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M Delmée

Publications and source records attributed to M Delmée.

At least 37 records · Page 2Linked to original sources
PubMed1998

A multicentre survey of antimicrobial resistance in gram-negative isolates from Belgian intensive care units in 1994-1995. Belgian Multicenter ICU Study Group.

The aim of this prospective study was to evaluate the distribution and antibiotic susceptibility of aerobic Gram-negative bacilli isolated from patients in intensive care units in 18 Belgian hospitals during 1994 and 1995. A standardised method (i.e. the E-test) was used in each center to determine the minimum inhibitory concentrations of 12 major antibiotics against 1435 consecutive, non duplicate, Gram-negative isolates (close to 100 strains per hospital) during a period of 6 months. The isolates were mainly isolated from the lower respiratory tract (57.4%), urinary tract (17.7%), pus (7.9%) or blood specimens (7.8%) and were mainly P.aeruginosa (20.3%), E.coli (19.9%) and Enterobacter spp. (12.6%). Overall inducible Enterobacteriaceae (IE) accounted for 29.8% of all isolates, and E.aerogenes was the most frequently isolated species in this group (27.6%). The overall susceptibility rate (all species confounded) was about 70% to piperacillin, ticarcillin-clavulanic acid and ceftriaxone, 78% to piperacillin-tazobactam; 87% both to ceftazidime and to ciprofloxacin; and 90% to imipenem. Widespread resistance was observed in several IE species to third generation cephalosporins, broad-spectrum penicillins and to ciprofloxacin. By contrast, imipenem and the aminoglycosides still retained excellent activity against most multiresistant species. Although there were wide differences between hospitals in the frequencies of resistance to most antibiotics, these were not related to the types (general vs. university) of hospitals or to the number of beds. Some variations were however observed in the distribution of bacterial species: the prevalence of inducible Enterobacteriaceae was significantly higher in university than in general hospitals and in hospitals located in Brussels and in Wallonia than in the Flanders. Overall few trends in resistance rates were observed in comparison to a similar survey performed in 1991.

Cross Reactions↗
PubMed1998

Surveillance of human Yersinia enterocolitica infections in Belgium: 1967-1996.

Between 1967 and 1996, > 18,700 strains of Yersinia species, excluding Yersinia pestis, were recovered in Belgium from a variety of gastrointestinal and extraintestinal sites in patients. Full identification and serotyping were performed by the two Belgian reference laboratories. Yersinia enterocolitica serogroup O:3 predominated (79.4% of strains), followed by serogroup O:9 (11.1%). The remaining 9.5% of isolates belonged to serogroups and related species generally considered nonpathogenic. Acute enterocolitis was the most common clinical form of Y. enterocolitica infection, affecting primarily children younger than 5 years of age. Since 1967, there was a steady increase in isolations every year, with 305 cases in 1975 and up to 1,469 in 1986. From 1987 on, there was a clear decrease in the number of reported cases, although the number of participating laboratories and culture techniques remained constant. This significant decrease in the occurrence of Y. enterocolitica infections may be explained by changes in the slaughtering procedures and eating habits of the population.

Adolescent↗
PubMed1998

A novel toxinotyping scheme and correlation of toxinotypes with serogroups of Clostridium difficile isolates.

Two hundred nineteen Clostridium difficile isolates from 22 serogroups were screened for changes in the genes coding for toxin B (tcdB) and toxin A (tcdA). Parts of the toxin genes were amplified, and the PCR fragments were checked for length polymorphisms and cut with several restriction enzymes to monitor restriction fragment length polymorphisms (RFLPs). For 47 strains (21%), differences in the toxin genes were found compared to the toxin genes of reference strain VPI 10,463. Polymorphisms were usually observed in both toxin genes. RFLPs were more commonly found in the tcdB gene, in which a single restriction enzyme could give up to five different patterns. Restriction sites seemed to be less heterogeneous in the tcdA gene, in which for most enzymes only two different RFLPs were recognized. However, deletions were observed in tcdA, and four new types of shortened tcdA genes are described. According to the changes in their toxin genes, variant strains could be divided into 10 groups (toxinotypes I to X). A toxinotype was characterized by similar patterns of changes in the toxin genes and in other regions of the pathogenicity locus and also similar pulsed-field gel electrophoresis patterns. Variant toxinotypes were found in 9 of the 22 serogroups studied, and some toxinotypes were clearly associated with specific serogroups. Toxinotype VIII is characteristic for all strains of serogroup F. Other serogroups in which variant toxinotypes were commonly found are A1, A15, E, and X. Testing of variability in C. difficile toxin genes not only might be useful as a molecular typing system but also could have implications in diagnostics and pathogenesis.

