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In order to identify and define a diagnostic algorithm for the diagnosis of C. difficile infection, a comparative study was carried out at the Microbiology Laboratory of “Maggiore della Carità” Hospital in Novara.We compared the system currently in use in the laboratory “TECHLAB C.difficile Quik Chek Complete (Inverness Medical, USA)”, an immunoenzymatic assay for the simultaneous detection of C. difficile common antigen (GDH) and Toxins A&B, with the new ImmunoCard Clostridium difficile GDH (Meridian Bioscience, USA), which identifies the C. difficile Common Antigen GDH. The results proved identical between the two assays: of 100 samples, 82 resulted negative with both tests, 18 were GDH positive with both tests. Out of the 18 GDH positives, 9 resulted positive for the Toxins portion of the TechLab test.

Introduction: The bone and joint infections sustained by mycobacteria and mainly involving the synovium, tendons and bone stock, may be traumatic, especially in open fractures or iatrogenic post surgical procedures. Methods: The frustules, taken after cleaning the bone, were sent to the Microbiological Laboratory and processed for the presence of Gram-positive and Gram-negative bacterial populations, the mycobacteria Group M. tuberculosis complex and the mycobacteria belonging to the group of NTM (Non Tubercular Mycobacteria). Results: The decontaminated material was sown on liquid culture (MGIT 960 System BD Diagnostics) and on solid growth medium (Löwenstein-Jensen) and kept under observation at 37° C for 60 days. After 15 days on the solid medium there developed a mycobacterium strongly pigmented in orange. By the reverse hybridization method “GenoType® CM; Hain Diagnostika, Nehren, Germany; Arnika”, Mycobacterium szulgai was identified, an organism rarely isolated in our laboratory. On preliminary characterization it resulted scotochromogenic at 37° C and photochromogenic when cultured at 25° C. Conclusions: The isolation of M. szulgai, and the previous isolation of a M. intracellular (paper in press) from a similar material suggest that, in this type of infection, the role of mycobacteria can be clinically relevant and probably underestimated, both because the difficulty of isolating and identifying these organisms and because surgeons almost never request this type of investigation. It would therefore be appropriate to send routinely these materials to dedicated laboratories equipped to search for mycobacteria. Its identification could allow a more realistic picture on the role played by these bacterial infections in osteoarticular infections.

Chlamydia trachomatis infections represent the most common sexually transmitted diseases.The lack of growth of these microorganisms on common media and the roundabout research by immunofluorescence, has meant that, until now, these special-lived intracellular microorganisms have played a role probably underestimated in cases of infections affecting the sexual organs.The introduction of molecular biology has made possible their research in a much more simple, reliable and standardized methods. The study was carried out on endocervical samples, male urethral swabs and urine samples of men and women, determining the C. trachomatis DNA amplified using the BD ProbeTec ET system. This system uses technology SDA (Strand Displacement Amplification - Elongationcrowding of the blanks). The study was conducted from June 2008 to june 2009. Symptomatic and asyntptomatic patients residents in the provinces of Novara and the Verbano-Cusio-Ossola were considered. In this period 784 determinations were made in molecular biology. Chlamydia trachomatis was found in 26 cases equal to a percentage of 3.32%. While considering these preliminary data, however, we can estimate the rate of detection of C. trachomatis as a good starting point, because we have the impression that improved procedures particularly relate to the techniques for sampling and for storage and transport of the sample, can undoubtedly lead to much higher percentages.

From June 2004 to June 2005, a total of 58 mycobacterial isolates were recovered from inpatients admitted to the “Ospedale Maggiore” in Novara, Italy. Most of the above strains were from respiratory secretions. Among the 32 isolates identified as Mycobacterium tuberculosis complex (MTC), susceptibility testing to streptomycin, isoniazid, rifampin, ethambutol and pyrazinamide was subsequently performed by using the MGIT 960 system. Starting from positive cultures, the Genotype MTBDR “Arnika” test, based on target amplification and stripbased reverse hybridization was also carried out. In addition to the MTC identification, the test can investigate the resistance to both rifampin (by molecular analysis of the rpoB region) and isoniazid (by detecting mutations at the resistance domain of katG gene). The results were compared with those obtained by conventional liquid medium susceptibility testing. Full agreement with both drugs was obtained on all the tested isolates. In conclusion, the GenoType MTBDR assay was found to enable a very rapid resistance detection of the most important anti-tubercular drugs.These data are important to set up an effective therapy and consequent disease control.

Central venous catheter represents a major source of nosocomial bloodstream infection, which cause considerable excess morbidity.The diagnosis of catheter-related infections relies on the presence of clinical manifestation of infection and the evidence of colonization of the catheter tip by bacteria or fungi. The most frequent pathogens were Gram-positive organisms, mainly coagulase negative staphylococci, followed by Gram-negative and mycetes. During the years 2001-2003 we examined 2079 vascular catheters, of which 896 were positive for bacterial and fungal species. Of these, 675 (75,3%) involved Gram-positive bacterial, 145 (16,2%) Gram-negative and 76 (8,5%) mycetes.

In thIe latter years Enterobacter cloacae has been counted as a very important occasional pathogen, above all in causing hospital infections.The micro-organism’s interesting increases because of its high resistance in vitro to many antimicrobial agents. For this reason it would be possible to find out others resistance mutant phenotypes. The results (2000-2001 and the first six months of 2002), carried out 341 isolated samples from hospital patients, show that the percentage of these E. cloacae is little more than 1%, increasing prevalence of patients belonging to General Surgery and Intensive Care Unit. The susceptible tests suggest (without important differences during the whole year) that most of the clinical isolates have moderate or high level resistance to various antimicrobial agents (penicillins, cephalosporins, aminoglycosides, quinolones, monobactam) and almost all were susceptible to amikacin, carbapenems (imipenem) and trimethoprim/sulfmamethoxazolo. Always regarding the resistance of these pathogens, it was possible to find out some phenotypes, and one of these, among 172 isolates belonging to Intensive Care Unit, was a particular multiresistance phenotype. The VITEK ESßL detection test and the conventional double disk synergy test for detection of ESßL find out some phenotypes showing expression of stably derepressed beta-lactamase.