International dissemination of Escherichia coli strains with discrepant behaviour in phenotypic antimicrobial susceptibility tests.

Preventing the dissemination of antimicrobial resistance depends on appropriate antibiotic stewardship and accurate antimicrobial susceptibility testing (AST). We report the international dissemination of Escherichia coli strains, showing discrepancies between reference methods when phenotypically tested for susceptibility to piperacillin/tazobactam (TZP). We demonstrate that these related strains are predisposed to problematic TZP AST interpretations.

Predictive factors for a successful mobilization of peripheral blood CD34+ cells in multiple myeloma.

We analyzed the prognostic factors for a successful mobilization and peripheral blood stem cell collection in a series of 57 consecutive patients with multiple myeloma (MM); a new scoring system to predict an adequate mobilization in this subset of patients was also constructed. A total of 221 aphereses were performed in 57 patients with MM. The median time from diagnosis to mobilization was 12 months (range 4-120). Only one line of chemotherapy was administered before mobilization to 36 patients and two or more to 21. The median number of alkylating chemotherapy cycles was 6 (2-33). Two patients were mobilized in complete remission, 32 in partial response, and 23 in stable/progressive disease. Significant adverse prognostic factors for collecting 2.5 x 10(6) CD34+cells/kg or more were: a period of at least 12 months from diagnosis, at least six cycles of alkylating agents, and a plasma cell infiltration of 20% or more prior to mobilization. Patients with three risk factors had a probability of only 0.38 (95% CI 0.3-0.9) for adequate mobilization. Ten patients failed to mobilize; a period from diagnosis of 12 months or more and female sex were unfavorable factors. Patients with two risk factors had a probability of 0.50 (95% CI 0.2-0.8) for failing the mobilization procedure. These findings indicate that MM patients must be mobilized early in the course of the disease, with minimal disease burden before severe hematopoietic progenitor cell injury due to cumulative therapy.

Potential impact of the VITEK 2 system and the Advanced Expert System on the clinical laboratory of a university-based hospital.

A study was designed to assess the impact of the VITEK 2 automated system and the Advanced Expert System (AES) on the clinical laboratory of a typical university-based hospital. A total of 259 consecutive, nonduplicate isolates of Enterobacteriaceae members, Pseudomonas aeruginosa, and Staphylococcus aureus were collected and tested by the VITEK 2 system for identification and antimicrobial susceptibility testing, and the results were analyzed by the AES. The results were also analyzed by a human expert and compared to the AES analyses. Among the 259 isolates included in this study, 245 (94.6%) were definitively identified by VITEK 2, requiring little input from laboratory staff. For 194 (74.9%) isolates, no inconsistencies between the identification of the strain and the antimicrobial susceptibility determined by VITEK 2 were detected by the AES. Thus, no input from laboratory staff was required for these strains. The AES suggested one or more corrections to results obtained with 65 strains to remove inconsistencies. The human expert thought that most of these corrections were appropriate and that some resulted from a failure of the VITEK 2 system to detect certain forms of resistance. Antimicrobial phenotypes assigned to the strains by the AES for beta-lactams, aminoglycosides, quinolones, macrolides, tetracyclines, and glycopeptides were similar to those assigned by the human expert for 95.7 to 100% of strains. These results indicate that the VITEK 2 system and AES can provide accurate information in tests for most of the clinical isolates examined and remove the need for human analysis of results for many. Certain problems were identified in the study that should be remediable with further work on the software supporting the AES.

Ability of the VITEK 2 advanced expert system To identify beta-lactam phenotypes in isolates of Enterobacteriaceae and Pseudomonas aeruginosa.

The Advanced Expert System (AES) was used in conjunction with the VITEK 2 automated antimicrobial susceptibility test system to ascertain the beta-lactam phenotypes of 196 isolates of the family Enterobacteriaceae and the species Pseudomonas aeruginosa. These isolates represented a panel of strains that had been collected from laboratories worldwide and whose beta-lactam phenotypes had been characterized by biochemical and molecular techniques. The antimicrobial susceptibility of each isolate was determined with the VITEK 2 instrument, and the results were analyzed with the AES to ascertain the beta-lactam phenotype. The results were then compared to the beta-lactam resistance mechanism determined by biochemical and molecular techniques. Overall, the AES was able to ascertain a beta-lactam phenotype for 183 of the 196 (93.4%) isolates tested. For 111 of these 183 (60.7%) isolates, the correct beta-lactam phenotype was identified definitively in a single choice by the AES, while for an additional 46 isolates (25.1%), the AES identified the correct beta-lactam phenotype provisionally within two or more choices. For the remaining 26 isolates (14.2%), the beta-lactam phenotype identified by the AES was incorrect. However, for a number of these isolates, the error was due to remediable problems. These results suggest that the AES is capable of accurate identification of the beta-lactam phenotypes of gram-negative isolates and that certain modifications can improve its performance even further.

