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1.
BMC Infect Dis ; 20(1): 60, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959118

RESUMO

BACKGROUND: Necrotizing fasciitis (NF) is a rare and life-threatening necrotizing skin and soft-tissue infection. Infectious pathogens of NF must be detected early and treated rapidly to prevent loss of limb or a fatal outcome. This study aimed to detect more reliable predictors between gram-negative and gram-positive monomicrobial NF of limbs. METHODS: A total of 100 patients with limb monomicrobial NF were diagnosed prospectively from April 2015 to July 2018. These monomicrobial NF pathogens can be divided into gram-negative and gram-positive groups according to the result of Gram staining and final bacterial reports. Data such as demographics, seawater or seafood contact history, infectious location, comorbidities, presenting signs and symptoms, and laboratory findings were recorded and compared. RESULTS: A total of 55 patients were infected with gram-negative organisms and 45 patients with gram-positive organisms. Among the 55 cases of monomicrobial gram-negative NF, 48 (87.3%) were caused mainly by Vibrio spp. (38, 69.1%) and Aeromonas spp. (10, 18.2%). A higher incidence of chronic kidney disease, cerebrovascular accident, tachypnea, and septic shock; a higher rate of band forms of leukocytes of more than 3%, serum lactate of more than 20 mg/dL, and C-reactive protein level of less than 150 mg/dL; prolonged prothrombin time; and a lower fibrinogen level were observed in patients with gram-negative infection. In a multivariate analysis, a higher incidence of seawater or seafood contact history (odds ratio [OR]: 66.301; 95% confidence interval [CI]: 7.467-588.702), a higher rate of hyperlactatemia (OR: 7.904; 95% CI: 1.231-50.744), and a low fibrinogen level (OR: 1.013; 95% CI: 1.004-1.023) indicated gram-negative infection. CONCLUSIONS: In southern Taiwan, NF of limbs mainly affected the lower limbs, exhibited monomicrobial infection, and was predominated by gram-negative bacteria. Gram-negative monomicrobial NF of limbs often occurred in individuals with the more seawater or seafood contact history, hyperlactatemia, and low fibrinogen levels.


Assuntos
Aeromonas/isolamento & purificação , Fasciite Necrosante/epidemiologia , Fasciite Necrosante/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções dos Tecidos Moles/epidemiologia , Infecções dos Tecidos Moles/microbiologia , Vibrio/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Fasciite Necrosante/diagnóstico , Feminino , Infecções por Bactérias Gram-Negativas/diagnóstico , Humanos , Incidência , Extremidade Inferior/microbiologia , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Infecções dos Tecidos Moles/diagnóstico , Taiwan/epidemiologia
2.
Ecotoxicol Environ Saf ; 191: 110182, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958628

RESUMO

The gut of aquatic animals was a significant niche for dissemination of antibiotic resistance genes (ARGs) and direct response of living conditions. In this study, the gut microbiota of goldfish Carassius auratus Linnaeus was sampled at 7 days and 21 days after treatment with tetracycline at 0.285 and 2.85 µg L-1 to investigate the influences on the microbial structure and antibiotic resistance. The proportion of tetracycline resistance bacteria was 1.02% in the control group, while increased to 23.00%, 38.43%, 62.05% in groups of high concentration for 7 days (H7), low concentration for 21 days (L21) and high concentration for 21 days (H21), respectively. Compared to the control group, the diversity of isolated Aeromonas spp. was decreased in the treatment groups and the minimal inhibitory concentration (MIC) of resistant isolates was enhanced from 32 to 256 µg mL-1 with the treatment of tetracycline in time- and dose-dependent manners. Furthermore, the abundance of most genes was increased in treatment groups and efflux genes mainly responded to the stress of tetracycline with an average level of 1.0 × 10-2. After treatment with tetracycline, the predominant species were changed both at phylum and genus levels. The present study explored the impact of tetracycline on gut microbiota of goldfish at environmentally realistic concentrations for the first time and our findings will provide a reference for characterizing the microbiome of fish in the natural environment.


Assuntos
Aeromonas/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Carpa Dourada/microbiologia , Resistência a Tetraciclina/genética , Tetraciclina/toxicidade , Aeromonas/classificação , Aeromonas/genética , Aeromonas/isolamento & purificação , Animais , Antibacterianos/toxicidade , Exposição Ambiental/efeitos adversos , Genes Bacterianos , Testes de Sensibilidade Microbiana , Resistência a Tetraciclina/efeitos dos fármacos
3.
Lett Appl Microbiol ; 70(3): 221-229, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31854000

