ABSTRACT
Water-filled sinkholes known locally as cenotes, found on the Yucatán Peninsula, have remarkable biodiversity. The primary objective of this study was to explore the biotechnological potential of Gram-positive cultivable bacteria obtained from sediment samples collected at the coastal cenote Pol-Ac in Yucatán, Mexico. Specifically, the investigation aimed to assess production of hydrolytic enzymes and antimicrobial compounds. 16 S rRNA gene sequencing led to the identification of 49 Gram-positive bacterial isolates belonging to the phyla Bacillota (n = 29) and Actinomycetota (n = 20) divided into the common genera Bacillus and Streptomyces, as well as the genera Virgibacillus, Halobacillus, Metabacillus, Solibacillus, Neobacillus, Rossellomorea, Nocardiopsis and Corynebacterium. With growth at 55ºC, 21 of the 49 strains were classified as moderately thermotolerant. All strains were classified as halotolerant and 24 were dependent on marine water for growth. Screening for six extracellular hydrolytic enzymes revealed gelatinase, amylase, lipase, cellulase, protease and chitinase activities in 93.9%, 67.3%, 63.3%, 59.2%, 59.2% and 38.8%, of isolated strains, respectively. The genes for polyketide synthases type I, were detected in 24 of the strains. Of 18 strains that achieved > 25% inhibition of growth in the bacterial pathogen Staphylococcus aureus ATCC 6538, 4 also inhibited growth in Escherichia coli ATCC 35,218. Isolates Streptomyces sp. NCA_378 and Bacillus sp. NCA_374 demonstrated 50-75% growth inhibition against at least one of the two pathogens tested, along with significant enzymatic activity across all six extracellular enzymes. This is the first comprehensive report on the biotechnological potential of Gram-positive bacteria isolated from sediments in the cenotes of the Yucatán Peninsula.
Subject(s)
Biodiversity , Geologic Sediments , Gram-Positive Bacteria , RNA, Ribosomal, 16S , Geologic Sediments/microbiology , Mexico , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacteria/genetics , Gram-Positive Bacteria/classification , RNA, Ribosomal, 16S/genetics , Bioprospecting , Phylogeny , Anti-Bacterial Agents/pharmacology , Seawater/microbiologyABSTRACT
In this present study, 63 different 5-[4-methyl-2-(pyridin-3/4-yl)thiazole-5-yl]-4-substituted-3-substituted benzylthio-4H-1,2,4-triazole derivatives were synthesized, and evaluated for their in vitro antimicrobial activity against various human pathogenic microorganisms and antioxidant activity. The derivatives were synthesized in a multi-step synthesis procedure including triazole and thiazole ring closure reactions, respectively. The synthesized derivatives (A1-24; B1-39) were screened for their antibacterial, antifungal, and antioxidant activities compared to standard agents. The derivatives possessing 3-pyridyl moiety particularly exhibited relatively high antibacterial activity (MIC= < 3.09-500 µg/mL) against Gram-positive bacteria, and compounds possessing 4-pyridyl moiety showed remarkable antioxidant activity
Subject(s)
Pyridines/analysis , Thiazoles/analysis , Triazoles/analysis , Methods , Antioxidants , In Vitro Techniques/methods , Gram-Positive Bacteria/classificationABSTRACT
Biosensors are pre-prepared diagnostic devices composed of at least one biological probe. These devices are envisaged for the practical identification of specific targets of microbiological interest. In recent years, the use of narrow-specific probes such as lectins has been proven to distinguish bacteria and glycoproteins based on their superficial glycomic pattern. For instance, Concanavalin A is a carbohydrate-binding lectin indicated as a narrow-specific biological probe for Gram-negative bacteria. As a drawback, Gram-positive bacteria are frequently overlooked from lectin-based biosensing studies because their identification results in low resolution and overlapped signals. In this work, the authors explore the effect that platform nanostructuration has over the electrochemical response of ConA-based platforms constructed for bacterial detection; one is formed of chitosan-capped magnetic nanoparticles, and another is composed of gold nanoparticle-decorated magnetic nanoparticles. The biosensing platforms were characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) as a function of bacterial concentration. Our results show that probe-target interaction causes variations in the electrical responses of nanostructured transducers. Moreover, the association of gold nanoparticles to magnetic nanoparticles resulted in an electrical enhancement capable of overcoming low resolution and overlapping Gram-positive identification. Both platforms attained a limit of detection of 10 ° CFU mL-1, which is useful for water analyses and sanitation concerns, where low CFU mL-1 are always expected. Although both platforms were able to detect Gram-negative bacteria, Gram-positives were only correctly differentiated by the gold nanoparticle-decorated magnetic nanoparticles, thus demonstrating the positive influence of hierarchically nanostructured platforms.
