Biomedical subjects

Y Costa

Publications and source records attributed to Y Costa.

12 recordsLinked to original sources

PubMed2005

[Surveillance of antimicrobial resistance of bacteria isolated from bloodstream infections: data of the French National Observatory for Epidemiology of Bacterial Resistance to Antibiotics (ONERBA), 1998-2003].

UNLABELLED: The French national observatory for epidemiology of bacterial resistance to antibiotics (ONERBA) includes numerous networks for the surveillance of bacterial resistance to antibiotics. OBJECTIVE: The aim of this study was to update antimicrobial resistance data of bacterial pathogens isolated from blood cultures. METHOD: Data was collected from several surveillance surveys reviewed by the ONERBA scientific committee during 2003. RESULTS: Gram positive cocci and Gram negative bacilli accounted respectively for 45 and 49% of all bacteria isolated from blood cultures (N=19 882). The frequency of MRSA among S. aureus was 35%. The frequencies of resistance to penicillin, amoxicillin and cefotaxime of S. pneumoniae were 10, 2, and 0.2%, respectively. In 2002, 70% of coagulase negative staphylococci were resistant to methicillin. Only 50 and 60% of E. coli isolates were susceptible to aminopenicillin and a combination amoxicillin-clavulanic acid, respectively. Since 2001, the susceptibility of E. coli isolates to ciprofloxacin has been regularly decreasing. Imipenem and ceftazidime were the most active antimicrobial agents against P. aeruginosa with a susceptibility rates below 90%. CONCLUSION: Data provided by the ONERBA should allow to improve the quality of empiric antimicrobial treatments.

Anti-Bacterial Agents↗

PubMed2004

Nosocomial infections and hospital mortality: a multicentre epidemiology study.

The aim of this study was to evaluate the number of deaths associated with nosocomial infections (NI) and the contribution of these NI to death. A multicentre descriptive study was conducted in 16 tertiary-care hospitals (14 222 beds) in Northern France. Medical records of consecutive patients who died at least 48 h after admission were reviewed for cause of death, NI and disease severity, before admission and before NI onset. The contribution of NI to death was assessed by agreement between two physicians according to a three-category scale of probability. Among the 1945 patients who died during the study, 26.6% had an NI. According to the agreed diagnosis, NI contributed to the deaths of 284 (14.6%) patients(certainly for 6.6% and possibly for 8%), thereby ranking NI as the fourth most frequent cause of death. Considering the deaths that had not been anticipated independently of NI two weeks before they occurred, NI definitely contributed to 2.8% of them. Lower respiratory tract, bloodstream and surgical wound infections were responsible for 39, 20 and 14%, respectively,of all NI in these patients. The impact of NI on in-hospital mortality seems to be lower than had previously been estimated in France based on US data from the 1970s and 1980s. To improve healthcare quality, further studies are needed to elucidate the processes that may contribute to fatal severe NI.

Adolescent↗

PubMed2002

[Audit of preoperative antibiotic prophylaxis in a surgical site infections surveillance network].

OBJECTIVE: To evaluate the preoperative antibiotic prophylaxis (PAP) prescriptions in a surgical site infection (SSI) surveillance network. STUDY DESIGN: Auto-evaluative audit in a prospective multicenter cohort included in a surveillance system. PATIENTS AND METHODS: Since 1997, surgical wards in volunteer centers monitored all surgery patients each year during a period of two months. Patients were evaluated for SSI during the 30 days following surgery. Participating centers were asked in 2000 to participate to a PAP practice assessment. For each surgery patient, a questionnaire was completed. The "Guidelines for Antibiotic Prophylaxis Prescription in Surgery" edited in 1999 by the Société française d'anesthésie et de réanimation was used as gold standard. RESULTS: 6109 patients were included in the survey from 34 health care centers and 3881 received PAP. 90% of patients received PAP intravenously and 63% received twice the curative dose. PAP was administered within 90 minutes prior to incision in 70% of cases. 78% of PAP lasted less than 24 hours. PAP indication with regards to the type of surgical procedures was assessed in 4629 patients. PAP guidelines were observed in 1573 (34%) patients: 999 patients in whom PAP was not indicated did not receive PAP and 574 received it in compliance with recommended dose and indications. CONCLUSION: Efforts should be made to improve PAP prescription according to standards guidelines.

