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M Roussel-Delvallez

Publications and source records attributed to M Roussel-Delvallez.

36 records · Page 2Linked to original sources
PubMed1997

Rothia dentocariosa: two new cases of pneumonia revealing lung cancer.

Pneumonia due to Rothia dentocariosa is extremely rare: only 1 case of pneumonia due to this pathogen has been reported in an immunocompromised patient with acute myelocytic leukemia. In this report, 2 new cases of Rothia dentocariosa pneumonia are described in 2 patients with lung cancer. This opportunistic pulmonary agent, belonging to the oro-pharyngeal flora, is also known to cause endocarditis in patients with underlying cardiac pathology.

Actinomycetales Infections↗
PubMed1996

Choice of a routine method for detecting methicillin-resistance in staphylococci.

Four methods were compared for their abilities to detect methicillin-resistance of Staphylococcus strains using mecA gene PCR analysis in 6 h as the gold standard. 57 Staphylococcus aureus and 100 coagulase negative staphylococci (CNS) were evaluated by the oxacillin disc diffusion method (Kirby-Bauer), the automated API (ATB-plus) system (bioMérieux, La Balme les Grottes, France) in 24 h, the rapid BBL Crystal MRSA ID system (Becton Dickinson, Cockeysville, Md.), the oxillin MICs using the NCCLS agar dilution method in 24 h, and the mecA gene PCR analysis. For S. aureus, the correlation was excellent between the BBL Crystal MRSA ID system and mecA gene PCR analysis (positive predictive value = 100%; negative predictive value = 97%) and oxacillin MIC (positive predictive value = 96%; negative predictive value = 96%). The correlation between BBL Crystal MRSA ID and mecA gene PCR was not reliable for CNS (negative predictive value = 68%). For CNS, the slower routine susceptibility methods to identify intrinsic methicillin-resistance were better: API ATB Staph has a positive predictive value = 94% and a negative predictive value = 82%, and the disc diffusion test has a positive predictive value = 95% and a negative predictive value = 74%. However, BBL Crystal MRSA ID was as reliable as some of the other methods tested for CNS after 6 h incubation when the inoculum was increased: positive predictive value = 94% and a negative predictive value = 77%. These results emphasize that genotypic detection of methicillin-resistance will undoubtedly become important to detect rapidly methicillin-resistance, especially for CNS.

Bacterial Proteins↗
PubMed1996

Reliability of quantitative cultures of protected specimen brush after freezing.

Protected specimen brush (PSB) is considered to be one of the standard methods for diagnosing mechanical ventilator-acquired pneumonia at a threshold value > or = 10(3) cfu/ml. Nevertheless, this procedure requires immediate cultures which are not always possible 24 h per day. We therefore wanted to appreciate the diagnostic value of delayed quantitative cultures after specimen freezing. PSB was performed by fiberoptic bronchoscopy on 43 mechanically ventilated patients with suspicion of nosocomial bronchopneumonia. After PSB procedure, two aliquots of 0.5 ml were prepared. One aliquot was plated immediately on different culture media (Group 1). A second aliquot was frozen at -80 degrees C for 24 h, then plated on the same culture media as Group 1 (Group 2). All samples were incubated for 48 h. The diagnostic value threshold of PSB was 10(3) cfu/ml. A total of 47 samples were performed on 43 patients. In Group 1, cultures from PSB were positive in 26 samples and revealed 41 species yielding > or = 10(3) cfu/ml. In Group 2, PSB cultures were positive in 24 samples and revealed 36 species yielding > or = 10(3) cfu/ml. Despite a mean decrease in bacterial count of 1.00 +/- 1.44 log 10 (p < 0.001), most important for Streptococcus pneumoniae and Escherichia coli (respectively 3.22 +/- 2.21 log10 and 2.41 +/- 0.52 log 10), sensitivity and specificity of quantitative cultures after specimen freezing, compared with immediate cultures, were 88% and 100% respectively. We concluded that specimens from PSB could be frozen at -80 degrees C with good reliability except for S. pneumoniae and E. coli, enabling PSB procedure to be performed around the clock.

Bronchi↗
PubMed1996

In vitro bactericidal effect of a beta-lactam+aminoglycoside combination against multiresistant Pseudomonas aeruginosa and Acinetobacter baumannii.

