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Background: Mostly intensive care unit (ICU) patients are more susceptible to nosocomial infections caused by hospital-based various strains of bacteria and other opportunistic pathogens. Due to the widespread use of broad-spectrum antibiotics, these strains of pathogens are often multi-drug resistant. To prevent resistance against the antimicrobial agent various departments of the health care system have to work together, so we can use the antimicrobial agents as effectively as we can to treat illnesses. Aim and Objectives: The objective of this study was to know the prevalence of different micro-organisms causing infections in ICU and their sensitivity and resistance pattern and to determine the overall microbiological and resistance profile which helps formulate therapeutic guidelines in ICU. Materials and Methods: A cross-sectional study was conducted at a tertiary care teaching hospital in Ahmedabad to assess the culture and sensitivity pattern of clinical samples such as blood, urine, sputum, wound, and endotracheal aspiration for a 1-year duration (August 2019 - August 2020). Results: A total of 941 samples were received for microbiological investigation from ICU, out of which 322 were positive. The Utmost isolated organism was - Klebsiella (37.26%) followed by Escherichia coli (16.45%), Pseudomonas (12.42%), and Staphylococcus aureus (7.45%). The Gram-negative bacteria (GNB) were most sensitive to drugs like colistin (96.26% %) and tigecycline (83.40%) followed by carbapenems (71.79%), aminoglycosides (71.36%), and fluoroquinolones (67.21%). More sensitive drugs for isolated Gram-positive organisms were linezolid (100%) followed by teicoplanin (98.41%) and vancomycin (98.41%). Conclusion: High prevalence of multidrug-resistant organisms such as methicillin-resistant S. aureus, vancomycin-resistant enterococci and GNB producing Extended-spectrum Beta-lactamase, AmpC, or carbapenem-resistant GNB in our study, raise serious concerns about antibiotic resistance. The main reason for increasing antimicrobial-resistant bacteria is poor infection control practices and inappropriate use of antibiotics. Hence, research regarding antibiotic sensitivity and resistance will be very helpful for doctors to initiate appropriate empirical antibiotics in treating critical illnesses.
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Objective:Streptococcus mutans is one of the etiological agents associated with caries due to its ability to metabolize carbohydrates and resist acidic environments. On the other hand, Streptococcus dentisani, shows characteristics associated with caries control due to its ability to inhibit growth of cariogenic bacteria. The aim of this work was to quantify the levels of Streptococcus mutans and Streptococcus dentisani from dental biofilm of children related to their caries situation. Material and Methods: After identification of morphologic characteristics of reference strains was performed, clinical isolates of biofilm compatible with these strains were selected and the Polymerase Chain Reaction technique was performed using species-specific primers. Biofilm samples from 25 children with caries and 21 without caries were collected to quantify the levels of S. mutans and S. dentisani. Results: There were statistically significant differences in the levels of S. mutans in the caries group and the levels increased as the severity of the carious lesion increased. By contrast, higher levels of S. dentisaniwere found in the caries-free group, although no statistically significant differences were found. In addition, the levels of S. dentisani decreased as the severity of the carious lesion increased. Conclusion: The increase in the frequency of S. dentisani in the caries-free group suggests the possibility of requiring minimum levels of this species in the dental biofilm to show an actual protective effect. It must also be considered that this effect might be related to intrinsic factors in children and the intraspecies genetic variability found in every individual. (AU)
