Molecular Epidemiology of blaKPC-Encoding Klebsiella pneumoniae Isolated from Public Hospitals in Midwest of Brazil.

This study was conducted to determine the molecular epidemiology of blaKPC-encoding Klebsiella pneumoniae recovered from three public hospitals in Brazil. Molecular investigation of blaOXA-48, blaKPC, blaNDM, blaCTX-M, blaSHV, blaTEM, blaIMP, and blaVIM resistance genes was performed in 99 K. pneumoniae isolates from inpatients of intensive care units. Antimicrobial susceptibility was determined with a Vitek-2 System, except for polymyxin B, which was evaluated by the microbroth dilution test. Clonal relatedness was established by pulsed-field gel electrophoresis and multilocus sequence typing. Screening resistance genes showed that K. pneumoniae isolates carried the blaKPC (88.9%), blaSHV (73.5%), blaTEM (72.2%), and blaCTX-M (43.9%) genes. The most frequent sequence types (STs) were ST273, ST11, ST 1298, ST13, ST2687, and ST37. We report new STs in K. pneumoniae that have not been detected previously in Brazil. K. pneumoniae belonging to the same clone is present in different hospitals in the same region, showing the spread of multidrug-resistant K. pneumoniae.

Post-neurosurgical meningitis caused by KPC-producing Klebsiella pneumoniae: report of two cases.

Nosocomial bacterial infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) is associated with high mortality in neurosurgical patients. There are few reports in the literature on meningitis caused by CRKP. We report two cases of CRKP meningitis after neurosurgery. The K. pneumoniae identification and antimicrobial susceptibility testing were performed using the Vitek Compact System. Minimum inhibitory concentrations of polymyxin B were determined using the broth microdilution method. Molecular typing of K. pneumoniae isolates was investigated using multilocus sequence typing. Antimicrobial susceptibility testing showed that the K. pneumoniae isolates were multidrug resistant and co-produced extended-spectrum ß-lactamases and KPC enzymes. The patients were treated with intrathecal polymyxin. Genetic polymorphism analyses revealed two different K. pneumoniae clones (ST1298 and ST2687), which were observed for the first time in CRKP infections. We recommend intravenous administration of intrathecal polymyxin for treating meningitis caused by multidrug-resistant K. pneumoniae .

Non-clonal occurrence of pmrB mutations associated with polymyxin resistance in carbapenem-resistant Klebsiella pneumoniae in Brazil.

BACKGROUND: Polymyxins are currently used as a "last-line" treatment for multidrug-resistant Gram-negative infections. OBJECTIVES: To identify the major mechanisms of resistance to polymyxin and compare the genetic similarity between multi-drug resistant Klebsiella pneumoniae strains recovered from inpatients of public hospitals in the Mid-West of Brazil. METHODS: 97 carbapenems non-susceptible K. pneumoniae were studied. ß-lactamases (bla OXA-48, bla KPC, bla NDM, bla CTX-M, bla SHV, bla TEM, bla IMP, bla VIM) and mcr-1 to mcr-5 genes were investigated by polymerase chain reaction (PCR). Mutations in chromosomal genes (pmrA, pmrB, phoP, phoQ, and mgrB) were screened by PCR and DNA sequencing. Clonal relatedness was established by using pulsed-field gel electrophoresis and multilocus sequence typing. FINDINGS: K. pneumoniae isolates harbored bla KPC (93.3%), bla SHV (86.6%), bla TEM (80.0%), bla CTX-M (60%) genes. Of 15 K. pneumoniae resistant to polymyxin B the authors identified deleterious mutations in pmrB gene, mainly in T157P. None K. pneumoniae presented mcr gene variants. Genetic polymorphism analyses revealed 12 different pulsotypes. MAIN CONCLUSIONS: Deleterious mutations in pmrB gene is the main chromosomal target for induction of polymyxin resistance in carbapenem-resistant K. pneumoniae in public hospitals in the Mid-West of Brazil.

Melioidosis, an emerging infectious disease in the Midwest Brazil: A case report.

