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R Bismuth

Publications and source records attributed to R Bismuth.

At least 37 records · Page 2Linked to original sources
PubMed1984

[Enterobacter cloacae. In vivo emergence of a variant resistant to new beta-lactams during treatment with lamoxactam-gentamicin].

In a patient recently operated for an abdominal gun wound, and given gentamicin-cephalosporin (cefoxitin for one day, then moxalactam) for 11 days, treatment failed as a result of emergence of a E. cloacae variant resistant to beta-lactams only, i.e. carbenicillin, mezlocillin, cefamandole (CFM), cefoperazone (CPZ), cefotaxim (CTX) and moxalactam ( MOX ). The initial susceptible strains isolated from blood cultures (SH1, SH2) and the resistant ones isolated 11 days later from pancreatic pus (RP) and blood cultures ( RH1 , RH2 ) shared the same chemotype. MICs of CFM, CPZ, CTX, and MOX were much higher (1 000 to 4 000 fold) for RH1 than for SH1. The biochemical mechanism of resistance showed the six following features: loss of antimicrobial activity of CFM, CTX and MOX added to RH1 cultures; much higher (1 500 fold) beta-lactamase activity for RH1 than for SH1 (iodometric and microacidimetric methods); beta-lactamases focusing at the same pl (greater than 8) produced by RH1 , RP and also, but only after induction, SH1 and SH2; cephalosporinase-type beta-lactamase according to the enzymatic activity profile; restoration of RH1 's susceptibility to CFM, CTX and MOX merely by adding cloxacillin; apparently unchanged crypticity for RH1 . The enzymatic mechanism (cephalosporinase hyperproducing variant) seems very likely.

Adult↗
PubMed1983

[Relation between bacterial sensitivity to antibiotics and the consumption of antibiotics. 2 : Study carried out on Staphylococcus aureus at the Pitié-Salpêtrière Hospital from 1975 to 1980].

From 1975 to 1980, computerized data on the sensitivity of 11 342 strains of S. aureus to the main antibiotics were evaluated in relation to drug consumption and hospital activity. Sensitivity to tetracyclines and chloramphenicol increased by 7.3% and 11.4% respectively, but sensitivity to gentamicin decreased by 12%. There was no change in sensitivity to other antibiotics. In vitro response to methicillin was found to have a considerable influence on changes in sensitivity. Sensitivity to tetracyclines increased among methicillin-sensitive strains, while methicillin-resistant strains became more sensitive to chloramphenicol and less sensitive to gentamicin. During the same period, the consumption of chloramphenicol, tetracyclines and aminoglycosides decreased by 84%, 54% and 15% respectively. Hospital activity remained unchanged. The fact that methicillin-resistant strains failed to become more sensitive to the main antibiotics, with the exception of chloramphenicol, might be due to antibiotic pressure in intensive care units where these strains are usually isolated.

Anti-Bacterial Agents↗
PubMed1983

[Cefotaxime, moxalactam and ceftriaxone: comparison of in vitro activity against hospital strains of Enterobacteriaceae belonging to the 4 principal phenotypes of sensitivity to beta-lactams].

MIC of ceftriaxone, moxalactam and cefotaxime is determined for 827 strains of Enterobacteriaceae isolated in the Central Laboratory of the Pitié-Salpêtrière Hospital between december 1981 and september 1982. Results are distributed according to the species involved and the pattern of sensitivity (S) and resistance (R) to ampicillin (A), carbenicilline (Ca) and cephalotin (Ct). Among the strains ASCaSCtS and ARCaRCtS cefotaxime and ceftriaxone have the lowest MICs. Among the most sensitive strains ARCaSCtR and ARCaRCtR cefotaxime, ceftriaxone and moxalactam have the similar MICs, whereas among the less sensitive ones moxalactam has the lowest MICs. The latter might be the cephalosporin of choice for the treatment of serious infection due to the less sensitive Enterobacteriaceae. On the other hand, cefotaxime and ceftriaxone might be the cephalosporins of choice for the treatment of serious infections due to the most sensitive Enterobacteriaceae.

Anti-Bacterial Agents↗
PubMed1983

[In vitro synergy between sulfamethoxazole and trimethoprim on strains of Staphylococcus aureus sensitive and resistant to methicillin].

The synergy between sulfamethoxazole (SMZ) and trimethoprim (TMP) is studied on 91 methicillin sensitive S. aureus strains (methi.S) and 95 methicillin resistant S. aureus strains (methi.R). In methi.S strains, the MIC 90% of SMZ, TMP and SMZ + TMP (19 SMZ/1 TMP) is respectively 64, 0.5 and 2 mg/l. 98% of methi.S strains have a FIC index less than or equal to 0.6 and only one strain has a FIC index greater than or equal to 0.6. In methi.R strains, the MIC 90% of SMZ, TMP and SMZ + TMP is respectively 256, 0.5 and 4 mg/l. 77% of methi.R strains have a FIC index less than or equal to 0.6. The relationship between FIC index and disc diffusion method is studied: bridging inhibition zone between SMZ 200 mcg disc, and TMP 2.5 micrograms disc and difference of the inhibition diameter between SMZ + TMP disc and TMP 1.25 micrograms disc. There is a good correlation only in methi.S strains in the first method and in methi.S and methi.R strains in the second method.

Drug Synergism↗
PubMed1983

[Value of the study of fibrinogen affinity in the identification of Staphylococcus aureus. Results of a multicenter study].