Objetivo : Streptococcus mutans é um dos agentes etiológicos associados à cárie devido à sua habilidade de metabolizar carboidratos e resistir a ambientes ácidos. Já o Streptococcus dentisani , apresenta características associadas ao controle da cárie devido à sua capacidade de inibir o crescimento de bactérias cariogênicas. O objetivo deste trabalho foi quantificar os níveis de Streptococcus mutans e Streptococcus dentisani no biofilme dental de crianças em relação à situação de cárie destas. Material e Métodos: Após a identificação das características morfológicas das cepas de referência, foram selecionados do biofilme isolados clínicos compatíveis com essas cepas e realizada a técnica de Reação em Cadeia da Polimerase utilizando primers espécie-específicos. Amostras de biofilme de 25 crianças com cárie e 21 sem cárie foram coletadas para quantificar os níveis de S. mutans e S. dentisani. Resultados: Houve diferenças estatisticamente significativas nos níveis de S. mutans no grupo com cárie e os níveis aumentaram à medida que a gravidade da lesão cariosa aumentou. Por outro lado, foram encontrados níveis mais elevados de S. dentisani no grupo sem cáries, embora não tenham sido encontradas diferenças estatisticamente significativas. Além disso, os níveis de S. dentisani diminuíram à medida que a gravidade da lesão cariosa aumentava. Conclusão: O aumento da frequência de S. dentisani no grupo livre de cárie sugere a possibilidade de exigir níveis mínimos desta espécie no biofilme dental para mostrar um efeito protetor real. Deve-se considerar também que esse efeito pode estar relacionado a fatores intrínsecos nas crianças e à variabilidade genética intraespécie encontrada em cada indivíduo. (AU)
Subject(s)
Humans , Child , Streptococcus mutans , Biofilms , Dental CariesABSTRACT
Purpose: To study the clinical presentation, mycological profile, and risk factors of fungal keratitis (FK) cases presenting at two tertiary?care centers, one each at North (Chandigarh) and Northeast (Assam) India, and to compare the spectrum of fungi recovered from the clinical and environmental samples at both locations. Methods: All patients with suspected FK were enrolled from both the centers between January 2018 and December 2019. Corneal samples were collected and processed as per standard laboratory protocols. Demographic details and clinical and mycological profiles were noted in all patients. Environmental sampling from the soil, air, and the vegetative matter was performed from both locations and neighboring districts. Results: Of the 475 suspected cases, 337 (71%) were diagnosed as FK (median age: 50 years; 77.2% males). The presence of diabetes, hypertension, blurred vision, and corneal discoloration was significantly higher in patients with FK compared to those without FK. Aspergillus sp. (52.1%) and Fusarium sp. (47.61%) were the predominant etiological agents isolated from cases in North and Northeast India, respectively. FK due to melanized fungi was associated with diabetes, trauma with animal tail, and corneal discoloration. A similar spectrum of fungi was seen in environmental and clinical samples in both the regions. Conclusion: The difference in etiological agents of FK and environmental fungal isolates in North and Northeast India highlights the need to identify the ecological niche of potential fungal pathogens. Prospective, multicenter studies, systematic environmental sampling, and the evaluation of the differences in causative agents and clinical presentation of FK from different parts of the country can substantially improve our understanding of its region?specific clinico?epidemiological profile.
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BACKGROUND Leishmania parasites carry a double-stranded RNA virus (Leishmania RNA virus - LRV) that has been divided in LRV1 and LRV2. OBJECTIVES Leishmania (Viannia) braziliensis clinical isolates were assessed in order to determine LRV presence. METHODS Two-round polymerase chain reaction (PCR and nested PCR) was performed to detect LRV1 or LRV2 in L. (V.) braziliensis clinical isolates (n = 12). FINDINGS LRV1 was detected in three clinical isolates which was phylogenetically related to other sequences reported from other American tegumentary leishmaniasis (ATL) endemic areas of Brazil. Patients infected with L. (V.) braziliensis LRV-negative showed only cutaneous lesions while LRV-positive reported different manifestations. MAIN CONCLUSION Data presented here show for the first time that LRV1 is circulating in L. (V.) braziliensis clinical isolates from Rio de Janeiro State in Brazil.
