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Resume Mycobacterium bovis, l’agent de la tuberculose bovine, est une zoonose transmissible a l’homme. En France, la prevalence de la tuberculose a M. bovis a nettement diminue chez l’animal et chez l’homme depuis l’introduction des mesures de sante publique destinees a prevenir sa transmission. Cependant, on observe une recrudescence de la maladie au niveau bovin dans certaines regions francaises et plus particulierement en Aquitaine. En 2008, 40 % des cas de tuberculoses bovines recenses en France provenaient de la region Aquitaine. De novembre 2004 a octobre 2008, 15 cas humains ont ete repertories au CHU de Bordeaux, 13 dus a M. bovis et deux a Mycobacterium caprae. Cela represente 2,9 % des tuberculoses dues au complexe tuberculosis. L’analyse des dossiers des 15 patients a permis de montrer qu’il s’agissait soit de sujets âges qui reactivaient une infection ancienne, soit de sujets plus jeunes nes dans des pays de forte endemie de M. bovis. Les formes extrapulmonaires et surtout ganglionnaires sont les plus frequentes. M. caprae semble une espece emergente parmi les mycobacteries animales transmissibles a l’homme. Une surveillance epidemiologique semble necessaire pour etablir une relation entre la recrudescence regionale de la tuberculose bovine et les tuberculoses humaines.

The incidence of nontuberculous mycobacteria (NTM) pulmonary diseases in HIV-negative patients was studied prospectively from January 1, 2001 to December 31, 2003 by 32 sentinel sites distributed throughout France. In total, 262 patients who yielded NTM isolates from respiratory clinical specimens, met the bacteriological, radiological and clinical criteria established by the American Thoracic Society for NTM respiratory disease. Among the 262 NTM isolates, 234 were slow-growing mycobacteria (125 Mycobacterium avium-intracellulare complex (MAC), 66 M. xenopi, 34 M. kansasii) and 28 were rapidly growing mycobacteria (25 M. abscessus complex). In the Paris area, M. xenopi was the most frequently isolated species, followed by MAC. Most patients (>50%), except those with M. kansasii, had underlying predisposing factors such as pre-existing pulmonary disease or immune deficiency. Asthenia, weight loss, chronic cough and dyspnoea were the most common clinical symptoms. The classical radiological appearance of NTM infections was indistinguishable from that observed in patients with pulmonary tuberculosis. In summary, the incidence of nontuberculous mycobacteria pulmonary infections in HIV-negative patients was estimated at 0.74, 0.73 and 0.72 cases per 100,000 inhabitants in 2001, 2002 and 2003, respectively.

Resume Les tuberculoses extrapulmonaires se definissent comme des infections touchant un organe autre que le poumon. En France, elles representent environ 25 % des cas declares de tuberculose. Objectif et methode. – L’objectif de ce travail est d’analyser les differentes techniques bacteriologiques permettant de faire leur diagnostic a travers l’etude des resultats bacteriologiques de 51 patients atteints de tuberculoses extrapulmonaires hospitalises dans un service de medecine interne et de maladies infectieuses. Resultats. – Dans cette etude, le diagnostic de tuberculose extrapulmonaire a ete documente pour 55 % des patients ce qui confirme la difficulte du diagnostic bacteriologique a l’origine des retards diagnostiques. A partir de ce travail, nous montrons la necessite de realiser des prelevements au niveau du site exact correspondant a l’atteinte extrapulmonaire. Les nouvelles methodes d’amplification genique ne semblent pas ameliorer le diagnostic des tuberculoses extrapulmonaires. Dans notre etude, la sensibilite de la PCR par rapport a celle de la culture est de 32 %. Conclusion. – La culture reste donc la methode de reference la plus sensible. L’utilisation des milieux liquides notamment automatises non radioactifs utilisables en routine diminue les delais de culture, limite les contaminations et permet la realisation d’un antibiogramme dont le resultat est obtenu plus rapidement. L’ensemencement conjoint d’un milieu solide et liquide permet d’obtenir une sensibilite maximale et facilite l’identification.

