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The agent of bovine tuberculosis, Mycobacterium bovis, is a zoonosis which can be transmitted to human beings. In France, the prevalence of tuberculosis due to M. bovis has drastically decreased, both for animals and humans, since public health measures were introduced to prevent its transmission. However, a new outbreak of the disease is noted among cattle in several French areas and more particularly in Aquitaine. In 2008, 40% of bovine tuberculosis French cases provided from Aquitaine. From November 2004 to October 2008, 15 cases were registered at Bordeaux's academic hospital (CHU). Thirteen of them were due to M. bovis and two to Mycobacterium caprae. It represents 2.9% of tuberculosis due to tuberculosis complex. An analysis of the 15 patients' medical files showed that it occurred either to old people who reactivated a former infection, or to younger ones who were born in countries with a strong M. bovis endemic disease. Extrapulmonary forms and especially ganglionics ones are the most frequent. M. caprae seems to be an emergent species among animal mycobacteries transmissible to human being. An epidemiological monitoring seems to be necessary to establish a relation between the regional outbreak of bovine tuberculosis and human tuberculosis., (Copyright © 2011 Elsevier Masson SAS. All rights reserved.)

Unlabelled: Extrapulmonary tuberculosis is usually more difficult to diagnose than pulmonary tuberculosis. It often involves inaccessible sites and it is paucibacillary., Objective and Method: In this study, we tried to analyze the performance of various bacteriological methods used to diagnose 51 cases of extrapulmonary tuberculosis in an infectious diseases ward., Results and Comments: The culture was positive for 55% of patients. The new amplification methods used were very disappointing for the testing of nonrespiratory samples. The sensitivity of PCR was 32% compared to that of diagnostic culture which remains the most sensitive reference method. Liquid media allow for rapid growth and limit the contaminations. The combined inoculation of liquid and solid medium increases the sensitivity and helps to identify the pathogen.

Objective: To describe the incidence of pneumococcal bacteremia not associated with infection of the central nervous system, investigate the susceptibility of bacterial isolates to beta-lactams, evaluate risk factors for antibiotic resistance, and determine factors predicting patient outcome., Methods: Over a period of 1 year, 919 Streptococcus pneumoniae isolates were collected from 919 patients with bacteremia in eight French counties. Their clinical and microbiological features were recorded. Univariate and multivariate analyses were used to determine risk factors for penicillin-non-susceptible pneumococcal bacteremia and predictors of fatal outcome., Results: Of the 919 patients in the study, 27% were infected with penicillin-non-susceptible pneumococci (PNSP): 17.8% of the isolates were intermediate to penicillin, 7.2% were resistant to penicillin, 16% were intermediate to amoxicillin, and 11% were intermediate to cefotaxime; no PNSP were resistant to either of the last two antibiotics. The most common PNSP serotypes isolated were 14 (41%) and 23 (24%). A statistically significant relationship between PNSP infection and age below 5 years or above 60 years in the different counties was observed by univariate and multivariate analysis. Gender, origin of bacteremia, co-morbidity, immunodeficiency, previous hospitalization and nosocomial infection were not predisposing factors associated with PNSP. The mortality rate was 20.6%: there was no increase in mortality among patients with PNSP bacteremia. Age was the strongest risk factor for mortality, but immunodeficiency also seemed to have had an impact on mortality. Clinical outcome was more closely related to clinical conditions than to the susceptibility status of S. pneumoniae., Conclusion: Among cases of bacteremia, 27% were caused by PNSP, but this level varies according to the counties and the age of the patients. Infection-related mortality was high, but there was no increase related to penicillin G non-susceptibility of the infecting strain.

