more comfortable (p < 0.001), and more acceptable (p < 0.001) than those who preferred blood sampling. Conclusions: Survey participants overwhelmingly indicate a preference for the idea of a blood sample over a faecal sample for CRC screening. Preference was influenced by gender, experience with sampling method and the individual’s perception of sampling convenience, sampling comfort and sample acceptability. Our results suggest population participation rates are likely to improve with blood-based screening tests.
基金Supported by The Islamic Azad University,Shahre Kord Branch-Iran grant 89/8761
文摘AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens,CONCLUSION:Regard to high similarity in genotype of H.pylori isolates from saliva,stomach and stool,this study support the idea which fecal-oral is the main route of H.pylori transmission and oral cavity may serve as a reservoir for H.pylori,however,remarkable genotype diversity among stomach,saliva and stool samples showed that more than one H.pylori genotype may exist in a same patient.
文摘AIM To determine the uptake of noninvasive multitarget stool DNA (mt-s DNA) in a cohort of colorectal cancer(CRC) screening non-compliant average-risk Medicare patients.METHODS This cross sectional primary care office-based study examined mt-s DNA uptake in routine clinical practice among 393 colorectal cancer screening non-compliant Medicare patients ages 50-85 ordered by 77 physicians in a multispecialty group practice (USMD Physician Services, Dallas, TX) from October, 2014-September, 2015. Investigators performed a Health Insurance Portability and Accountability Act compliant retrospective review of electronic health records to identify mt-s DNA use in patients who were either > 10 years since last colonoscopy and/or > 1 year since last fecal occult blood test. Test positive patients were advised to get diagnostic colonoscopy and thereafter patients were characterized by the most clinically significant lesion documented on histopathology of biopsies or excisional tissue. Descriptive statistics were employed. Key outcome measures included mt-s DNA compliance and diagnostic colonoscopy compliance on positive cases.RESULTS Over 12 mo, 77 providers ordered 393 mt-sD NA studies with 347 completed (88.3% compliance). Patient mean age was 69.8 (50-85) and patients were 64% female. Mt-sD NA was negative in 85.3%(296/347) and positive in 14.7%(51/347). Follow-up colonoscopy was performed in 49 positive patients (96.1% colonoscopy compliance) with two patients lost to follow up. Index findings included: colon cancer(4/49, 8.2%), advanced adenomas (21/49, 42.9%), non-advanced adenomas(15/49, 30.6%), and negative results (9/49, 18.4%). The positive predictive value for advanced colorectal lesions was 51.0% and for any colorectal neoplasia was 81.6%. The mean age of patients with colorectal cancer was 70.3 and all CRC's were localized Stage Ⅰ(2) and Stage Ⅱ (2), three were located in the proximal colon and one was located in the distal colon.CONCLUSION Mt-s DNA provided medical benefit to screening noncompliant Medicare population. High compliance with mt-s DNA and subsequent follow-up diagnostic colonoscopy identified patients with clinically critical advanced colorectal neoplasia.
文摘AIM To study cancer hotspot mutations by next-generation sequencing(NGS) in stool DNA from patients with different gastrointestinal tract(GIT) neoplasms. METHODS Stool samples were collected from 87 Finnish patients diagnosed with various gastric and colorectal neoplasms, including benign tumors, and from 14 healthy controls. DNA was isolated from stools by usingthe PSP~? Spin Stool DNA Plus Kit. For each sample, 20 ng of DNA was used to construct sequencing libraries using the Ion AmpliS eq Cancer Hotspot Panel v2 or Ion AmpliS eq Colon and Lung Cancer panel v2. Sequencing was performed on Ion PGM. Torrent Suite Software v.5.2.2 was used for variant calling and data analysis.RESULTS NGS was successful in assaying 72 GIT samples and 13 healthy controls, with success rates of the assay being78% for stomach neoplasia and 87% for colorectal tumors. In stool specimens from patients with gastric neoplasia, five hotspot mutations were found in APC,CDKN2 A and EGFR genes, in addition to seven novel mutations. From colorectal patients, 20 mutations were detected in AKT1, APC, ERBB2, FBXW7, KIT, KRAS,NRAS, SMARCB1, SMO, STK11 and TP53. Healthy controls did not exhibit any hotspot mutations, except for two novel ones. APC and TP53 were the most frequently mutated genes in colorectal neoplasms, with five mutations, followed by KRAS with two mutations.APC was the most commonly mutated gene in stools of patients with premalignant/benign GIT lesions.CONCLUSION Our results show that in addition to colorectal neoplasms,mutations can also be assayed from stool specimens of patients with gastric neoplasms.