Resume Objectif. – Nous avons voulu apprecier le niveau de resistance du pneumocoque en region Aquitaine. Methode. – Durant l’annee 2001, 716 souches de Streptococcus pneumoniae ont ete repertoriees a partir de 19 laboratoires de microbiologie. Resultats. – Dix-neuf pour cent des souches etaient isoles chez les enfants de moins de 6 ans et 60 % chez les adultes âges de plus de 40 ans. Le pourcentage le plus eleve de souches isolees d’hemoculture appartenait aux patients de plus de 80 ans (38 %), pour les souches isolees de secretions pulmonaires il s’agissait des adultes entre 40 et 80 ans (71 a 75 %) et pour les OMA de l’enfant de moins de 6 ans. Les serotypes 19, 14 et 23 etaient les plus frequents, respectivement 18, 16,6 et 14,6 %. Les serotypes selectionnes dans le vaccin heptavalent couvraient 70 % des souches isolees. Parmi ces 716 souches, 59 % etait de sensibilite diminuee a la penicilline G, 21 % des souches etaient resistantes a la penicilline G, 1,1 % seulement a l’amoxicilline et aucune au cefotaxime et ceftriaxone. Parmi les autres antibiotiques, les taux de resistance etaient de 61,5 % pour l’erythromycine, 27 % pour les tetracyclines et 34,6 % pour le cotrimoxazole. Nous n’avons observe aucune resistance a la vancomycine et la resistance a la rifampicine est rare (0,2 %). Parmi les 504 souches testees, 11 (2,2 %) etaient resistantes aux fluoroquinolones. Commentaire. – L’âge, le sexe masculin et les hospitalisations semblent etre des facteurs de risque de selection de ces souches.

Resume L’augmentation des infections a mycobacteries lors des dernieres decades a attire l’attention sur le temps necessaire au diagnostic, et des progres rapides, en grande partie lies a la biologie moleculaire, ont conduit a une detection et une identification plus rapides de Mycobacterium tuberculosis . La coloration de Ziehl-Neelsen reste la procedure la plus rapide pour detecter les infections, mais elle manque de sensibilite et ne permet pas de distinguer les mycobacteries tuberculeuses des non tuberculeuses. Toutes les nouvelles techniques de culture, automatisees ou non, apparaissent equivalentes dans la detection des mycobacteries, mais la sensibilite optimale est obtenue en combinant milieux liquides et solides. L’hybridation avec les sondes a ADN, faciles a manipuler, realisee a partir des milieux solides ou liquides, est tres performante pour l’identification du complexe tuberculosis . Les techniques de biologie moleculaire ont un reel potentiel dans la detection de la resistance a la rifampicine, mais la faible incidence de la resistance en France et surtout son cout limitent son utilisation. Les techniques d’amplification genique sont capables de detecter directement le complexe tuberculosis dans les produits pathologiques, mais leurs performances sont variables. Dans le cas ou l’examen microscopique est positif, ces techniques permettent d’obtenir rapidement et de facon fiable l’identification du complexe tuberculosis , mais pour l’ensemble des echantillons la sensibilite et la specificite de ces tests d’amplification sont significativement inferieures a celles de la culture qui reste le gold-standard du diagnostic de la tuberculose. Ces techniques, actuellement, restent seulement des tests complementaires pour des patients presentant une forte suspicion de tuberculose clinique.

The purpose of this study was to evaluate the ability of BDProbeTec ET DTB system to detect Mycobacterium tuberculosis complex directly from clinical specimens. A total of 628 specimens (553 respiratory and 75 non respiratory specimens) were collected from 478 patients. These samples were tested with the BDProbeTec ET DTB assay and results were compared with acid fast microscopy and culture. Sixty eight out of 77 culture positive M. tuberculosis complex samples were detected with overall sensitivity and specificity of 89.5% and 98.2% respectively. Overall sensitivity was 100% in smear positive samples and 79% in smear negative samples. After resolution of discrepant results, sensitivity and specificity for respiratory samples were 91.6% and 98.7% respectively. BDProbeTec ET DTB assay demonstrated to be a rapid, sensitive and specific method for detection of M. tuberculosis complex.

