Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “fecal sample”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

Prevalence of vancomycin-resistant enterococci in fecal samples from hospitalized patients and nonhospitalized controls in a cattle-rearing area of France.

Vancomycin-resistant enterococci (VRE) have emerged as nosocomial pathogens over the last decade, but little is known about their epidemiology. We report on the prevalence of VRE fecal colonization on the basis of a prospective study among patients hospitalized in a hematology intensive care unit and among nonhospitalized subjects living in the local community. A total of 243 rectal swabs from hematology patients and 169 stool samples from the control group were inoculated onto bile-esculin agar plates with and without 6 mg of vancomycin per liter and into an enrichment bile-esculin broth supplemented with 4 mg of vancomycin per liter. A total of 37% of the hospitalized patients and 11.8% of the subjects from the community were found to be VRE carriers. A total of 65 VRE strains were isolated: 12 (18.5%) E. faecium, 46 (70.7%) E. gallinarum, and 7 (10.8%) E. casseliflavus strains. No E. faecalis strains were detected. All the E. faecium strains were of the vanA genotype. Molecular typing by pulsed-field gel electrophoresis revealed a different pattern for each vanA VRE strain that originated from an individual subject. To our knowledge, this is the first study to be carried out in a cattle-rearing region of France. It reports a higher VRE prevalence than that reported in previous European or U.S. studies. A partial explanation is the use of an enrichment broth step which enabled detection of strains which would otherwise have been missed, but the fact that subjects and patients were recruited from a predominantly agricultural area where vancomycin-related antibiotics have recently been used in animal husbandry could also contribute to the high levels of VRE in patients and subjects alike.

Adolescent↗

R-Plasmid Transfer to and from Escherichia coli Strains Isolated from Human Fecal Samples.

Strains of Escherichia coli recently isolated from human feces were examined for the frequency with which they accept an R factor (R1) from a derepressed fi strain of E. coli K-12 and transfer it to fecal and laboratory strains. Colicins produced by some of the isolates rapidly killed the other half of the mating pair; therefore, conjugation was conducted by a membrane filtration procedure whereby this effect was minimized. The majority of fecal E. coli isolates accepted the R factor at lower frequencies than K-12 F, varying from 10 per donor cell to undetectable levels. The frequencies with which certain fecal recipients received the R-plasmid were increased when its R transconjugant was either cured of the R1-plasmid and remated with the fi strain or backcrossed into the parental strain. The former suggests the loss of an incompatibility plasmid, and the latter suggests the modification of the R1-plasmid deoxyribonucleic acid (DNA). In general, the fecal RE. coli transconjugants were less effective donors for K-12 F and heterologous fecal strains than was the fi K-12 strain, whereas the single strain of Citrobacter freundii examined was generally more competent. Passage of the R1-plasmid to strains of salmonellae reached mating frequencies of 10 per donor cell when the recipient was a Salmonella typhi previously cured of its resident R-plasmid. However, two recently isolated strains of Salmonella accepted the R1-plasmid from E. coli K-12 R or the RE. coli transconjugants at frequencies of 5 x 10 or less.

Journal Article↗

Cost-effectiveness analysis of immunochemical occult blood screening for colorectal cancer among three fecal sampling methods.

BACKGROUND/AIMS: To evaluate the optimal sampling times of stool in immunochemical occult blood screening from the viewpoint of the cost-effectiveness. METHODOLOGY: A colorectal cancer screening was conducted in 5 municipalities (Matsumoto, Hata, Yamagata, Asahi, Sakai), Nagano prefecture, Japan in 1996. Each participant received a fecal occult blood test with 3 consecutive days. For the economic assessment of testing methods, the results of the 1st day, those of the 1st and 2nd days and those of the 3 consecutive days were used for a single-day method, a 2-day method, and a 3-day method. The average costs per detection of one cancer patient and diagnostic validity were evaluated among 3 months. RESULTS: The average costs for one cancer case detected were calculated to be $5924 for a single-day method, $6014 for a 2-day method, and $7123 for a 3-day method, respectively. The sensitivity and specificity were calculated to be 58% and 96% for a single-day method, 89% and 95% for a 2-day method, and 100% and 94% for a 3-day method, respectively, indicating a significant difference in the sensitivity between a single-day method and a 2-day as well as a 3-day method (P < 0.05), and in the specificity among 3 testing methods (P < 0.001). CONCLUSIONS: The present analysis suggests that a 2-day collection method is recommended in the immunochemical occult blood screening from the viewpoint of the cost-effectiveness as well as the diagnostic accuracy.