Anti-Bacterial Agents↗

PubMed2002

Surveillance of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE) in Northern France: a five-year multicentre incidence study.

In order to measure the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and of Enterobacteriaceae producing extended-spectrum beta-lactamase (ESBLE), and to evaluate the impact of the national guidelines for multidrug-resistant bacteria (MDRB) prevention in hospitals of Northern France, a multicentre study was conducted for three months every year starting in 1996, in volunteer hospital laboratories. All clinical specimens positive for MRSA and ESBLE were prospectively surveyed. During the five-year surveillance period, the overall proportion of MRSA was 38.4% in the 28,534 strains of S. aureus, and that of ESBLE was 11.4% in the 6121 strains of Klebsiella pneumoniae and 47.7% in the 2353 strains of Enterobacter aerogenes. The overall incidence rates of clinical specimens positive for MRSA, ESBL-K. pneumoniae and E. aerogenes were 0.84. 0.05 and 0.12/1000 hospital-days (HD), respectively. In the 23 hospitals that participated in the survey every year, the proportion and incidence of ESBLE decreased. Hence, despite recommendations as for isolation precautions, MRSA remains poorly controlled and requires more effective measures.

Anti-Bacterial Agents↗

PubMed2001

Molecular cloning and characterization of cDNA encoding cardosin B, an aspartic proteinase accumulating extracellularly in the transmitting tissue of Cynara cardunculus L.

Cardosins A and B are related aspartic proteinases from the pistils of Cynara cardunculus L., whose milk-clotting activity has been exploited for the manufacture of cheese. Here we report the cloning of cardosin B cDNA and its organ, tissue and cytological localization. The cDNA-derived amino acid sequence has 73% similarity with that of cardosin A and displays several distinguishing features. Cardosin B mRNA was detected in young inflorescences but not in pistils of fully opened inflorescences, indicating that its expression is developmentally regulated. The proteinase, however, accumulates in the pistil until the later stages of floral development. Immunocytochemistry with a monospecific antibody localized cardosin B to the cell wall and extracellular matrix of the floral transmitting tissue. The location of cardosin B in the pistil is therefore clearly different from that of cardosin A, which was found at protein storage vacuoles of the stigmatic papillae and has been suggested to be involved in RGD-mediated proteolytic mechanisms. In view of these results the possible functions of cardosin B in the transmitting tissue are discussed.

Amino Acid Sequence↗

PubMed1998

A control programme for MRSA (methicillin-resistant Staphylococcus aureus) containment in a paediatric intensive care unit: evaluation and impact on infections caused by other micro-organisms.

Methicillin-resistant Staphylococcus aureus (MRSA) is increasingly reported as a hospital-acquired pathogen in intensive care units (ICUs). The inconsistent application of hygiene measures by healthcare workers accounts largely for the epidemic dissemination of such resistant strains. The efficacy of a control programme to prevent spread of MRSA was assessed in our paediatric ICU (PICU) from April 1992 to December 1995. Patients initially had weekly MRSA cultures taken from samples of anterior nares and perineum, but from January 1994, cultures were also obtained upon admission. Immediately after notification, all MRSA carriers were isolated. Education of hospital staff was an essential component of our programme. Nosocomial infection rates were recorded retrospectively in 1992 and 1993, and prospectively in 1994 and 1995. Incidence rates between 'pre-programme' and 'programme' periods were compared. The rate of MRSA infection decreased from 5.9-0.8/1000 Patient-Days (PD), (P < 10(-7). MRSA carriage also decreased from 34-2% (P < 10(-9) and the ratio of MRSA to all S. aureus fell from 71-11% (P < 10(-4). The decrease in the global incidence of infection from 20.1-13.9/1000 PD (P = 0.002) was due only to the decrease in MRSA infection. However, between 1994 and 1995, there was a significant increase in the number of transplant patients despite a constant patient/nurse ratio. The nosocomial infection rates caused by other micro-organisms decreased among the transplant patients from 64.8-33.2/1000 transplanted PD (P = 0.009) between 1994 and 1995. At the same time, we observed a slight increase of infections in non-transplanted patients, which may have been due to the effect of increased overall workload on those patients who were supposed to have fewer nosocomial risk factors. We conclude that implementation of infection control measures directed towards limiting person-to-person spread was effective in controlling high MRSA infection rates in a PICU, but it is important to allow enough time for staff to carry out hygiene practices thoroughly.