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Strain-resource engineering is often considered as an important infrastructure of microbiology related research and industry. The western developed countries took the lead in establishing the classical microbial resource utilization method, and continuously improved the preservation system, species annotation technology and global sharing mechanism, which realized the expansion and reserve of biological resources since end of the 19th century. The rich and diversified germplasm resources, standard strains and production strains not only have important economic values, but also maintain the advantages of scientific research, bioeconomy (such as antimicrobial agents, vaccines, detection reagent development and standard development, etc.) and national security. Although there has been a lot of progress in related research in recent years, compared with developed countries, there is still a big gap in related fields in China. The investment and top-level design in this area lag far behind the western developed countries, and it is not commensurate with the current level of economic and social development in my country. Drawing lessons from the practice of WFCC and WDCM (World Data Center for Microorganisms, Global microbial data Center, affiliated to WFCC), for the purpose of collecting new clinical species/strains, this paper puts forward some suggestions on the identification, preservation and upload system of isolates.
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Background: Pseudomonas aeruginosa has been highly associated with carbapenem resistance in which carbapenemases has been suggested to be a major contributory factor. Hence the objective of this study was to phenotypically detect KPC-type carbapenemase, metallo-ß-lactamase and OXA-48 carbapenemase production in clinical isolates of P. aeruginosa in Lagos University Teaching Hospital (LUTH), Nigeria Methodology: One hundred and seventy-one P. aeruginosa isolates consecutively recovered from clinical specimens of patients with infections at the Medical Microbiology and Parasitology laboratory of the hospital were identified using MicrobactTM 24E kit. Preliminary screening for carbapenem resistance was determined by the disc diffusion method on Mueller-Hinton agar using single discs of meropenem and imipenem. Phenotypic detection of carbapenemase production among carbapenem-resistant isolates was performed by the combination disc test of meropenem-phenylboronic acid (MRPBO) and meropenem-dipicolinic acid (MRPDP) as recommended by EUCAST 2013 guideline. Results: Out of the 171 P. aeruginosa isolates, 35 (20.5%) were carbapenem non-susceptible (resistant) while carbapenemase production was detected in 27 (77.1%) of these carbapenem resistant isolates, and no enzyme was detected in 8 (22.9%). Of the 27 carbapenemase producing isolates, 22 (81.5%) produced MBL, 1 (3.7%) produced KPC, while 4 (14.8%) produced both KPC and MBL enzymes. Conclusion: This study revealed that carbapenem resistance among P. aeruginosa clinical isolates in our institution is gradually increasing. The mechanism for this rise is associated with carbapenemases, with MBL being the major carbapenemase involved. There is the need to ensure strict compliance with the LUTH infection control guidelines in order to check the rising incidence of infection caused by carbapenem resistant P. aeruginosa
Subject(s)
Pseudomonas aeruginosa , Hospitals, Teaching , Infections , NigeriaABSTRACT
Objective:To explore the resistance of common clinical isolates to chlorhexidine gluconate (CHG) and the clinical characteristics of patients with the infections.Methods:A total of 1 000 isolates from the First Affiliated Hospital of Wenzhou Medical University in 2018 (from January to May) were collected, which included 200 strains each of Escherichia coli ( E. coli), Acinetobacter baumanii ( A. baumanii), Pseudomonas aeruginosa ( P. aeruginosa), Staphylococcus aureus ( S. aureus), and Enterococcus spp.. Minimum inhibitory concentration (MIC) of CHG against 1 000 isolates were determined by the agar dilution method. The correlation between the resistance of isolates and clinical characteristics of infected patients was analyzed. Chi-square test or Fisher exact probability test were used for statistical analysis. Results:A total of 57 CHG resistant strains were detected in 1 000 clinical isolates. These CHG-resistant strains were mainly isolated from sputum and intensive care unit ward, accounting for 49.1%(28/57)and 38.6%(22/57), respectively. The resistance rates of P. aeruginosa, A. baumanii, Enterococcus