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Microbiological Identification (microbiological + identification)
Selected AbstractsPCR identification of Rhizobium radiobacter in post-operative endophthalmitisACTA OPHTHALMOLOGICA, Issue 2007V VINH Purpose: To present 2 cases of PCR identification of Rhizobium radiobacter in post-operative endophthalmitis. Methods: Microbiological identification was carried out using samples from aqueous humor and/or vitreous. Conventional cultures were performed using a Brain Heart Infusion broth. We used broad-range eubacterial PCR amplification followed by direct sequencing. Results: In both cases, Rhizobium radiobacter was identified using eubacterial PCR and cultures of vitreous from vitreous tap. An 81-year-old female presented an endophthalmitis 4 weeks after an cataract surgery. Inflammation and infection were controlled after 2 intravitreal antibiotic injections and the final visual acuity was of 20/24 at the one-year follow-up exam. A 75-year-old male who underwent a cataract surgery presented an endophthalmitis 9 days after. This patient was treated by 3 intravitreal antibiotic injections and a vitrectomy. The 6-month follow-up exam showed an optic nerve atrophy with a poor visual outcome (20/120). Both patients had an initial marked anterior chamber inflammation with a hypopyon and a severe retinal vasculitis was observed in the second case. Conclusions: Rhizobium radiobacter is a rare pathogen involved in postoperative endophthalmitis. As it is an environmental soil organism, we may assume that the patient's exposure to outdoor environnement and moist soil remains the source of this organism. This gram negative rod is resistant to vancomycin and have an intermediate resistance to most antibiotics used to treat post-operative endophthalmitis. PCR allows a swifter bacterial identification than do cultures and may help choose the most efficient antibiotics. [source] Clinical and Microbiological Determinants of Ailing Dental ImplantsCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2009Giorgio Tabanella DDS ABSTRACT Background: The failure of the host tissue to establish or maintain osseointegration around dental implants is due to either occlusal or parafunctional forces, premature loading, ill-directed stress, or microbial infection. The long-term failure rate of dental implants is generally 5,10%. Although a variety of etiologies of early peri-implant bone loss (from implant placement to 1-year post-loading) have been proposed, factors associated with late implant failures are less well understood but are probably related to both the peri-implant microbial environment and host factors. Discriminating between causes of implant failure is of importance for instituting a successful implant therapy. Purpose: The objective of this cross-sectional split-mouth study was to identify clinical, radiographic, and bacterial characteristics of peri-implant disease sites. Materials and Methods: Fifteen patients with bilateral implants (Brånemark®, Nobel Biocare AB, Göteborg, Sweden; and 3iÔ implant systems, Implant Innovations Inc., Palm Beach Gardens, FL, USA) participated in the study. Sites with peri-implantitis (radiographic bone loss beyond the third implant thread) and peri-implant healthy tissues (radiographic bone level above the first implant thread) were identified in periapical radiographs using a long-cone paralleling projection technique. Microbiological identification was carried out using established anaerobic culture techniques. A descriptive statistics based on means and standard deviations was reported. Results: Peri-implant bone loss was associated with the absence of radiographic crestal lamina dura, peri-implant pocket depth, pain on chewing, and the submucosal presence of the putative periodontopathogens Tannerella forsythia, Campylobacter species, and Peptostreptococcus micros. Pain was associated with P. micros, Fusobacterium species, and Eubacterium species. Discussion and Conclusion: The absence of radiographic crestal lamina dura and the presence of suspected major periodontal pathogens seem to be associated to peri-implantitis. [source] Real-time polymerase chain-reaction detection of pathogens is feasible to supplement the diagnostic sequence for urinary tract infectionsBJU INTERNATIONAL, Issue 1 2010Lutz E. Lehmann OBJECTIVE To evaluate, in a prospective pilot study, the feasibility of identifying pathogens in urine using real-time polymerase chain reaction (PCR), and to compare the results with the conventional urine culture-based procedures. PATIENTS AND METHODS Severe urinary tract infections (UTIs) are frequent in critically ill patients in the intensive-care unit (ICU) and in outpatients, and thus the reliable and fast identification of the bacteria is mandatory, but routine urine culture is time-consuming and the therapeutic regimen is often calculated and not culture-based. The study included 301 prospectively collected urine samples from 189 patients with suspected UTI, based in a university hospital in 2005, and included outpatients and those in the ICU. Urine culture with Cled-, MacConkey- and malt extract agar of all samples was followed by microbiological identification of the pathogens in 98 samples with visible growth. In parallel, all samples were assessed using qualitative real-time PCR-based DNA detection and identification by labelled hybridization probes. RESULTS In all, 15 dipstick culture-negative samples showed positive pathogen DNA identification by PCR. By contrast, 17 PCR-negative samples showed detectable pathogens by culture, of which 10 were not detectable on PCR because the identified pathogens were not represented in the probe panel. The sensitivity and specificity for detecting contaminated samples was 0.90 and 0.87, respectively. Overall, 95% of the mono-infection pathogens and 57% of the multiple-infection pathogens were detected concordantly with both methods. CONCLUSION In this prospective pilot study PCR-based identification of pathogens was feasible for supplementing conventional culture methods for the diagnosis of UTI. The main advantage is the time saved in identifying the pathogens. The limited pathogen detection in multiple-infection-samples by PCR might be explained by competitive PCR amplification conditions. [source] Predictive factors of visual