Subject(s)
Biosensing Techniques , Concanavalin A , Gram-Positive Bacteria , Biosensing Techniques/methods , Concanavalin A/pharmacology , Gold , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/drug effects , Metal Nanoparticles , TransducersABSTRACT
In this Research Communication we evaluate the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify 380 bacteria isolated from cases of bovine mastitis in Brazil. MALDI-TOF MS identifications were compared to previous identifications by biochemical tests and 16S rRNA sequencing. MALDI-TOF MS achieved a typeability of 95.5%. The accuracy of MALDI-TOF MS for the identification of Staphylococcus isolates was 93.2%. The agreement between MALDI-TOF MS and biochemical identification of Streptococcus agalactiae was 96%, however, the agreement between these techniques for identifying other catalase-negative, Gram-positive cocci was lower. Agreement in identifying Gram-negative bacteria at the genus level was 90.5%. Our findings corroborate that MALDI-TOF MS is an accurate, rapid and simple technique for identifying bovine mastitis pathogens. The availability of this methodology in some research institutions would represent a significant step toward increasing the diagnosis and epidemiological studies of bovine mastitis and other animal infectious diseases in Brazil.
Subject(s)
Mastitis, Bovine/microbiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/veterinary , Animals , Brazil , Cattle , Female , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/genetics , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/genetics , Milk/microbiology , RNA, Ribosomal, 16S/genetics , Sensitivity and Specificity , Sequence Analysis, RNA , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Staphylococcus/genetics , Streptococcus agalactiae/geneticsABSTRACT
INTRODUCTION: The mother plays a fundamental role in the constitution and regulation of her child's healthy microbiota, however, preterm newborns are separated from their mothers soon after birth and transferred to Neonatal Intensive Care Units, being exposed the constant risk for the development of multidrug-resistant microorganisms' infections. The aim of this study was to explore the multidrug-resistant microorganism colonization of hospitalized babies and their mothers in the neonatal unit context. METHODOLOGY: A prospective case study conducted with hospitalized babies and their mothers in the Neonatal Unit at a university hospital. The sample was composed of 433 binomials (mother-child). Colonization culture samples were taken at the moment of the baby's discharge, via two swabs in the oral, nasal, axillary, inguinal, and rectal regions. RESULTS: The colonization incidence among the binomials, 30 (6.9%) were both colonized by multi-resistant microorganisms. Mothers of colonized babies (24.4%) demonstrated a higher chance of colonization in comparison to mothers of non-colonized babies (11.9%) (p = 0.002). Relationships were drawn between baby colonization and prematurity, extremely low birth weight, and non-exclusive maternal breastfeeding (p<0.05). ESBL-producing Gram-negative microorganisms were more frequent in the cultures of the binomials, with 35.9% of the babies colonized with Klebsiella spp. ESBL and 42.0% of the mothers with Escherichia coli ESBL. Furthermore, 50% of the binomials were colonized with E. coli ESBL. CONCLUSION: The prematurity, extremely low birth weight, and non-exclusive breastfeeding at hospital discharge were associated with baby colonization by multidrug-resistant microorganism. Furthermore, mothers of colonized children presented higher chances of colonization.
