Of the Klebsiella sp. isolates, 54.9% were resistant to third-generation cephalosporins. Of the Acinetobacter spp. and Pseudomonas aeruginosa isolates, 55.9% and 36.8%, respectively, were resistant to imipenem. In our multicenter study, we found high crude mortality and a high proportion of nBSIs due to antibiotic-resistant organisms.

The new assay was able to detect the presence of six different carbapenemase gene types in a single 3 h PCR.

Metallo-␤-lactamase enzymes (M␤L) are encoded by transferable genes, which appear to spread rapidly among gram-negative bacteria. The objective of this study was to develop a multiplex real-time PCR assay followed by a melt curve step for rapid detection and identification of genes encoding M␤L-type enzymes based on the amplicon melting peak. The reference sequences of all genes encoding IMP and VIM types, SPM-1, GIM-1, and SIM-1 were downloaded from GenBank, and primers were designed to obtain amplicons showing different sizes and melting peak temperatures (T m ). The real-time PCR assay was able to detect all M␤L-harboring clinical isolates, and the T m -assigned genotypes were 100% coincident with previous sequencing results. This assay could be suitable for identification of M␤L-producing gram-negative bacteria by molecular diagnostic laboratories.Since the first report of acquired metallo-␤-lactamase (M␤L) in Japan in 1994 (15), genes encoding IMP-and VIMtype enzymes have spread rapidly among Pseudomonas spp. (1,5,10,13,14,16,18,(22)(23)(24), Acinetobacter spp. (3,4,17,21,29), and strains of Enterobacteriaceae (6,8,11,12,20,28). Moreover, new M␤L types have been described, such as SPM (25), GIM (2), and, more recently, SIM (9).The prevalence of M␤L-producing gram-negative bacilli has increased in some hospitals, particularly among clinical isolates of Pseudomonas aeruginosa and Acinetobacter spp. (21,23,27). Since M␤L production may confer phenotypic resistance to virtually all clinically available ␤-lactams, the continued spread of M␤L is a major clinical concern (26). The aim of this study was to develop a multiplex real-time PCR assay followed by a melt curve step for rapid detection and identification of genes encoding the M␤L-type enzymes so far described. The M␤L type identification was based on the characteristic amplicon melting peak. MATERIALS AND METHODS M␤L-harboring clinical isolates and M␤L-negative control strains.The strains used in this study are listed in Tables 1 and 2. The M␤L genotypes of the clinical isolates of gram-negative nonfermentative and fermentative bacteria harboring M␤L were previously characterized by PCR and sequencing. When applicable, these clinical isolates were also previously molecularly typed to ensure that genetically unrelated strains were used. Additionally, several American Type Culture Collection (ATCC; Manassas, VA) reference strains and laboratory strains were used as M␤L-negative controls (Table 2).DNA preparation. The microorganisms were grown on blood agar plates overnight at 37°C to ensure colony purity. Three or four bacterial colonies were taken from the blood agar plates and suspended in 200 l of DNase/RNase-free distilled water (Invitrogen, CA). Two microliters of this suspension was used as templates for further amplification.Primer design. The currently available reference sequences of the M␤L-encoding IMP-and VIM-type (http://www.lahey.org/studies/), SPM-1 (AJ492820), GIM-1 (AJ620678), and SIM-1 (AY887066) genes were downloaded from GenBank (National...

Candidemia is a growing problem in hospitals all over the world. Despite advances in the medical support of critically ill patients, candidiasis leads to prolonged hospitalization, and has a crude mortality rate around 50%. We conducted a multicenter surveillance study in 16 hospitals distributed across five regions of Brazil to assess the incidence, species distribution, antifungal susceptibility, and risk factors for bloodstream infections due to Candida species. From June 2007 to March 2010, we studied a total of 2,563 nosocomial bloodstream infection (nBSI) episodes. Candida spp. was the 7th most prevalent agent. Most of the patients were male, with a median age of 56 years. A total of 64 patients (46.7%) were in the ICU when candidemia occurred. Malignancies were the most common underlying condition (32%). The crude mortality rate of candidemia during the hospital admission was 72.2%. Non-albicans species of Candida accounted for 65.7% of the 137 yeast isolates. C. albicans (34.3%), Candida parapsilosis (24.1%), Candida tropicalis (15.3%) and Candida glabrata (10.2%) were the most prevalent species. Only 47 out of 137 Candida isolates were sent to the reference laboratory for antifungal susceptibility testing. All C. albicans, C. tropicalis and C. parapsilosis isolates were susceptible to the 5 antifungal drugs tested. Among 11 C. glabrata isolates, 36% were resistant to fluconazole, and 64% SDD. All of them were susceptible to anidulafungin and amphotericin B. We observed that C. glabrata is emerging as a major player among non-albicans Candida spp. and fluconazole resistance was primarily confined to C. glabrata and C. krusei strains. Candida resistance to echinocandins and amphotericin B remains rare in Brazil.Mortality rates remain increasingly higher than that observed in the Northern Hemisphere countries, emphasizing the need for improving local practices of clinical management of candidemia, including early diagnosis, source control and precise antifungal therapy.

Emerging resistance phenotypes and antimicrobial resistance rates among pathogens recovered from community-acquired urinary tract infections (CA-UTI) is an increasing problem in specific regions

The alarming emergence and spread of antimicrobial resistance among common bacteria threatens the effectiveness of therapy for many infections. Surveillance of antimicrobial resistance is essential to identify the major problems and guide adequate control measures. Several resistance surveillance programs have been implemented in North America and Europe in the last decade; however, very few programs have assessed antimicrobial resistance in Latin American countries. The SENTRY Antimicrobial Surveillance Program was initiated in 1997 and represents the most comprehensive surveillance program in place at the present time worldwide. The SENTRY Program collects consecutive isolates from clinically documented infections in more than 80 medical centers worldwide (10 in Latin America). The isolates are collected according to the type of infection (objectives) and susceptibility tested in a central microbiology laboratory by reference broth microdilution methods according to NCCLS guidelines. The Program also incorporated molecular typing (ribotyping and PFGE) and resistance mechanism analysis of selected isolates. In this report we present a very broad analysis of the data generated by testing almost 20,000 bacterial isolates against more than 30 antimicrobial agents. The susceptibility results (MIC(50), MIC(90) and % susceptible) are presented in 11 tables according to the organism and site of infection. The data from Brazil, as well as the data from isolates collected in 2001, are analyzed separately. This report allows the evaluation of the activities numerous antimicrobial agents against clinical isolates collected in Latin American countries.

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