RESUMO

Hard-shelled mussel (Mytilus coruscus) is a popular seafood in Korea. This study aimed to determine the virulence markers and antimicrobial resistance patterns of 33 Aeromonas strains isolated from mussels. The isolates were identified as A. salmonicida (n = 14), A. veronii (n = 9), A. enteropelogenes (n = 4), A. caviae (n = 3), A. allosaccharophila (n = 2) and A. bivalvium (n = 1) by gyrB gene sequencing. The sequence divergence between and within the species ranged from 3·70 to 10·40% and 0-1·50% respectively. Every species formed a distinct group in a neighbour-joining phylogenetic tree. The DNase, gelatinase, caseinase, ß-haemolysis, biofilm and lipase activities were observed in 33 (100·00%), 31 (93·93%), 30 (90·90%), 27 (81·81%), 21 (63·63%) and 17 (51·51%) isolates respectively. The virulence genes were detected by PCR in the following frequencies: fla (90·09%), aer (87·88%), hlyA (87·88%), ahyB (81·19%), gcaT (75·76%), ser (69·70%), lip (66·67%), alt (57·58%), ast (51·51%) and act (21·21%). Every isolate was resistant to at least three of 18 antimicrobials in the disk diffusion test. The multiple antimicrobial resistance index values ranged from 0·11 to 0·44 among the isolates. Our study suggests that mussels can be a potential reservoir of virulent and multidrug-resistant Aeromonas sp. SIGNIFICANCE AND IMPACT OF THE STUDY: Aeromonas sp. are known as common pathogenic bacteria isolated from seafood. The virulence factors and antimicrobial resistance profiles of mussel-borne Aeromonas sp. are poorly understood. This study demonstrated for the first time the existence of virulence markers and antimicrobial resistance of Aeromonas sp. from mussels in Korea. Majority of the isolates were positive for phenotypic virulence characteristics and harboured several virulence genes which reveal the potential virulence of mussel-borne Aeromonas sp. Multiple antimicrobial resistance was also observed among the isolates. Our study highlights the importance of food safety standards in mussel consumption.


Assuntos
Aeromonas/classificação , Aeromonas/isolamento & purificação , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Mytilus/microbiologia , Aciltransferases/genética , Aeromonas/genética , Aeromonas/patogenicidade , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Infecções por Bactérias Gram-Negativas/microbiologia , Lipase/genética , Filogenia , Reação em Cadeia da Polimerase , República da Coreia , Alimentos Marinhos/microbiologia , Virulência/genética , Fatores de Virulência/genética
4.
J Fish Dis ; 42(12): 1637-1644, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31578759

RESUMO

Doctor fish (Garra rufa, Heckel, 1843) are increasingly used for cosmetic treatment raising particular concerns regarding the potential transmission of infections to clients. Investigations of microbial causes undertaken in two outbreaks of mortality among G. rufa used for cosmetic treatment revealed the presence of multiple bacteria, including both fish and human pathogens such as Aeromonas veronii, A. hydrophila, Vibrio cholerae, Shewanella putrefaciens, Mycobacterium marinum and M. goodii. This range of bacteria indicates an intense microbial proliferation involving multiple pathogens, most likely induced by the poor health condition of the fish. Most of the detected pathogens are well-known agents of zoonosis. Indeed, M. goodii is an emerging nosocomial human pathogen that has never been detected in fish to date, nor in other animals. This first detection of M. goodii associated with fish infection points out a new zoonotic potential for this pathogen. These findings point out that handling, poor environmental conditions and the presence of fish pathogens, that can compromise the immune system of fish, can result in a mixed microbial proliferation and increase the spread of waterborne bacteria, including zoonosis agents. Accordingly, the microbiological surveillance of fish used for cosmetic treatment is extremely important, particularly in association with mortality outbreaks.


Assuntos
Cyprinidae/microbiologia , Doenças dos Peixes/microbiologia , Aeromonas/isolamento & purificação , Animais , Técnicas Cosméticas , Surtos de Doenças/veterinária , Doenças dos Peixes/mortalidade , Humanos , Mycobacteriaceae/isolamento & purificação , Shewanella putrefaciens/isolamento & purificação , Vibrio cholerae/isolamento & purificação , Zoonoses/microbiologia
5.
Rev Fac Cien Med Univ Nac Cordoba ; 76(3): 154-158, 2019 08 29.
Artigo em Espanhol | MEDLINE | ID: mdl-31465182

RESUMO

Introduction: Aeromonas is a common cause of gastroenteritis but occasionally it can cause extraintestinal infections. The incidence of bacteremia by this genus is very low and in general the patients have associated base diseases. Materials and methods: Retrospective analysis of episodes of bacteremia by Aeromonas spp. during a period of eight years in the National Hospital of Clinics of the city of Córdoba, emphasizing age, sex, associated comorbidities, clinical presentation, focus, origin of the infection, clinical evolution, species prevalence and antimicrobial sensitivity of the same . Results: 10 episodes of bacteremia were recorded by Aeromonas spp. 60% corresponded to women and 40% to men. The average age was 65 years. In seven patients the origin of the infection was community and in three nosocomial. 70% of the patients presented predisposing base pathologies. The focus of bacteremia was abdominal in two cases. A. hydrophila complex was responsible for 50% of the cases. 80% of bacteremia were monomicrobial. The isolates generally showed high percentages of sensitivity. Conclusion: Bacteremia occurred in elderly patients of both sexes, most of whom had associated comorbidities. The majority of the infections originated in the community. While bacteremia by Aeromonas spp. it is rare, the mortality found in our study was relatively high despite the high percentage of sensitivity to antimicrobials.