spp., S. aureus, and E. coli to CHG were 16.0%(32/200), 7.0%(14/200), 3.0%(6/200), 1.5%(3/200) and 1.0%(2/200), respectively. The CHG-resistant rates of P. aeruginosa to ceftazidime, ciprofloxacin, levofloxacin and gentamicin were 53.1%(17/32), 78.1%(25/32), 65.6%(21/32) and 50.0%(16/32), respectively, which were all higher than those of CHG-sensitive P. aeruginosa (25.0%(8/32), 25.0%(8/32), 21.9%(7/32) and 15.6%(5/32), respectively), with statistical significance ( χ2=5.317, 18.080, 12.444 and 8.576, respectively, all P<0.05). The hospital mortality was 22.8%(13/57) in patients infected with CHG-resistant bacteria, which was higher than that in patients infected with CHG-sensitive bacteria ((7.0%(4/57); Fisher exact probability test, P=0.018)). CHG-resistant group had a higher history of CHG exposure and antimicrobial treatment (61.4%(35/57) and 70.2%(40/57), respectively), which were both higher than those with CHG-susceptible isolates (17.5%(10/57) and 47.4%(27/57), respectively), the differences were both statistically significant ( χ2=22.947 and 6.118, respectively, both P<0.05). In addition, the multi-drug resistance rate of CHG-resistant strains was 54.4%(31/57), which was higher than that of CHG-susceptible strains (35.1%(20/57)), the difference was statistically significant ( χ2=4.293, P=0.039). Conclusions:CHG resistant strains have higher antimicrobial resistance. Hospital mortality in patients infected with CHG-resistant bacteria is higher than patients infected with CHG-sensitive bacteria. The important risk factors are CHG exposure and antimicrobial therapy.
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Objectives: Staphylococcus aureus(S.aureus) is regarded as an important aetiological agent of various human infections. Fluoroquinolonesare routinely used in the chemotherapeutic management of these infections; nonetheless, in recent years, a growing rate of resistance to these drugs has been reported worldwide. The aims of this study were to isolate and discover the prevalence of plasmid-mediated (qnrA, qnrB, and qnrS) genes among the quinolone-resistant clinical S. aureusisolates in Bayelsa State, Nigeria.Methods: A total of 25 (31.25%) clinical isolates of S. aureuswere collected from hospitalized patients. The bacterial isolates were identified through standard laboratory protocols and further confirmed using the API Staph system (bioMérieux, France) test strips. The antimicrobial susceptibility and minimum inhibitory concentration (MIC) were determined by the standard disk diffusionand serial dilutions methods respectively. Polymerase chain reaction (PCR) was used for detecting qnrA, qnrB, and qnrSgenes.Results: Of the 25 S. aureus isolates, 19(76.00%) were resistant to ampicillin-cloxacillin, while 14 (56.00%) each were resistantto norfloxacin and Amoxicillin, 13 (52.00%) each to gentamicin and erythromycin, 11 (44.00%) were resistant to streptomycin, rifampicin and ciprofloxacin, respectively. The resistance pattern among the isolates to chloramphenicol and levofloxacin were 10 (40.00%) and 7 (28.00%) respectively. All the eleven ciprofloxacin resistant were high-level (1000 μg/mL) resistance isolates and only one (9.00%) of these isolates was positive for the qnrBgene.Conclusion: The study results were indicative of the presence of low frequency of qnrgenes among the clinical isolates of S. aureusin Yenagoa, indicating that other mechanisms are employed in resisting to these fluoroquinolones. This, however, emphasizes the need for establishing discreet policies associated with infection-control measures in hospital settings
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Objectives: Candida albicans as important opportunistic dimorphic fungi can cause the life threatening infections in humans. In this study, we evaluated the anticandidal activities of six samples of Pelargonium graveolens essential oils against 31 clinical isolates of C.albicans. Materials and methods: The anti-candidal activity was performed by disc diffusion and micro-broth dilution assays. The chemical compositions of essential oils were analyzed by Gas Chromatography (GC) apparatus. Results: P. graveolens essential oil samples with citronellol (7.7-43.7%) and geraniol (19.3-48.5%) showed the same anti-candidal activity in two different methods. There is no significant difference between the inhibition zone diameters (19.3-24.1 mm), and the MIC and MFC values (1.06-1.48 and 1.5-1.72 µl/ml) of essential oil samples with different percent of citronellol and geraniol. Conclusion: Therefore, P.graveolens essential oils can be used as anti-candidal agent for further studies.