Lactivite de la pristinamycine a ete evaluee par la methode de diffusion en agar ou la galerie ATB PNEUMO ainsi que par la determination des CMI en milieu liquide selon les normes du NCCLS vis-a-vis de 749 souches de S. pneumoniae isolees en Aquitaine en 1999. La cinetique de bactericidie de la pristinamycine a ete etudiee vis-a-vis de dix souches de S. pneumoniae sensibles et resistants a l'erythromycine. Toutes les souches testees par la galerie ATB PNEUMO etaient sensibles a la pristinamycine, 6,8 % des souches testees par la methode de diffusion en agar etaient intermediaires ou resistantes. Cependant les CMI de la pristinamycine determinees par la methode des dilutions en milieu liquide vis-a-vis de ces souches etaient < 1 mg/L. Ces resultats suggerent que les diametres d'inhibition sont mal correles avec les CMI pour les pneumocoques resistants a l'erythromycine et que la determination de la CMI est necessaire. Les resultats des courbes de bactericidie montrent une tres bonne et rapide activite bactericide de la pristinamycine en deux heures pour des concentrations egales a 4 x CMI et en quatre heures pour 2 x CMI.

The aim of the present study was to better characterize the expansion of double-negative (DN) T cells in vivo in AIDS patients and to ascertain the discrepant response of an immunodepressed immune system towards two distinct mycobacterial infections. In a large cohort of HIV-1 seropositive patients with low CD4(+) T cell counts (

The disposition of ciprofloxacin in free form and loaded PIBCA/NP has been studied after intravenous infusion to the rabbit. Data from plasma concentration profiles revealed that pharmacokinetic parameters of ciprofloxacin associated with the colloidal carrier were greatly modified. Thus, ciprofloxacin-loaded PIBCA/NP led to increased AUC, t1/2 and Vd, and to a decreased Cl as compared with drug in solution. This could be due not only to the colloidal drug carrier but also to the pharmacokinetics of ciprofloxacin itself. Studies of efficacy against Mycobacterium avium complex in human macrophages proved that ciprofloxacin-loaded PIBCA/NP was more effective than free drug. The cytotoxicity of the polymeric material was observed at concentrations higher than 80 μg of PIBCA per ml with drastic reduction of viable macrophages. This may explain why the efficacy of ciprofloxacin associated with nanoparticles was much lower than expected.

Resume D'octobre 1994 a septembre 1995, 17 laboratoires de Microbiologie d'Aquitaine ont collecte 866 souches de Streptococcus pneumoniae . Le test de sensibilite a l'oxacilline a permis de detecter 33,5 % de souches de S. pneumoniae de sensibilite diminuee a la penicilline G (PSDP). Le pourcentage de PSDP est plus eleve parmi les souches non invasives (34,6 %) mais superieur pour les souches invasives isolees chez l'adulte (31 %) par rapport aux enfants (13 %). La frequence des souches presentant un haut niveau de resistance a la penicilline G (CMI >1 mg/l) est de 22 %. Parmi les PSDP, les serogroupes ou serotypes prevalents par ordre de frequence sont les 23F, 14 et 9. Tres souvent, les PSDP presentent une resistance associee a l'erythromycine (65,5 %), tetracyclines (36,8 %), cotrimoxazole (74,2 %) et chloramphenicol (44,3 %). La determination des CMI par la methode des dilutions en milieu gelose montre que l'imipeneme est l'agent le plus actif, mais cefotaxime, ceftriaxone et cefpirome sont seulement un peu moins efficaces. Parmi les beta-lactamines orales, l'amoxicilline et le cefpodoxime restent les plus actives sur les souches de sensibilite intermediaire alors que les autres cephalosporines orales montrent frequemment un haut niveau de resistance.

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 "Epidemiologie 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.