Bacterial Proteins↗
PubMed1997

Clostridium difficile-associated diarrhea in HIV-infected patients: epidemiology and risk factors.

A retrospective analysis of all the cases of Clostridium difficile-associated diarrhea (CDAD) in hospitalized patients infected with HIV was performed over a 52-month period to assess the incidence, epidemiology, and risk factors of CDAD. A case of CDAD was defined as a patient with diarrhea and a positive stool cytotoxin B assay. Sixty-seven cases of CDAD were recorded in HIV-infected patients between January 1991 and April 1995. The annual incidence of CDAD ranged from 1.7 to 6.4 per 100 HIV-infected patients discharged from hospital. The 67 CDAD cases included 48 (72%) first episodes and 19 (28%) relapses. Serogroup C accounted for 69% of strains from initial episodes of CDAD. To identify risk factors for CDAD, 34 HIV-infected patients with a first episode were compared with 66 HIV-infected controls matched for the length of hospital stay. Three independent factors remained significantly associated with CDAD among HIV-infected patients: CD4+ cell counts <50/mm3 (OR = 5.2; 95% CI = 1.4-19.3; p = 0.01), clindamycin use (OR = 5.0; 95% CI = 1.3-18.3; p = 0.02) and penicillin use (OR = 4.6; 95% CI = 1.1-18.8; p = 0.03). C. difficile is a common enteric pathogen responsible for nosocomial diarrhea in HIV-infected patients. Clinicians should keep this pathogen in mind when searching for the cause of diarrhea in these patients, especially those who are severely immunocompromised or have received clindamycin or penicillin.

Adult↗
PubMed1996

In vitro susceptibilities of 180 clinical isolates of Haemophilus influenzae to ampicillin, amoxycillin/clavulanate, cefaclor, cefuroxime, cefotaxime, clarithromycin, and azithromycin.

One hundred eighty consecutive, unduplicate isolates of Haemophilus influenzae from clinical specimens collected from November 1994 through February 1995 in nine general hospitals throughout Belgium were examined for beta-lactamase production using a nitrocefin-based test, and for their in vitro susceptibilities to ampicillin, amoxycillin/clavulanate, cefaclor, cefuroxime, cefotaxime, clarithromycin and azithromycin by means of the NCCLS agar dilution test. The isolates were all from respiratory tract specimens. The prevalence of capsular type b was 1.1%, and the overall rate of beta-lactamase production 16.7%. Rates of beta-lactamase production were higher in isolates from children (22.0%) than in those from adults (15.3%), and in isolates from upper respiratory tract specimens (22.0%) than in those from the lower respiratory tract (15.1%). Beta-lactamase-negative ampicillin resistance amounted to 1.1%. Cefotaxime had the highest activity on a weight basis [MIC (minimal inhibitory concentration) for 50% of the isolates tested (MIC50) < or = 0.06 microgram/ml], followed by ampicillin (MIC50 of 0.25 microgram/ml), amoxycillin/clavulanate and cefuroxime (MIC50 of 0.5 microgram/ml), azithromycin (MIC50 of 2 micrograms/ml), cefaclor (MIC50 of 4 micrograms/ml), and clarithromycin (MIC50 of 8 micrograms/ml). Cefotaxime was also the most active drug in terms of susceptibility rates of the isolates (100.0%), followed by amoxycillin/clavulanate and azithromycin (98.9%), cefuroxime (97.2%), cefaclor (89.4%), clarithromycin (82.8%), and ampicillin (82.2%). In conclusion, amoxycillin/clavulanate and cefuroxime retain an excellent activity against H. influenzae, while cefaclor lost some of its activity. The rate of susceptibility to azithromycin was markedly higher than that to clarithromycin; however, its ability to accumulate intracellularly while concentrations in serum and interstitial fluid remain low, should be considered, as it may represent a major drawback to its use in H. influenzae infections.

Adolescent↗
PubMed1996

Enzyme electrophoresis combined with serogrouping for improved differentiation of Clostridium difficile strains.

We used enzyme electrophoresis to study a set of epidemiologically related and unrelated isolates of Clostridium difficile. The 53 strains belonged to the most frequent serogroups (A1, C, G, H and K). Nine electrophoretic profiles were defined on the basis of five enzymes, and two were characteristic of a single strain. Each serogroup was resolved into two or three different enzyme patterns. By combining the two methods we were able to resolve the strains into 12 types. There was an excellent correlation between enzyme electrophoresis and serogrouping data. This method may be of use in investigating nosocomial transmission.

Bacterial Typing Techniques↗
PubMed1996

Effect of Clostridium difficile toxin A on CD11/CD18 expression in vitro.