[Patterns of health care delivery and breast cancer in the department of Isère in 1955]. / Filières de soins et cancer du sein dans le département de l'Isère en 1995.

BACKGROUND: Caring for cancer patients is expensive, warranting verification that health care organization works in a satisfactory way. A first step of this evaluation deals with the description of the pathway followed in the health care system by the patient. METHODS: 671 breast cancer cases were diagnosed in Isère in 1995. According to the place where each treatment (surgery, chemotherapy, radiotherapy) was performed, we described pathways for the patient, either entirely private, public or mixed. Characteristics of the patient (age, place of residence), of the disease (extent of disease, way of discovery) and of the physician (general practitioner, specialist) might have influenced the choice of this pathway. We described and tested the distribution of these characteristics within the 3 groups using univariate analysis. Relative risk of being affected to the private pathway compared to the public one was computed, after adjusting for age, type of physician, extent of disease, way of discovery and sanitary area, using a multivariate analysis (logistic regression). RESULTS: In the department of Isère, the private pathway cared for 55% of breast cancers, the public one 23% and the mixed one 19%. There was no preferential recruitment according to age, physician type, presence of metastasis or of the rural or urban residence. In sanitary area number 5, characterized by an important attraction of the patients by the nearby department of Rhône, 41% of the patients were cared for the private pathway, compared to 63% in sanitary area 4, where most patients were treated in the main town of Isère: Grenoble. After early breast cancer detection with mammography instead of breast cancer screening, probability of being cared for in the private pathway was 2-fold higher (OR = 2) than in the public one. CONCLUSION: In Isère department, early breast cancer detection with mammography is in favor of the private pathway. This is not true for physician type, neither for characteristics of the patient or extent of the disease. Finally, the distance to next department of oncology or radiotherapy plays a major role.

Allogeneic or autologous stem cell transplantation following salvage chemotherapy for adults with refractory or relapsed acute lymphoblastic leukemia.

Over a 9-year period 37 consecutive adults with primary refractory (n = 13) or first relapse of ALL (n = 24) received an intensive salvage chemotherapy regimen with the final intention of undergoing stem cell transplantation (SCT). Twenty-nine patients who achieved complete remission (CR) were assigned to receive autologous SCT (autoSCT) or allogeneic SCT (alloSCT) based on age and availability of a histocompatible sibling. Of the 19 patients assigned to autoSCT, 10 did not reach the transplant due to early relapse (n = 9) or fungal infection (n = 1), and nine were transplanted a median of 2.5 months (1-8) from CR, eight with an immunologically purged graft. One patient died early from ARDS and eight relapsed 2-30 months post-SCT. Three of the 10 patients assigned to alloSCT relapsed early, but all 10 received the assigned transplant a median of 2.5 months (1-7) from CR. Four died from transplant-related complications 0.7-12 months post-SCT, and six are alive and disease-free 9.7-92.6 months after the procedure. In an intention-to-treat analysis, the mean overall survival from CR for those assigned to autoSCT and alloSCT are 11.3 months (0.5-34.3) and 60.1 (2.3-98.3), respectively (log-rank, P < 0.01). Only 65% of patients who reached CR and 51% of the initial 37 cases underwent the intended SCT. We conclude that few adults with refractory or relapsed ALL actually reach SCT in CR even when the protocol used is designed for this purpose. AutoSCT appears to offer little benefit in this setting, and an alloSCT from a related or unrelated donor should be rapidly pursued after achieving CR.

[Prevalence assessment of colorectal and breast cancers in the Rhône-Alpes area]. / Estimation de la prévalence des cancers colorectaux et du sein dans la région Rhône-Alpes.