Assuntos
Aeromonas/isolamento & purificação , Bacteriemia/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/classificação , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Comorbidade , Resistência a Medicamentos , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
J Appl Microbiol ; 127(3): 941-952, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31211903

RESUMO

AIMS: Manila clam (Ruditapes philippinarum) is one of the most popular seafood in Korea, owing to their unique taste and nutritional value. This study aimed to disclose the antibiotic and heavy metal resistance characteristics of Aeromonas spp. isolated from marketed Manila clam in Korea. METHODS AND RESULTS: A total of 36 Aeromonas spp. strains were isolated and subjected to two tests: an antibiotic disk diffusion test to determine their resistance to antibiotics, and a broth dilution test to determine their resistance to heavy metals. PCR-based amplification was performed to detect the resistance genes. A high level of resistance to ampicillin (100%) and cephalothin (89%) was observed, while 42, 39, 36 and 36% of the isolates were resistant to oxytetracycline, imipenem, nalidixic acid and tetracycline respectively. In addition, among the tested heavy metals, cadmium (Cd) recorded the highest resistance rate (61%), followed by chromium (Cr) (50%), lead (Pb) (47%) and copper (Cu) (37%). However, mercury (Hg) resistance was not observed. PCRs revealed the occurrence of blaTEM , blaSHV , blaCTX-M , qnrS, tetB, tetE, aac(6')-Ib, strA-strB and intI1 genes among 100, 31, 31, 78, 78, 89, 25, 50 and 72% of the isolates respectively. Moreover, heavy metal resistance genes, copA, merA and czcA were detected in 25, 47 and 61% of the isolates respectively. CONCLUSIONS: The results suggest the importance of multi-drug and heavy metal-resistant aeromonads in Manila clam to assess the consumer safety and public health. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first to elaborate on the importance of multi-drug and heavy metal-resistant aeromonads in Manila clam. Particularly, the presence of extended-spectrum-ß-lactamase genes and other antibiotic resistance genes intensifies the possible health risks and may complicate therapeutic treatments upon infection, while heavy metal resistance suggests possible heavy metal exposure.


Assuntos
Aeromonas/efeitos dos fármacos , Antibacterianos/farmacologia , Bivalves/microbiologia , Resistência Microbiana a Medicamentos/genética , Metais Pesados/farmacologia , Aeromonas/genética , Aeromonas/isolamento & purificação , Animais , Humanos , Reação em Cadeia da Polimerase , República da Coreia
7.
J Vet Emerg Crit Care (San Antonio) ; 29(4): 444-449, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31240801

RESUMO

OBJECTIVE: To describe the clinical presentation, diagnostic investigation, and medical management of a dog on immunosuppressive therapy that developed a severe soft tissue infection attributed to Aeromonas hydrophila/caviae. CASE SUMMARY: A 5-year-old female neutered Border Collie dog was presented for investigation of a rapidly growing skin lesion. The dog had been diagnosed with immune-mediated thrombocytopenia and was receiving immunosuppressive therapy for 5 weeks. Physical examination at initial presentation revealed no abnormalities except a 6 cm raised, erythematous, firm, and painful swelling on the ventral abdomen. Within 12 hours of admission, the lesion had expanded to cover much of the ventrum and some areas had begun to slough. The patient had also become obtunded and exhibited pyrexia, tachypnea, tachycardia as well as extreme pain around the lesion. The dog's clinical signs and hematology results were consistent with sepsis. Histopathology showed severe acute suppurative cellulitis and panniculitis and a heavy growth of A. hydrophila/caviae was obtained on tissue culture. The infection was treated with trimethoprim sulphadiazine, based on culture and susceptibility results. UNIQUE INFORMATION PROVIDED: This is the first reported case of severe panniculitis and cellulitis caused by Aeromonas spp. in a dog. Aeromonas spp. should be considered a differential diagnosis for cases of severe soft tissue infection, especially in immune-compromised animals or those with a history of aquatic exposure.


Assuntos
Aeromonas/isolamento & purificação , Celulite (Flegmão)/veterinária , Doenças do Cão/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Sepse/veterinária , Trombocitopenia/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , Celulite (Flegmão)/microbiologia , Cães , Combinação de Medicamentos , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Sepse/microbiologia , Sulfadiazina/uso terapêutico , Trimetoprima/uso terapêutico
8.
PLoS One ; 14(6): e0218650, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31242271

RESUMO

Carbapenemase-producing bacteria (CPB) are rare, multidrug resistant organisms most commonly associated with hospitalized patients. Metropolitan wastewater treatment plants (WWTP) treat wastewater from large geographic areas which include hospitals and may serve as epidemiologic reservoirs for the maintenance or expansion of CPB that originate from hospitals and are ultimately discharged in treated effluent. However, little is known about the potential impact of these WWTP CPB on the local surface water and their risk to the public health. In addition, CPB that are present in surface water may ultimately disseminate to intensively-managed animal agriculture facilities where there is potential for amplification by extended-spectrum cephalosporins. To better understand the role of WWTPs in the dissemination of CPB in surface waters, we obtained samples of treated effluent, and both upstream and downstream nearby surface water from 50 WWTPs throughout the US. A total of 30 CPB with clinically-relevant genotypes were recovered from 15 WWTPs (30%) of which 13 (50%) serviced large metropolitan areas and 2 (8.3%) represented small rural populations (P < 0.05). Recovery of CPB was lowest among WWTPs that utilized ultraviolet radiation for primary disinfection (12%), and higher (P = 0.11) for WWTPs that used chlorination (42%) or that did not utilize disinfection (50%). We did not detect a difference in CPB recovery by sampling site, although fewer CPB were detected in upstream (8%) compared to effluent (20%) and downstream (18%) samples. Our results indicate that WWTP effluent and nearby surface waters in the US are routinely contaminated with CPB with clinically important genotypes including those producing Klebsiella pneumoniae carbapenemase (KPC) and New Delhi metallo-beta-lactamase (NDM). This is a concern for both public health and animal agriculture because introduction of CPB into intensively managed livestock populations could lead to their amplification and foodborne dissemination.