Clostridium difficile toxin A is chemotactic for neutrophils and induces their emigration into the colonic mucosae of rodents. We found that toxin A did not upregulate neutrophil beta 2 integrins on isolated human neutrophils. These data support the hypothesis that in C. difficile colitis, these adhesion molecules are upregulated by endogenous mediators.

Bacterial Toxins↗
PubMed1996

Genotyping of outbreak-related and sporadic isolates of Clostridium difficile belonging to serogroup C.

Serogroup C of Clostridium difficile is the serogroup most frequently related to outbreaks. Fifty-six toxigenic serogroup C isolates of C. difficile were genotyped by ribotyping PCR (ribo-PCR), random amplified polymorphic DNA (RAPD) assay, and pulsed-field gel electrophoresis (PFGE). Thirty-five of the 56 isolates were recovered from four unrelated outbreaks (Belgium, 1987, 1992, and 1995; France, 1992 to 1993) 7 derived from a spatiotemporal cluster in Cotonou, Benin (1992), and 14 were sporadic isolates. The serogroup C reference strain, also isolated during an outbreak (Belgium, 1983), was genotyped too. Ribo-PCR, the RAPD assay, and PFGE generated 2, 5, and 11 major genotypes, respectively. Combination of the three methods finally yielded 13 general types, although ribo-PCR did not play any role in enhancing resolution. Three general types were recovered from all the isolates from the five outbreaks and the cluster, with two types being predominant. The 14 sporadic serogroup C isolates were divided into 11 overall genotypes. These results indicate that genotyping methods, and more particularly the combination of the RAPD assay and PFGE, can resolve genetic diversity within toxigenic, serogroup C C. difficile strains. Also, this study suggests that outbreak-related serogroup C strains are limited to a few genetically stable and apparently very widely (internationally and intercontinentally) distributed genotypes.

Bacterial Typing Techniques↗
PubMed1995

Evaluation of pulsed-field gel electrophoresis and rep-PCR for the epidemiological analysis of Ochrobactrum anthropi strains.

Pulsed-field gel electrophoresis and polymerase chain reaction genome fingerprinting based on repetitive chromosomal sequences (rep-PCR) were used for typing 14 strains of Ochrobactrum anthropi. Six strains isolated during an outbreak of bacteraemia in patients who had received a contaminated rabbit anti-thymocyte globulin gave identical patterns by both techniques. Different patterns were found in sporadic and reference strains, except for one clinical isolate received from another hospital that showed the same pattern as the epidemic clone. This patient had also received rabbit anti-thymocyte globulin from the same source at the time of the outbreak. This study illustrates the advantages of genetic typing methods in terms of high typeability and discriminating power, even for rare pathogens. Furthermore, it highlights the need for interhospital communication for effective identification of common sources of outbreaks related to intrinsic drug contamination.

Alcaligenes↗
PubMed1995

Use of pulsed-field gel electrophoresis for investigation of an outbreak of Clostridium difficile infection among geriatric patients.

A six-month outbreak of Clostridium difficile infection among elderly residents of a middle-term-care facility was investigated. Pulsed-field gel electrophoresis was used to genotype 22 outbreak strains and 30 epidemiologically unrelated strains. A prospective case-control study was conducted to identify risk factors for epidemic Clostridium difficile-associated diarrhea. All epidemiologically unrelated Clostridium difficile strains of the same serogroup could be differentiated by their DNA patterns with two restriction enzymes (SmaI and KspI). Among clustered strains, two epidemic serogroups (C and K) were identified. Two different DNA patterns were identified among serogroup C strains and three among serogroup K strains. Multivariate analysis showed that the risk of Clostridium difficile infection increased with antimicrobial chemotherapy (beta-lactam agents and pristinamycin) and the presence of a feeding tube. This study confirms the high discriminative power of restriction fragment length polymorphism analysis by pulsed-field gel electrophoresis to describe Clostridium difficile epidemiology. The typing results confirm that infection was principally exogenous in this outbreak. Furthermore, they indicate the need to improve all measures limiting transmission of infection.

Aged↗
PubMed1995

Gamma globulin administration in relapsing Clostridium difficile-induced pseudomembranous colitis with a defective antibody response to toxin A.

A 53-year-old woman suffered six episodes of Clostridium difficile-pseudomembranous colitis. The serological follow-up demonstrated the absence of a rise in IgG and IgA to toxin A. Human pooled gamma globulin was administered during the fifth relapse and raised IgG levels to toxin A. Normal stools reappeared a week later. The role of the antibodies to toxin A and gamma globulin in C. difficile colitis are discussed.

Bacterial Toxins↗
PubMed1995

Treatment of Clostridium difficile colitis. Summary of a round table held in Brussels on March, 3rd, 1994.