Pseudomonas aeruginosa and Acinetobacter baumannii are frequently isolated in hospital outbreaks of nosocomial infections. In our hospital, among 1018 strains isolated one year in an intensive care unit, 84 strains (8.3%) of P. aeruginosa and 155 strains (15.2%) of A. baumannii were considered responsible for infections. The major problem related to these bacteria is their multiresistant characteristic which confers great difficulty in treating infections. We carried out a 24 h time-kill study to assess the bactericidal effect of three beta-lactams [imipenem (IPM), ticarcillin+clavulanic acid (TCC), piperacillin+tazobactam (PTB)] in combination with each other and with sulbactam (SUL) and amikacin (AKN) against 8 P. aeruginosa strains and 8 A. baumannii strains. The initial inoculum was 10(6) cfu/ml. Antibiotics were tested at clinically achievable concentrations: TCC (112 mg/l), PTB (100 mg/l), IPM (25 mg/l) and AKN (15 mg/l). The results showed: IMP + TCC + AKN = PTB + SUL + AKN = PTB + TCC + AKN > > IMP + SUL + AKN against P. aeruginosa; and PTB + SUL + AKN = PTB + TCC + AKN > IMP + SUL + AKN or IMP + TCC + AKN against A. baumannii. When infection due to these multiresistant strains was suspected, PTB + AKN combined with either TCC or SUL was bactericidal against both strains. These combinations appeared to be an alternative therapy in the treatment of undocumented nosocomial infections in intensive care units. These in vitro results are being evaluated in patients and seem to give good results for the moment.

Acinetobacter↗
PubMed1995

Bactericidal effect of beta-lactams and amikacin alone or in association against Klebsiella pneumoniae producing extended spectrum beta-lactamase.

Ten extended spectrum beta-lactamases producing strains of Klebsiella pneumoniae characterized by analytical isoelectric focusing and studied for their susceptibility to beta-lactam antibiotics, either alone or in combination with a beta-lactamase inhibitor (clavulanic acid and sulbactam) and in association with amikacin. The extended spectrum beta-lactamases were derived from either TEM (CTX-1 = TEM-3) or SHV (CAZ-4 = SHV-5). Killing curves were studied with antibiotics at clinical by achievable concentrations, at MIC and MIC x 4. At MIC, cefotetan, cefotaxime and ceftazidime lacked bactericidal activity. Imipenem was more rapidly bactericidal than meropenem or co-amoxiclav. At MIC x 4, cefotetan and cefotaxime exhibited bactericidal effect but this was less than for imipenem which gave a reduction of 4 log10 of the inoculum. Cefotaxime plus sulbactam gave no bactericidal effect compared with cefotaxime plus co-amoxiclav. A bactericidal effect with cefotaxime plus sulbactam was seen with the addition of amikacin. At clinical concentrations cefotaxime plus co-amoxiclav +/- amikacin was as efficient as imipenem +/- amikacin with a rapid bactericidal effect (5-6 log10 in 30-60 min). We proposed that cefotaxime+co-amoxiclav might be considered as an alternative to imipenem for the treatment of extended spectrum beta-lactamase associated K. pneumoniae injections.

Amikacin↗
PubMed1995

Should Pseudomonas aeruginosa isolates resistant to one of the fluorinated quinolones be tested for the others? Studies with an experimental model of pneumonia.

A clinical isolate of Pseudomonas aeruginosa resistant to pefloxacin (Pef) but susceptible to ciprofloxacin (Cip) was studied to compare the in vitro and in vivo activities of Pef, ofloxacin (Ofl), and Cip. The time-kill curve method showed no bactericidal activity for Pef and Ofl, but a reduction of 4 log10 CFU/ml was achieved with Cip at 1 h. A model of experimental P. aeruginosa pneumonia was used to evaluate in vivo the relevance of the difference in susceptibility observed in vitro. At 36 h, a 100% cumulative survival rate was observed in Cip-treated rats, which was far higher than the survival rate obtained with Pef (53%) or Ofl (46%) (P < 0.001). At 4 h, no bacteremia was observed in Cip-treated rats, whereas 93% of the Pef-treated rats and 80% of the Ofl-treated rats were bacteremic (P < 0.001). The best pulmonary bacterial clearance was observed with Cip. Interestingly, Pef and Ofl, to which the strain was resistant in vitro, showed a fairly good in vivo activity despite sub-MIC concentrations. Cip was more effective than Pef and Ofl in terms of pulmonary and systemic bactericidal activity and provided the best survival rate in animals. We conclude that differences between the different quinolones in terms of the organism's sensitivity assessed in vitro may be relevant and that it might be useful to reconsider the use of a quinolone to which P. aeruginosa shows resistance if the organism shows sensitivity to no other agent.

