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B Mirelis

Publications and source records attributed to B Mirelis.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Detection of resistance to the amoxicillin-clavulamic acid combination in Salmonella and Shigella].

PURPOSE: To study the emergence of amoxicilline/clavulanate resistance in Salmonella and Shigella. MATERIAL AND METHODS: We have studied 118 strains of Salmonella enterica and 11 strains of Shigella flexneri isolated in our laboratory along 1993. The MICs values for amoxicilline/clavulanate were determined by the E-Test method and confirmed by the standard agar dilution method. RESULTS: We have observed that 6% (7 out of 118 strains) of Salmonella enterica and 42% (5 out of 11 strains) of Shigella flexneri isolates exhibited an intermediate susceptibility or were resistant to amoxicilline/clavulanate with MICs values ranging between 16 mg/l and 32 mg/l. CONCLUSIONS: Along 1993 we have detected the emergence of an amoxicilline/clavulanate resistance in salmonellae and shigellae strains. To our knowledge this fact has not been published up to now (Medline, 1990-October 1994). We don't know the clinical importance of this fact.

Amoxicillin↗
PubMed1996

Evaluation of an enzyme immunoassay for verotoxin detection in Escherichia coli.

Verotoxin-producing Escherichia coli strains (VTEC) cause hemorrhagic colitis and hemolytic-uremic syndrome in humans. Laboratory diagnosis by conventional methods is slow and cumbersome. The results of a new rapid enzyme immunoassay (EIA Premier EHEC) for verotoxin detection both in isolated strains and in clinical samples are presented, and they are compared with cell culture (CC) and polymerase chain reaction (PCR) techniques. Fifty-four strains have been analyzed by both EIA and PCR, and 33 by all three methods. The kit has also been evaluated for experimentally infected stool samples directly and after their enrichment on MacConkey broth. Nineteen, out of the 54 strains, were positive by EIA and 20 by PCR. The results of the 33 strains evaluated by the three techniques were coincident with one exception. The latter was uninterpretable by CC, negative by EIA and positive by PCR. The sensitivity of the kit for experimentally infected stool samples was approximately 5 x 10(7) bacteria/ml in the direct test, and 5 x 10(4) bacteria/ml after broth enrichment. EIA sensitivity and specificity were similar to those of CC and PCR. The diagnostic times were 18h for EIA, 3 days for PCR and 5 days for CC. Sensitivity, rapidity and ease of performance make this technique especially valuable for clinical diagnosis.

Animals↗
PubMed1995

[Resistance to imipenem in Enterobacter aerogenes].

BACKGROUND: In June, 1993, an Enterobacter aerogenes strain was isolated in the Hospital de la Creu Roja from Hospitalet de Llobregat (Barcelona), which was resistant against all beta-lactams, including imipenem. Since is unusual in Enterobacter sp. to isolate imipenem resistant strains, we decided to study its resistance mechanism. METHODS: To study the E. aerogenes 174004/H resistance mechanism beta-lactamase isoelectrofocalization was performed together with the determination of kinetic constants in order to characterize the beta-lactamase, and a polyacrylamide gel electrophoresis in order to observe the profile. RESULTS: The strain of E. aerogenes 174004/H exhibits a chromosomic beta-lactamase with a pI higher than 9.2 and a decrease in an outer membrane protein of 42 kDa, probably a porine. CONCLUSIONS: E. aerogenes 174004/H resistance against imipenem is due to an hyperproduction of a chromosomic beta-lactamase with a pI higher than 9.2 and to a 42 kDa decrease of an outer membrane protein expression.

Bacterial Outer Membrane Proteins↗
PubMed1995

[Comparison of the automatized BacT/ALERT blood culture incubation and reading system and a conventional system].

BACKGROUND: The aim of the present study was to compare the BacT/ALERT blood culture automatic management and reading system (Organon Teknika) with a conventional, nonautomatic technique (DUO, Bio-Mérieux). METHODS: 1,405 blood cultures were parallel compared. 263 of them were positive; out of these, 148 were considered as indicative of septicaemia, 38 of doubtful clinical significance and 77 as accidental contaminations. RESULTS: No differences were detected between both systems neither in the number of isolates obtained nor in the kind of microorganisms recovered or in the number of false-positive or false-negative readings. The conventional system detected 28% of significant isolates during the first 24 hours, reaching 77% after 48 hours; whereas the BacT/ALERT system had detected 57% of significant isolates after 12 hours, reaching 82% after 24 hours (p < 0.001). CONCLUSIONS: The results obtained and the automatization of the BacT/ALERT system appoint it as a firm candidate to be included into the Clinical Microbiology laboratory routine.

Adult↗
PubMed1995

In vitro activity of E-4868, a new fluoroquinolone with a 7-azetidin ring, compared with ciprofloxacin, ofloxacin and fleroxacin.