文摘A comparative study was performed to evaluate best practice culture media and enrichment broths for recovering Salmonella species from human stool samples. A total of 1297 human stools were collected and processed in this study. Evaluation of agar media was carried out by direct plating (DP), 1096 stool samples were inoculated on Modified Semisolid Rappaport-Vassiliadis (MSRV), Xylose-Lysine-Deoxycolate (XLD), MacConkey (MAC), and Hektoen Enteric (HE) agars. Evaluation of enrichment broths were carried out by enrichment all 1297 stool samples in Selenite broth (SB), Rappaport-Vassiliadis (RV) broth, and Buffered Peptone Water (BPW), followed by plating on MSRV, MAC, and HE agars. A total of 102 Salmonella-positive stools by DP, 85.3% (87/102) were recovered utilizing MSRV while recovery from XLD, MAC, and HE agars were 34.3% (35/102), 34.3% (35/102), and 29.4% (30/102) respectively. A total 299/1297 stools samples were Salmonella-positive on at least one plating medium after enrichment procedure were 77.3% (177/299) for SB, 86.0% (197/299) and 78.6% (180/299) for RV and BPW respectively. All Salmonella isolated in this study was nontyphi Salmonella. Presently, the data suggest that the use of MSRV over MAC, HE, and XLD agars for isolation nontyphi Salmonella species from human stools is more efficacious. Additionally, use of MSRV in combination with MAC and HE agars following enrichment in RV broth enhances recovery of nontyphi Salmonella species. However, RV broth is inhibitory to typhi Salmonella, thus use of MSRV medium in combination with MAC, HE or XLD agars in direct plating following enrichment in non-selective BPW is an alternate method for recovery of both typhi and nontyphi Salmonella species contaminated in human stool samples.
文摘Introduction and Objective: The genus Bifidobacterium can generally be found in quantity in the habitats such as human and animal gastrointestinal tract, dental caries, vagina and oral cavity. The aim of this study was to isolate Bifidobacterium from stool and determine their inhibitory effect against some pathogens. Materials and Methods: 130 samples were collected by wet swabs and kept in sterile tubes containing MRS broth media. And Bifidobacterium isolated from stool was enriched in Man-Rogosa-Sharpe medium (MRS) broth and isolated by growing on MRS agar medium and characterized by phenotypic characteristics and PCR technique at genus and species levels. The antimicrobial substance was extracted from ethyl acetate solvent and the antimicrobial activity against some pathogenic bacteria, such as Salmonella typhi and Shigella sonnei, were investigated. Results: Eleven Bifidobacterium bifidum and four Bifidobacterium adolescentis, which were isolated from fresh stool, were identified by PCR. Antimicrobial substance from MRS broth medium was extracted. This antimicrobial compound showed a potent inhibitory activity against four tested bacteria. These bacteria produced acetic acid and lactic acid as inhibitory substances that were different from bacteriocins. Conclusion: Fresh stool may be used as a source of antimicrobial lactic acids bacteria, Bifidobacterium bifidum and adolescentis as two probiotics can establish themselves in gut and urogenital tract to prevent the human body from adverse effects of pathogens.
基金Supported by the Medical and Health Research Project of Zhejiang Province,No.2021KY1048 and 2022KY1142Ningbo Health Young Technical Backbone Talents Training Program,No.2020SWSQNGG-02the Key Science and Technology Project of Ningbo City,No.2021Z133.
文摘BACKGROUND Colorectal cancer(CRC)is a major global health burden.The current diagnostic tests have shortcomings of being invasive and low accuracy.AIM To explore the combination of intestinal microbiome composition and multi-target stool DNA(MT-sDNA)test in the diagnosis of CRC.METHODS We assessed the performance of the MT-sDNA test based on a hospital clinical trial.The intestinal microbiota was tested using 16S rRNA gene sequencing.This case-control study enrolled 54 CRC patients and 51 healthy controls.We identified biomarkers of bacterial structure,analyzed the relationship between different tumor markers and the relative abundance of related flora components,and distinguished CRC patients from healthy subjects by the linear discriminant analysis effect size,redundancy analysis,and random forest analysis.RESULTS MT-sDNA was associated with Bacteroides.MT-sDNA and carcinoembryonic antigen(CEA)were positively correlated with the existence of Parabacteroides,and alpha-fetoprotein(AFP)was positively associated with Faecalibacterium and Megamonas.In the random forest model,the existence of Streptococcus,Escherichia,Chitinophaga,Parasutterella,Lachnospira,and Romboutsia can distinguish CRC from health controls.The diagnostic accuracy of MT-sDNA combined with the six genera and CEA in the diagnosis of CRC was 97.1%,with a sensitivity and specificity of 98.1%and 92.3%,respectively.CONCLUSION There is a positive correlation of MT-sDNA,CEA,and AFP with intestinal microbiome.Eight biomarkers including six genera of gut microbiota,MT-sDNA,and CEA showed a prominent sensitivity and specificity for CRC prediction,which could be used as a non-invasive method for improving the diagnostic accuracy for this malignancy.