Subject(s)
Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Premature Birth/microbiology , Adolescent , Adult , Bacterial Infections/microbiology , Drug Resistance, Multiple, Bacterial , Escherichia coli/drug effects , Escherichia coli/metabolism , Female , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Hospitalization , Hospitals, University , Humans , Infant, Newborn , Infant, Premature , Intensive Care Units, Neonatal , Klebsiella/drug effects , Klebsiella/metabolism , Male , Microbial Sensitivity Tests , Mother-Child Relations , Mothers , Patient Discharge , Prospective Studies , Young Adult , beta-Lactamases/metabolismABSTRACT
INTRODUCTION: The present study aimed to determine the incidence of health care-associated infections (HCAIs) and identify the main resistant microorganisms in intensive care unit (ICU) patients in a Brazilian university hospital. METHODS: A retrospective cohort study was conducted in a Brazilian teaching hospital between 2012 and 2014. RESULTS: Overall, 81.2% of the infections were acquired in the ICU. The most common resistant pathogenic phenotypes in all-site and bloodstream infections were oxacillin-resistant coagulase-negative staphylococci and carbapenem-resistant Acinetobacter spp. (89.9% and 87.4%; 80.6% and 70.0%), respectively. CONCLUSIONS: There is an urgent need to focus on HCAIs in ICUs in Brazil.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteremia/microbiology , Drug Resistance, Bacterial , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Adult , Bacteremia/mortality , Female , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Hospital Mortality , Humans , Incidence , Intensive Care Units , Male , Microbial Sensitivity Tests , Middle Aged , Retrospective Studies , Time FactorsABSTRACT
Bacteriocins are ribosomally synthesized peptides with antibacterial activity against food-borne pathogenic bacteria that cause spoilage, possessing important potential for use as a natural preservative in the food industry. The novel bacteriocin BM1300 produced by Lactobacillus crustorum MN047 was identified after purification in this study. It displayed broad-spectrum antibacterial activity against some selected Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration (MIC) values of BM1300 against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 were 13.4 µg/mL and 6.7 µg/mL, respectively. Moreover, BM1300 showed excellent thermal (between 60 and 120 °C), pH (2-11), and chemical (Tween-40, Tween-80, Triton X-100, and EDTA) stabilities. Time-kill curves revealed that BM1300 exhibited bactericidal activity against S. aureus and E. coli. The scanning and transmission electron microscopy indicated that BM1300 acted by disrupting the cell membrane integrity and increasing cell membrane permeabilization of indicator bacteria. The disruption of cell membrane integrity caused by BM1300 was further demonstrated by the uptake of propidium iodide (PI) and the release of intracellular lactate dehydrogenase (LDH) and nucleic acid and proteins. Moreover, BM1300 affected cell cycle distribution to exert antibacterial activity collaboratively. Meanwhile, BM1300 inhibited the growth of S. aureus and E. coli of beef meat and improved the microbiological quality of beef meat. These findings place BM1300 as a potential biopreservative in the food industry.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteriocins/pharmacology , Lactobacillus/chemistry , Animals , Anti-Bacterial Agents/classification , Erythrocytes/drug effects , Escherichia coli/genetics , Escherichia coli/metabolism , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/drug effects , Hemolysis , Mice , Microbial Sensitivity TestsABSTRACT
Atrazine is a triazine herbicide that is widely used to control broadleaf weeds. Its widespread use over the last 50 years has led to the potential contamination of soils, groundwater, rivers, and lakes. Its main route of complete degradation is via biological means, which is carried out by soil microbiota using a 6-step pathway. The aim of the present study was to investigate whether application of atrazine to soil changes the soil bacterial community. We used 16S rRNA gene sequencing and qPCR to elucidate the microbial community structure and assess the abundance of the atrazine degradation genes atzA, atzD, and trzN in a Brazilian soil. The results obtained showed that the relative abundance of atzA and trzN, encoding triazine-initiating metabolism in Gram-negative and -positive bacteria, respectively, increased in soil during the first weeks following the application of atrazine. In contrast, the abundance of atzD, encoding cyanuric acid amidohydrolase-the fourth step in the pathway-was not related to the atrazine treatment. Moreover, the overall soil bacterial community showed no significant changes after the application of atrazine. Despite this, we observed increases in the relative abundance of bacterial families in the 4th and 8th weeks following the atrazine treatment, which may have been related to higher copy numbers of atzA and trzN, in part due to the release of nitrogen from the herbicide. The present results revealed that while the application of atrazine may temporarily increase the quantities of the atzA and trzN genes in a Brazilian Red Latosol soil, it does not lead to significant and long-term changes in the bacterial community structure.
Subject(s)
Atrazine/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Herbicides/pharmacology , Microbiota/drug effects , Soil Microbiology , Biodegradation, Environmental , Brazil , Genes, Bacterial , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , RNA, Ribosomal, 16S/genetics , Soil/chemistry , Soil Pollutants/pharmacology , Tropical ClimateABSTRACT
The aim of this study was to determine the spontaneous decolonization period and characteristics in a prospective cohort of newborns colonized by multidrug-resistant organisms, after their discharge from the neonatal intensive care unit. Multidrug resistance is defined as bacterial non-susceptibility to ≥ 1 agent of ≥ 3 antimicrobial categories. In total, 618 newborns were included in the study, of which 173 (28.0%) presented a positive culture for multidrug-resistant microorganisms, and of these, 52 (30.1%) were followed up in this study. The most frequent intrinsic factors were be born by cesarean section (86.5%), prematurity (84.6%), and very low birth weight (76.9%). The extrinsic factors were having remained hospitalized for an average of 27 days, during which 67.3% were submitted to invasive procedures and 88.5% received antimicrobials. The intrinsic and extrinsic factors of newborns were not associated to a decolonization period longer or shorter than 3 months, which was the average period of decolonization found in the present study. From the totality of colonization cultures sampled at hospital discharge, the Gram-negative Extended Spectrum ß-lactamase producing bacteria were the most common, with 28.9% of babies colonized by Klebsiella spp. The median period of decolonization by multidrug-resistant microorganisms in the newborns population after hospital discharge was 3 months, but was highly dependent on the microbial species, and this period was not associated to any intrinsic and extrinsic factors of the newborn.
Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Cohort Studies , Female , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Humans , Infant, Newborn , Intensive Care Units, Neonatal , Male , Microbial Sensitivity Tests , Patient Discharge , Prospective Studies , Risk FactorsABSTRACT
Abstract INTRODUCTION: The present study aimed to determine the incidence of health care-associated infections (HCAIs) and identify the main resistant microorganisms in intensive care unit (ICU) patients in a Brazilian university hospital. METHODS: A retrospective cohort study was conducted in a Brazilian teaching hospital between 2012 and 2014. RESULTS: Overall, 81.2% of the infections were acquired in the ICU. The most common resistant pathogenic phenotypes in all-site and bloodstream infections were oxacillin-resistant coagulase-negative staphylococci and carbapenem-resistant Acinetobacter spp. (89.9% and 87.4%; 80.6% and 70.0%), respectively. CONCLUSIONS: There is an urgent need to focus on HCAIs in ICUs in Brazil.
Subject(s)
Humans , Male , Female , Adult , Bacteremia/microbiology , Drug Resistance, Bacterial , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Time Factors , Microbial Sensitivity Tests , Incidence , Retrospective Studies , Hospital Mortality , Bacteremia/mortality , Gram-Negative Bacteria/isolation & purification , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacteria/classification , Intensive Care Units , Middle AgedABSTRACT
OBJECTIVE: to evaluate the potential contamination of enzymatic detergent from its reuse and to identify the microbiological profile in the solution used to clean gastrointestinal endoscopic devices. METHOD: cross-sectional study based on microbiological analysis of 76 aliquots of 19 different enzymatic detergent solutions used to clean endoscopic devices. The aliquots were homogenized, subjected to Millipore® 0.45 µm membrane filtration and the presumptive identification of microorganisms was performed by biochemical-physiological methods according to previously established specific bacterial groups that are of clinical and epidemiological relevance. RESULTS: the mean values, as well as the standard deviation and the median, of the enzymatic detergent microbial load increased as the solution was reused. There was a significant difference between the means of after first use and after fifth reuse. A total of 97 microorganisms were identified, with predominance of the coagulase-negative Staphylococcus, Pseudomonas spp., Klebsiella spp., Enterobacter spp. genus, and Escherichia coli species. CONCLUSION: the reuse of the enzymatic detergent solution is a risk to the safe processing of endoscopic devices, evidenced by its contamination with pathogenic potential microorganisms, since the enzymatic detergent has no bactericidal property and can contribute as an important source for outbreaks in patients under such procedures.
Subject(s)
Detergents/adverse effects , Equipment Contamination , Gastroscopes/adverse effects , Gastroscopes/microbiology , Bacterial Load , Cross-Sectional Studies , Detergents/pharmacology , Disease Transmission, Infectious , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Humans , Infection ControlABSTRACT
In this study, the antimicrobial, antioxidant and antitumor activity of ethanol extracts obtained from Phlomis russeliana (Sims.) Lag. ex Benth. (Lamiaceae) were evaluated. Disc diffusion and microdilution methods were used to test the extracts for antimicrobial activity against seven bacteria strains (Bacillus cereus ATCC 7064, Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538P, Escherichia coli ATCC 10538, Proteus vulgaris ATCC 6899, Salmonella typhimurium CCM 5445 and Pseudomonas aeruginosa ATCC 27853) and four yeast strains (Kluyveromyces fragilis ATCC 8608, Rhodotorula rubra ATCC 70403, Debaryomyces hansenii DSM 70238 and Candida albicans ATCC 10239). Notably, they were more effective against the yeast strains than the bacterial strains. Of the yeast cultures, D. hanseii was among the most susceptible, having an inhibition zone of 16.2 mm with minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of 64(128)µg/ml, respectively. For cytotoxic determination, Caco-2 cells were cultured as per ATCC protocol, and were treated with log concentrations (5-80 mg/ml) of P. russeliana. The potency of cell growth inhibition for each extract was expressed as an IC50 value. Moreover, oxidant capacity was evaluated via TOC assay. This product induced antiproliferative activity of 31.33% at 40 mg/ml and 20.96% at 80 mg/ml, without toxic effects on cells, although the oxidant capacity was decreased to 27.06 ± 0.7 nm in the 80 mg/ml-applied group compared to 47.9 ± 1.8 nm in the untreated one. Advanced pharmacological studies are needed to further evaluate P. russeliana for distinctive features.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Candida albicans/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Phlomis/chemistry , Plant Extracts/pharmacology , Anti-Bacterial Agents/isolation & purification , Antioxidants/isolation & purification , Caco-2 Cells , Disk Diffusion Antimicrobial Tests , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Humans , TurkeyABSTRACT