Objetivos: Candida albicans es un importante hongo dimórfico oportunista que puede llegar a amenazar la vida de pacientes con inmunosupresión. En este estudio se evaluaron las actividades anti-Candida de seis muestras de aceites esenciales de Pelargonium graveolens contra 31 aislamientos clínicos de C. albicans. Materiales y métodos: La actividad anti-Candida se realizó por difusión en disco y ensayos de dilución micro-caldo. La composición química de los aceites esenciales se analizó mediante cromatografía de gases. Resultados: Las muestras de aceite esencial de P. graveolens con citronelol (7,7 a 43,7%) y geraniol (19,3 a 48,5%) mostraron la actividad anti-Candida en dos métodos diferentes. No hubo ninguna diferencia significativa entre los diámetros de la zona de inhibición (19,3-24,1 mm), y valores de MFC (1,06 a 1,48 y de 1,5 a 1,72 l / ml) de muestras de aceites esenciales con diferentes porcentajes de citronelol y geraniol. Conclusión: Los aceites esenciales de P.graveolens se pueden utilizar como agentes anti-Candida para estudios adicionales.
Subject(s)
Humans , Candida albicans , Oils, Volatile , Pelargonium , Patient Isolation , Plants , Immunosuppression Therapy/nursing , Geranium , Cymbopogon , FungiABSTRACT
Objective To analyze the growth characteristics of the clinical isolates of Aspergillus compared to standard strains in vitro.Methods The sabourauds agar medium (SDA),yeast extract medium(YG) and potato dextrose agar medium (PDA) were used to test two clinical isolates and one standard strain.The strains were incubated at 29 ℃C for 96 hours.In liquid medium,the optical density (OD) values at 0 hour,4,8,12,24,36,48,60,72 and 96 hours after culture were recorded to generate growth curves for each strain and culture medium.Meanwhile,on solid medium,the features of colony morphology were recorded.Results In liquid medium,the growth curves were not significantly different between clinical isolates and standard strain in PDA medium (all at P＜0.05),while the differences were obvious in SDA medium and YG medium (P＜0.05).The clinical isolates showed shorter lag phase and higher growth rate than standard strain.On solid medium,all strains appeared the best growth state on PDA medium and the poorest state on SDA medium.Color change time was later on YG medium than that on the other medium.The clinical isolates performed better on the aspects of colony sizes and color change than standard strain when growed on the same medium,especially on SDA medium.Conclusions Compared with standard strain,the clinical isolates of Aspergillus have higher adaptive capacity to poor nutrition condition.
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Haemophilus parasuis is the etiological agent of Glässer's disease (GD), an ubiquitous infection of swine characterized by systemic fibrinous polyserositis, polyarthritis and meningitis. Intensive use of antimicrobial agents in swine husbandries during the last years triggered the development of antibiotic resistances in bacterial pathogens. Thus, regular susceptibility testing is crucial to ensure efficacy of different antimicrobial agents to this porcine pathogen. In this study, 50 clinical isolates from South Brazilian pig herds were characterized and analyzed for their susceptibility to commonly used antibiotic. The identification and typing of clinical isolates was carried out by a modified indirect hemagglutination assay combined with a multiplex PCR. The susceptibility of each isolate was analyzed by broth microdilution method against a panel of 21 antimicrobial compounds. We found that field isolates are highly resistance to gentamycin, bacitracin, lincomycin and tiamulin, but sensitive to ampicillin, clindamycin, neomycin, penicillin, danofloxacin and enrofloxacin. Furthermore, an individual susceptibility analysis indicated that enrofloxacin is effective to treat clinical isolates with the exception of those classified as serovar 1. The results presented here firstly demonstrate the susceptibility of Brazilian clinical isolates of H. parasuis to antimicrobials widely used by swine veterinary practitioners and strengthen the need to perform susceptibility test prior to antibiotic therapy during GD outbreaks. In addition, because only six antimicrobial drugs (28.6%) were found effective against field isolates, a continuous surveillance of the susceptibility profile should be of major concern to the swine industry.(AU)