Assuntos
Aeromonas/isolamento & purificação , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Águas Residuárias/microbiologia , Aeromonas/genética , Animais , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Reservatórios de Doenças/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Água Subterrânea/microbiologia , Hospitais , Humanos , Resíduos de Serviços de Saúde , Estados Unidos , Purificação da Água
9.
J Appl Microbiol ; 127(2): 418-428, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31136041

RESUMO

AIMS: Under intensive and stressful aquaculture conditions, cultured eels are highly susceptible to virulent Aeromonas sp. infections. To rapidly and simultaneously confirm Aeromonas isolate and its virulence, a two-tube multiplex PCR (mPCR) assay incorporating gyrB gene for genus-specific recognition and seven major virulence genes for virulence assessment was developed. METHODS AND RESULTS: Eight pairs of primers were designed and divided into two groups-gyrB, ahpA, epr and aerA in tube 1 and alt, act, ast and hlyA in tube 2. The optimized mPCR conditions were the same except for their final concentrations. The specificity of the mPCR was validated by the extracted DNA of 10 Aeromonas and 8 non-Aeromonas species, or mixed DNA templates. Detection limits were determined to be 200 copies per µl in tube 1 and 20 copies per µl in tube 2. The mPCR reproducibility was tested by both artificial challenge and clinical samples. CONCLUSIONS: The results showed this two-tube mPCR assay was rapid, specific, sensitive and reliable. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first report to distinguish virulent Aeromonas isolates from nonvirulent ones by seven popular and major virulence genes at the genus-specific level. And it will be useful for large-scale screening of virulent Aeromonas sp. in cultured eels.


Assuntos
Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Enguias/microbiologia , Reação em Cadeia da Polimerase Multiplex/métodos , Aeromonas/genética , Animais , Aquicultura , Primers do DNA , Reprodutibilidade dos Testes , Fatores de Virulência/genética
10.
Semin Diagn Pathol ; 36(3): 187-192, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31036328

RESUMO

Knowledge of the pathogenic roles of certain bacterial agents in gastroenteritis has been growing over the past few decades. With the increasing use of multiplex molecular-based syndromic stool pathogen panels, the roles of Plesiomonas shigelloides and some of the diarrheagenic pathotypes of Escherichia coli (enterotoxigenic E. coli [ETEC], enteropathogenic E. coli [EPEC], enteroinvasive E. coli [EIEC], and enteroaggregative E. coli [EAEC]) have been better understood. Although not currently targeted on Food and Drug Administration (FDA)-cleared commercial multiplex stool panels, Aeromonas has also emerged as a possible cause of bacterial gastroenteritis. The clinical presentation, pathophysiology, and diagnostic approaches to these pathogens in stool specimens are reviewed. Variability in inclusion of these pathogens on multiplex molecular panels and difficulties in detection by stool culture techniques utilized by clinical microbiology laboratories have contributed to an unclear understanding of the pathogenic role of several of these pathogens. Nonetheless, most evidence points towards a clear pathogenic role for P. shigelloides and ETEC, and possibly EPEC and EIEC. The contribution of Aeromonas spp. and EAEC to bacterial gastroenteritis has not been fully established. Further studies of pathogenicity of these pathogens are needed.


Assuntos
Aeromonas/isolamento & purificação , Infecções Bacterianas/patologia , Doenças Transmissíveis Emergentes/patologia , Diarreia/patologia , Escherichia coli/isolamento & purificação , Gastroenterite/patologia , Plesiomonas/isolamento & purificação , Infecções Bacterianas/diagnóstico , Doenças Transmissíveis Emergentes/diagnóstico , Doenças Transmissíveis Emergentes/microbiologia , Diarreia/diagnóstico , Diarreia/microbiologia , Fezes/microbiologia , Gastroenterite/diagnóstico , Gastroenterite/microbiologia , Humanos
11.
Lett Appl Microbiol ; 69(2): 100-109, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31107978