Animals↗
PubMed1993

Effectiveness of resins in removing antibiotics from blood cultures.

The present study evaluates the effectiveness of BACTEC NR-26A resin-containing medium in removing eight antibiotics from blood cultures. Peak concentrations achievable clinically were chosen. All antibiotics were prepared in fresh human blood samples. Blood samples were obtained prior to and at 15 min and 2, 24, 48, and 72 h after inoculation. Aztreonam, ceftriaxone, imipenem, teicoplanin, and ticarcillin were partially removed from blood cultures.

Anti-Bacterial Agents↗
PubMed1992

Pharmacokinetic study of piperacillin in newborns relating to gestational and postnatal age.

The pharmacokinetics of piperacillin after a single 75-mg/kg intravenous injection as analyzed in 28 neonates with gestational ages of 29 to 40 weeks (A = 29 to 31 weeks, B = 33 to 35 weeks, C = 38 to 42 weeks) and birth weights of 860 to 3900 g during 35 courses. Serum concentrations of piperacillin were determined by high pressure liquid chromatography. A one compartment open model characterized the disposition of piperacillin. Twenty courses were given between Day 3 and Day 5 of life. The elimination half-life and total body clearance were related to gestational age. Differences were significant between Groups A and B and Group C for half-life (4.3 +/- 1.9 and 3.35 +/- 0.75 vs. 2.47 +/- 0.72 hours) and for clearance (1.68 +/- 0.6 and 1.8 +/- 0.4 vs. 2.46 +/- 0.36 ml/min/kg). Volumes of distribution were similar in the 3 groups, from 516 +/- 108 to 633 +/- 226 ml/kg. Fourteen courses were given from Day 9 to Day 11 of life. The same differences were observed between Groups A and B and Group C. Elimination half-life was significantly reduced with simultaneous increase of the total body clearance. In clinical practice, 75-mg/kg intravenous injections every 12 hours during the first week of life and every 8 hours in the second week provide appropriate concentrations in infants of less than 36 weeks gestational age. In full term newborns the 75-mg dosage is appropriate but the number of injections must be increased to 3/24 h for the first week and 4 times daily thereafter.

Bacterial Infections↗
PubMed1988

Routine evaluation of BACTEC NR-16A and NR-17A media.

The purpose of this study was to determine whether the BACTEC NR-16A and NR-17A media were more effective than the BACTEC NR-6A and NR-7A media in recovering organisms from the blood of patients undergoing antimicrobial therapy. A total of 986 sets of four blood culture bottles were compared, giving 141, 174, 93, and 104 isolates with BACTEC NR-6A, NR-16A, NR-7A, and NR-17A, respectively. BACTEC NR-6A and NR-7A media recovered 234 isolates, whereas BACTEC NR-16A and NR-17A media recovered 278 isolates. The recovery rate of bacteria when aerobic resin media were used was better than that with conventional aerobic media (P less than 0.001). The mean detection times were 51.5 and 69.7 h with NR-16A and NR-6A, respectively (P less than 0.01), whereas they were 68.2 and 71.3 h with NR-17A and NR-7A, respectively (P greater than 0.05). The small number of anaerobes recovered precluded a statistical comparison of relative recovery for that group of organisms.

Aerobiosis↗
PubMed1986

[Piperacillin in the newborn infant. A clinical and pharmacologic study].