Mass spectrometry has revolutionized the clinical microbiology field in America's and Europe's industrialized countries, for being a fast, reliable and inexpensive technique. Our study is based on the comparison of the performance of two commercial platforms, Microflex LT (Bruker Daltonics, Bremen, Germany) and Vitek MS (bioMérieux, Marcy l´Etoile, France) for the identification of unusual and hard-to-diagnose microorganisms in a Reference Laboratory in Argentina. During a four-month period (February-May 2018) the diagnostic efficiency and the concordance between both systems were assessed, and the results were compared with the polyphasic taxonomic identification of all isolates. The study included 265 isolates: 77 Gram-Negative Bacilli, 33 Gram-Positive Cocci, 40 Anaerobes, 35 Actinomycetales, 19 Fastidious Microorganisms and 61 Gram-Positive Bacilli. All procedures were practiced according to the manufacturer's recommendations in each case by duplicate, and strictly in parallel. Other relevant factors, such as the utility of the recommended extraction protocols, reagent stability and connectivity were also evaluated. Both systems correctly identified the majority of the isolates to species and complex level (82%, 217/265). Vitex MS achieved a higher number of correct species-level identifications between the gram-positive microorganisms; however, it presented greater difficulty in the identification of non-fermenting bacilli and a higher number of incorrect identifications when the profile of the microorganism was not represented in the commercial database. Both platforms showed an excellent performance on the identification of anaerobic bacteria and fastidious species. Both systems enabled the fast and reliable identification of most of the tested isolates and were shown to be very practical for the user.
Subject(s)
Gram-Negative Bacteria , Gram-Positive Bacteria , Mass Spectrometry , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/isolation & purification , Gram-Negative Bacteria/metabolism , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacteria/metabolism , HumansABSTRACT
Bloodstream infections (BSIs) are serious infections associated with high rates of morbidity and mortality. Every hour delay in initiation of an effective antibiotic increases mortality due to sepsis by 7%. Turnaround time (TAT) for conventional blood cultures takes 48h, forcing physicians to streamline therapy by exposing patients to broad-spectrum antimicrobials. Our objective was (1) to evaluate the accuracy and TAT of an optimized workflow combining direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and in-house real-time polymerase chain reaction (PCR) for bacterial identification and antimicrobial resistance profiling directly from positive blood bottles for diagnosing bloodstream infections and (2) to verify the effect of reporting results to medical staff. A total of 103 BSI episodes from 91 patients admitted to three hospitals in São Paulo, Brazil were included. TAT from molecular versus conventional methods was measured and compared. Our protocol showed an overall agreement of 93.5% for genus and 78.5% for species identification; 74.2% for methicillin resistance detection, 89.2% for extended-spectrum ß-lactamase profiling, 77.8% for metallo-ß-lactamase profiling, and 100% for carbapenemase profile and vancomycin-resistance detection when compared with conventional testing. TAT of molecular sample processing according to our protocol was 38h shorter than conventional methods. Antimicrobial interventions were possible in 27 BSI episodes. Antimicrobial discontinuation was achieved in 12 BSI episodes while escalation of therapy occurred in 15 episodes. Antimicrobial therapy was inadequate in three (12%) BSI episodes diagnosed using results of molecular testing. Our in-house rapid protocol for identifying both bacteria and antimicrobial resistance provided rapid and accurate results, having good agreement with conventional testing results. These results could contribute to faster antimicrobial therapy interventions in BSI episodes.