Resume Mycobacterium malmoense agent frequent de mycobacteriose en Suede, Finlande et Grande-Bretagne, reste rare en France (2 infections pulmonaires en 1983 et 1986). L'infection est generalement pulmonaire chez l'adulte et ganglionnaire chez l'enfant ; les autres infections (disseminees, cutanees ou des tissus mous) sont rares et concernent surtout des immuno-deprimes. Ces infections restent exceptionnelles chez les malades atteints de SIDA. Le traitement n'est pas codifie. Les associations les plus utilisees comprennent isoniazide, rifampicine et ethambutol ; l'efficacite in vivo de la clarithromycine n'est pas documentee. Le diagnostic est rendu difficile par la croissance lente (6 a 8 semaines) et dysgonique sur milieu solide. Cependant la culture peut etre detectee en 8 jours par methode Bactec. Les tests biochimiques caracteristiques sont l'hydrolyse du Tween 80 a 10 jours et la catalase thermolabile. La composition en acides mycoliques et la presence d'acides gras ramifies en 21 et 27 atomes de carbone constituent des marqueurs specifiques d'espece. Nous presentons ici 8 cas francais (6 infections pulmonaires dont une chez un malade VIH positif, 1 adenopathie cervicale, 1 infection cutanee) de mycobacterioses dues a M. malmoense , diagnostiquees de 1989 a 1992.

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.

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.

The incidence of Mycobacterium avium complex (MAC) pulmonary disease in HIV-negative patients was studied prospectively from January 1, 2000 to December 31, 2002 through 32 sentinel sites distributed all over France. Among the 275 patients who yielded MAC isolates from respiratory clinical specimens, 101 (36.7%) met the bacteriological, radiographical and clinical criteria established by the American Thoracic Society for nontuberculous mycobacterial respiratory disease. Of these 101 patients, 81 had underlying lung disease, mainly previous tuberculosis, bronchectasis or chronic obstructive pulmonary disease. Among the 20 patients with no underlying lung disease, 12 had a predisposing factor such as leukaemia or immunosuppressive treatment and eight had no predisposing factor. All patients with MAC respiratory disease had clinical symptoms, commonly cough and fatigue, and 52 (51.5%) were sputum smear positive for acid-fast bacillus. The ratio of patients with Mycobacterium avium complex pulmonary disease to patients with pulmonary tuberculosis in France was estimated to be 3% and the incidence of Mycobacterium avium complex pulmonary disease in France was 0.2 per 100,000 inhabitants.

Extrapulmonary tuberculosis is usually more difficult to diagnose than pulmonary tuberculosis. It often involves inaccessible sites and it is paucibacillary.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.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.

Stenotrophomonas maltophilia (S. maltophilia) is an important cause of nosocomial infection among ventilated and immunocompromised patients, and among patients receiving broad-spectrum antimicrobials. We report a cluster of patients in a surgical intensive care unit who were colonized or infected with S. maltophilia. An epidemiological investigation was initiated after surveillance data revealed that eight patients were culture-positive from sputum for S. maltophilia in the preceding month. Review of respiratory care procedures revealed that when mechanical ventilators were serviced between patients, the electronic temperature probes used with servo-controlled humidifiers were wiped with inadequate disinfection. We collected cultures of case-patient room surfaces, sinks and ventilator equipment. S. maltophilia was recovered from room surfaces, ventilator expiratory circuits and a temperature sensor which had been kept in ambient air after disinfection. Patients and environmental isolates were examined by RAPD-PCR. Three clinical isolates and one environmental isolate had the same profile, which suggests cross-contamination or common source exposure. The outbreak was controlled by adequate disinfection of the temperature sensors. No single epidemic strain was identified but several observations support the conclusion that the temperature probes contributed to the outbreak.

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 were1 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.

The Amplicor Mycobacterium tuberculosis test is a new PCR assay for the direct detection of Mycobacterium tuberculosis from clinical samples. A multicenter study that included six laboratories was done to evaluate the Amplicor test in comparison with direct microscopy and culture (solid or radiometric media), and the culture method was used as the "gold standard." A total of 2,073 specimens, i.e., 1,749 respiratory specimens and 324 other specimens, were tested. A total of 184 cultures yielded M. tuberculosis. Of these 184 cultures, 77 (42%) were smear negative and 23 (12.5%) concerned extrapulmonary specimens. The sensitivity of the Amplicor test for all of the specimens and for extrapulmonary, smear-positive, and smear-negative specimens was 86, 83, 94.5, and 74%, respectively. The sensitivity of direct microscopy in comparison with that of culture was 58%. A total of 95% of patients with culture-proven tuberculosis were diagnosed by the Amplicor test, whereas direct microscopy detected mycobacteria in only 72% of these patients. The Amplicor test exhibited a high degree of specificity (98%). The assay was very rapid and easy to perform.

