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M Struelens

Publications and source records attributed to M Struelens.

At least 37 records · Page 2Linked to original sources
PubMed2000

Assessment of intercentre reproducibility and epidemiological concordance of Legionella pneumophila serogroup 1 genotyping by amplified fragment length polymorphism analysis.

The aims of this work were to assess (i) the intercentre reproducibility and epidemiological concordance of amplified fragment length polymorphism analysis for epidemiological typing of Legionella pneumophila serogroup 1, and (ii) the suitability of the method for standardisation and implementation by members of the European Working Group on Legionella Infections. Fifty coded isolates comprising two panels of well-characterised strains, a "reproducibility" panel (n=20) and an "epidemiologically related" panel (n=30), were sent to 13 centres in 12 European countries. Analysis was undertaken in each centre following a previously determined standard protocol. Results were analysed by the participants, using gel analysis software where available, and submitted to the coordinating centre. The coordinating centre reanalysed all results visually and selected data-sets with gel analysis software. Data analysis by participants yielded reproducibility (R) values of 0.20-1.00 and epidemiological concordance (E) values of 0.11-1.00, with 6 to 34 types. Following visual analysis by the coordinating centre, R=0.78-1.00, and E=0.67-1.00, with 10-20 types. Analysis of three data-sets by the coordinating centre using gel analysis software yielded R=1.00 and E=1.00, with 12, 13 or 14 types. This method can be used as a simple, rapid screening tool for epidemiological typing of isolates of Legionella pneumophila serogroup 1. Results demonstrate that the method can be highly reproducible (R=1.00) and epidemiologically concordant (E=1.00), with good discrimination. The electropherograms generated are amenable to computer-aided analysis, but strict adherence to a previously defined laboratory protocol is required. Following designation of representative type strains and patterns, this method will be adopted by the European Working Group on Legionella Infections as the first internationally standardised typing method for use in the investigation of travel-associated Legionella infections.

DNA, Bacterial↗
PubMed2000

National guidelines for the judicious use of glycopeptides in Belgium.

OBJECTIVE: The 'HICPAC guidelines', published in the USA in 1995 stressed the crucial role of restrictive usage of glycopeptides in the strategy to limit the emergence and spread of resistant enterococci. Because controversy still remains in Belgium on the necessity and feasability of restricting glycopeptide usage, the infectious diseases advisory board (IDAB) developed a consensus statement on the judicious use of glycopeptides in Belgium. METHODS: The literature on the indications for glycopeptide treatment was reviewed, categorized and discussed by a working party of the IDAB.Consequently, the IDAB reached consensus on the warranted indications for glycopeptide use in Belgium. RESULTS: The opinion of the IDAB-members is reported in a consensus statement specifying the indications for treatment and for prophylaxis with glycopeptide antimicrobials, as well as the situations where glycopeptides should not be used, taking into account the specific epidemiology of bacterial resistance, the availability of antibiotics and the common prescribing practices in Belgium. CONCLUSIONS: The IDAB concludes that restrictive usage of glycopeptides must also be a priority in Belgium. Guidelines on the judicious use of these antibiotics adapted to the national situations must contribute to this objective.

Anti-Bacterial Agents↗
PubMed1999

Emergence of Enterobacter aerogenes as a major antibiotic-resistant nosocomial pathogen in Belgian hospitals.

OBJECTIVE: To study the epidemiology of Enterobacter aerogenes infections in Belgian hospitals and determine whether recent trends show an increase in incidence of E. aerogenes infections and antimicrobial resistance. METHODS: Data from the bloodstream infection component of the National Surveillance of Hospital Infections (October 1992 to September 1996 data in 45 hospitals) and from a retrospective study on E. aerogenes clinical isolates (1994 and 1995 data in 41 hospitals) were analyzed. RESULTS: E. aerogenes was recovered from clinical specimens with a mean incidence of 4.6 isolates per 10 000 patient-days and caused 0.20 bloodstream infections per 10 000 patient-days during the surveyed periods, respectively. Both rates increased significantly throughout the years. The proportion of E aerogenes within the Enterobacter genus was 35.4% in clinical isolates and 41.2% in bloodstream infections. Both proportions significantly increased over time. Incidence was not statistically different by hospital size but showed major differences between geographic regions. Resistance rates to third-generation cephalosporins and fluoroquinolones increased, and imipenem resistance emerged in several hospitals. CONCLUSIONS: This report provides evidence of an increase in E. aerogenes infections in Belgian hospitals and documents an increase in antimicrobial resistance of E. aerogenes strains. These figures provide a baseline for further surveillance data.

Journal Article↗
PubMed1998

Gastric perforation due to mucormycosis after heart-lung and heart transplantation.

