[Rhône-Alpes observatory of Streptococcus pneumoniae in 1999: 35 cases of meningitis]. / Observatoire Rhône-Alpes du pneumocoque en 1999: 35 cas de méningites.

In 1999, in Rhône-Alpes region, in a survey of resistance to antibiotics of Streptococcus pneumoniae, 35 cases of meningitis were observed. A retrospectic questionnary was sent to each participant. MICs to Penicillin, Amoxicillin and Cefotaxime were determined with ATB-PNEUMO gallery or E-test and by disk diffusion for the other antibiotics. The results were interpreted according to the recommendations of the CA-SFM. Mean age was 38.1 years (range : 1 month -78 years) and sex-ratio 2/5. Eight patients had previously received antibiotics, 22 patients had risk factors and 23 were transferred in intensive care unit. The patients received C3G + glycopeptide in 15 of 16 children and in 13/19 adults according to the consensus recommendations. Diagnostic was made on the direct examination of CSF in 83%, and blood cultures was positive in 74.3% of cases. The percentage of PRP was 48.6% with 17.1% of intermediate-amoxicilline and 14.3% intermediate-cefotaxime strains. Resistance to trimethoprim-sulfamethoxazole was 45.7%, to chloramphenicol 30% and to fosfomycin 6.9%. All the strains were susceptible to rifampicin and vancomycin. Among the 17 PRP strains, 7 were belonging to serotype 6 (6 in children). The clinical outcome was fatal in 7 male cases (20%), without risk factors in 3 children and 6 of 7 strains were susceptible to penicillin. Six patients (17%) had auditive and/or neurologic sequellaes. This study shows that nearly 50% of strains isolated in meningitis, in Rhône-Alpes region, were not susceptible to penicillin, and confirms the frequency of sequellaes while the mortality is not related with the resistance of strains to the antibiotics.

[Evaluation of the E-test and the ATB-PNEUMo battery for determining the beta-lactam MIC for Streptococcus pneumoniae in daily practice]. / Evaluation du E-test et de la galerie ATB-PNEUMo dans la détermination des CMI aux bêtalactamines de Streptococcus pneumoniae en pratique quotidienne.

In 1999, during the survey of resistance of Streptococcus pneumoniae to antibiotics by 31 clinical laboratories of Rhône-Alpes area, MIC to penicillin (P), amoxicillin (AMX) and cefotaxime (CTX) of 877 PRP strains or with a diameter of inhibition to oxacillin inferior to 26 mm, were determined by each institution by E-test (n = 220 strains) or ATB-PNEUMO (n = 657 strains). MICs of these three antibiotics were determined by dilution in agar medium by the coordinating center. The essential agreement was respectively for ATB-PNEUMO and E-test 89% versus 84% for P (p > 0.05), of 86% vs 79% for AMX (p < 0.01), and of 91% vs 86% for CTX (p = 0.03). When the strains were classified in clinical category, the differences were significant (p < 0.001) for AMX (85% vs 71%) and for CTX (82% vs 75%) but not for P (73% vs 78%). ATB-PNEUMO method was more sensitive than E-test for the detection of strains susceptible to P (90 vs 73%), to AMX (83 vs 78%) and to CTX (80 vs 72%) and for the strains intermediate to AMX (90 vs 78%). On the contrary, E-test is more specific than ATB-PNEUMO for the detection of P-resistant strains (94 vs 86%). Finally, the specificity of both methods is the same for detection of P-S, AMX-R and CTX-I strains.

[Pneumococcus observatory data in the Rhône-Alps region. Results from 1996]. / Observatoire du pneumocoque en région Rhône-Alpes. Résultats de l'année 1996.

Throughout 1996, 22 hospital-based laboratories in the Rhône-Alpes region of France collected pneumococcal strains and used a standardized protocol to record the following data; patient age and sex; type of specimen; and determination of susceptibility to at least the following antibiotics: oxacillin 1 microgram and 5 micrograms, erythromycin (Ery), tetracycline (Tet), chloramphenicol (Chl), rifampin (Rmp), and loracarbef. For penicillin-nonsusceptible strains (PNSSs), which were identified based on results with oxacillin, MICs for penicillin G, amoxicillin (Amx), and cefotaxime (Ctx) were determined using the E Test, at the study site and agar dilution at the coordinating center. Of the 1153 strains, 65.5% were from adults and 31.8% from children; patient age was unknown in 2.7% of cases. PNSPs (MIC > 0.06 mg/l) contributed 32.9% of strains (I: 23.3%; R: 9.6%) and were more common in children (41.1%) than in adults (28.1%). The frequency of PNSSs varied across specimen types: 27.9% in blood cultures (305 strains), 15.6% in cerebrospinal fluid (32), 38.7% in protected bronchopulmonary specimens (31), 31.5% in unprotected bronchopulmonary specimens (434), 50.8% in acute otitis media (118), and 34.4% in other specimens (221). Among PNSSs, nonsusceptibility (I + R) to other antibiotics was variable: Ery, 62.1%; Tet, 41.5%; Chl, 40.4%; Rmp, 1.1%. Corresponding figures for the overall strain population were Ery, 33.3%; Tet, 22.7%; Chl, 22.8%; Rmp, 0.9%. In addition, 56.5% of PNSSs exhibited multiple drug resistance. Resistance to amoxicillin (MIC > 2 mg/l) was demonstrated for only 5 strains. No strains were resistant to loracarbef or cefotaxime. Serotypes of the 379 PNSSs were as follows: 23F, 26.6%; 14 (25.6%); 9V (18.2%), 6 (8.7%), 15 (5%), 19 (4.5%).