RESUMO

Members of the genus Aeromonas are opportunistic pathogen of a variety of aquatic animals that exhibits multidrug resistance, phenotypes, virulence genes and virulence. The present study described the species distribution and the potential pathogenicity of Aeromonas isolated from healthy Northern snakehead (Channa argus) in China. Molecular identification revealed that A. veronii biovar veronii (69/167; 41·3%) and A. hydrophila (41/167; 24·6%) were the most common species found in Northern snakehead intestine based on sequencing of the 16S rRNA gene and DNA gyrase subunit B protein. The distribution of seven virulence factors including aer (84·4%), act (80·8%), ser (40·1%), Aha (27·5%), lip (23·4%), exu (15·0%) and LuxS (12·6%) were determined exclusively in Aeromonas isolates. All the seven virulence genes were present in 9·6% (16/167), among which 11 strains were identified as A. veronii biovar veronii. For the strains harbouring seven virulence genes, the 50% lethal doses (LD50 ) of isolates were lower compared to the isolates carrying two virulence genes. The challenge tests revealed that isolate W31 had the lowest lethal dose, causing 50% mortality at 4·5 × 103 colony-forming units (CFU) per ml. Furthermore, histopathology of Northern snakehead infected with Aeromonas strains showed necrosis and congestion in liver, spleen and kidney and also damage to the intestine. This study confirms that the Aeromonas strains isolated from healthy Northern snakehead may be a cause of concern for public health. SIGNIFICANCE AND IMPACT OF THE STUDY: Aeromonas species are widely distributed in aquatic environments and have considerable virulence potential. The aim of this study was to identify Aeromonas strains isolated from healthy Northern snakehead, and to investigate if Aeromonas species isolated from healthy fish potential pathogenicity with special reference to virulence and epidemiology studies.


Assuntos
Aeromonas/patogenicidade , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Fatores de Virulência/genética , Aeromonas/genética , Aeromonas/isolamento & purificação , Animais , Proteínas de Bactérias/genética , China/epidemiologia , DNA Girase/genética , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/patologia , Peixes , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/patologia , Humanos , Saúde Pública , Virulência/genética
12.
Lett Appl Microbiol ; 69(1): 2-10, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30980564

RESUMO

Aeromonas sp. are opportunistic pathogenic bacteria which are associated with various diseases in ornamental fish, aquaculture raised species and wild fisheries. In our study, antimicrobial resistance patterns, antimicrobial resistance genes and class 1 integron gene cassettes of 52 guppy-borne Aeromonas sp. were examined. The isolates were identified as A. veronii (n = 34), A. dhakensis (n = 10), A. hydrophila (n = 3), A. caviae (n = 3) and A. enteropelogenes (n = 2) by gyrB gene sequencing. Every isolate was resistant to at least four antimicrobials in disc diffusion test. The resistance to amoxicillin, nalidixic acid and oxytetracycline was 100% among the tested isolates. 92·30, 76·92, 71·15, 51·92, 51·92 and 50·00% of the isolates were resistant to ampicillin, rifampicin, imipenem, cephalothin, tetracycline and trimethoprim respectively. The multiple antibiotic resistance index values ranged from 0·28 to 0·67. PCR amplification of antimicrobial resistance genes implied the occurrence of tetracycline resistance (tetA (65·39%), tetE (25·00%) and tetB (15·38%)), plasmid-mediated quinolone resistance (qnrS (26·92%) and qnrB (17·31%)) and aminoglycoside resistance (aphaAI-IAB (7·69%) and aac (6')-Ib (3·84%)) genes in the isolates. The IntI gene was positive for 36·54% of the isolates and four class 1 integron gene cassette profiles (aadA2, qacE2-orfD, aadA2-catB2 and dfrA12-aadA2) were identified. These data suggest that ornamental guppy can be a reservoir of multidrug-resistant Aeromonas sp. which comprise different antimicrobial resistance genes and class 1 integrons. SIGNIFICANCE AND IMPACT OF THE STUDY: Antimicrobial resistance genes and integron gene cassettes of ornamental fish-borne aeromonads are poorly studied. The antimicrobial resistance patterns, antimicrobial resistance genes and class 1 integron gene cassettes of Aeromonas sp. isolated from ornamental guppy were characterized for the first time in Korea. The incidence of different antimicrobial resistance genes and class 1 integron gene cassettes were observed in multidrug-resistant Aeromonas isolates. This result suggests that better management practices are necessary to prevent and address the serious consequences of indiscriminate and inappropriate antimicrobial use, and the distribution of multidrug-resistant bacteria.


Assuntos
Aeromonas/efeitos dos fármacos , Aeromonas/genética , Farmacorresistência Bacteriana Múltipla/genética , Integrons/genética , Poecilia/microbiologia , Aeromonas/isolamento & purificação , Animais , Antibacterianos/farmacologia , Aquicultura , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , República da Coreia
13.
Microb Pathog ; 130: 81-94, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849490