BACKGROUND: Gastrointestinal complications are a well-documented source of morbidity and mortality after heart and lung transplantation. METHODS: We report on two patients who presented with gastric perforation caused by mucormycosis during the first 2 months after heart-lung and heart transplantation. RESULTS: In the first patient, the clinical presentation was insidious and the diagnosis was made at an advanced stage of the disease. Despite surgery and aggressive antifungal treatment, the patient died. In the second patient, the diagnosis was made promptly, but despite antifungal treatment, he presented with gastric perforation within a week. CONCLUSIONS: These cases illustrate that fungal invasive disease may be a cause of early gastrointestinal perforation after solid organ transplantation.

Adult↗
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

Assessment of resolution and intercenter reproducibility of results of genotyping Staphylococcus aureus by pulsed-field gel electrophoresis of SmaI macrorestriction fragments: a multicenter study.

Twenty well-characterized isolates of methicillin-resistant Staphylococcus aureus were used to study the optimal resolution and interlaboratory reproducibility of pulsed-field gel electrophoresis (PFGE) of DNA macrorestriction fragments. Five identical isolates (one PFGE type), 5 isolates that produced related PFGE subtypes, and 10 isolates with unique PFGE patterns were analyzed blindly in 12 different laboratories by in-house protocols. In several laboratories a standardized PFGE protocol with a commercial kit was applied successfully as well. Eight of the centers correctly identified the genetic homogeneity of the identical isolates by both the in-house and standard protocols. Four of 12 laboratories failed to produce interpretable data by the standardized protocol, due to technical problems (primarily plug preparation). With the five related isolates, five of eight participants identified the same subtype interrelationships with both in-house and standard protocols. However, two participants identified multiple strain types in this group or classified some of the isolates as unrelated isolates rather than as subtypes. The remaining laboratory failed to distinguish differences between some of the related isolates by utilizing both the in-house and standardized protocols. There were large differences in the relative genome lengths of the isolates as calculated on the basis of the gel pictures. By visual inspection, the numbers of restriction fragments and overall banding pattern similarity in the three groups of isolates showed interlaboratory concordance, but centralized computer analysis of data from four laboratories yielded percent similarity values of only 85% for the group of identical isolates. The differences between the data sets obtained with in-house and standardized protocols could be the experimental parameters which differed with respect to the brand of equipment used, imaging software, running time (20 to 48 h), and pulsing conditions. In conclusion, it appears that the standardization of PFGE depends on controlling a variety of experimental intricacies, as is the case with other bacterial typing procedures.

Bacterial Typing Techniques↗
PubMed1998

Absence of direct relationship between intraperitoneal cellular influx and resistance to experimental peritonitis.

Intraperitoneal inflammation is an essential defence mechanism against microbial invasion of the abdominal cavity. We have recently demonstrated that a single contact with heat killed E. Coli or Staphylococcus aureus increased the intraabdominal leukocyte influx in rats later challenged by these microorganisms. The aim of the present study was to investigate some of the mechanisms of this phenomenon and to determine its effect on rats survival in an experimental model of peritonitis. The intraabdominal influx of leukocytes following intraperitoneal injection of E. coli, Pseudomonas aeruginosa or Staphylococcus was stimulated by previous intraperitoneal injection of heat killed microbes. The phenomenon was not specific, pretreatment with E. Coli enhanced the intraperitoneal inflammatory reaction against Pseudomonas and vice versa. On the contrary, pretreating the rats with heat killed microorganisms specifically improved their survival after induction of peritonitis with live bacteria, there was no cross-protection. Heat killed staphylococcus aureus which stimulated a subsequent inflammatory reaction against heat killed E. Coli had no effect on the mortality rates of E. Coli peritonitis. In conclusion, there is no direct relationship between resistance to peritonitis and the amount of leukocytes migrating into the abdominal cavity.

Animals↗
PubMed1997

Pyogenic arthritis caused by streptococcus equisimilis (group-C streptococcus) in a patient with AIDS.

A patient with the Acquired ImmunoDeficiency Syndrome (AIDS) treated with a daily low dose of corticosteroids for chronic atopic dermatitis experienced a sudden episode of unilateral knee arthritis. Culture of the purulent synovial liquid yielded a pure culture of Streptococcus Equisimilis. A four week period of intravenous antibiotherapy combined with repeated drainages allowed a complete recovery of articular function.

AIDS-Related Opportunistic Infections↗
PubMed1997

Direct detection and identification of Pseudomonas aeruginosa in clinical samples such as skin biopsy specimens and expectorations by multiplex PCR based on two outer membrane lipoprotein genes, oprI and oprL.