[Comparison of the results of the Etest and the method for determining minimum inhibitory concentrations in solid media for penicillin G, amoxicillin, and cefotaxime for S. pneumoniae. A multicenter study]. / Comparaison des résultats du Etest et de la méthode de détermination des concentrations minimales inhibitrices en milieu solide pour la pénicilline G, l'amoxicilline et le céfotaxime chez S. pneumoniae. Une étude multicentrique.

In 1996-1997 a multicentre study was carried out on 450 Streptococcus pneumoniae strains to compare the MICs and susceptibility categories obtained with the Etest (AB Biodisk) used under routine conditions in 22 hospital laboratories in the Rhône-Alpes region, France, with those obtained by the reference technique of agar dilution performed in a single coordinating centre. Each laboratory detected penicillin resistant pneumococci (PRP) by the oxacillin disk method (1 microgram and 5 micrograms) and determined the MICs of penicillin G (PG), amoxycillin (AMX) and cefotaxime (CTX) by the Etest. All the PRP strains were collected in the coordinating centre where MICs were carried out. The strains were classified as susceptible (S), intermediate (I) and resistant (R) according to the CASFM criteria (Comité de l'Antibiogramme de la Société Française de Microbiologie). The concordance results based on susceptibility categories are as follows: PG = 67.6%, AMX = 63.6%, CTX = 71.5%. Minor errors are as follows: PG = 31.2%, AMX = 36%, CTX = 28.5%. Major and very major errors are rare (0% to 0.6%). Agreement within 1 log2 dilution was obtained for about 80% of the strains. The minor errors results from strains clustering near the breakpoints 1 mg/l (PG) and 0.5 mg/l (AMX, CTX), and from practical difficulties in routine use of the Etest. These discrepancies may result in severe therapeutic problems. This study confirms the limits of the Etest. The authors insist on standardization and rigorous use of the Etest under routine conditions.

[Comparison of four methods for the determination of the susceptibility of 47 strains of Pseudomonas aeruginosa to ceftazidime and cefepime: influence of the choice of interpretative criteria]. / Comparaison de quatre méthodes de détermination de la sensibilité de 47 souches de Pseudomonas aeruginosa" à la ceftazidime et au céfépime: influence du choix des normes interpétatives.

47 isolates of Pseudomonas aeruginosa were tested for susceptibility to ceftazidime and cefepime by four methods (agar disc diffusion, E TEST and API-ATB). Concordance between the methods is good, but the percentage of strains susceptible or of intermediate susceptibility depends of the interpretative criteria (French Committee for Antibiogram or National Committee Control for Laboratory Standards). An international agreement could be useful to compare the bacteriological and clinical studies.

[Value of immunofixation for the typing of serum and urine monoclonal proteins]. / Valeur de l'immunofixation pour le typage des protéines monoclonales sériques et urinaires.

Typing of monoclonal proteins can be performed, after screening by cellulose acetate electrophoresis, by immunoelectrophoresis (IEP) or immunofixation (IF). For sera, IF must be preferred to IEP because this methods is more sensitive and more easy to interpretate, particularly for small monoclonal components and biclonal abnormalities. For urine, patterns obtained by IF must be interpretated cautionaly because of the frequent polycondensed aspect of the non monoclonal light chains from tubular renal failures, and must be verified by a polyacrylamide agarose electrophoresis.

[Identification of Salmonella in 4 hours: comparison of 2 technics]. / Identification des Salmonella en quatre heures: comparaison de deux techniques.

Sixty Salmonella reference strains were identified with two ready-to-use rapid systems (API Rapid 20E and Spectrum 001/002). Genus identification was possible with both the two kits; however, some reactions being uneasy to read, distinction between Salmonella typhi or non typhi is not reliable.

[Sero-epidemiologic study of 277 cases of human leptospirosis in the central eastern region of France between 1972 and 1984]. / Etude seroépidémiologique de 277 cas de leptospirose humaine dans le Centre-Est de la France entre 1972 et 1984.

We reported 277 clinical cases of Leptospirosis with a significant serological title (greater than 100) by lyse-agglutination. Sera were sampled from 1972 to 1984 among 9182 subjects living in Central-Eastern departments of France) for immunological diagnosis of leptospirosis. We noted the stability of the average yearly rate in this region, the difficulty in evaluating the incidence of the disease, the clinical predominance of icterus and the good clinical prognosis with specific antibiotherapy.