E-4868, (-)-7[3-(R)-amino-2-(S)-methyl-1-azetidinyl]-1-(2,4- difluorophenyl)-1,4-dihydro-6-fluoro-4-oxo-3-quinolinecarboxylic acid, is a new fluoroquinolone with a 7-azetidin ring substituent. The in vitro activity against clinical isolates was compared with that of ciprofloxacin, ofloxacin and fleroxacin. In general, activity of E-4868 against aerobic and facultative anaerobic Gram-negative bacilli was equal to or slightly less active than ciprofloxacin with the exception of Morganella morganii and Proteus spp., E-4868 MIC90, 1 and 0.5 microgram/ml, respectively. E-4868 activity was two- to eight-fold higher than ciprofloxacin against Gram-positive cocci. For anaerobic species, E-4868 activity was comparable to that of ciprofloxacin, although against the Bacteroides fragilis group E-4868 was four-fold more active than ciprofloxacin.

Anti-Infective Agents↗
PubMed1994

Nosocomial bacteremia in a medical-surgical intensive care unit: epidemiologic characteristics and factors influencing mortality in 111 episodes.

OBJECTIVE: To analyze the epidemiology and factors influencing mortality of ICU-acquired bacteremia. DESIGN: Prospective clinical study. SETTING: A medical-surgical ICU in an university hospital. PATIENTS: We recorded variables from 111 consecutive ICU-acquired episodes for a 3-year period. RESULTS: The attack rate was 1.9 episodes per 100 patient-days. The commonest isolates were coagulase-negative staphylococci, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Intravascular catheters were the most frequent source of infection. Overall mortality was 31.5%, and 65.7% of all deaths were directly attributable to infection. Bacteremia from intra-abdominal, lower respiratory tract or unknown origin were associated with a poor prognosis. A logistic regression analysis defined intraabdominal origin (p = 0.01, OR = 15.7) and presence of shock (p = 0.04, OR = 3.3) as independently influencing the risk of death. No significant differences were found for the remaining variables studied. CONCLUSIONS: Epidemiology and etiology of ICU-acquired bacteremia does not differ seriously in respect to nosocomial bacteremia among unselected populations, although it is associated with a greater incidence and overall mortality. Presence of shock is the most important modificable variable affecting the outcome.

Bacteremia↗
PubMed1993

Polymicrobial bacteremia in critically ill patients.

OBJECTIVE: To characterize the epidemiology of polymicrobial bacteremia (PMB) among critically ill patients. DESIGN: Prospective clinical study. SETTING: University medical center. PATIENTS: All patients with positive blood cultures in a medical-surgical ICU. MEASUREMENTS: PMB represents 8.4% of all true bacteremia in our ICU. Most of these patients were postoperative but none had malignancies or significant immunodepression. Over three-quarters of the episodes were nosocomial. No significant differences in factors associated with PMB were found when they were compared with a cohort of 154 monomicrobial episodes. Enterobacteriaceae were the most common organisms. Intravascular devices (42.8%) were the most common source of PMB, followed by intra-abdominal origin (21.4%). The overall mortality was 7.1%, a lower rate than has previously been described. CONCLUSIONS: We suggest catheter replacement in patients who develop PMB and improving techniques of catheter maintenance in order to reduce its incidence.

Adult↗
PubMed1993

Increased resistance to quinolone in Catalonia, Spain.

From 1989 to 1991, the level of resistance to ciprofloxacin in our hospital increased from 0.47% to 6.7% in opportunistic Enterobacteriaceae, from 9.9% to 16% in Pseudomonas aeruginosa and from 8.27% to 31.8% in Campylobacter jejuni-coli. We also observed an increase in quinolone consumption from 1.1 in 1989 to 1.5 defined daily doses per 1000 inhabitants per day in 1991.

Anti-Infective Agents↗
PubMed1992

[Evaluation of two commercial kits for detection of Helicobacter pylori specific antibodies in patients undergoing gastroscopy. A seroprevalence study in an asymptomatic population].

BACKGROUND: We evaluate two different commercially available kits for detecting specific antibodies against Helicobacter pylori in a group of 48 patients with gastrointestinal symptoms that underwent an endoscopic procedure. We also study the seroprevalence of anti-H. pylori antibodies in asimptomatic individuals from our area. METHODS: Microbiologic and pathologic studies were performed in 48 gastric biopsies, in relation with antibodies detection using ELISA (Pylori stat test, Whittaker) and latex particles agglutination (Pyloriset, Orion). We also used ELISA tests for determining the seroprevalence of H. pylori antibodies in 139 asimptomatic individuals. RESULTS: Ninety-four percent of patients with peptic ulcer disease and 81% of patients without peptic ulcer disease but complaining of dyspepsia were infected by H. pylori. None of the patients with normal gastric mucosae was found to be infected. Sensitivity and specificity of ELISA test were 100% and 73%. Latex test sensitivity and specificity were 46% and 82%. The seroprevalence of antibodies among healthy individuals in our area increases with age (19% among children under 9 years of age) and reaches a peak at 40-49 years of age (84%), with a mean value of 60% in all ages' groups. CONCLUSIONS: There is a high correlation between Helicobacter pylori infection and gastric mucosa alterations. The ELISA test is best correlated with other laboratory data used for defining infection. The seroprevalence of H. pylori antibodies is also high, and therefore we recommend that the use of serologic diagnostic test must be highly selective.

Adolescent↗