Haemophilus parasuis é o agente etiológico da doença de Glässer (GD), um processo infeccioso que acomete suínos e que se caracteriza por poliserosites fibrinosas sistêmicas, poliartrites e meningites. O uso intensivo de agentes antimicrobianos na produção de suínos, durante os últimos anos, tem disparado a seleção de cepas bacterianas resistentes a antibióticos. Desta maneira, a avaliação rotineira de susceptibilidade torna-se crucial para assegurar a correta seleção de um antimicrobiano eficaz contra este patógeno. Neste estudo, analisou-se a susceptibilidade antimicrobiana de 50 isolados clínicos de H. parasuis procedentes de granjas localizadas na região sul do Brasil. A identificação e tipificação dos isolados clínicos foi realizada através de uma PCR multiplex combinada com o teste de hemaglutinação indireta modificada. A susceptibilidade de cada isolado foi analisada pelo método de microdiluição em caldo utilizando-se um painel composto por 21 agentes antimicrobianos. Os resultados deste estudo indicam que as cepas clínicas de H. parasuis apresentam alta resistência à gentamicina, bacitracina, lincomicina e tiamulina, no entanto, são susceptíveis a ampicilina, clindamicina, neomicina, penicilina, enrofloxacina e danofloxacina. A análise de susceptibilidade realizada dentro de cada grupo de cepas de um mesmo sorovar indicou que a enrofloxacina é o antibiótico mais efetivo para tratar todos isolados clínicos com exceção daqueles pertencentes ao sorovar 1. Em termos gerais, neste trabalho, demonstra-se o perfil de susceptibilidade de isolados clínicos de H. parasuis aos antimicrobianos comumente utilizados pelos médicos veterinários especialistas em suínos, e reforça-se a necessidade da realização de testes de susceptibilidade antes do início da terapia com antibióticos durante surtos de DG. Além disso, como somente seis antimicrobianos (28.6%) foram efetivos contra os isolados clínicos, uma vigilância contínua do perfil de susceptibilidade aos antimicrobianos deve ser de grande preocupação para a indústria de suínos.(AU)
Subject(s)
Animals , Swine Diseases/drug therapy , Drug Resistance, Microbial , Drug Resistance, Bacterial/drug effects , Haemophilus parasuis/drug effects , Haemophilus Infections/veterinary , Sus scrofaABSTRACT
Coagulase negative Staphylococci (CoNS) are increasingly being recognized as significant nosocomial pathogens, partly due to the growing appreciation of this group of organisms as opportunistic pathogens or due to increase in the use of transient or permanent medical devices in seriously ill and immunocompromised patients. Aims and Objectives 1) Isolation of CoNS from exudates and body fluids. 2) Biochemical characterization of CoNS. 3) Antibiotic susceptibility pattern of CoNS. Method 180CoNS isolated from various exudates and body fluids such as pus, wound swabs, endotracheal secretions, sputum, branchialaspitate, and central lining tube were collected. All the CoNS isolates were processed in the Microbiology Laboratory and identified by colony morphology, gram staining, catalase, slide, tube coagulase test, anaerobic acid from mannitol, and deoxyribonuclease. Bacitracin (0.04 U) and furazolidone (100 μg) susceptibilities were done to exclude Micrococcus and Stomatococcus spp. The following biochemical tests were done for the speciation of the CoNS: urease test, phosphatase test, polymyxin B disc test, novobiocin disk test, ornithine decorboxylase test, mannitol to acid, Voges-Proskauertest, mannose fermentation, trehalose fermentation and antibiotic susceptibility testing. Result Out of 180 isolates, 78 are Staphylococcus epidermidis (43.3%), 63 are Staphylococcus hemolyticus (35%), 21 are Staphylococcus hominis (11.6%), and 18 are Staphylococcus lugdunensis (10.0%). Maximum number of CoNS were isolated from pus specimens (58.33%), followed by wound swabs (18.33%). A total of 164out of 180 strains were negative for both bound and free coagulase. A total of 60 strains were bound coagulase slow positive and free coagulase negative. S. epidermidis was the most frequent isolate and 68 S. epidermidis isolates were identified if ornithine decorboxylase was considered