Child↗

PubMed1996

Consecutive isolation of homologous strains of methicillin-resistant and methicillin-susceptible Staphylococcus aureus from a hospitalized child.

A multiply resistant, methicillin-resistant Staphylococcus aureus was repeatedly isolated from the anterior nares of a premature neonate hospitalized in an intensive-care unit and treated with multiple courses of antibiotics. Two months following cessation of antibiotic therapy, a strain of S. aureus with a similar antibiotic resistance profile, but susceptible to methicillin, was isolated from three consecutive nasal swabs. Total DNA of the methicillin-susceptible and -resistant isolates was digested with SmaI and resolved by pulsed-field gel electrophoresis. The SmaI restriction profile of the susceptible isolate was similar to that of the resistant one except for the replacement of a 207-kb fragment by a 147-kb fragment. In Southern hybridization, a mecA-specific probe hybridized to the 207-kb SmaI fragment of the methicillin-resistant strain but not to DNA of the susceptible strain. These results suggest that loss of the mecA gene can occur in vivo when antibiotic selective pressure is removed.

Base Sequence↗

PubMed1996

Use of the coagulase gene typing method for detection of carriers of methicillin-resistant Staphylococcus aureus.

Strains of Staphylococcus aureus can be typed on the basis of the polymorphism of the coagulase gene. DNA fragments generated after amplification by polymerase chain reaction (PCR) of the variable region of this gene and digested with the restriction enzyme HaeIII can be compared by their restriction fragment length polymorphism (RFLP). Seventy-nine of 86 (91.8%) methicillin-resistant S. aureus (MRSA) strains isolated in various hospitals had a characteristic RFLP pattern. This pattern differed from those of 32 methicillin-susceptible S. aureus (MSSA). Only one MSSA shared with MRSA the same RFLP pattern. After modification, we applied this method to the rapid detection of MRSA from 255 nasal swabs from patients hospitalized in intensive care units. When screened by plating on Chapman agar, 55 of these samples contained MRSA, whereas 40/55 yielded the expected restriction profile after amplification by PCR. No DNA was amplified by PCR in 9/55 samples and restriction profiles were uninterpretable in six cases. When compared to culture, the positive and negative predictive values of the PCR test were 100% and 93%, respectively. The specificity was 100% and the sensitivity was 72.7%. Since control of spread of MRSA strains in hospitals is based in part on rapid isolation of carriers, this method which allows detection of epidemic MRSA in nasal swabs within a day could be helpful, though culture would still be necessary to confirm the result.

Bacterial Typing Techniques↗

PubMed1996

Prospective, randomized trial of two antiseptic solutions for prevention of central venous or arterial catheter colonization and infection in intensive care unit patients.