Due to the growing incidence and the severity of infections due to vancomycin resistant enterococci, it is now recommended to treat mild to moderate cases of Clostridium difficile-associated diarrhoea with metronidazole while maintaining the use of oral vancomycin in serious or life-threatening colitis. Clostridium difficile is a common cause of diarrhoea after antibiotic therapy and induces a spectrum of diseases ranging from mild diarrhoea to pseudomembranous colitis (PMC). It is considered to be the first cause of diarrhoea occurring among hospitalized patients (1).

Clostridioides difficile↗
PubMed1994

[Rochalimaea henselae, Afipia felis and cat-scratch disease].

Several years ago, Rochalimaea henselae has emerged as an agent of bacillary angiomatosis, bacillary peliosis and recurrent septicaemia that generally occur in patients infected with human immunodeficiency virus. An aetiologic role in cat scratch disease is also suspected widely on the basis of a serologic survey. Its slow growth and its culture requirement explain that this pathogen, a gram-negative bacterium, could not be isolated until 1990. Moreover, blood and tissue samples request lysis and crushing for recovering by culture. The clinical, histological, microbiological and pathogenic aspects of these infections are described and discussed.

AIDS-Related Opportunistic Infections↗
PubMed1994

A particle counting immunoassay for the direct detection of Clostridium difficile serogroup specific antigen in faecal specimens.

The potential of a particle counting immunoassay (PACIA) for the direct detection of Clostridium difficile serogroup G specific antigen in faecal specimens was evaluated. F(ab')2 fragments from a rabbit anti-serogroup G antiserum were covalently coupled to carboxylated latex beads. This reagent was mixed with acid extracts of faecal specimens and the reaction was assayed with an optical counter which discriminated unagglutinated from agglutinated latex particles. Culture for C. difficile, faecal cytotoxin detection, PACIA and serogrouping of C. difficile isolates were performed on 249 stools. Of the 71 culture-negative specimens, none gave a positive result in the cytotoxin assay or in PACIA. Faecal cytotoxin was detected in 100 of the 178 culture-positive specimens. PACIA was positive for 63 of the 71 faecal specimens that yielded serogroup G C. difficile on culture. PACIA gave negative results for all other culture-positive stools tested with one exception, from which a serogroup A7 C. difficile strain was isolated. PACIA detection of serogroup G antigen in faecal specimens showed a sensitivity of 88.7%, a specificity of 99.7%, a predictive value of a positive culture with a serogroup G strain of 98.4%, and a predictive value for specimens that were culture-negative for a serogroup G strain of 95.6%. The results indicate that PACIA with specific antiserum is a rapid and reliable method for detecting serogroup specific antigens of C. difficile in faecal specimens. Clinical applications of the method are discussed.

Agglutination Tests↗
PubMed1994

Human antibody response to Clostridium difficile toxin A in relation to clinical course of infection.

This study investigated whether differences in fecal and serum antitoxin A antibody levels may account for the duration of Clostridium difficile-associated diarrhea (CDAD) and the occurrence of relapses. By an enzyme linked-immunosorbent assay, we tested 40 patients with CDAD including 25 patients without immunodeficiency and 15 patients receiving antineoplastic drugs. Two hundred eighty serum samples and 80 normal stool samples were investigated as controls. In nonimmunocompromised patients, serum immunoglobulin (IgG) and fecal IgA antitoxin A antibody titers were significantly higher in patients who suffered a single episode (n = 21) than in those with relapsing CDAD (n = 4) whose titers were at control levels. Of these 25 patients, eight suffered from diarrhea which lasted for more than 2 weeks. These patients had significantly lower serum- and feces-specific antibody levels than the others who presented symptoms of shorter duration. In cytostatic-treated patients, antitoxin A antibody levels were similar to controls, but relapses occurred in a single case. These data suggest an association between a defective humoral response to toxin A and a more severe form of C. difficile infection. They also indicate that other host-related factors control the severity of CDAD and remain to be elucidated.

Adolescent↗
PubMed1993

Genomic fingerprinting of Clostridium difficile isolates by using a random amplified polymorphic DNA (RAPD) assay.

This study describes the use of a new and easy method called random amplified polymorphic DNA (RAPD) assay to distinguish strains of C. difficile. We used two single short primers (AP4 and AP5) with arbitrary nucleotide sequences in a polymerase chain reaction to amplify genomic DNA. The profiles observed after electrophoretic separation were able to distinguish 20 reference C. difficile strains previously serotyped by Delmée's method. The fingerprints of 11 epidemiologically unrelated C. difficile strains clearly yielded a DNA polymorphism between all the strains. Latterly, RAPD profiles of 11 C. difficile strains isolated from 2 independent suspected outbreaks showed, in each case, a predominant banding pattern corresponding to an epidemic strain. These results suggest that RAPD assay could be a valuable tool for epidemiological studies.

Base Sequence↗