An epidemic of infections after video-assisted surgery (1,051 possible cases) caused by rapidly growing mycobacteria (RGM) and involving 63 hospitals in the state of Rio de Janeiro, Brazil, occurred between August 2006 and July 2007. One hundred ninety-seven cases were confirmed by positive acid-fast staining and/or culture techniques. Thirty-eight hospitals had cases confirmed by mycobacterial culture, with a total of 148 available isolates recovered from 146 patients. Most (n ‫؍‬ 144; 97.2%) isolates presented a PRA-hsp65 restriction pattern suggestive of Mycobacterium bolletii or Mycobacterium massiliense. Seventy-four of these isolates were further identified by hsp65 or rpoB partial sequencing, confirming the species identification as M. massiliense. Epidemic isolates showed susceptibility to amikacin (MIC at which 90% of the tested isolates are inhibited [MIC 90 ], 8 g/ml) and clarithromycin (MIC 90 , 0.25 g/ml) but resistance to ciprofloxacin (MIC 90 , >32 g/ml), cefoxitin (MIC 90 , 128 g/ml), and doxycycline (MIC 90 , >64 g/ml). Representative epidemic M. massiliense isolates that were randomly selected, including at least one isolate from each hospital where confirmed cases were detected, belonged to a single clone, as indicated by the analysis of pulsed-field gel electrophoresis (PFGE) patterns. They also had the same PFGE pattern as that previously observed in two outbreaks that occurred in other Brazilian cities; we designated this clone BRA100. All five BRA100 M. massiliense isolates tested presented consistent tolerance to 2% glutaraldehyde. This is the largest epidemic of postsurgical infections caused by RGM reported in the literature to date in Brazil.Outbreaks, pseudooutbreaks, and cases of health-care-associated infections caused by rapidly growing mycobacteria (RGM) have been reported since the first case was described in 1938 (13). In virtually all nosocomial infections caused by this group of microorganisms, there were failings in the sterilization processes of solutions, surgical instruments, or medical devices (13,14,45). Recent publications indicate an increasing number of infections secondary to breast augmentation and video-assisted surgeries (7,9,19,23,25,(40)(41)(42)(43).The growing number of cases and reports may be due, at least in part, to the well-known tolerance to alkaline glutaraldehyde among Mycobacterium chelonae-Mycobacterium abscessus group isolates and to the low susceptibility to high-level disinfectants (20,22,39).Outbreaks of RGM infections unrelated to medical procedures also can occur and usually are associated with exposure to recreational water containing a large number of bacteria and inadequate chlorination (15,44), highlighting the ubiquity of these organisms in the environment. In fact, RGM have been recovered from many different environmental sources, including soil and water distribution systems (8,45). RGM are considered opportunistic pathogens and can cause chronic lung disease, particularly the species included in the M. chelonae-M. abscessus group (8, 46)...

Three clinical strains (Escherichia coli Rio-6, E. coli Rio-7, and Enterobacter cloacae Rio-9) collected in 1996 and 1999 from hospitals in Rio de Janeiro (Brazil) were resistant to broad-spectrum cephalosporins and gave a positive double-disk synergy test. Two bla CTX-M genes encoding ␤-lactamases of pl 7.9 and 8.2 were implicated in this resistance: the bla CTX-M-9 gene observed in E. coli Rio-7 and E. cloacae Rio-9 and a novel CTX-Mencoding gene, designated bla CTX

To estimate the diversity of extended-spectrum ␤-lactamases in Brazil, 18 strains from different species of the family Enterobacteriaceae exhibiting a positive double-disk synergy test were collected by a clinical laboratory from several hospitals in Rio de Janeiro, Brazil, in 1996 and 1997. Four strains (Proteus mirabilis, Enterobacter cloacae, Enterobacter aerogenes, and Citrobacter amalonaticus) hybridized with a 550-bp CTX-M probe. The P. mirabilis strain produced a CTX-M-2 enzyme. The E. cloacae, E. aerogenes, and C. amalonaticus isolates harbored a bla gene which was identified by cloning and sequencing as a bla CTX-M gene. E. coli HB101 transconjugants and the E. coli DH5␣ transformant harboring a recombinant plasmid produced a CTX-M ␤-lactamase with an isoelectric point of 7.6 conferring a resistance phenotype characterized by a higher level of resistance to cefotaxime than to ceftazidime, as observed with the other CTX-M enzymes. The deduced protein sequence showed a novel Ambler class A CTX-M enzyme, named CTX-M-8, which had 83 to 88% identity with the previously described CTX-M enzymes. The phylogenic study of the CTX-M family including CTX-M-8 revealed four CTX-M types, CTX-M-8 being the first member of a new phylum of CTX-M enzymes. The evolutionary distances between the four types of CTX-M were large, suggesting that the four clusters branched off early from a distant unknown enzyme and that intermediate enzymes probably existed.