positive, while negative 10 S. epidermidis isolates required inclusion of trehalose and mannitol for speciation. Antibiotic susceptibility testing showed maximum resistance to penicillin (78.3) followed by chloramphenicol (41.6%). No resistance to vancomycin was seen. Conclusion: The study revealed S. epidermidis is the predominant CoNS from endotracheal secretions and also pus samples. S. hemolyticus was isolated from pus and central lining tubes, S. hominis and S. lugdunensis were isolated mainly from wound swabs. The present study suggests if coagulase-ve Staphylococci are repeatedly isolated from patients with infection they should be taken seriously and ABST done on these isolates for proper diagnosis and treatment especially in nosocomial infections.
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Antimicrobial resistance is a subject of great concern in public health and also in the designing of strategies for current therapeutic protocols all over the world. Plants used for traditional medicine contain a wide range of substances which can be used to treat various infectious diseases. Hence, antibacterial activities of aqueous extracts of 10 plant species were studied against 25 multidrug resistant (MDR) clinical isolates using the agar well diffusion method. The most resistant organisms were Acinetobacter baumanii (A. baumanii) (resistant to 16 different antibiotics), Enterococcus faecium (E. faecium) (resistant to 15 different antibiotics), Pseudomonas aeruginosa (P. aeruginosa) (resistant to 15 antibiotics), Gemella morbillorum (G. morbillorum) (resistant to 14 different antibiotics), Enterobacter cloacae (E. cloacae) (resistant to 13 different antibiotics) respectively. Among the tested plant extracts, only extracts of Allium cepa, Allium sativum, Foeniculum vulgare, Matricaria chmomilla, Salvia offcinalis and Thymus Vulgaris showed strong antibacterial activity against MDR isolates with inhibition zones ranging from 8.33 to 26 mm. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the most active plant extracts; Allium cepa and Foeniculum vulgare were ranged from 0.062 to 0.25 mg/ml and 0.031 to 0.125 mg/ml, respectively. Foeniculum vulgare extract was bactericidal for all bacteria while Allium cepa extract was bacteriostatic. Hence, the discovered compounds from these plants can use as templates for the development of new antibacterial agents.
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Objective: Continuous emergence of resistance among Pseudomonas aeruginosa strains to common antimicrobial drugs have been documented world-wide. This study investigated the recent trend of antimicrobial resistance patterns of P. aeruginosa among the patients in mid & far western region of Nepal. Materials and Methods: The study was conducted on 917 patients with suspected P. aeruginosa infections, attending outpatient and inpatient departments of Nepalgunj Medical College and teaching Hospital, Banke, Nepal from September 2011 to January 2014. Specimens were collected from pus/wound, sputum, urine, tracheal aspirates, central venous catheter tip, broncho-alveolar lavage fluid, catheters and vaginal swabs and processed for isolation and identification of P. aeruginosa following the standard microbiological methods. The disc diffusion test was used to determined antimicrobial resistance patterns of the recovered isolates at the central Laboratory of Microbiology. Results: One hundred ninety four isolates were identified as P. aeruginosa. Resistance to Chloramphenicol (74.23%), Ceftriaxone (69.56%), Cefepime (57.22%), Cefoperazone-Salbactum (54.12%) and Co-trimoxazole (53.02%) was observed. All the isolates were susceptible to Imipenem. 48 (24.74%) of P. aeruginosa isolates were multi-drug resistant to >3 classes of antibiotics. Among 194 isolates, 88 (45.36%) were from the patients of 21-40 years age group, which was statistically significant (P<0.05) compared to the other age groups. Conclusions: The study revealed the presence of drug resistant strains of P. aeruginosa in Nepal. High levels of antibiotic resistance of many of the isolates might be due to antibiotic abuse. Therefore, we recommend judicious use of antibiotics by the physicians to curb the increasing multi-drug resistance of P. aeruginosa strains in Nepal.