The activity of the pristinamycin was investigated using disk diffusion agar or ATB PNEUMO system and MIC determination using reference liquid medium method (NCCLS) on 749 S. pneumoniae strains isolated in Aquitaine in 1999. We have realized the killing curves against 10 isolates selected from erythromycin-susceptible and resistant S. pneumoniae strains. All the strains tested by ATB PNEUMO system were susceptible to pristinamycin, using disk diffusion agar, 6.8% of strains were intermediate or resistant. However the MIC's of pristinamycin determined by liquid dilution method against these strains were < 1 mg/L. These data suggest that the zone of inhibition around the disk was not correlated with MIC for erythromycin pneumococci and MIC testing must be performed. The results of killing curves showed a very good and rapid bactericidal activity of pristinamycin within two hours for concentration equal to 4 x MIC and four hours for 2 x MIC.

Stenotrophomonas maltophilia is an important nosocomial pathogen. The increased isolates of S. maltophilia among hematology unit patients led to an epidemiological survey. Over 26 months, 24 strains isolated from 23 patients and an environmental isolate from blood pressure armband have been identified. The isolated were first analysed by the use of phenotypical markers: biotype, antibiotic susceptibility, but the minor differences observed justified a genotypic analysis. Pulsed field gel electrophoresis of genomic DNA was carried with XbaI and DraI restriction endonucleases by contour-clamped homogeneous electric field method (CHEF). The data obtained showed a great genomic diversity within the species S. maltophilia. Nevertheless, the same restriction profile was found for 3 patients and 3 other profiles were obtained for 3 couples of patients hospitalized at the same time. All the other strains isolated from subjects hospitalized during the same period exhibited pulsotypes independent from each other. Compared to biotypes and antibiotic susceptibility, these results indicate field only with non modified primers, and the absence of 460 mutations was confirmed by sequencing. Two isolates P1 and P2, from a transplanted patient were amplified with both primers MCMM and MCMW: sequencing analysis shown the presence of a mixture of strains, one of them harbouring A- > G 1378 mutation. One resistant strain was amplified neither with MCMM nor with MCMW: a C- > T silent mutation at nt 1368 was present. As sequencing analysis confirmed PCR results, discriminative PCR enables isolates to be rapidly assessed for the presence or absence of 460 mutations. Moreover, it can distinguish Met to Val from Met to Ile mutations, and allows the analysis of mixtures of sensitive and resistant strains.

The in vitro activity of two new beta-lactam agents, cefpirome (CPO) and cefepime (FEP), was investigated against 295 Gram-negative bacilli (250 enterobacteriaceae and 45 P. aeruginosa) isolated from neutropenic patients. They were compared with ceftazidime (CAZ), piperacillin-tazobactam (TZP), imipenem (IPM) and cefotaxime (CTX). All enterobacteriacae were susceptible to IPM, 16 strains were intermediately susceptible or resistant to CAZ (1 strain of E. coli, 4 of Morganella morganii and 11 of Enterobacter. The 250 strains of enterobacteriacea were susceptible to FEP (MIC < 1 mg/l) and only one strain among them was intermediately susceptible to CPO. Among 45 strains of P. aeruginosa, 21 strains were susceptible to CPO, 30 to FEP, 31 to TZP, 32 to CAZ and 34 to IPM. All the strains were inhibited by less than 32 mg/l of FEP and IPM.

The improvement of survival of AIDS patients allowed the emergence of disseminated Mycobacterium avium Complex infections (D.MAC). Here we report the experience of the group of "Epidémiologie clinique du sida en Aquitaine (GECSA)" about 100 patients. There were no differences according to sex, age and route of acquisition of HIV. Clinical and biological characteristics of the infections were not specific. The mean TCD4+ lymphocytes count was 18/mm3. The diagnostic was generally established by systematic blood culture on Septi-Chek in patients with TCD4+ lymphocytes count below 75/mm3. The recommendations on therapy for D.MAC are to use regimen containing azithromycin or clarithromycin, ethambutol and one of the following drugs, rifabutin, clofazimine, amikacin, or ciprofloxacin. Rifabutin is recommended for prophylaxis in patients with lymphocytes TCD4+ count below 100/mm3.