Prevalence of malignant neoplasm is a basic health indicator used in order to evaluate needs in medical equipment for treatment and follow-up of cancer patients. Data on prevalence are regularly published by Northern European countries. Thames and Connecticut cancer registries. In France available information on prevalence are scanty, because follow-up of cancer patients is not easy. Therefore, we used a statistical method to evaluate prevalence from incidence and mortality in the Rhône-Alpes area (France, 5,300,000 inhabitants) in 1990, using the department of Isère population based registry. For females, figures for breast carcinoma and colorectal carcinoma are respectively 25,000 and 5,700, and, for males, 5,700 colorectal carcinoma. For 5 year partial prevalence, these figures are respectively 11,300, 3,100 and 3,500. The ratio prevalence/incidence is 8.9 for breast in females, 5.8 for colorectal carcinoma in females and 4.8 for colorectal carcinoma in males with a steep decrease for 5 year partial prevalence (4 for breast carcinoma, 3.1 for females colorectal carcinoma and 2.9 for males colorectal carcinoma). These ratios are consistent with those observed elsewhere in Europe.

Evaluation of an expert system linked to a rapid antibiotic susceptibility testing system for the detection of beta-lactam resistance phenotypes.

Interpretive reading of antibiotic disc agar diffusion tests indicates the resistance mechanisms, if any, expressed by a bacterium. An expert system for determining resistance mechanisms using rapid automated antibiotic susceptibility tests has been developed. The beta-lactam susceptibility of each of 300 strains of clinically significant species of enterobacteria, displaying natural and acquired resistance mechanisms, was determined by disc agar diffusion and by a rapid automated method of susceptibility testing associated with an expert system. For every strain, the conclusion of the expert analysis of the automated test was compared with the commonly accepted interpretation of disc agar diffusion tests. Of the 300 strains studied, 275 were similarly interpreted (91.7% agreement). The susceptible and naturally beta-lactam-resistant phenotypes (wild phenotypes) were equally recognized by both methods. Similarly, the results of the two methods concurred for most of the acquired resistance phenotypes. However, for 25 strains (8.3%) the results diverged. The expert system proposed an erroneous phenotype (5 strains), several phenotypes including the correct one (17 strains), or no phenotype (1 strain). For 2 strains the natural resistance mechanism was not detected at first by the automated method but was subsequently deduced by the expert analysis according to bacterial identification. These results demonstrate that satisfactory interpretive reading of automated antibiotic susceptibility tests is possible in 4 to 5 hours but requires careful selection of the antibiotics tested as phenotypic markers.

[Use of population based registries in developing a regional medical program against cancer. Example of the Rhone-Alpes region]. / Utilisation des données des registres pour la réalisation d'un Schéma régional d'Organisation Sanitaire en cancérologie. Exemple de la région Rhône-Alpes.

The need for public health planning in France, recently led to the development of a Regional Program in Public Health Organisation (SROS) to describe geographical distribution of facilities and health care activities, in accordance with population needs. Isere Cancer Registry, using its own mortality and morbidity data, evaluated incidence (16,000 new cases each year) and prevalence (100,000 cases) in the Rh-one-Alpes area. Thus, knowing incidence and prevalence of cancer within each district by age and sex, it became much easier for public and private hospitals to quantify their future activities. Today, French cancer registries are conducting methodological studies to improve prevalence estimates, in order to use them in predicting future costs of health care in oncology.

Determination of MICs for staphylococci using the API ATB quinolone and API ATB macrolide systems.