Subject(s)
Bacteremia/diagnosis , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/administration & dosage , Bacteremia/drug therapy , Bacteremia/microbiology , Child , Child, Preschool , Female , Gram-Negative Bacteria/genetics , Gram-Positive Bacteria/genetics , Humans , Infant , Male , Middle Aged , Prospective Studies , Real-Time Polymerase Chain Reaction , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Time Factors , Young AdultABSTRACT
ABSTRACT Bloodstream infections (BSIs) are serious infections associated with high rates of morbidity and mortality. Every hour delay in initiation of an effective antibiotic increases mortality due to sepsis by 7%. Turnaround time (TAT) for conventional blood cultures takes 48 h, forcing physicians to streamline therapy by exposing patients to broad-spectrum antimicrobials. Our objective was (1) to evaluate the accuracy and TAT of an optimized workflow combining direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and in-house real-time polymerase chain reaction (PCR) for bacterial identification and antimicrobial resistance profiling directly from positive blood bottles for diagnosing bloodstream infections and (2) to verify the effect of reporting results to medical staff. A total of 103 BSI episodes from 91 patients admitted to three hospitals in São Paulo, Brazil were included. TAT from molecular versus conventional methods was measured and compared. Our protocol showed an overall agreement of 93.5% for genus and 78.5% for species identification; 74.2% for methicillin resistance detection, 89.2% for extended-spectrum β-lactamase profiling, 77.8% for metallo-β-lactamase profiling, and 100% for carbapenemase profile and vancomycin-resistance detection when compared with conventional testing. TAT of molecular sample processing according to our protocol was 38 h shorter than conventional methods. Antimicrobial interventions were possible in 27 BSI episodes. Antimicrobial discontinuation was achieved in 12 BSI episodes while escalation of therapy occurred in 15 episodes. Antimicrobial therapy was inadequate in three (12%) BSI episodes diagnosed using results of molecular testing. Our in-house rapid protocol for identifying both bacteria and antimicrobial resistance provided rapid and accurate results, having good agreement with conventional testing results. These results could contribute to faster antimicrobial therapy interventions in BSI episodes.
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Bacteremia/diagnosis , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Time Factors , Prospective Studies , Bacteremia/microbiology , Bacteremia/drug therapy , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Real-Time Polymerase Chain Reaction , Gram-Negative Bacteria/genetics , Gram-Positive Bacteria/genetics , Anti-Bacterial Agents/administration & dosageABSTRACT
Background: Bloodstream infections (BI) are associated with high morbidity and mortality. Objective: To determine epidemiological, microbiological and clinical features of community (CA-BI) and nosocomial bloodstream infections (N-BI). Methods: Bacteremia and fungemia events were retrospectively analyzed in two third-level hospitals between April 2009 and August 2013. Results: We identified 1150 events of bloodstream infections, 53.2% were CA-BI. Gram negative microorganisms were isolated in 61%. The most frequent pathogens were Escherichia coli in CA-BI and Klebsiella pneumoniae in N-BI. Staphylococcus aureus was the most frequent gram positive organism. The main comorbidities were renal disease (39%) and malignancy (38%). There were 26.8% of primary bloodstream infections, and the main infection foci included respiratory (17.04%) and urinary tract (16.86%). A high percentage of gram-negative bacteria of CA-BI and N-BI were resistance to ampicillin sulbactam (40.2% and 57.5%), cephalothin (36.7% and 46.8%), trimethoprim-sulfamethoxazole 32.8% vs 35.5%) and ciprofloxacin (24.6% and 35.3%). Methicillin-resistant Staphylococcus aureus were more frequently into ITS-IH (31.4% vs 11.8%, p = 0.007). Conclusions: Clinical and epidemiological characteristics of CA-BI and N-BI were similar to those reported by other Latin-American studies. We observed some differences in antimicrobial resistance profiles. We emphasize the importance of local epidemiological surveillance to choose appropriate empirical treatments. Conclusions: Clinical and epidemiological characteristics of CA-BI and N-BI were similar to those reported by other Latin-American studies. We observed some differences in antimicrobial resistance profiles. We emphasize the importance of local epidemiological surveillance to choose appropriate empirical treatments.