A multiplex PCR test based on the simultaneous amplification of two lipoprotein genes, oprI and oprL, was designed and evaluated for its ability to directly detect fluorescent pseudomonads (amplification of oprI open reading frame, 249 bp) and Pseudomonas aeruginosa (amplification of oprL open reading frame, 504 bp) in clinical material. A collection of reference strains including 20 different species of fluorescent pseudomonads was tested. Positive PCR results for both genes were observed only for P. aeruginosa isolates (n = 150), including strains of clinical and environmental origin, while only one gene, oprI, was amplified from the other fluorescent pseudomonads. All other bacteria tested (n = 15) were negative by the amplification test. The lower detection level for P. aeruginosa was estimated to be 10(2) cells/ml. Preliminary evaluation on testing skin biopsy specimens from patients with burns (n = 14) and sputum samples from cystic fibrosis patients (n = 49) and other patients (n = 19) showed 100% sensitivity and 74% specificity in comparison with culture. This multiplex PCR assay appears promising for the rapid and sensitive detection of P. aeruginosa in clinical specimens. Further evaluation of its specificity in longitudinal clinical studies is warranted.

Bacterial Outer Membrane Proteins↗
PubMed1996

European multicentre evaluation of a commercial system for identification of methicillin-resistant Staphylococcus aureus.

A commercial system for the rapid detection of methicillin-resistant Staphylococcus aureus, the BBL Crystal MRSA test (C-MRSA ID; Becton Dickinson, USA), was evaluated prospectively and compared with a polymerase chain reaction test for the presence of the mecA gene. Ten European centres tested a total of 676 isolates of Staphylococcus aureus from blood cultures. The system correctly identified 661 (97.8%) isolates within 4 h. All but three mecA gene-negative isolates (99.4% specificity) yielded a negative C-MRSA ID reaction, and 158 of 170 mecA gene-positive isolates were accurately detected (92.9% sensitivity). After repeated testing of discrepant results, sensitivity and specificity increased to 99% and 100%, respectively.

Bacteriological Techniques↗
PubMed1996

Inter-centre comparison of pulsed-field gel electrophoresis for the typing of methicillin-resistant Staphylococcus aureus.

The results of pulsed-field gel electrophoresis (PFGE) of chromosomal DNA of the same 12 methicillin-resistant S. aureus (MRSA) strains of diverse geographical origin, performed in three different laboratories were compared; one laboratory used field-inversion gel electrophoresis (FIGE), one used contour clamped homogenous electrophoresis (CHEF) and one used both (all manufactured by BioRad Laboratories Inc., Hercules, CA, USA). No single method produced the maximum number of chromosomal fragments from all isolates. In only four instances were the same number of fragments identified by any two techniques. Although there were similar trends in strain identification the results showed many discrepancies even with a three-band difference rule to discriminate between strains. Plasmids in seven of the isolates produced a fragment, but this did not affect discrimination of the study isolates. There is a great need to standardise methodology and produce a standard set of strains to assist in this process.

Bacterial Typing Techniques↗
PubMed1995

Rapid identification of Mycobacterium xenopi from bacterial colonies or "Bactec" culture by the polymerase chain reaction and a luminescent sandwich hybridization assay.

Oligonucleotide primers were used in the polymerase chain reaction (PCR) to amplify a specific 584-bp DNA fragment, located in the 16S RNA gene of Mycobacterium xenopi. This set of primers, X222 and X224, was able to discriminate between the pathogen and other mycobacterial species as well as non-mycobacterial strains; it detected down to 3 fg of M. xenopi DNA, i.e. about one genome equivalent. These oligonucleotide primers proved suitable for the routine identification of M. xenopi cultures, starting from one single colony on solid medium or from a liquid culture in Middelbrook 12B "Bactec" medium. In addition, a luminescent hybridization assay was designed for use on PCR-amplified DNA. This system, which, for capture, relied on a matrix-bound oligonucleotide (M30) specific for the genus Mycobacterium and, for detection, on a biotinylated xenopi-specific X221 probe, proved fully specific, highly sensitive and rapid for the evaluation of M. xenopi Bactec cultures at low growth index.

DNA, Bacterial↗
PubMed1994

Tuberculosis presenting as acute hepatitis in a renal transplant recipient.

We observed a kidney transplant recipient in whom acute hepatitis was the initial manifestation of tuberculosis, preceding radiological lung involvement by several weeks. The diagnosis was suspected and treatment initiated based on the finding of a granulomatous hepatitis on liver biopsy. Mycobacterial tuberculosis was grown and identified first in liver samples and only later in sputum and bone marrow. This case illustrates the protean manifestations of tuberculosis in immunosuppressed patients.

Acute Disease↗