The determination of minimal inhibitory concentrations (MICs) is cumbersome, but remains necessary in certain cases. We tested the two ATB MIC experimental strips (Biomérieux SA), of which each contains 4 antimicrobials of the same class. These strips can be read automatically. The MIC quinolone strip contains nalidixic acid, pefloxacin, ofloxacin and ciprofloxacin, whereas the MIC macrolide (lincosamide-streptogramin) strip contains erythromycin, clindamycin, lincomycin, and pristinamycin. In order to evaluate these strips, 102 S. aureus and 63 coagulase negative staphylococci were used. Correlation coefficients for these MICs (micrograms/ml) and disk diffusion inhibition zone diameters (mm) were nalidixic acid -0.59, pefloxacin -0.95, ofloxacin -0.95, ciprofloxacin -0.91, erythromycin -0.98, clindamycin -0.96, lincomycin -0.96, and pristinamycin -0.64. Using the Biomic system (Giles Scientific USA), the same zone diameters were converted to MICs (micrograms/ml). Rates of agreement (+/- 1 dilution) between ATB MICs and Biomic MICs were nalidixic acid 96 p. cent, ciprofloxacin 98 p. cent, erythromycin 99 p. cent and clindamycin 98 p. cent. Rates of agreement between MICs for the same strains determined using agar dilution and ATB MICs were nalidixic acid 93 p. cent, pefloxacin 100 p. cent, ciprofloxacin 99 p. cent, ofloxacin 94 p. cent and erythromycin 96 p. cent. The ATB MIC strips are an easy-to-use tool for MIC determination and their composition is well-suited to the study of phenotypic resistance and detection of low-level resistance.

[Detection of the phenotypes of resistance of enterobacteriaceae to aminoglycosides with ATB Plus Expert System]. / Détection des phénotypes de résistance des entérobactéries aux aminosides avec le système expert ATB Plus Expert.

ATB Plus Expert (Biomérieux SA) is an expert system which has been developed to perform an interpretative reading of ATB susceptibility tests. The system was tested on the results obtained for 217 strains of enterobacteriaceae. These strains were selected in order to cover a maximum of bacterial species and resistance mechanisms. The isolates were tested on rapid ATB E, rapid ATB G-, rapid ATB Ur, ATB G- and ATB Ur strips. In parallel, a disc diffusion susceptibility test was performed with 5 discs of aminoglycosides (kanamycin, gentamicin, tobramycin, netilmicin, amikacin) and the interpretation was carried out according to the criteria usually followed. Of the 217 strains tested, 122 showed a resistance phenotype. Only the rapid ATB E strips included kanamycin and allowed the detection of APH(3') phenotypes. Amikacin was not included in the ATB Ur strip, consequently it was impossible to discriminate AAC(3)-II and AAC(6') + AAC(3)-I phenotypes. 12 strains did not grow within 5 hours using the rapid ATB methodology. Not taking into account the problems previously encountered, different phenotypes between the 6 susceptibility tests were found for 16 strains. In 5 cases the expert system detected an anomaly instead of the correct phenotype, and in 3 cases of unknown phenotypes, the answers were variable. In the other cases, the main difficulty was the detection of the isolated resistance to gentamicin (AAC(3)-I phenotype). The expert system automatically corrects the susceptibility test result according to the phenotype observed.

[Influence of the culture medium (Isosensitest or Mueller-Hinton) on the results of antibiotics susceptibility testing and its interpretation]. / Influence du milieu de culture (isosensitest ou Mueller-Hinton) sur le résultat de l'antibiogramme et son interprétation.

The individual results of the antibiotic susceptibility tests of 110 Enterobacteriaceae to 31 antibiotics (beta-lactamines, aminoglycosides, quinolones) have been compared on Mueller-Hinton and Isosensitest. No difference between the diameters of inhibition has been shown by the paired t test or signed rank test. The identification of the phenotypes of resistance (resistance patterns) were compared by principal component analysis and by help of an expert system. The patterns are identical in 99 cases and different in 11 cases. Six pattern were erroneous on Mueller-Hinton and 5 on Isosensitest. Globally both media gave a similar comparable answer in these conditions.

[Time-killing curves of Pseudomonas aeruginosa strains exposed to polymyxin B]. / Etude de la courbe de mortalité de souches de Pseudomonas aeruginosa exposées à la polymyxine B.

The time-killing curves of three strains of Pseudomonas aeruginosa (PA01, ATCC10145 and ATCC27853) exposed to five concentrations of polymyxin B comprised: a latency phases, one or two decreasing phases and for the low polymyxin B concentrations a growth phasis. The five antibiotic concentrations were chosen to have a weak bactericidal effect such that decreasing exponential or biexponential models can be fitted to the data. In our experimental conditions, increasing Ca++ and Mg++ concentrations in the medium (Mueller-Hinton) reduced the bactericidal effect and increased the growth phases. Increasing inoculum (10(5) to 10(7) CFU/ml) decreased the bactericidal effect observed with polymyxin B.

