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A Buu-Hoi

Publications and source records attributed to A Buu-Hoi.

11 recordsLinked to original sources
PubMed1999

[Stenotrophomonas maltophilia endocarditis following mitral valve prosthesis implantation. Report of a case].

The authors report the first case of early postoperative endocarditis after mitral valvuloplasty due to Stenotrophomonas Maltophilia, a Gram negative organism, in a 37 year old man with no special risk factors. Pyrexia and mitral valve vegetations were the main features, and, in the absence of complications or of embolism, the patient was treated initially with triple antibiotherapy (ceftazidime, amikacine, ciprofloxacine). Relapse two weeks after withdrawal of treatment due to two variants of Stenotrophomas Maltophilia, one of which was resistant to ciprofloxacine, and the presence of a large vegetation, required repeat mitral valvuloplasty and a change in antibiotic therapy (ticarcilline with clavulanic acid, trimethoprim sulphamethoxazole, colistine). This time, the outcome was good. The little known Stenotrophomonas Maltophilia infectious endocarditis is a serious complication and, in the absence of standardised management, the authors suggest that, in view of the multi-resistant character of the organism and in the light of this case, surgery should be considered in association with prolonged antibiotic therapy.

Adult↗
PubMed1995

Inducible and constitutive expression of resistance to glycopeptides and vancomycin dependence in glycopeptide-resistant Enterococcus avium.

A clinical isolate of Enterococcus avium, Ea1, which exhibited inducible, low-level resistance to vancomycin and teicoplanin, and two mutants selected from this strain, Ea3 and Ea31, were studied. Ea3 was vancomycin dependent and derived from Ea1, while Ea31 was not vancomycin dependent, was constitutively resistant, and was derived from Ea3. Hybridization studies revealed that vanA was present in Ea1 and suggested that it was located on a high-molecular-weight plasmid. In the absence of induction, Ea1 synthesized only the natural UDP-MurNAc-pentapeptide precursor, and after induction it synthesized an additional precursor identified as UDP-MurNAc-tetrapeptide-D-lactate. The latter was the only precursor found in Ea3 and Ea31, even after precursor accumulation. From these results, we infer that (i) the low level of resistance to glycopeptides in strain Ea1 may be in part due to the residual synthesis of the normal precursor and (ii) the vancomycin dependence of mutant Ea3 could be due to the fact that this strain does not produce any peptidoglycan precursor in the absence of induction.

Adult↗
PubMed1994

Revisited indications for bone marrow examinations in HIV-infected patients.

We reviewed the indications for and the results of bone marrow examination (BME) from HIV-infected patients as an attempt to improve its diagnostic yield. One-hundred-and-eight bone marrow specimens from 90 patients during a 3-year period were examined. A cytological, histological and microbiological study was carried out on the specimens. Forty-three evaluable examinations (40% of total) performed for cytopenia showed normo- or hypercellularity in 33 (77%). Fifty bone marrow specimens were cultured for mycobacteria with a yield of 42% when the indication was persistent fever. Positive cultures yielded Mycobacterium avium complex in 8 out of 12 patients. Twenty-seven patients had both culture and biopsy; granulomas were associated with all the positive (10/10) and with 1 out of 17 negative cultures (chi-square test: p < 0.001). A bone marrow involvement with lymphoma was found in 2 out of 6 patients with previously diagnosed lymphoma, and biopsy revealed a lymphoma in 2 patients. Morphological bone marrow examination should be associated with other techniques in order to appreciate bone marrow production. Bone marrow biopsy is useful for the investigation of persistent fever since granulomas suggestive of disseminated mycobacteria are frequent and allow a treatment to be initiated before microbiological confirmation and antibiotic susceptibility test.

Adolescent↗
PubMed1993

Analysis of pristinamycin-resistant Staphylococcus epidermidis isolates responsible for an outbreak in a Parisian hospital.

In 1990, over a 6-month period, an increase from 1 to 10% in the incidence of pristinamycin resistance among coagulase-negative staphylococci was observed in four intensive care units of a Parisian hospital. Twenty-three such isolates, as well as 25 pristinamycin-susceptible Staphylococcus epidermidis isolates, were collected and typed by analyzing various bacterial constituents. Two structurally related plasmids of 7.3 and 14.3 kb, carrying the gene vga encoding resistance to pristinamycin, were detected in the 23 pristinamycin-resistant coagulase-negative staphylococci which were identified as S. epidermidis. Although related by numerous common characteristics, 20 of these 23 isolates could be divided into two types, A (17 isolates) and B (three isolates). These types were characterized on the basis of their plasmid contents and hybridization patterns obtained when the EcoRI-digested DNA was probed with plasmid pIP1551 containing an internal fragment of the insertion sequence IS256. These findings suggest that the dissemination of type A epidemic strains was, in large part, responsible for the outbreak.

Base Sequence↗
PubMed1992

Antimicrobial resistance in Streptococcus pneumoniae: an epidemiological survey in France, 1970-1990.