Introducción: Las infecciones del torrente sanguíneo (ITS) generan elevada morbimortalidad. Objetivo: Determinar características epidemiológicas, microbiológicas y clínicas de ITS adquiridas en la comunidad (ITS-AC) e intrahospitalarias (ITS-IH). Métodos: Se analizaron retrospectivamente eventos de bacteriemia y fungemia en dos hospitales de tercer nivel entre abril de 2009 y agosto de 2013. Resultados: Se identificaron 1150 eventos de ITS, 53% ITS-AC. El 61% de microorganismos aislados fueron gram negativos. Los patógenos más frecuentes fueron Escherichia coli en ITS-AC y Klebsiella pneumoniae en ITS-IH. Staphylococcus aureus fue el gram positivo más frecuente. Las principales comorbilidades fueron enfermedad renal (39%) y neoplasias (38%). El 26,8% de ITS fueron primarias. Los focos infecciosos más frecuentes fueron respiratorio (17%) y urinario (16,9%). Un elevado porcentaje de gram negativos en ITS-AC e ITS-IH fueron resistentes a ampicilina sulbactam (40,2% y 57,5%), cefalotina (36,7% y 46,8%), trimetoprima-sulfametoxazol (32,8% vs 35,5%) y ciprofloxacina (24,6% y 35,3%). Staphylococcus aureus meticilino resistente fue más frecuente en ITS-IH (31,4% vs 11,8%, p=0,007). Conclusiones: Las características clínicas y epidemiológicas de ITS fueron similares a las reportadas por otros estudios latinoamericanos. Pero observamos algunas diferencias en los perfiles de susceptibilidad antimicrobiana. Resaltamos la importancia de la vigilancia epidemiológica local para elegir tratamientos empíricos apropiados.
Subject(s)
Bacteremia/microbiology , Cross Infection/microbiology , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Adolescent , Adult , Aged , Anti-Bacterial Agents/pharmacology , Argentina/epidemiology , Bacteremia/epidemiology , Bacteremia/mortality , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Community-Acquired Infections/mortality , Cross Infection/epidemiology , Cross Infection/mortality , Female , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/drug effects , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Retrospective Studies , Young AdultABSTRACT
ABSTRACT Purpose: The aim of this study was to analyze the bacterial and fungal microbiota found in contact lens cases among two groups of patients to correlate the data on the habits of contact lens users and to evaluate whether there is a difference in the culture results between users of ridged and nonridged contact lens cases. Methods: Two groups (35 patients per group) were included, consisting of hospital workers and those who had not visited a hospital in the past 30 days, and a questionnaire regarding epidemiological data and habits related to contact lens and lens case use was administered. In addition, 140 samples collected from the right and left compartments of each lens case by swabbing the bottom of the wells were tested using bacterioscopy as well as fungal and bacterial cultures via computerized identification of the species. Results: No fungal growth was identified in any of the 70 contact lens cases; however, bacteria were found in 39 cases, and there was no statistical difference between the groups. Most bacteria (>85%) were gram-negative bacilli. Contamination inone compartment of the contact lens case elevated the risk of contamination of the other side (>80%). Moreover, contamination was statistically higher in the ridged cases than in nonridged cases (p=0.0149). Conclusion: The types of bacteria contaminating the cases are generally not seen in eye diseases associated with contact lens use, suggesting that other decisive variables are involved in eye infection from a contaminated lens or case. Fungal contamination of contact lens cases appears to be an exception. Ridged cases are commonly used by contact lens wearers and present a potential risk to eye health. In addition, the results of bacterial tests between hospital workers and those who did not visit a hospital were not significantly different.
RESUMO Objetivo: O objetivo deste trabalho foi analisar a microbiota bacteriana e fúngica encontrada em estojos de lentes de contato em dois grupos, correlacionar os dados sobre os hábitos de uso de lentes de contato e avaliar se há diferença na positividade das culturas entre os usuários estojos de lentes de contato com ranhuras e sem ranhuras. Métodos: Dois grupos foram formados, trabalhadores do hospital e pessoas que não visitaram o hospital (35 indivíduos por grupo), e um questionário foi aplicado sobre dados epidemiológicos e hábitos relacionados ao uso de lentes de contato e estojos de lentes. Além disso, 140 amostras, coletadas do compartimento direito e esquerdo de cada estojo de lente, esfregando o fundo dos mesmos, foram testadas por bacterioscopia e por culturas de fungos e bactérias, com identificação computadorizada da espécie. Resultados: Não houve crescimento fúngico em nenhum dos 70 estojos de lentes de contato, porém bactérias foram encontradas em 39; não houve diferença estatística entre os grupos. A maioria das bactérias (>85%) eram bacilos gram-negativos. Quando um compartimento estava contaminado, o risco de contaminação do outro compartimento era elevado (>80%). A contaminação foi estatisticamente maior nos estojos com ranhuras (p=0,0149). Conclusão: A contaminação dos estojos parece ocorrer por bactérias que, em geral, não são encontradas em doenças oculares associadas ao uso de lentes de contato, sugerindo que existem outras variáveis decisivas nas infecções oculares de uma lente ou estojo contaminado. Contaminação de estojos de lentes de contato com fungos parece ser uma exceção. O uso de estojos com ranhuras é uma prática comum e apresenta um risco potencial à saúde ocular. Não foram encontradas diferenças significativas nos resultados dos testes bacterianos entre trabalhadores hospitalares e pessoas que não visitaram o hospital.