RATIONALE: Melioidosis is an emerging infectious disease in Brazil and caused by Burkholderia pseudomallei, with high morbidity and mortality rates. A total of 28 melioidosis cases were reported in Brazil until 2015. The majority of melioidosis cases were reported in the Northwest region of Brazil and such cases were not previously detected in the Midwest region of Brazil. PATIENT CONCERNS: A 42-year-old man was admitted with a non-productive cough, dyspnea, myalgia, diffuse abdominal pain. Pulmonary auscultation revealed a vesicular murmur, snoring sounds, and the presence of basal crackling rales in the left hemithorax. The patient evolved with several respiratory failures and he was diagnosed as the first case of community-acquired pneumonia with sepsis caused by B pseudomallei in Mato Grosso do Sul, Midwest state of Brazil. DIAGNOSIS: The cell isolates were subjected to 16S rRNA gene sequencing to confirm the bacterial species. INTERVENTIONS: Administration of trimethoprim/sulfamethoxazole and meropenem stabilized the clinical condition of the patient. Subsequently upon discharge, the patient was also treated with trimethoprim/sulfametothoxazole for a year. OUTCOME: We reported the first case of community-acquired pneumonia with sepsis caused by B pseudomallei in Mato Grosso do Sul, Midwest state of Brazil and the patient survived. LESSONS: The emergence of melioidosis in the Midwest region is being neglected and underestimated and melioidosis must be considered of the differential diagnosis in community infections.

Non-clonal occurrence of pmrB mutations associated with polymyxin resistance in carbapenem-resistant Klebsiella pneumoniae in Brazil

BACKGROUND Polymyxins are currently used as a "last-line" treatment for multidrug-resistant Gram-negative infections. OBJECTIVES To identify the major mechanisms of resistance to polymyxin and compare the genetic similarity between multi-drug resistant Klebsiella pneumoniae strains recovered from inpatients of public hospitals in the Mid-West of Brazil. METHODS 97 carbapenems non-susceptible K. pneumoniae were studied. β-lactamases (bla OXA-48, bla KPC, bla NDM, bla CTX-M, bla SHV, bla TEM, bla IMP, bla VIM) and mcr-1 to mcr-5 genes were investigated by polymerase chain reaction (PCR). Mutations in chromosomal genes (pmrA, pmrB, phoP, phoQ, and mgrB) were screened by PCR and DNA sequencing. Clonal relatedness was established by using pulsed-field gel electrophoresis and multilocus sequence typing. FINDINGS K. pneumoniae isolates harbored bla KPC (93.3%), bla SHV (86.6%), bla TEM (80.0%), bla CTX-M (60%) genes. Of 15 K. pneumoniae resistant to polymyxin B the authors identified deleterious mutations in pmrB gene, mainly in T157P. None K. pneumoniae presented mcr gene variants. Genetic polymorphism analyses revealed 12 different pulsotypes. MAIN CONCLUSIONS Deleterious mutations in pmrB gene is the main chromosomal target for induction of polymyxin resistance in carbapenem-resistant K. pneumoniae in public hospitals in the Mid-West of Brazil.

KPC-2-producing Klebsiella pneumoniae in a hospital in the Midwest region of Brazil.

The emergence of ß-lactamase-producing Enterobacteriaceae in the last few decades has become major challenge faced by hospitals. In this study, isolates of Klebsiella pneumoniae carbapenemase-2 (KPC-2)-producing K. pneumoniae from a tertiary hospital in Mato Grosso do Sul, Brazil, were characterized. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF; Bruker Daltonics, Germany) mass spectrometry. The minimum inhibitory concentrations of carbapenems were determined using the agar dilution method as recommended by the Clinical Laboratory Standards Institute guidelines. Carbapenemase production was detected using the modified Hodge test (MHT) and polymerase chain reaction (PCR), followed by DNA sequencing. Of 360 (12.2%) K. pneumoniae isolates obtained between May 2009 and May 2010, 44 (12.2%) were carbapenem nonsusceptible. Of these 44 isolates, thirty-six K. pneumoniae isolates that were positive by MHT and PCR carried the bla KPC-2 gene. Thus, KPC-2producing Klebsiella pneumoniae has been present in a Brazilian hospital located in the Midwest region since at least 2009.