RESUMO

The genus Aeromonas comprises more than thirty Gram-negative bacterial species which mostly act as opportunistic microorganisms. These bacteria are distributed naturally in diverse aquatic ecosystems, where they are easily isolated from animals such as fish and crustaceans. A capacity for adaptation also makes Aeromonas able to colonize terrestrial environments and their inhabitants, so these microorganisms can be identified from different sources, such as soils, plants, fruits, vegetables, birds, reptiles, amphibians, among others. Infectious processes usually develop in immunocompromised humans; in fish and other marine animals this process occurs under conditions of stress. Such events are most often associated with incorrect practices in aquaculture. Aeromonas has element diverse ranges, denominated virulence factors, which promote adhesion, colonization and invasion into host cells. These virulence factors, such as membrane components, enzymes and toxins, for example, are differentially expressed among species, making some strains more virulent than others. Due to their diversity, no single virulence factor was considered determinant in the infectious process generated by these microorganisms. Unlike other genera, Aeromonas species are erroneously differentiated by conventional biochemical tests. Therefore, molecular assays are necessary for this purpose. Nevertheless, new means of identification have been considered in order to generate methods that, like molecular tests, can correctly identify these microorganisms. The main objectives of this review are to explain environmental and structural characteristics of the Aeromonas genus and to discuss virulence mechanisms that these bacteria use to infect aquatic organisms and humans, which are important aspects for aquaculture and public health, respectively. In addition, this review aims to clarify new tests for the precise identification of the species of Aeromonas, contributing to the exact and specific diagnosis of infections by these microorganisms and consequently the treatment.


Assuntos
Aeromonas/classificação , Aeromonas/isolamento & purificação , Doenças dos Animais/microbiologia , Microbiologia Ambiental , Infecções por Bactérias Gram-Negativas/veterinária , Doenças das Plantas/microbiologia , Aeromonas/patogenicidade , Animais , Técnicas Bacteriológicas/métodos , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Técnicas de Diagnóstico Molecular/métodos , Virulência , Fatores de Virulência/genética
14.
BMC Infect Dis ; 19(1): 158, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30764764

RESUMO

BACKGROUND: Clinical characteristics (taxonomy, virulence genes and antimicrobial resistance ) of Aeromonas in isolated from extra-intestinal and intestinal infections were investigated to describe epidemiology, associated virulence factors and optimal therapy options. METHODS: Clinical samples (n = 115) of Aeromonas were collected from a general hospital in Beijing between the period 2015 and 2017. Taxonomy was investigate by Multilocus phylogenetic analysis (MLPA), 10 putative virulence factors by use of polymerase chain reaction (PCR) and antimicrobial resistance to 15 antibiotics by use of the microbroth dilution method. RESULTS: The most common species of Aeromonas detected in samples of intestinal tract included; A. caviae (43.9%), A. veronii (35.7%), and A. dhakensis (12.2%). Prevalent species of Aeromonas collected from extra-intestinal infections included; A. hydrophila (29.4%), A. caviae (29.4%), and A. dhakensis (23.5%). A. hydrophila were detected in 1% of stool samples and 29.4% (5/17) of extra-intestinal infections. A. hydrophila strains in extra-intestinal infections were related to malignancy. The most common medical conditions among patients with Aeromonas infections included malignancy and liver-transplant related cholecystitis. Multiple drug resistance (MDR) was prevalent in extra-intestinal isolates (82.3%, 14/17) and was greater than the prevalence in intestinal isolates (30.6%, 30/98) (P < 0.05). Resistant rates of extra-intestinal isolates were 70.6, 35.3, 23.5 and 5.9% for ceftriaxone, ciprofloxacin, gentamicin and imipenem, respectively, and were higher than found in previous studies. Despite differences in the number and type of virulence genes among samples of Aeromonas, no significant correlation was found between invasion and virulent genes in intestinal or extra-intestinal infections. CONCLUSIONS: Overall results of this study support a role for Aeromonas spp. as a potential causative infectious agent of gastroenteritis, and malignancy, liver cirrhosis, post liver transplantation in immunocompromised patients. A. hydrophila was more prevalent in samples of extra-intestinal infections when compared to samples of intestinal infections, and was especially prominent in samples of patients presenting with malignancy. Aeromonas isolates from extra-intestinal samples had high rates of drug resistance but 3rd generation cephalosporins, fluoroquinolones and aminoglycosides remain as options to treat severe diarrhea. However, increasing MDR of extra-intestinal infection samples warrants monitoring.


Assuntos
Aeromonas/classificação , Aeromonas/isolamento & purificação , Farmacorresistência Bacteriana , Infecções por Bactérias Gram-Negativas/microbiologia , Enteropatias/microbiologia , Infecções Intra-Abdominais/microbiologia , Fatores de Virulência/genética , Adolescente , Adulto , Aeromonas/efeitos dos fármacos , Aeromonas/genética , Antibacterianos/uso terapêutico , Técnicas de Tipagem Bacteriana , Criança , Pré-Escolar , China/epidemiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Feminino , Gastroenterite/tratamento farmacológico , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/epidemiologia , Humanos , Hospedeiro Imunocomprometido , Enteropatias/tratamento farmacológico , Enteropatias/epidemiologia , Infecções Intra-Abdominais/tratamento farmacológico , Infecções Intra-Abdominais/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Filogenia , Prevalência , Virulência/genética , Adulto Jovem
15.
Microb Pathog ; 127: 198-201, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30500410

RESUMO

The Aeromonas genus has several virulence factors associated with the development of diseases in aquatic organisms, leading to losses in aquaculture. One of these factors is the flagella's formation which allows the biofilm's formation that provides the microorganisms a greater pathogenicity, greater protection to certain substances such as antibiotics. The aim of the study was to verify the presence of the fla gene, related to biofilm production in isolates of Aeromonas spp. from fishes and also to determine the best quantification condition of phenotypic biofilm production in vitro. Polymerase Chain Reactions were performed to obtain the amplification of the region comprising the fla gene. To determine the best condition for the production biofilm, the microplate adhesion test was carried out under different concentrations of TSB broth and it combined with glucose. Of the 43 isolates of Aeromonas spp. analyzed, 28 were positive for the fla gene and, in the quantification of the biofilm, all these were able to form biofilm in the TSB broth without dilution and without addition of glucose, being this the best condition tested. It was observed that the isolates of Aeromonas spp. analyzed have potential for biofilm formation, and hence potential for virulence.