[Assay of digoxin on dry-reagent strips]. / Dosage de la digoxine sur supports de réactifs secs.

An automated immunoassay for Digoxin in serum using dry-reagent strips (Stratus Dade) was evaluated, and compared with two others immunoassays (TDX Abbott and ACA Du Pont). Precision, sensitivity and specificity were satisfying, as well as correlation study, but discrepancies observed for some sera proved that these techniques still pose serious problems of specificity or of standardisation.

[Epidemiologic evaluation of a sample of 91 rats (Rattus norvegicus) captured in the sewers of Lyon]. / Bilan épidémiologique d'un échantillon de 91 rats (Rattus norvegicus) capturés dans les égouts de Lyon.

91 rats captured in 1982 in the sewers of Lyon (France) have been examined for the presence of some microorganisms implicated in infections transmissible to man, by direct examination, bacteriological culture or detection of specific antibodies. Bacteriological results have shown a high proportion of carriers of Yersinia enterocolitica and frederiksenii (29%), of Pasteurella pneumotropica (29%), of Staphylococcus aureus (53%), and of Campylobacter jejuni (18%), a low proportion of carriers of Salmonella typhimurium (6%) and Leptospira (7%), and an absence of Listeria. Immunological reactions were often positive with Leptospira (21%), sometimes with Salmonella typhimurium, and always negative with Yersinia and Listeria. This work is a contribution to the knowledge of the health status of sewer rats considered to be an important public health risk as transmitters of anthropozoonoses.

[Electrophoresis of urinary proteins on SDS-polyacrylamide gel, without preliminary concentration]. / Electrophorèse des protéines urinaires en gel de polyacrylamide-SDS sans concentration préalable.

We described a rapid and sensitive method for urinary proteins disc-electrophoresis on unconcentrated urine, by using polyacrylamide-SDS gel in discontinuous gradient. Correlation with a conventional polyacrylamide agarose slab electrophoresis on concentrated urine is good, our technique being more sensitive when proteinuria is low. It had proved to be useful for routine detection of renal failures in clinical laboratories.

[Early detection of Pseudomonas aeruginosa in hemoculture media enriched with nitrates]. / Détection précoce de Pseudomonas aeruginosa dans les milieux pour hémoculture enrichis en nitrates.

Addition of a small amount of nitrates in blood culture media enhances growth of Pseudomonas aeruginosa, and permits earliest detection of that bacteria even in anaerobes media.

[Physicochemical changes in hemoculture media related to blood]. / Modifications physicochimiques des milieux d'hémoculture liées à l'apport de sang.

Inoculation of sterile blood into a blood culture medium causes changes of some physicochemical properties, whose maintenance is necessary for growth of fastidious micro-organisms. During incubation of these media at +37 degrees C, red cells utilize glucose for their metabolism, causing acidification and increase of carbon dioxide partial pressure, while oxygen partial pressure tends to decrease during first days of incubation, and increase after. Experimental conditions (choice of medium, volume of blood incubates, ventilation, glucose concentration) notably modify these results. This work underlines the necessity for a greater standardization of media and of technical conditions, in execution of blood cultures.

[Determination of certain physico-chemical parameters in blood culture media]. / Intérêt de la détermination de certains paramètres physico-chimiques des milieux d'hémoculture.

Growth of delicate or exacting microorganisms needs the maintenance, in the culture medium, of precise and stable physicochemical conditions. In order to improve knowledge of these medium, and specially of their aerobic or anaerobic state, we measured pH, partial pressures for oxygen and carbon dioxide and glucose concentration of nine commercial blood culture media, in their natural conditions of use. Comparative study of experimental results, and study of successive fabrication lots of two of these media (brain-heart and Schaedler) reveals a great variability of physicochemical parameters, and specially of pO2 and glucose concentration, although initial composition of the media has theoretically not changed. It would be desirable that such parameters be better controlled, so as to encourage regularity of composition of blood culture media and, perhaps, their clinical efficiency.

[The estimation of fibrinogen by kinetic immunonephalometry]. / Dosage du fibrinogène par immunonéphélométrie cinétique.

A new immunonephelometric micromethod for the estimation of fibrinogen is described. The reaction, linear between 0.30 g/l and 11 g/l requires only 5 microliters of plasma. The precision and sensitivity of the method are satisfactory. Comparisons with the chronometric technique of Clauss and with the Mancini immunodiffusion technique were made.

Laser nephelometry and radial immunodiffusion compared for immunoglobulin quantification in pathological sera.

We evaluated nephelometers from Behring, Hyland, and Beckman for IgG, IgA, and IgM quantitation in sera from patients with monoclonal gammopathies. The intra-batch precision of each instrument for each immunoglobulin class and for different concentrations of the same immunoglobulin was compared to the one obtained with the radial immunodiffusion method. No nephelometer showed a clearly better precision. The correlation with cellulose acetate electrophoresis was good for each of the three nephelometers. The mean value by the radial immunodiffusion method was higher than corresponding determinations by nephelometry.