[Mathematical study of the sensitivity curves of Escherichia coli exposed to polymyxins]. / Etude mathématique de la courbe de mortalité d'Escherichia coli exposé aux polymyxines.

The time killing curves of five strains of Escherichia coli (ATCC 25922, ATCC 29194, CIP 54125, CIP 54127, CIP 54117 (K 12)) exposed to five concentrations of polymyxin B are similar: latency phasis, two decreasing phasis and for the low polymyxin B concentrations growth phasis. In our experimental conditions, the Mg(+)+ and Ca(+)+ concentrations of the medium (Mueller-Hinton; medium A: Ca(+)+ = 9 mg/l, Mg(+)+ = 0.5 mg/l; medium B: Ca(+)+ = 35 mg/l, Mg(+)+ = 15.5 mg/l; medium C: Ca(+)+ = 60 mg/l, Mg(+)+ = 20 mg/l) have no time effect upon the killing curves. A decreasing biexponential model can be fitted to the data. Such a model is compatible with interaction between antibiotic and bacterium and can be formalized accorrding to the equation: T + ATB K1 in equilibrium of K2 T* - ATB K3----ATB + dead with ATB: Polymyxine B in excess, T: target bacterium and T*: modification target bacterium.

Determination of G + C content of DNA using high-performance liquid chromatography for the identification of staphylococci and micrococci.

The guanine-plus-cytosine (G + C) content of different species of Staphylococcus and Micrococcus was determined by high-performance liquid chromatography. Purified bacterial DNA was hydrolysed by nuclease P1. The nucleotides were separated by chromatography and quantified by measurement of the optical density at 260 nm. The G + C content of staphylococci ranged from 31.5 to 37.9 moles %, and that of micrococci from 68.7 to 75.2. Most of our results were comparable to those obtained with the thermal method.

[Interpretative reading and quality control of an antibiotic sensitivity test using an expert system. Application to the API ATB system and Enterobacteriaceae]. / Lecture interprétative et contrôle de qualité de l'antibiogramme à l'aide d'un système expert. Application à l'automate API ATB et aux entérobactéries.

An expert system (cadi-yac), written in Turbo-Prolog and working on IBM PC and Bacanal + (a management software of microbiology laboratory) was used to recognize and correct the phenotype of antibiotic sensibility. The results were there of API ATB system. The knowledge was adapted from two references works. A routine use of the expert system give a correct recognition of enzymatic profile in more than 80% cases for the beta-lactams and more than 98% cases for the aminosides. The mistakes detected by cadi-yac, were often interpreted as deficiency of API system by humans experts. The expert system mistakes (1.5%) were due composites phenotypes.

[Demonstration of an inoculum effect on the estimation of the minimal inhibitory concentration of LY 146032]. / Mise en évidence d'un effet inoculum sur l'estimation de la concentration minimale inhibitrice du LY 146032.

This work has been performed to study the inoculum effect on the in vitro activity of LY 146032, a new lipopeptide antibiotic. A statistical analysis (X2 and t test) of the data concerning the MIC of different bacterial groups has been carried out to appreciate the phenomenon. The activity of vancomycin has been compared. A major inoculum effect has been detected for LY 146032. It must be taken into account to evaluate the activity of this new antibiotic.

[Bullous muco-synechial dermatitis atrophicans. Development and current nosological status]. / Dermatitis ampollar mucosinequiante y atrofiante. Evolución y ubicación nosológica actual.

The authors report six cases of cicatricial pemphigoid emphasizing the initial sintoms and signs of the disease and its ocular localization in order to make an early diagnosis and an efficient therapeutic control; so as to avoid the cicatricial complications. From the therapeutical point of view me propose the use of local therapy and permanent contact lenses.

Dermatitis ampollar mucosinequiante y atrofiante. Evolucion y ubicacion nosologica actual. / Cicatricial pemphigoid. Course and current nosological localization

El motivo de nuestra comunicacion es destacar los primeros sintomas y signos de esta afeccion, con localizacion exclusiva ocular. Todo ello no solo nos facilitaria el diagnostico precoz y el control terapeutico eficaz sino que ademas demoraria o evitaria la formacion de bridas y otras complicaciones. El tratamiento inespecifico local y la protesis ocular por lentes de contacto permanentes cumplirian en parte nuestro proposito