Assuntos
Aeromonas/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Meios de Cultura/química , Flagelos/genética , Glucose/metabolismo , Aeromonas/genética , Aeromonas/isolamento & purificação , Aeromonas/metabolismo , Animais , Doenças dos Peixes/microbiologia , Peixes , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Reação em Cadeia da Polimerase
16.
Infect Disord Drug Targets ; 19(3): 269-273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30179147

RESUMO

INTRODUCTION: Aeromonas have recently emerged as opportunistic pathogens and only a few studies are available regarding the isolation of these bacteria from burn wound infections. This study aimed at isolating Aeromonas as an infrequent cause of infection in this group of immunocompromised patients. METHODS: A total of 300 samples were collected from the wounds of burn patients hospitalized in Gotbodin Shirazi Burn Center in 2013. The samples were cultured on Aeromonas specific media and then confirmed using standard biochemical tests and 16S rRNA gene amplification and sequencing. The antibiotic susceptibility of the isolates was determined using the disk diffusion and broth microdilution methods. RESULTS: Biochemical tests demonstrated five presumptive samples of Aeromonas, while, molecular testing confirmed only three. All isolates were resistant to ampicillin-sulbactam, erythromycin, oxacillin, and vancomycin. However, they were susceptible to gentamicin, meropenem, nitrofurantoin, chloramphenicol, cephalexin, and cefotaxime. Two Aeromonas veronii isolates were resistant to sulfamethoxazole-trimethoprim and sensitive to nalidixic acid, while Aeromonas bestiarum was sensitive to the former and resistant to the latter antibiotics. Lastly, only one of the A. veronii isolates was found to be resistant to tetracycline. CONCLUSION: This study is the first to report on the isolation of Aeromonas spp. from burn patients in Iran. Moreover, this is the first report of isolating A. bestiarum from burn wounds. The results of this study confirm earlier findings that the use of molecular methods is essential to accurately identify these bacteria.


Assuntos
Aeromonas/genética , Aeromonas/isolamento & purificação , Queimaduras/microbiologia , Infecção dos Ferimentos/microbiologia , Adulto , Aeromonas/efeitos dos fármacos , Antibacterianos/farmacologia , Coinfecção/microbiologia , Estudos Transversais , Farmacorresistência Bacteriana , Feminino , Humanos , Hospedeiro Imunocomprometido , Irã (Geográfico) , Masculino , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética , Adulto Jovem
17.
J Appl Microbiol ; 126(1): 288-299, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30218592

RESUMO

AIMS: Yesso scallop (Patinopecten yessoensis) is a popular seafood in Korea. Aeromonas spp., well-known pathogenic bacteria, has been reported in some molluscan shellfish, but it has not been studied in scallops so far. Therefore, we aimed to isolate, identify and characterize the Aeromonas spp. isolated from marketed Yesso scallops to estimate their potential risk to public health. METHODS AND RESULTS: Thirty-two Aeromonas spp. including A. hydrophila (n = 13), A. salmonicida (n = 11), A. media (n = 3), A. caviae (n = 2), A. veronii (n = 2) and A. enteropelogenes (n = 1) were isolated from 105 marketed scallops and tested for phenotypic pathogenicity, virulence genes and antimicrobial susceptibility. Mean total bacterial count of scallop meat was 1·34 × 104 CFU per gram. Slime production and lipase tests were positive in 97% of the isolates while DNase, protease, gelatinase, phospholipase and haemolysis were shown by 88, 88, 81, 88 and 72% of the isolates respectively. Eleven virulence genes were detected among Aeromonas spp. (act (75%), alt (59%), ast (47%), aerA (78%), lip (59%), ahyB (94%), ser (75%), hlyA (75%), fla (64%), gcat (84%) and ascV (23%)), and exu was negative in all isolates. Aeromonas hydrophila and A. salmonicida harboured ≥7 virulence genes and positive for enterotoxin genes, act, alt and ast. All the isolates were multidrug resistant and 100% resistant to ampicillin, colistin, vancomycin and cephalothin. Also, 30, 31, 20, 21, 29, 24, 27 and 27 of the isolates were resistant to piperacillin, clindamycin, erythromycin, nalidixic acid, imipenem, meropenem, trimethoprim-sulfamethoxazole and rifampicin respectively. CONCLUSIONS: It is obvious with our results that the Aeromonas spp. isolated from Yesso scallops are highly virulent and potentially pathogenic, whereas the multidrug resistance further expedite their importance. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first study reporting Aeromonas spp. in scallop. This implies that not only the common varieties like oysters, but other bivalves can also harbour potentially pathogenic aeromonads which may have impacts on consumer health.