In an attempt to further characterize infections due to Xanthomonas maltophilia, we reviewed 20 colonisations and 30 infections observed in our institution from january 1990 to december 1992, Xanthomonas maltophilia is emerging as an important nosocomial pathogen in immunocompromised patients, especially those receiving broad spectrum antimicrobial antibiotherapy. Distinction between colonisation and infection is often difficult. Xanthomonas maltophilia presents a therapeutic challenge because of its tendency to exhibit multiple resistance.

In an attempt to further characterize infections due to Xanthomonas maltophilia (XM), we reviewed 50 case reports observed in our institution. XM is emerging as an important nosocomial pathogen in immunocompromised patients, especially those receiving broad spectrum antimicrobial antibiotherapy. Distinction between colonisation and infection is often difficult. XM presents a therapeutic challenge because of its tendency to exhibit multiple resistance.

Infections due to atypical mycobacteria have increased during the past 30 years. Species of Mycobacterium avium, Mycobacterium intracellulare and Mycobacterium scrofulaceum are among the most common non-tuberculous mycobacteria isolated from patients with AIDS or immunosuppressed. These three organisms are taxonomically closely related and identification, according to cultural characteristics and biochemical tests, is not always evident, so some of these related strains are grouped in a "MAIS" complex. Analysis of cellular constituents is an aid to identification. Gas chromatography was used to study mycolic acids and a secondary alcohol was found which is a discriminating constituent between M. scrofulaceum and the other two species. The lipidic analysis was not able to separate M. avium and M. intracellulare, so cell proteins were considered. Sodium dodecyl sulphate polyacrylamide gel electrophoresis of proteins reflects genetic relatedness between strains; the different patterns obtained from these three species are described and it is shown that this method is very useful in classification and epidemiology.

The in vitro activity of imipenem was determined against 115 isolates of Pseudomonas aeruginosa. The susceptibility was compared according to two technics: disk diffusion method and minimal inhibitory concentration determinations (MIC), this, with three different Mueller Hinton agar (Diagnostics Pasteur, bioMérieux, Amor Equipement Scientifique) and two inocula. There is not inoculum effect. On the contrary, except for extreme values, there is discrepancies in the activity according to the medium. The correlation between zone diameters and MIC values is less good when Mérieux and AES Mueller Hinton agar were used.

The comparative in vitro activity of erythromycin, roxithromycin and doxycycline against 20 isolates of M. avium and 20 M. xenopi was evaluated by two technics: a standard macrobroth dilution (7H9) and the 1% standard proportion method on lowenstein medium. M. avium was highly and uniformly resistant to doxycycline (MIC 50: 64 mg/l). For macrolides some strains were moderately susceptible to roxithromycin and at a lower level to erythromycin the MIC 50 and MIC 90 were respectively 8 and 16 mg/l for roxithromycin, 16 and 64 mg/l for erythromycin. Both macrolides were active against most of the strains of M. xenopi MIC 90 and MBC 90 were respectively 0.25 and 1 mg/l for roxithromycin, 0.5 and 2 mg/l for erythromycin. Doxycycline was less active inhibiting 90% of strains only at 16 mg/l.

The associations of daunorubicin with various antibiotics were studied by the broth dilution method ("checkboard" technic). The FIC Index were calculated to evaluate the effect of the various combinations. Antibiotics tested were chosen according to the bacterial species: vancomycin, cefotaxime, oxacillin, tobramycin, rifampicin against 15 isolates of Staphylococcus, ampicillin, piperacillin, vancomycin, rifampicin against 10 isolates of enterococci, piperacillin, ofloxacin, tobramycin against 5 E. coli strains. No antagonistic effect was observed whatever the antibiotic or bacterial strain. Against enterococci, all combinations showed a synergistic or additive effect, the most pronounced effect being demonstrated with rifampicin (FIC Index value around 0.3). Among the combinations tested against Staphylococcus, the combination daunorubicin + tobramycin demonstrated synergy against all but 1 strain tested, the combinations including oxacillin, cefotaxime or rifampicin showed a synergistic or additive effect, combinations including vancomycin showed addition or no drug interaction. Antibiotics tested against E. coli gave a synergistic combined drug effect in some cases, more often an additive effect, some time no interaction, depending on the strain.