Subject(s)
Humans , Equipment Contamination/statistics & numerical data , Contact Lenses/microbiology , Gram-Negative Bacteria/isolation & purification , Equipment Contamination/prevention & control , Surveys and Questionnaires , Fungi/isolation & purification , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Gram-Positive Bacteria/classificationABSTRACT
PURPOSE: The aim of this study was to analyze the bacterial and fungal microbiota found in contact lens cases among two groups of patients to correlate the data on the habits of contact lens users and to evaluate whether there is a difference in the culture results between users of ridged and nonridged contact lens cases. METHODS: Two groups (35 patients per group) were included, consisting of hospital workers and those who had not visited a hospital in the past 30 days, and a questionnaire regarding epidemiological data and habits related to contact lens and lens case use was administered. In addition, 140 samples collected from the right and left compartments of each lens case by swabbing the bottom of the wells were tested using bacterioscopy as well as fungal and bacterial cultures via computerized identification of the species. RESULTS: No fungal growth was identified in any of the 70 contact lens cases; however, bacteria were found in 39 cases, and there was no statistical difference between the groups. Most bacteria (>85%) were gram-negative bacilli. Contamination inone compartment of the contact lens case elevated the risk of contamination of the other side (>80%). Moreover, contamination was statistically higher in the ridged cases than in nonridged cases (p=0.0149). CONCLUSION: The types of bacteria contaminating the cases are generally not seen in eye diseases associated with contact lens use, suggesting that other decisive variables are involved in eye infection from a contaminated lens or case. Fungal contamination of contact lens cases appears to be an exception. Ridged cases are commonly used by contact lens wearers and present a potential risk to eye health. In addition, the results of bacterial tests between hospital workers and those who did not visit a hospital were not significantly different.
Subject(s)
Contact Lenses/microbiology , Equipment Contamination/statistics & numerical data , Gram-Negative Bacteria/isolation & purification , Equipment Contamination/prevention & control , Fungi/isolation & purification , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Gram-Positive Bacteria/isolation & purification , Humans , Surveys and QuestionnairesABSTRACT
Passiflora species are well known for their common use in popular medicine for the treatment of several diseases, such as insomnia, anxiety, and hysteria, in addition to their anti-inflammatory, antioxidant, analgesic and antibacterial potential. However, few data about the chemical composition and the medicinal potential of in vitro derived materials are available. Therefore, the goal of this work was to compare, for the first time, the phytoconstituents of in vitro derived materials of four Passiflora species, and evaluate the antibacterial potential of their extracts against 20 Gram-positive and negative strains. Chromatographic analysis indicated the presence of saponins in roots extracts from all studied species, whereas leaf extracts presented both saponins and flavonoids. Extracts from leaves and roots of P. alata and P. foetida exhibited a selective inhibitory activity against B. thuringiensis and S. pyogenes, which might be related to the presence of a high concentration of secondary metabolites, including flavonoids and saponins.
Subject(s)
Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Passiflora/chemistry , Plant Extracts/pharmacology , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , Microbial Sensitivity Tests , Passiflora/classificationABSTRACT
BACKGROUND: Microorganisms isolated from blood cultures (BC) in patients with febrile neutropenia (NF) vary over time, requiring systematic monitoring to guide appropriate empirical therapy. AIM: To identify microorganisms isolated from BC and their antimicrobial resistance profile in children with cancer and high risk NF. METHOD: Prospective, multicenter study. The analysis included episodes of high-risk FN with positive BC in children under 18 years of age treated in five hospitals in Santiago, Chile, 2012-2015. RESULTS: A total of 206 microorganisms were analyzed in 185 episodes of high-risk FN. The main isolates were Gram negative bacilli (46.6%) and Gram positive cocci (45.1%) and the most frequent microorganisms were Escherichia coli (22.8%), coagulase negative Staphylococcus (18.0%) and Klebsiella spp. (16.5%). Escherichia coli and Klebsiella spp showed 4.2% and 67.6% resistance to third generation cephalosporins (cefotaxime/ceftriaxone), 10.6% and 40.6% resistance to fluoroquinolones (ciprofloxacin) and 2.1% and 26.5% to amikacin, respectively. Coagulase negative Staphylococcus and Staphylococcus aureus had 86.4% and 22.2% resistance to oxacillin, Streptococcus viridans group had 71% resistance to penicillin. DISCUSSION: This study updates the etiology and resistance profile of microorganisms isolated in BC from children with cancer and high risk FN, an essential tool for the adequate management of these patients.