The passive haemagglutination reaction for detecting the Staphylococcus aureus fibrinogen affinity was done in a collaborative study. The test was compared to the major tests used in medical microbiology. The test was as efficient as the protein A or coagulase tests. Its simplicity, rapidity and specificity make it a useful tool for the diagnosis of this species.

Fibrinogen↗
PubMed1983

[Activity of intermittently administered rifampicin and cyclopentyl rifamycin (or DL473) on experimental tuberculosis in the mouse].

The results of recent experiences with experimental tuberculous chemotherapy in the mouse give information on the activity of rifampicin (RMP) administered intermittently and on the activity of Cyclopentyl-Rifampicin (or DL473). The activity of RMP decreases as one spaces the treatment without increasing the dose. These observations are compatible with the known facts concerning the mechanism of action of RMP on RNA polymerase, and are unfavourable as regards the intermittent administration of RMP. Cyclopentyl-Rifampicin, a new derivative of Rifamycine SV, administered once per week, is as active as RMP administered six days per week, both in the initial as well as the continuation phase of treatment.

Animals↗
PubMed1982

[Pharmacokinetic basis for antibiotic therapy in broncho-pulmonary bacterial infections (author's transl)].

Pharmacokinetics is the study of the absorption, distribution and elimination of a drug in the body. Applied to antibiotic therapy it gives information on the concentrations of antibiotic that reach the bacteria at a given time at their site of multiplication for a given dose and route of administration. The future of an antibiotic within a body is largely related to passive transfer. This can be compared to the dialysis of molecules across a semi-permeable membrane, the passage from one side to the other being a function of the concentration of molecules in the "upstream" side, the size of the molecules and their own particular transfer speed. The final result is affected by 1) the partition coefficient itself related to the degree of aqueous and lipid solubility of the molecules, 2) the degree of ionisation of the molecules, non-ionised molecules being the only ones to be transferred, 3) protein binding as only the unbound fraction is biologically active and capable of diffusing across the membranes, 4) by the interplay of the combined phenomena of resorption, distribution and elimination. Penicillins and macrolides are the antibiotics of choice in broncho-pulmonary infections. The tetracyclines and the sulfamethoxazole-trimethoprim combination come second. The combination of a beta-lactam, an aminoglycoside and/or metronidazole are reserved for the most severe infections. The lung is a particularly well vascularised organ, the pulmonary concentrations of the antibiotic may equal the serum levels. But the concentration in the bronchial secretions only reaches 55% of the serum levels for clindamycin, 25 to 30% for aminoglycosides, minocycline and bacampicillin, 20% for cephalosporins and doxycycline and less than 10% for ampicillin and erythromycin. Only oleandomycine, spiramycin and trimethoprim are present in concentrations equal to those in the serum.

Anti-Bacterial Agents↗
PubMed1981

[Relationship between bacterial sensitivity to antimicrobial agents and their consumption (author's transl)].

Computerized data on the sensitivity of 20,006 strains of Gram-negative bacilli to ampicillin, cephalothin, gentamicin, tobramycin, nalidixic acid and co-trimoxazole were collected and evaluated in relation to drug consumption and hospital activity. Despite species-related differences, global sensitivity increased from 1975 to 1978 by 44.8% for cephalotin, 14.4% for ampicillin, 7.1% for gentamicin and 4.8% for tobramycin. There was no change in sensitivity to nalidixic acid and co-trimoxazole. During the same period the consumption of cephalosporins and aminoglycosides decreased by 28% and 21% respectively. Following a decrease between 1975 and 1977, the consumption of ampicillin and of nalidixic acid (and related compounds) went up again to reach in 1978 the same level as in 1975. Co-trimoxazole consumption remained unchanged. Since hospital activity remained the same throughout the period under study, it seems justified to correlate the increase in bacterial sensitivity observed to the decrease in consumption of antimicrobial agents.

Ampicillin↗
PubMed1981

[Comparison of two methods of evaluation of gentamicin in man : bioassay and enzyme immunoassay (author's transl)].

This study compares two methods of gentamicin determination in blood : bioassay and enzyme immunoassay. Results for 145 patients serums showed a correlation coefficient of 0,895 between the two methods. The accuracy and reproducibility were tested on 10 known samples. Each sample was titrated 10 times. Values obtained and real values are near between 0 and 5 mcg/ml and significantly move away between 6 and 10 mcg/ml by the two methods. Advantages and disadvantages are discussed for each method.

Biological Assay↗
PubMedDate not supplied

[Community-acquired cutaneous infections: causal role of some bacteria and sensitivity to antibiotics].

OBJECTIVE: Identify the bacteria responsible for cutaneous infections observed in private practice and test their sensitivity to currently used antibiotics. PATIENTS AND METHODS: The patients were examined by dermatologists. A bacteriological sample was taken and sent to a central laboratory for identification of the germ and antibiograms were performed and the minimal inhibiting concentrations (MIC) determined. RESULTS: Folliculitis, impetigo and furuncles were the three most frequent primary infections. Four hundred and forty-three patients were included and 442 samples were placed in culture. Cultures were positive in 265 cases (a single bacterial strain in 231 cases). Staphylococcus aureus was isolated in 208 cases, streptococci in 11 and enterobacteria in 3; occasionally several germs were present. Eight strains of staphylococci were meti-R (4 p. 100). All the strains were sensitive to pristinamycin and mupirocin and 90 p. 100 were sensitive to fusidic acid. CONCLUSION: The occurrence and diffusion of resistant strains is a daily concern in hospitals. In general practice, although care must be taken, the problem rarely occurs and the antibiotics used remain effective.

Adolescent↗