Assuntos
Aeromonas , Pectinidae/microbiologia , Alimentos Marinhos/microbiologia , Aeromonas/efeitos dos fármacos , Aeromonas/genética , Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Animais , Antibacterianos/farmacologia , Filogenia , Virulência/genética
18.
J Fish Dis ; 42(1): 109-117, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30474192

RESUMO

Aeromonas schubertii is a major epidemiological agent that threatens cultured snakeheads (Channidae) and has caused great economic losses in fish-farming industries in China in recent years. In present study, a specific TaqMan minor groove binder (MGB) probe fluorescence real-time quantitative PCR (qPCR) assay was developed to rapidly detect and quantify A. schubertii. A pair of qPCR primers and a TaqMan MGB probe were selected from the rpoD gene, which were shown to be specific for A. schubertii. A high correlation coefficient (R2  = 0.9998) in a standard curve with a 103% efficiency was obtained. Moreover, the qPCR method's detection limit was as low as 18 copies/µl, which was 100 times more sensitive than that of conventional PCR. The detection results for the A. schubertii in pond water and fish tissue were consistent with those of the viable counts. Bacterial load changes detected by qPCR in different tissues of snakeheads infected with A. schubertii showed that the gills and intestines may be the entry for A. schubertii, and the spleen and kidney are major sites for A. schubertii replication. The established method in present study should be a useful tool for the early surveillance and quantitation of A. schubertii.


Assuntos
Aeromonas/isolamento & purificação , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Reação em Cadeia da Polimerase em Tempo Real/métodos , Aeromonas/genética , Animais , Carga Bacteriana , Primers do DNA , Peixes/microbiologia , Fluorescência , Tanques/microbiologia , Sensibilidade e Especificidade , Microbiologia da Água
19.
J Microbiol Methods ; 156: 34-39, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471310

RESUMO

Plant-associated bacteria produce quorum sensing (QS) signals for community (biofilm) formation and functioning in the rhizosphere. The QS-positive biofilm-forming rhizobacteria that excel benefits to the plants are now gaining increased importance for agricultural use due to their high competitiveness. However, there is no method available to distinguish these bacteria from the roots of a plant to ease the isolation. Currently, all the plant-associated bacteria have to be isolated, purified and subsequently screened for the QS activity using biosensor strains. This study describes a direct isolation method for N-acyl-homoserine lactone (AHL) type quorum sensing signal producing bacteria from the plant root. In this method, the root sample collected from the field was overlaid directly with the bacterial growth medium seeded with the biosensor reporter, Chromobacterium violaceum (CV026). The AHL produced by QS positive rhizobacteria residing on the surface of the root will be recognized by violacein production of CV026. The bacterial isolates recovered from rice root using this method were further confirmed for the QS activity and biofilm formation. All the QS-positive strains produced N-butyryl DL-homoserine lactone (a C4-AHL type) signal in the culture medium and had biofilm formation during in vitro culturing. The 16S rRNA gene sequences of these QS-positive biofilm-forming rhizobacteria revealed that these strains are phylogenetically close to Pseudomonas siluiensis, Aeromonas hydrophila and A. caviae. Therefore, this could be a simple, rapid and straightforward procedure for isolation and characterization of quorum-sensing rhizobacteria from plant roots.


Assuntos
Aeromonas , Biofilmes/crescimento & desenvolvimento , Oryza/microbiologia , Raízes de Plantas/microbiologia , Pseudomonas , Percepção de Quorum , Acil-Butirolactonas/química , Aeromonas/classificação , Aeromonas/isolamento & purificação , Microbiota , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , Rizosfera
20.
Prev Vet Med ; 167: 190-195, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29685809

RESUMO

Diagnostic tools for the identification and confirmation of animal diseases have been evolving rapidly over the last decade, with diseases of aquatic animals being no exception. Hence, case definitions used in surveillance may now include molecular and genomic components and ultimately be based on the entire genome of a pathogen. While the opportunities brought on by this change in our ability to define and differentiate organisms are manifold, there are also challenges. These include the need to consider typing tool characteristics during sampling design, but also the re-thinking of diagnostic protocols and standards for the meaningful interpretation of the increasingly complex data presented to surveillance managers. These issues are illustrated for aquaculture using the example of multi-country surveillance of antimicrobial resistance of Aeromonas spp. strains isolated from rainbow trouts (Oncorhynchus mykiss) in Europe. In order to fully exploit the opportunities of molecular and genomic information, a multi-disciplinary approach is needed to develop harmonised diagnostic procedures and modified surveillance designs for aquaculture as well as for terrestrial animal production. This will require adjustments in the relevant standards applicable to assess food safety and trade risks.


Assuntos
Aquicultura/métodos , Aquicultura/organização & administração , Tomada de Decisões , Doenças dos Peixes/epidemiologia , Genômica , Aeromonas/genética , Aeromonas/isolamento & purificação , Animais , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Humanos , Modelos Biológicos , Epidemiologia Molecular , Oncorhynchus mykiss , Vigilância da População
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