文摘BACKGROUND Recently,stool multiplex polymerase chain reaction(PCR)tests have been developed for identifying diarrhea-causing bacterial pathogens.Furthermore,fecal calprotectin is a well-known effective marker for intestinal mucosal inflammation.AIM To evaluate the efficacy of stool multiplex PCR and fecal calprotectin in acute infectious diarrhea.METHODS Overall,400 patients with acute infectious diarrhea were enrolled from Kangdong Sacred Heart Hospital(January 2016 to December 2018).Multiplex PCR detected 7 enteropathogenic bacteria including Salmonella,Campylobacter,Shigella,Escherichia coli O157:H7,Aeromonas,Vibrio,and Clostridium difficile.We reviewed clinical and laboratory findings using stool multiplex PCR.RESULTS Stool multiplex PCR test detected considerably more bacterial pathogens than stool culture(49.2%vs 5.2%),with Campylobacter as the most common pathogen(54%).Patients with positive stool PCR showed elevated fecal calprotectin expression compared to patients with negative stool PCR(1124.5±816.9 mg/kg vs 609±713.2 mg/kg,P=0.001).C-reactive protein(OR=1.01,95%CI:1.001-1.027,P=0.034)and sigmoidoscopy-detected colitis(OR=4.76,95%CI:1.101-20.551,P=0.037)were independent factors in stool PCR-based detection of bacterial pathogens.Sensitivity and specificity of calprotectin were evaluated to be 70.5%and 60.9%,respectively(adjusted cut-off value=388 mg/kg).CONCLUSION Stool multiplex PCR test has increased sensitivity in detecting pathogens than conventional culture,and it is correlated with calprotectin expression.Stool multiplex PCR and calprotectin may be effective in predicting clinical severity of infectious diarrhea.
基金Supported by“Fondo de Investigaciones Sanitarias(FIS)-FEDER”,Ministry of Health,Spain,No.PI13/01924 to García-Olmo DRETIC Program of ISCIII-FEDER,No.RD12/0019/0035 to Olmedillas-López S
文摘AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients with stage I-IV CRC diagnosed by preoperative biopsy. KRAS mutational status was determined by pyrosequencing analysis of DNA obtained from formalin-fixed paraffin-embedded (FFPE) tumor tissues. The KRAS G12D mutation was then analyzed by ddPCR in FFPE tumors and stool-derived DNA from patients with this point mutation. Wild-type (WT) tumors, as determined by pyrosequencing, were included as controls; analysis of FFPE tissue and stool-derived DNA by ddPCR was performed for these patients as well.RESULTSAmong the total 70 patients included, KRAS mutations were detected by pyrosequencing in 32 (45.71%), whereas 38 (54.29%) had WT tumors. The frequency of KRAS mutations was higher in left-sided tumors (11 located in the right colon, 15 in the left, and 6 in the rectum). The predominant point mutation was KRAS G12D (14.29%, n = 10), which was more frequent in early-stage tumors (I-IIA, n = 7). In agreement with pyrosequencing results, the KRAS G12D mutation was detected by ddPCR in FFPE tumor-derived DNA, and only a residual number of mutated copies was found in WT controls. The KRAS G12D mutation was also detected in stool-derived DNA in 80% of all fecal samples from CRC patients with this point mutation.CONCLUSIONddPCR is a reliable and sensitive method to analyze KRAS G12D mutation in stool-derived DNA from CRC patients, especially at early stages. This non-invasive approach is potentially applicable to other relevant biomarkers for CRC management.
文摘AIM： To evaluate the agreement between a mAb-based stool test （HP STAR） and the urea breath test （UBT） in monitoring （H pylon） infection after eradication therapy. METHODS： Patients with discordant results on UBT and Hp STAR underwent endoscopy with biopsies for rapid urease test, culture, and histology to confirm H pylori status. RESULTS： Among 250 patients （50±14 years）, 240 （96.0%） had concordant UBT and Hp STAR tests with a significant correlation between DOB and A values （R = 0.87; P〈0.0001）. The remaining 10 （4.0%） patients had discordant tests （positive Hp STAR and negative UBT） with the Hp STAR inaccurate in five cases （false positive） and UBT inaccurate in the other five cases （false negative）. The “maximal expected” sensitivity, specificity, ＋PV, -PV, ＋LR, and -LR were 91%, 100%, 100%, 97.4%, ∞, and 8.2 respectively, for the UBT, and 100%, 97.4%, 91%, 100%, 38.8, and 0, respectively, for the Hp STAR. Overall accuracy for both tests was 98%. CONCLUSION： Both the UBT and the Hp StAR are equally accurate in monitoring H pylori infection. Nowadays, the choice of the “best” non-invasive H pylori test in the post-treatment setting should be done not only in terms of diagnostic accuracy but also in view of cost and local facilities.