outcome in acute post-cataract endophthalmitisACTA OPHTHALMOLOGICA, Issue 2009A COMBEY-DE LAMBERT Purpose To study potential clinical and microbiological predictive factors of visual outcome in patients with acute endophthalmitis following cataract surgery. Methods A prospective study included 100 patients in 4 University hospital.Factors related to the cataract surgery, the initial clinical presentation and the microbiological identification were analyzed according to the final visual outcome using univariate and multivariate (logistic regression) analysis. Results 46% out of the patients had a final visual acuity less than or equal to 0.3 logMar (good visual outcome) at 6 months while 10% had only light perceptions. Patients with good visual outcome differed for the duration of cataract surgery, initial visual acuity, the visibility of fundus and the identification of a coagulase negative staphylococcus. In contrast, patients with a poor visual outcome were older, had more cornea oedema and a more important hypopion at the admission, more complications at the time of cataract surgery. Furthermore a bacterium was more frequently identified in this latter group. Multivariate analysis showed that age, complications at the time of cataract surgery, microbiological identification, pars plana vitrectomy were independent predictive factors. Conclusion Factors of visual outcome in acute postcataract endophthalmitis identified in this prospective study were similar to that reported during the Endophthalmitis Vitrectomy Study 10 years ago. As part of the treatment, pars plana vitrectomy is associated with predictive factors of poor visual outcome. Identification of these predictive factors at presentation should allow a better management of patients needed an aggressive treatment. [source] Antimicrobial treatment of presumed ocular tuberculosisACTA OPHTHALMOLOGICA, Issue 2007S KOUPRIANOFF Purpose: Uveitis secondary to a tuberculosis is rarely reported, even in a tertiary a care center. The prevalence of tuberculosis is low in Western Europe and its microbiological identification is difficult. However, anti tuberculosis treatment may be useful when the diagnosis of tuberculosis is presumed. Methods: The clinical records of patients with suspected tuberculosis uveitis referred to the Ophthalmology Department of the Grenoble University, between January 2005 and January 2007 were retrospectively analyzed. Patients were included in this series if they received a specific antituberculosis treatment. Results: This series included 10 patients (3M/7F, mean age 54.1). The clinical features of ocular inflammation were: bilateral panuveitis, episcleritis, bilateral posterior uveitis, and pars planitis. Tuberculin skin test, chest computerized tomography, BK sputum, and internal medicine consultation were performed for all patients. The diagnosis of presumed tuberculosis was based upon: history, thoracic imaging, and tuberculin skin test. None had extra-ocular symptoms. Sputum cultures were negative, 2 adenopathy biopsies confirmed the diagnosis. Nine patients received specific antituberculosis therapy, without systemic steroid therapy. All of them improved; no relapse occurred after 1 to 2 years after the end of therapy. In one case, tuberculosis specific therapy allowed to taper the systemic steroid therapy. Conclusions: The diagnosis of uveitis associated with tuberculosis is difficult since it depends on a spectrum of indirect signs. Bacteriological identification is rarely obtained. In presumed ocular tuberculosis, antituberculosis therapy may be useful to control intraocular inflammation, with or without steroid therapy. [source] Mycobacterial infection in a series of 1261 renal transplant recipientsCLINICAL MICROBIOLOGY AND INFECTION, Issue 6 2003J. A. Queipo Objective To describe the incidence and clinical characteristics of mycobacterial infection in renal transplant recipients. Methods We retrospectively analyzed the cases of mycobacterial infection in a series of 1261 renal transplants carried out in our Unit of Renal Transplantation from 1980 to 2000. Demographic parameters and clinical antecedents such as age, cause of end-stage renal disease, time of follow-up of the graft, previous renal function and type of immunosuppression were considered. Moreover, the clinical onset, diagnostic tools, treatment policy and evolution were studied. The pathogenesis of the different types of mycobacteria isolated was also analyzed. Diagnosis was made with the Ziehl,Neelsen staining method. Culture was performed by the conventional Löwenstein,Jensen method and the Bactec-460 radiometric method. Results We found mycobacterial infection in 27 patients (2.1%), due to Mycobacterium tuberculosis in 20 cases, M. kansasii in five patients, and M. fortuitum in two patients. The mean elapsed time from the renal transplant was 20.5 months; the infection appeared in 18 patients during the first eight months after transplantation. The clinical onset was pulmonary infection in 17 cases (12 M. tuberculosis and five M. kansasii); five had urinary symptoms (three M. tuberculosis and two M. fortuitum); three cases of M. tuberculosis infection had abdominal symptoms; another one began with a perineal tuberculous abscess; the rest of the patients were asymptomatic. The types of specimen on which microbiological identification was carried out were, in decreasing order: sputum and/or bronchial washing/pleural aspiration, urine, feces, gastric and peritoneal fluids, bone marrow and blood. The first-line drug isoniazid had the highest resistance index in the susceptibility test. Clinical dissemination was observed in eight patients, four of whom died. Another three patients had a significant impairment in renal function, and in one of these patients an allograft nephrectomy was necessary due to a severe septic syndrome. Conclusions Mycobacterial infection, mainly by M. tuberculosis, has an important impact on kidney transplant recipients, particularly during the first year after surgery. Diagnosis often presents some difficulties, and a delay in treatment represents a determinant factor for the evolution, with a risk of death or permanent damage in renal function. Therefore, early diagnosis is mandatory. When the Mantoux reaction is positive, antituberculous prophylaxis seems advisable. [source] | ||||||||||