Multidrug-resistant infections in long-term care facilities: extended-spectrum ß-lactamase-producing Enterobacteriaceae and hypervirulent antibiotic resistant Clostridium difficile.

Infections due to multidrug-resistant (MDR) organisms in long-term care facilities (LTCFs) residents constitute a public health concern. This multicenter study investigated the frequency of ESBL-producing pathogens and MDR Clostridium difficile in clinical specimens from LTCF residents in Italy. During October 2014-March 2015, all urine and diarrheic fecal samples from LTCF residents (≥65 years) with suspected urinary tract infection or C. difficile infection, respectively, received for diagnosis by 4 hospital laboratories located in different cities were analyzed. Antibiotic susceptibility testing, characterization of resistance genes, and molecular typing of pathogens were performed. Of 806 urine cultures collected from 626 residents at 44 different LTCFs, 492 were positive for microbial infection. Of these, 158 were positive for at least an ESBL-producing Enterobacteriaceae species (32.1%), with Escherichia coli as the most frequent ESBL pathogen (23.4%) followed by Klebsiella pneumoniae (4.5%). Furthermore, 4 carbapenemase producers (0.8%) (1 E. coli with VIM-1and 3 K. pneumoniae with KPC-3) were detected. The CTX-M-15 type ESBL predominated in both E. coli (71.3%) and K. pneumoniae (77.3%). Most E. coli isolates (82.6%) belonged to the ST131/H30 clone/subclone. For K. pneumoniae, ST307 and ST15 were frequent (31.8% and 22.7%, respectively), but isolates harboring blaKPC-3 belonged to CC258. Of 136 diarrheic fecal samples collected from 111 residents at 26 different LTCFs, 21 (15.4%) were positive for toxigenic C. difficile; of these, 13 (62%) were MDR (resistant to 3 or more antimicrobial agents of different classes). The predominant C. difficile polymerase chain reaction ribotype was 356/607 (42.9%), followed by 018, 449, and 078 (14% each). Public health efforts are needed to contain the diffusion of CTX-M-producing Enterobacteriaceae and MDR C. difficile in LTCF settings.

Direct identification of microorganisms from positive blood cultures using the lysis-filtration technique and matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS): a multicentre study.

Microbial identification from blood cultures is essential to institute optimal antibiotic therapy and improve survival possibilities. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been successfully applied to identify bacteria and yeasts from positive blood cultures broths. The aim of this multicentre study was to evaluate the reliability of the lysis-filtration technique associated with MALDI-TOF MS to directly identify microorganisms from 765 positive blood cultures collected in six Italian hospitals. Overall, 675/765 (78.1%) blood isolates were correctly identified at the species level, with significant differences between Gram-negative and Gram-positive bacteria (92.6%, and 69.8%, respectively). Some difficulties arise in identifying Streptococcus pneumoniae, Staphylococcus aureus, yeasts and anaerobes. The lysis-filtration protocol is a suitable procedure in terms of performance in identifying microorganisms, but it is quite expensive and technically time-consuming since the time of filtration is not regular for all the samples. The application of the MALDI-TOF MS technique to the direct microbial identification from positive blood cultures is a very promising approach, even if more experience must be gained to minimize errors and costs.

Report of two cases of influenza virus A/H1N1v and B co-infection during the 2010/2011 epidemics in the Italian Veneto Region.

From October 2010 to April 2011, in the Italian Veneto Region, 1403 hospitalized patients were tested for influenza virus infection by specific real time RT-PCR. Overall, 327 samples were positive for either influenza A (75%) or B (25%) viruses. Among these positive patients two resulted co-infected by A/H1N1v and B viruses. Even though co-infection with both influenza A and B viruses appears to be a rare event, it occurs naturally and may play a role in epidemiology and pathogenicity. In the present study the two co-infected patients were a transplant recipient immunocompromised adult and a child displaying a severe respiratory illness. The co-infection was confirmed by inoculation of the nasopharyngeal swabs in MDCK.2 cells, followed by immunofluorescence and real time RT-PCR assays. Moreover, in the case of the adult patient, the immune system response against both viruses was assayed by hemoagglutination inhibition test against reference influenza virus strains. Both patients fully recovered from infection, without significant differences with mono-infected patients.