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 (MIC1 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.

Introduction et objectifs Les mycobacteries non tuberculeuses (MNT) sont responsables chez l’homme d’infections respiratoires ou d’atteintes cutanees. Leur traitement implique une association d’antibiotiques, variable selon l’espece en cause. L’objectif de ce travail est d’etudier la sensibilite de trois especes de MNT a six antibiotiques utilises en therapeutique. Materiels et methodes 17 souches de M. abcessus isolees d’infections pulmonaires ainsi que 23 souches de M. marinum et 5 souches de M. chelonae isolees d’infections cutanees entre janvier 2004 et decembre 2008 ont ete testees. Les concentrations minimales inhibitrices (CMI) de la clarithromycine, de l’amikacine, de la ciprofloxacine, de la moxifloxacine, de la tigecycline et du linezolide ont ete realisees en milieu gelose, selon les recommandations du NCCLS. Resultats Toutes les souches de M. abcessus testees sont resistantes a l’amikacine (CMI : 32 μg/ml), a la ciprofloxacine (CMI : 2 - > 8 μg/ml), a la moxifloxacine (CMI : 4 - > 8 μg/ml) et au linezolide (CMI : 16 - 32 μg/ml). Les souches de M. chelonae presentent le meme phenotype de resistance, avec cependant des cmI plus faibles pour la ciprofloxacine et la moxifloxacine (2 - 4 μg/ml). La clarithromycine et la tigecycline sont les molecules les plus actives sur ces deux especes, avec des cmI allant de 0,5 a 2 μg/ml. M. marinum est une espece sensible aux six antibiotiques testes, le linezolide presentant des CMI plus faibles (0,25 - 1 μg/ml) que la tigecycline. Conclusion Cette etude montre que la clarithromycine reste la molecule la plus efficace sur l’ensemble des especes de MNT testees mais parmi les nouvelles molecules, le linezolide pourrait avoir une place dans le traitement des infections cutanees a M. marinum et la tigecycline dans les infections pulmonaires a M. abcessus.

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.

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.

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.

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.

Preliminary results of this study were presented at the European Congress of Clinical Microbiology and Infectious Diseases, Helsinki, Finland, 16-19 May 2009; International audience; Mycobacterium genavense, a nontuberculous mycobacteri-um, led to devastating infections in patients with acquired immunode-ficiency syndrome (AIDS) before highly active antiretroviral therapy (HAART) was available, as well as in other immunocompromised patients. We conducted the current study to describe the features of this infection in patients infected with human immunodeficiency virus (HIV) in the HAART era and in non HIV-infected patients. We conducted a retrospective cohort survey in France. All patients with M. genavense infection diagnosed from 1996 to 2007 at the National Reference Center, Institut Pasteur, Paris, were identified and their clinical, laboratory, and microbiologic data were centralized in a single database. Twenty-five cases of M. genavense infection originating from 19 centers were identified. Twenty patients had AIDS, 3 had solid organ transplantation, and 2 had sarcoidosis. Sixty-four percent (n = 16) were male, mean age was 42 years, and median CD4 count was 13/mm 3 (range, 0Y148/mm 3) in patients with AIDS. Twenty-four patients had disseminated infection with fever (75%, n = 18), weight loss (79%, n = 19), abdominal pain (71%, n = 17), diarrhea (62.5%, n = 15), splenomegaly (71%, n = 17), hepatomegaly (62.5%, n = 15), or abdominal adenopathy (62.5%, n = 15). M. genavense was isolated from the lymph node (n = 13), intestinal biopsy (n = 9), blood (n = 6), sputum (n = 3), stool (n = 3), and bone marrow (n = 5). Eleven patients (44%) died, 8 (32%) were considered cured with no residual symptoms, and 6 (24%) had chronic symptoms. The 1-year survival rate was 72%. The prognosis of M. genavense infection in HIV-infected patients has dramatically improved with HAART. Clinical presentations in HIV and non-HIV immunocompromised patients were similar. (Medicine 2011;90: 223Y230) Abbreviations: AFB = acid-fast bacilli, AIDS = acquired immuno-deficiency syndrome, HAART = highly active antiretroviral therapy, HIV = human immunodeficiency virus, SOT = solid organ transplant.