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Multidrug-resistant Pseudomonas aeruginosa nosocomial infections are increasingly recognized worldwide. The existence of metallo-␤-lactamase-and extended-spectrum ␤-lactamase-producing isolates exhibiting resistance to most ␤-lactam antimicrobial agents greatly complicates the clinical management of patients infected with such isolates. Since 1998, P. aeruginosa isolates resistant to all commercially available antimicrobial agents have been detected at a university-affiliated public hospital in Rio de Janeiro, Brazil. The present study was designed to characterize the antimicrobial resistance profiles and the genetic diversity of the P. aeruginosa strains isolated at this hospital and four private hospitals in Rio de Janeiro. Between April 1999 and March 2000, 200 consecutive isolates were obtained and analyzed for antimicrobial resistance. The genetic diversity of a selected number of them was evaluated by pulsed-field gel electrophoresis and PCR with the ERIC-2 primer. A predominant genotype, designated genotype A, was identified among isolates from four of the five hospitals evaluated. Eighty-four ceftazidime-resistant isolates were evaluated for metallo-␤-lactamase production, which was detected in 20 (91%) of 22 genotype A isolates and 11 (18%) of 62 isolates belonging to other genotypes (P < 0.05). Two metallo-␤-lactamase-producing genotype A isolates also produced an extended-spectrum ␤-lactamase. The occurrence of multidrug-resistant P. aeruginosa strains belonging to a unique genotype in different hospitals in Rio de Janeiro underscores the importance of the contribution of a single clone to the increase in the incidence of multidrug-resistant P. aeruginosa nosocomial infections.

Serratia marcescens Rio-5, one of 18 extended-spectrum ␤-lactamase (ESBL)-producing strains isolated in several hospitals in Rio de Janeiro (Brazil) in 1996 and 1997, exhibited a high level of resistance to aztreonam (MIC, 512 g/ml) and a distinctly higher level of resistance to cefotaxime (MIC, 64 g/ml) than to ceftazidime (MIC, 8 g/ml). The strain produced a plasmid-encoded ESBL with a pI of 7.5 whose bla gene was not related to those of other plasmid-mediated Ambler class A ESBLs. Cloning and sequencing revealed a bla gene encoding a novel class A ␤-lactamase in functional group 2be, designated BES-1 (Brazil extended-spectrum ␤-lactamase). This enzyme had 51% identity with chromosomal class A penicillinase of Yersinia enterocolitica Y56, which was the most closely related enzyme and 47 to 48% identity with CTX-M-type ␤-lactamases, which were the most closely related ESBLs. In common with CTX-M enzymes, BES-1 exhibited high cefotaxime-hydrolyzing activity (k cat , 425 s ؊1 ). However, BES-1 differed from CTX-M enzymes by its significant ceftazidimehydrolyzing activity (k cat , 25 s Shortly after the introduction of extended-spectrum ␤-lactams such as cefotaxime, aztreonam, and ceftazidime, extended-spectrum ␤-lactamases (ESBLs) were characterized for members of the family Enterobacteriaceae, firstly in Europe (23, 47) and then worldwide. These enzymes hydrolyze extended-spectrum cephalosporins and aztreonam to varying extents but usually neither cephamycins (cefoxitin and moxalactam) nor carbapenems (imipenem and meropenem). A common feature of these enzymes is inhibition of their activity by clavulanic acid. According to the structural classification of Ambler et al. (1) and the latest functional scheme of Bush et al. (11), these ESBLs are generally class A enzymes of the 2be group, which arise as the result of a few amino acid substitutions from the common plasmid-mediated TEM and SHV-1 ␤-lactamases.Since the first report of MEN-1 (CTX-M-1) at the beginning of the 1990s (3), non-TEM, non-SHV, class A ESBLs have been observed for strains of the family Enterobacteriaceae and in Pseudomonas aeruginosa. Except for the ESBL SFO-1, which is closely related to the chromosomal enzyme of Serratia fonticola (28), these ESBLs, especially the enzyme GES-1 (39), are distantly related not only to one another but also to chromosome-borne enzymes. However, two groups can be considered; on the one hand, the ESBLs of the growing family CTX-M (7), which cluster with the class A chromosomally encoded ␤-lactamases of Proteus vulgaris (36), S. fonticola (35), Citrobacter diversus (37), Klebsiella oxytoca (2), Burkholderia cepacia (52), and Yersinia enterocolitica (45), and on the other hand, the ESBLs of the PER type (5, 32), TLA-1 (46), and VEB-1 (40), which cluster with Bacteroides class A chromosomal ␤-lactamases (42, 48) and the ␤-lactamase CME-1 of Chryseobacterium (Flavobacterium) meningosepticum (43).To estimate the diversity of ESBLs in Brazil, clinical strains that exhibited ESBL phenotypes in different species were co...

During the last 30 years there has been a dissemination of plasmid-mediated β-lactamases in Enterobacteriaceae in Brazil. Extended spectrum β-lactamases (ESBL) are widely disseminated in the hospital setting and are detected in a lower frequency in the community setting. Cefotaximases are the most frequently detected ESBL type and Klebsiella pneumoniae is the predominant species among ESBL producers. Klebsiella pneumoniae carbapenemase-producing Enterobacteriaceae became widely disseminated in Brazil during the last decade and KPC production is currently the most frequent resistance mechanism (96.2%) in carbapenem resistant K. pneumoniae. To date KPC-2 is the only variant reported in Brazil. Polymyxin B resistance in KPC-2-producing K. pneumoniae has come to an alarming rate of 27.1% in 2015 in São Paulo, the largest city in Brazil. New Delhi metallo-β-lactamase was detected in Brazil in 2013, has been reported in different Brazilian states but are not widely disseminated. Antimicrobial resistance in Enterobacteriaceae in Brazil is a very serious problem that needs urgent actions which includes both more strict adherence to infection control measures and more judicious use of antimicrobials.