Adult↗

Evaluation of fecal samples from mares as a source of Rhodococcus equi for their foals by use of quantitative bacteriologic culture and colony immunoblot analyses.

OBJECTIVE: To determine whether mares are a clinically important source of Rhodococcus equi for their foals. SAMPLE POPULATION: 171 mares and 171 foals from a farm in Kentucky (evaluated during 2004 and 2005). PROCEDURES: At 4 time points (2 before and 2 after parturition), the total concentration of R equi and concentration of virulent R equi were determined in fecal specimens from mares by use of quantitative bacteriologic culture and a colony immunoblot technique, respectively. These concentrations for mares of foals that developed R equi-associated pneumonia and for mares with unaffected foals were compared. Data for each year were analyzed separately. RESULTS: R equi-associated pneumonia developed in 53 of 171 (31%) foals. Fecal shedding of virulent R equi was detected in at least 1 time point for every mare; bacteriologic culture results were positive for 62 of 171 (36%) mares at all time points. However, compared with dams of unaffected foals, fecal concentrations of total or virulent R equi in dams of foals with R equi-associated pneumonia were not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that dams of foals with R equi-associated pneumonia did not shed more R equi in feces than dams of unaffected foals; therefore, R equi infection in foals was not associated with comparatively greater fecal shedding by their dams. However, detection of virulent R equi in the feces of all mares during at least 1 time point suggests that mares can be an important source of R equi for the surrounding environment.

Actinomycetales Infections↗

Molecular and microscopic techniques for detection of Sarcocystis neurona sporocysts in fecal samples.

Diagnosis of Sarcocystis sp. in the definitive host is generally by microscopic detection of the sporocysts in feces. This method is insensitive and cannot differentiate between species because sporocysts lack specific staining criteria. The hypothesis suggested that molecular techniques provide better alternatives to classical detection of Sarcocystis sporocysts. The sensitivity of two PCR assays was compared to one another and to microscopic examination by conventional fecal flotation and Diamant-Fuchsin staining procedures for detection of sporocysts spiked into mice feces. PCR1 assay using LSM1 & LSM2 primers that amplified 496 bp of the ssurRNA gene was more sensitive than the PCR2 method using JNB25 and JD396 primers that amplified 334 bp of a RAPD-derived marker. PCRI gave positive results with 200 microl of fecal suspension spiked with as little as 5 sporocysts compared to 75 sporocysts detected by JNB25 & JD396 primers. PCRI was more sensitive than conventional microscopy. PCR1 or PCR2 followed by sequencing or RFLP analysis not only detected Sarcocystis sporocysts in feces but also enabled to ascertain the genotype of the species as S. neurona.

Animals↗

Short report: polymerase chain reaction detection of hepatitis E virus in north African fecal samples.

Epidemics of enterically-transmitted non-A, non-B hepatitis were described in 1983-1984 involving French soldiers in Chad and in 1979-1980 in residents of Algeria. Hepatitis E virus (HEV) was subsequently implicated by serology. In this study, the presence of HEV in patient stool specimens from both outbreaks and from sporadic cases in residents of Chad (1994) was documented. This virus was detected in fecal suspensions by antibody capture of the virus and reverse transcriptase-polymerase chain reaction amplification of the viral RNA in the 3' end of open reading frame 2. Two of five epidemic cases from Chad (1983-1984) were positive, as well as one of five sporadic cases from Chad (1994), and two of three epidemic cases from Algeria (1979-1980). Of these 13 patients, 12 had detectable anti-HEV IgG in their serum. These results confirmed that HEV was the cause of hepatitis in at least five of these 13 patients.

Africa, Northern↗

Development of strain-specific PCR reactions for the detection of the probiotic Escherichia coli strain Nissle 1917 in fecal samples.