OBJECTIVES: To compare the efficacy of a newly available antiseptic solution (composed of 0.25% chlorhexidine gluconate, 0.025% benzalkonium chloride, and 4% benzyl alcohol), with 10% povidone iodine, on the prevention of central venous or arterial catheter colonization and infection. DESIGN: Prospective, randomized clinical trial. SETTING: Surgical-trauma intensive care unit (ICU) in a university hospital. PATIENTS: All patients admitted to the ICU and requiring the insertion of a central venous and/or an arterial catheter from July 1, 1992 to October 31, 1993. INTERVENTIONS: Patients were randomly assigned to one of two groups according to the antiseptic solution used for insertion and catheter care. The same solution was used for skin disinfection from the time of catheter insertion to the time of removal of each catheter. MEASUREMENTS AND MAIN RESULTS: Catheter distal tips were quantitatively cultured when catheters were no longer necessary, if there was a suspicion of catheter-related infection, and routinely after 7 days of use for arterial catheters, or after 15 days of use for central venous catheters. The rate of significant catheter colonization (i.e., > or = 10(3) colony-forming units [cfu]/mL by quantitative culture), and catheter-related sepsis (as defined by sepsis abating following catheter removal per 1,000 catheter-days), were significantly lower in the chlorhexidine group (12 vs. 31 [relative risk 0.4, 95% confidence interval 0.1 to 0.9, p < .01] and 6 vs. 16 [relative risk 0.4, 95% confidence interval 0.1 to 1, p = 0.5], respectively). The rate of central venous catheter colonization and central venous catheter-related sepsis per 1,000 catheter-days were also significantly lower in the chlorhexidine group (8 vs. 31 [relative risk 0.3, 95% confidence interval 0.1 to 1, p = .03] and 5 vs. 19 [relative risk 0.3, 95% confidence interval 0.1 to 1, p = .02], respectively). Finally, the rate of arterial catheter colonization per 1,000 catheter-days was significantly lower in the chlorhexidine group (15 vs. 32 [relative risk 0.5, 95% confidence interval 0.1 to 1, p = .05]), whereas the rate of arterial catheter-related sepsis per 1,000 catheter-days was similar for the two study groups (8 in the chlorhexidine group vs. 10 in the povidone iodine group [relative risk 0.8, 95% confidence interval 0.1 to 2.2, p = .6]). The 0.25% chlorhexidine solution was superior to the 10% povidone iodine solution in preventing catheter colonizations and catheter-related sepsis due to Gram-positive bacteria (5 vs. 20 [p < .001], and 2 vs. 10 [p < .001], respectively), whereas the activity of the 0.25% chlorhexidine solution was nonsignificantly superior in preventing Gram-negative infections (7 vs. 4 [p = .5], and 4 vs. 2 [p = .8], respectively). CONCLUSIONS: The 4% alcohol-based solution of 0.25% chlorhexidine gluconate and 0.025% benzalkonium chloride was more effective than 10% povidone iodine for insertion site care of short-term central venous and arterial catheters. This effect appeared related to a more efficacious prevention of infections with Gram-positive bacteria.

Adult↗

PubMed1995

Limited usefulness of urinary dipsticks to screen out catheter-associated bacteriuria in ICU patients.

The use of urinary dipsticks to screen out sterile urine specimens was investigated in catheterized ICU patients. During a three-month period, each urine sample quantitatively cultured was concurrently tested at the bedside with a dipstick. A total of 102 urine samples taken from 43 patients were analysed. Thirty-eight of them showed bacterial or yeast growths (incidence rate, 37%). The negative predictive value of the leukocyte esterase pad and/or the nitrate test pad to screen out sterile urine samples was 81%, indicating that dipsticks cannot routinely be proposed to select catheterized ICU patients for quantitative culture of urine.

Bacteria↗

PubMed1993

[Acute pyelonephritis in women. Short-term hospitalization].

One-hundred women suffering from acute pyelonephritis were hospitalized for less than 4 days on average, in order to make a diagnosis based on bacteriology and computerized tomography (CT) and to bring fever down with a 21-day antibiotic therapy. In cases of acute pyelonephritis due to a urinary tract obstacle, endoscopic uereteral drainage was added to the antibiotic treatment. In the absence of obstacle, medical treatment was sufficient to obtain apyrexia. Fluoroquinolone therapy made it possible to reduce the hospital stay to 2 or 3 days, depending on whether the lesions observed at CT were triangular or round.

Acute Disease↗

PubMed1993

Characterization of the chromosomal aac(6')-Ii gene specific for Enterococcus faecium.

Chromosomal gene aac(6')-Ii of Enterococcus faecium CIP 54-32, encoding a 6'-N-aminoglycoside acetyltransferase was characterized. The gene was identified as a coding sequence of 549 bp corresponding to a protein with a calculated mass of 20,666 Da. Analysis of the sequence of the deduced protein suggested that it was the second member of a subfamily of AAC(6')-I enzymes. Insertional inactivation of aac(6')-Ii led to aminoglycoside susceptibility of CIP 54-32, suggesting that this gene plays a role in resistance to AAC(6')-I substrates. The gene was detected by DNA hybridization in all 26 strains of E. faecium tested but not in 44 other enterococci of 13 species. These data suggest that the aac(6')-Ii gene is species specific and may be used to identify E. faecium.

Acetyltransferases↗