KPC-2-producing Klebsiella pneumoniae in a hospital in the Midwest region of Brazil

The emergence of β-lactamase-producing Enterobacteriaceae in the last few decades has become major challenge faced by hospitals. In this study, isolates of Klebsiella pneumoniae carbapenemase-2 (KPC-2)-producing K. pneumoniae from a tertiary hospital in Mato Grosso do Sul, Brazil, were characterized. Bacterial identification was performed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF; Bruker Daltonics, Germany) mass spectrometry. The minimum inhibitory concentrations of carbapenems were determined using the agar dilution method as recommended by the Clinical Laboratory Standards Institute guidelines. Carbapenemase production was detected using the modified Hodge test (MHT) and polymerase chain reaction (PCR), followed by DNA sequencing. Of 360 (12.2%) K. pneumoniae isolates obtained between May 2009 and May 2010, 44 (12.2%) were carbapenem nonsusceptible. Of these 44 isolates, thirty-six K. pneumoniae isolates that were positive by MHT and PCR carried the blaKPC-2 gene. Thus, KPC-2producing Klebsiella pneumoniae has been present in a Brazilian hospital located in the Midwest region since at least 2009.

Metallo-ß-lactamase and genetic diversity of Pseudomonas aeruginosa in intensive care units in Campo Grande, MS, Brazil.

Infection by Pseudomonas aeruginosa has spread worldwide, with limited options for treatment. The purpose of this study was to investigate metallo-ß-lactamase-producing P. aeruginosa strains and compare their genetic profile using samples collected from patients in intensive care units. Forty P. aeruginosa strains were isolated from two public hospitals in Campo Grande, Mato Grosso do Sul State, from January 1st, 2007 to June 31st, 2008. Profiles of antimicrobial susceptibility were determined using the agar diffusion method. Metallo-ß-lactamase was investigated using the double-disk diffusion test and PCR. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE). Respiratory and urinary tracts were the most common isolation sites. Of the 40 samples tested, 72.5% (29/40) were resistant to ceftazidime and 92.5% (37/40) to imipenem, whereas 65% (26/40) were resistant to both antimicrobials. Fifteen pan-resistant samples were found. Five percent (2/40) of samples were positive for metallo-ß-lactamase on the phenotype test. No metallo-ß-lactamase subtype was detected by PCR. Macrorestriction analysis revealed 14 distinct genetic patterns. Based on the superior accuracy of PCR, it can be inferred that P. aeruginosa isolates from the investigated hospitals have alternative mechanisms of carbapenem resistance. The results also suggest clonal spread of P. aeruginosa between the studied hospitals.

Metallo-β-lactamase and genetic diversity of Pseudomonas aeruginosa in intensive care units in Campo Grande, MS, Brazil

Infection by Pseudomonas aeruginosa has spread worldwide, with limited options for treatment. The purpose of this study was to investigate metallo-β-lactamase-producing P. aeruginosa strains and compare their genetic profile using samples collected from patients in intensive care units. Forty P. aeruginosa strains were isolated from two public hospitals in Campo Grande, Mato Grosso do Sul State, from January 1st, 2007 to June 31st, 2008. Profiles of antimicrobial susceptibility were determined using the agar diffusion method. Metallo-β-lactamase was investigated using the double-disk diffusion test and PCR. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE). Respiratory and urinary tracts were the most common isolation sites. Of the 40 samples tested, 72.5 percent (29/40) were resistant to ceftazidime and 92.5 percent (37/40) to imipenem, whereas 65 percent (26/40) were resistant to both antimicrobials. Fifteen pan-resistant samples were found. Five percent (2/40) of samples were positive for metallo-β-lactamase on the phenotype test. No metallo-β-lactamase subtype was detected by PCR. Macrorestriction analysis revealed 14 distinct genetic patterns. Based on the superior accuracy of PCR, it can be inferred that P. aeruginosa isolates from the investigated hospitals have alternative mechanisms of carbapenem resistance. The results also suggest clonal spread of P. aeruginosa between the studied hospitals.