PCR was used to establish a specific detection system for the non-pathogenic Escherichia coli strain Nissle 1917 (DSM6601), which is used as a probiotic drug against intestinal disorders and diseases. Five PCR assays have been developed which are based on the chromosomally encoded major fimbrial subunit genes fimA (type 1 fimbriae) and focA (F1C fimbriae), and the two small cryptic plasmids pMUT1 and pMUT2. The assays were validated by testing a collection of 354 different pathogenic and non-pathogenic E. coli strains from various origins, including E. coli K-12, fecal and environmental as well as pathogenic extraintestinal and intestinal E. coli strains. The most specific results were obtained with primers based on DNA sequences from plasmid pMUT2. The plasmid-based PCR assays described can be used to detect E. coli strain Nissle 1917 in feces from patients without prior cultivation.

DNA Primers↗

Evaluation of a commercial latex agglutination test for rapid detection of Salmonella in fecal samples.

A latex agglutination test for the detection of salmonella in feces was evaluated in comparison to direct culture and enriched culture using both artificially inoculated samples and clinical samples. In the samples inoculated artificially with different concentrations of salmonella (10(1) to 10(5) per gram) the enriched culture performed better only at the 10(2) level in 0.4 g samples, whereas the latex test performed as well as the enriched culture at all levels in 4 g samples. In the tests using clinical samples, there was no significant difference between results of the latex test performed in 2283 samples and the enriched culture performed in 2072 samples. The sensitivity, specificity and negative and positive predictive values of the latex test were 88.2%, 98%, 97.5% and 63% respectively. The test provided results rapidly but yielded a number of false positive results.

Bacteriological Techniques↗

A new method for isolation and differentiation of native Entamoeba histolytica and E. dispar cysts from fecal samples.

A new method for the purification of protozoan cysts from feces was established, allowing to isolation of native cysts. The procedure consists of two sucrose-density gradients and enzymatic digestion of cellulose particles by cellulase and can be accomplished in a few hours. The cyst fractions were differentiated into Entamoeba histolytica and E. dispar using the DNA probes P145 and B133 and a dot-blot test.

Animals↗

Evaluation of a commercial enzyme immunoassay for the detection of norovirus antigen in fecal samples from children with sporadic acute gastroenteritis.

The Ridascreen Norwalk-like virus enzyme immunoassay was compared with (RT)-PCR on 92 stool samples collected from children with sporadic acute gastroenteritis. Homogenization and pre-dilution of the whole stool sample resulted in high specificity (97.5%) and moderate sensitivity (60%). This assay may be useful to screen outbreaks for norovirus, but limited to detect the virus in sporadic cases of diarrhea.

Antigens, Viral↗

Strategies for the inclusion of an internal amplification control in conventional and real time PCR detection of Campylobacter spp. in chicken fecal samples.

To illustrate important issues in optimization of a PCR assay with an internal control four different primer combinations for conventional PCR, two non-competitive and two competitive set-ups for real time PCR were used for detection of Campylobacter spp. in chicken faecal samples. In the conventional PCR assays the internal control was genomic DNA from Yersinia ruckeri, which is not found in chicken faeces. This internal control was also used in one of the set ups in real time PCR. In the three other set-ups different DNA fragments of 109 bp length prepared from two oligos of each 66 bp by a simple extension reaction was used. All assays were optimized to avoid loss of target sensitivity due to the presence of the internal control by adjusting the amount of internal control primers in the duplex assays and the amount of internal control in all assays. Furthermore, the assays were tested against faecal inhibitors to ensure that the internal control and the target PCR had the same sensitivity towards inhibitors.

Animals↗

Detection of Escherichia coli Shiga toxin (stx) and enterotoxin (estA and elt) genes in fecal samples from non-diarrheic and diarrheic greyhounds.