The study involved 70 neonates born at 27 to 48 weeks of pregnancy (mean: 34.2 weeks) and weighing between 840 and 4350 g (mean: 1860 g). In every case piperacillin was combined with an aminoglycoside. The infants were treated for materno-foetal infection (14), post-partum infection (19), enterocolitis (18, surgical in 9 cases) and other post-operative infections (19). The antibiotic combination was given prophylactically in 2 cases. Fifty micro-organisms were isolated in 39 patients: 24 from blood (hemoculture), 2 from CSF, 24 from multiple peripheral samples. There were 13 Gram-positive organisms (Streptococcus B, D, A, Listeria spp.) and 37 Gram-negative organisms (E. coli 14, Klebsiella spp. 10, Enterobacter spp. 6). Clinical and bacteriological cure was obtained in 67 patients. Three failures were recorded, with resistance to treatment of Klebsiella pneumoniae and emergence (at hemoculture) of Klebsiella oxytoca under treatment in one patient and of Enterobacter cloacae in another patient. A pharmacokinetic study was performed in 47 neonates. Piperacillin (75 mg/kg per dose) was given twice a day until the 8th day post-partum and three times a day subsequently. The antibiotic was administered either by 30-min infusions or by intravenous or intramuscular injections; 124 serum level measurements were carried out at peak and/or residual level. In 44 infants with normal renal and hepatic function the mean residual level was 23 micrograms/ml (range: 7-100 micrograms/ml) and the mean peak level was 119 micrograms/ml (range: 47-278 micrograms/ml). No local or systemic side-effect was noted, and there was no evidence of toxicity.

Bacterial Infections↗
PubMed1986

Routine evaluation of the nonradiometric BACTEC NR 660 system.

The present study compares the sensitivity, accuracy, and practicability of a nonradiometric blood culture system with those of the standard blood culture system in use in our laboratory. A total of 1,080 sets of four blood cultures bottles were compared, giving 143 positive aerobic-medium associations and 139 positive anaerobic-medium associations. The conventional system recovered 171 isolates, whereas the BACTEC NR 660 system (Johnston Laboratories, Towson, Md.) recovered 155 isolated. There were no significant differences in total isolates with either system (P more than 0.05). The BACTEC NR 660 system recovered a slightly lower number of Serratia marcescens and Streptococcus faecalis but a higher number of Pneumococcus spp. The mean detection times were 55.9 h with the conventional system and 31.6 h with the BACTEC NR 660 system (P less than 0.001). Our results demonstrate that the BACTEC NR 660 system is suitable for routine use.

Bacteria, Aerobic↗
PubMed1983

Automated reading of a microtitre plate: preliminary evaluation in antimicrobial susceptibility tests and Enterobacteriaceae identification.

An automated microELISA Reader was evaluated for its ability to read and interpret microtitre plates. A total of 309 microtitre plates were investigated by automated and visual methods. There was disagreement between the methods in one hundred and twelve (0.6%) wells. However agreements between the two methods for susceptibility tests and Enterobacteriaceae identification were respectively 98.8% and 89.3%.

Anti-Bacterial Agents↗
PubMed1982

A microcomputer system for clinical bacteriology: experience of 12 months' trial.

A data processing system using microcomputers was developed in a hospital bacteriology laboratory processing more than 60 000 specimens yearly. The purchase price of the hardware was frs 200 000 (17 500 pounds) and the software was written by the authors. The system has been running since May 1980 without general breakdown. The present configuration allows the processing of specimens, enquiries, scientific and administrative tasks but multiprogramming and cumulative reports are not possible.

Bacteriology↗
PubMed1982

Quantitative bacteriological analysis of amniotic fluid.

Quantitative bacteriological analysis of amniotic fluid (AF) was performed on 60 fluid samples collected by catheter from 50 selected labor patients regarded as liable to infection. AF cultures were positive in 52 cases. The bacterial colony counts ranged from less than 10(2) colony-forming units (CFU) per milliliter to 10(9) CFU/ml. Pathogenic bacteria in neonates such as group B Streptococcus, Escherichia coli, and Listeria monocytogenes were encountered with numerations equal to or greater than 10(7) CFU/ml in groups with clinical findings. An excellent correlation was noted between bacterial counts in AF and clinical data (p less than 0.00006). The results confirm that the quantitative bacteria analysis of the AF is a useful tool for evaluation of an infection risk for neonates.

Amniotic Fluid↗