The antimicrobial resistance of Streptococcus pneumoniae was surveyed in 1970-1990 at Saint Joseph and Broussais hospitals in Paris (3,279 isolates) and in 1984-1990 at the National Reference Center for Pneumococci (NRCP) in Créteil (8,128 isolates). All isolates were tested for susceptibility and serotyped. At St. Joseph and Broussais hospitals, the rate of resistance to tetracycline increased from 14% in 1970 to 46.5% in 1978 and then decreased to approximately 20% in 1988-1990. Resistance to chloramphenicol appeared in 1972; its frequency remained at less than 10% until 1990. Resistance to macrolides was first detected in 1976, increased to 20% in 1984, and reached 29% in 1990. Among strains submitted to the NRCP, resistance to penicillin (MIC, greater than or equal to 0.1 mg/L) remained infrequent (less than or equal to 1.1%) between 1984 and 1986 but then increased steadily, reaching 12% in 1990. The frequency of high-level resistance to penicillin (MIC, greater than 1 mg/L) among penicillin-resistant pneumococci increased from 13% in 1988 to 48% in 1990. Compared with other serotypes, the penicillin-resistant serotype isolated most frequently (23F, 49.3%) was more often highly resistant to penicillin and was more often multiresistant.

Drug Resistance, Microbial↗
PubMed1990

Prospective multicenter study of vascular-catheter-related complications and risk factors for positive central-catheter cultures in intensive care unit patients.

To determine the incidence rate of complications associated with vascular catheters in intensive care unit patients and to analyze risk factors for a positive vascular culture, we performed a multicenter study of intensive care unit patients at eight French hospitals. During the study period, 865 intravenous catheters were inserted in 566 patients; 362 (41.8%) were peripheral catheters, and 503 (58.2%) were central catheters. Local complications (i.e., infiltration) occurred significantly more often with peripheral than with central catheters (P less than 0.001); in contrast, fever and bacteremia were significantly more often associated with central than with peripheral catheters (P less than 0.01 and P less than 0.05, respectively). The culture of the vascular-catheter tip was positive for 24% of central catheters (32 of 1,000 catheters days) and for 9% of peripheral catheters (21 of 1,000 catheters days). Staphylococcus epidermidis was the most common microorganism isolated from both peripheral and central catheters, followed by Staphylococcus aureus and Pseudomonas aeruginosa. No significant risk factor associated with positive cultures for peripheral catheters was found by univariate analysis. In contrast, the purpose of the cannula (nutrition and monitoring of central venous pressure), the insertion site (jugular), the dressing type (semipermeable transparent dressing), the antiseptic used to prepare the insertion site (povidone iodine), and routine changing of the intravenous administration set were significantly associated with positive cultures of central catheters. Three factors, duration of catheterization, use of a semipermeable transparent dressing, and the jugular insertion site, were found to be independently associated with positive cultures of central catheters by multivariate analysis.

Catheterization↗
PubMed1986

R-factors in gram-positive and gram-negative aerobic bacteria selected by antimicrobial therapy.

Populations of resistant bacteria emerge by the operation of selective pressure on resistant bacteria. The acquisition of resistance by sensitive bacteria is dependent upon the genetic determinant of the resistance, and its ability to move between different bacterial cells and within cells between different replicons. In contrast to chromosomal mediated resistance, plasmids and transposable elements coding for resistance to antibiotics have been the major factors in the spread of resistance and the prevalence of resistant bacteria in humans, farm animals and poultry. Different types of R-factors can be described. Resistance to ampicillin, tetracycline, chloramphenicol, gentamicin, trimethoprim, erythromycin may exemplify epidemiological aspects of resistance genes in Gram-negative and Gram-positive bacteria. The ecological destiny of resistant bacterial populations suggests the role of other factors than antibiotic resistance: characters of a particular host, host-plasmid relationship and properties which may lead to survival and adaptation in a given niche.

Animals↗
PubMed1984

Transposon Tn10-like tetracycline resistance determinants in Haemophilus parainfluenzae.

Tetracycline resistance (Tcr) determinants from three different strains of Haemophilus parainfluenzae expressed 10-fold higher levels of resistance when mated into Escherichia coli. No plasmid was found in any of the E. coli recipients, even in matings in which a plasmid was identified in the donor Haemophilus sp. The Tcr determinant from Haemophilus sp. caused instability of resident plasmids in the recipient E. coli: all plasmids were lost within 30 generations in antibiotic-free media. However, by serial subculture in antibiotics, stable resident plasmids were obtained which carried the Tcr determinant from Haemophilus sp. and were transferable by conjugation and transformation among E. coli strains. All Haemophilus determinants hybridized with a probe for the Tcr determinant on Tn10, which bears inducible Tcr. However, Haemophilus determinants were constitutively resistant to tetracycline in the Haemophilus donors and in the E. coli recipients. This constitutive expression was recessive to wild-type Tn10 in the same cell, indicating that the constitutive phenotype resulted from the absence of an active repressor. Restrictive enzyme analysis of various E. coli plasmid derivatives bearing a Tcr determinant from Haemophilus sp. demonstrated that the inserted DNA was of similar size (8.95 to 9.35 kilobases), close to that of Tn10. Heteroduplex analysis and DNA:DNA hybridization confirmed that the Tcr determinant from Haemophilus sp. had greater than 90% homology with the Tn10 determinant, including the DNA sequence for the repressor.

Crosses, Genetic↗