Virulence factors responsible for acute diarrhea in greyhounds have not been well established. The objective of this study was to determine if a correlation exists between disease and the presence of the Escherichia coli toxin genes in non-diarrheic and diarrheic greyhound feces. DNA extracted from broth cultures was evaluated for the presence of Shiga toxin and enterotoxin genes and broth samples were evaluated for Shiga toxin and heat-labile enterotoxin. Shiga toxin (stx1 and stx2) and enterotoxin (et and estA) genes were identified in both non-diarrheic and diarrheic samples after in vitro cultured of swabs at 37 degrees C for 16-24h. The stx1 gene was present in 3% of non-diarrheic and 15% diarrheic samples and the stx2 gene was identified in 36 and 23%, non-diarrheic and diarrheic samples, respectively. Shiga toxin was present in 48% diarrheic and 25% of the non-diarrheic in vitro cultured samples. The elt gene was detected in vitro cultured swabs in 12% of the non-diarrheic and 7% of the diarrheic samples. Labile toxin was present in the feces of small numbers of both groups of dogs. A significant correlation existed between the presence of both stx1 genes and Shiga toxin in feces, and lack of disease in non-diarrheic (P=0.01) and presence of disease in diarrheic (P=0.024) greyhounds. Correlation between production of Shiga toxin and detection of stx1 or stx2 was significant in both the diarrheic and non-diarrheic feces (P=0.03); however, only the presence of stx1 correlated with diarrhea in both groups of samples (P<0.008). The incidence of toxigenic E. coli in both non-diarrheic and diarrheic greyhounds indicates a zoonotic potential from dogs to humans and requires further study.

Acute Disease↗

Occurrence of Clostridium difficile in fecal samples of HIV-infected children in Poland.

The prevalence of Clostridium difficile and its toxins (A and B) in HIV-positive children in Poland was investigated in a group of 18 children, aged 6 months to 8 1/2 years. Stool samples were tested using an antigen detection method for toxin A/B, cytotoxicity-neutralization and culture. In 3 cases (17%) C. difficile toxins were detected in both stool samples and strains recovered from culture. The three strains isolated were shown by PCR methods to contain toxins A and B genes. All children had been treated previously with antimicrobial and antiviral agents. All three C. difficile-positive children had mild diarrhea that resolved without specific therapy. Further studies involving a large number of children and molecular analyses of isolated C. difficile strains are necessary to determine the frequency and rate of carriage of C. difficile strains among HIV-positive children in Poland.

Journal Article↗

A kinetic study in adults with food hypersensitivity assessed as eosinophil activation in fecal samples.

BACKGROUND: Immune-mediated food hypersensitivity affecting the gut is difficult to evaluate, and objective tools to diagnose local gastrointestinal (GI) inflammatory reactions are lacking. OBJECTIVES: To determine whether allergic manifestations in adults with a history of food-related GI symptoms could be assessed in feces during symptomatic and non-symptomatic periods, using the surrogate markers, eosinophil cationic protein (ECP), eosinophil protein X (EPX) and myeloperoxidase (MPO). METHODS: Thirteen subjects with food hypersensitivity-related GI symptoms, confirmed by a positive double-blind placebo-controlled food challenge (DBPCFC), were subjected to an open kinetic food challenge design for 6 weeks. Symptoms were recorded and scored during the 3-week study period and stool samples were obtained every day. The surrogate markers ECP, EPX and MPO were measured in the supernatants from feces samples. RESULTS: A significant increase in abdominal pain, distension and flatulence was observed during challenge, with a gradual decrease during elimination diet. Both between days and subjects, EPX levels were more frequently increased compared to ECP and MPO. Individuals with a history of a short duration of symptoms had significantly higher mean levels of EPX and MPO than those with a longer duration of symptoms. CONCLUSIONS: An overall increase in levels of eosinophil markers, in particular EPX, was observed in feces from patients with food-related GI symptoms. However, rather than being a tool to differentiate symptomatic from non-symptomatic periods, EPX might be used for detecting an ongoing clinical or subclinical chronic inflammation, that may have an impact on the patient's clinical course of GI symptoms.

Adult↗

[Surveillance of group illnesses with Norwalk-like viruses (NLV) in Baden-Württemberg. Isolation and detection of Norwalk-like viral RNA from fecal samples with RT-PCR].

Between the turn of the years 98/99 and 99/2000, stool samples from various health departments in the south of Germany were sent to the LGA (Landesgesundheitsamt Baden-Württemberg). Different testings as bacteriological routines for enterobacteriaceae and virological antigen screenings of the stool samples for adeno-, astro- and rotaviruses lead to negative results. Additional RT-PCR tests for the presence of Norwalk-RNA showed nearly 40% of positive samples. From 14 group infections between december 98 and january 2000, 286 samples in total were sent to the LGA, 118 of them gave positive results for the norwalk agent. For the verification of the analysis, some random samples were sent to the Robert-Koch-Institut, div. of molecular virology at Berlin, where the results were confirmed.

Caliciviridae Infections↗