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Acinctobacter species are common non fermentative gram negative bacilli isolated in clinical laboratory most frequently encountered species. Acinetobacter resistance is develop due to acquired resistance. Because of frequent multidrug resistance isolates carbapenems have become important for treating resistant strains. There is a need for rapid screening & detection of MBL in Acinetobacter to modify the treatment. The present study was aim to determine the resistance of A.baumanii complese to various classes of drugs and to carbapenems and MBL production. Samples such as urine, blood, sputum, pus & body fluids. All samples were processed as per CLSI guidelines. Meropenem resistant strains were screened for carbapenemase and MBL production. Out of 92 Acinetobacter 85 (92.39%) were Acinetobacter baumanii. More than 80% resistance is seen in 3rd generation Cephalosporins. Out of 21 meropenem resistant strains 14 were carbapenemase positive and 3 were MBL producers. Our study shows raising trend of multidrug resistance and carbapenem. This will help in early detection and better treatment modalities. Abbreviations: MRSA–Methicillin resistant Staphylococcus aureus, ESBL – Extended sputum β - lactamases GNB – Gram negative bacilli, MDR – Multi drug resistance
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Objective: To study the prevalence of extended-spectrum β-lactamases (ESBLs) among 663 clinical isolates obtained from various parts of India and to study the occurrence of different variants of ESBLs among these isolates. Methods: Phenotypic characterization and susceptibility studies were performed according to the methods described in Clinical and Laboratory Standards Institute guidelines. The occurrence of ESBL variants was analyzed with PCR using the previously reported primers. Results: Among the six hundred sixty three isolates, the identified isolates were Acinetobacter baumannii (72), Escherichia coli (218), Klebsiella pneumoniae (30), Klebsiella oxytoca (63), Pseudomonas aeruginosa (264) and Staphylococcus aureus (16). PCR results revealed that approximately 89.0% of Pseudomonas aeruginosa isolates were positive for ESBL followed by Escherichia coli (85.3%), Klebsiella pneumoniae (76.6%), Klebsiella oxytoca (73.0%), Acinetobacter baumannii (72.2%) and Staphylococcus aureus (31.2%). The overall prevalence of ESBL was 82.5%. The presence of TEM type ESBLs were the predominant (in 186 isolates), followed by SHV (138), OXA (92), CTX-M (65), AmpC (33), KPC (28) and blaZ (5). Of the drugs involved in the study, CSE1034 was found to be the most efficacious against all of ESBL positive clinical isolates showing susceptibility approximately 95.7% with minimal inhibitory concentration values between 0.125 and 8.000 μg/mL for all strains tested. The susceptibilities of penems (meropenem and imipenem and cilastatin) ranged between 83% and 93% for all the isolates. The susceptibilities of other drugs like piperacillin and tazobactam, amoxicillin and clavulanic acid, cefoperazone and sulbactam were <45% for all the isolates. Conclusions: Results of the present study indicated that majority of the isolates was susceptible to CSE1034 and it could be a potent antibacterial agent for the treatment of severe bacterial infections caused by such organisms.
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OBJECTIVE@#To study the prevalence of extended-spectrum β-lactamases (ESBLs) among 663 clinical isolates obtained from various parts of India and to study the occurrence of different variants of ESBLs among these isolates.@*METHODS@#Phenotypic characterization and susceptibility studies were performed according to the methods described in Clinical and Laboratory Standards Institute guidelines. The occurrence of ESBL variants was analyzed with PCR using the previously reported primers.@*RESULTS@#Among the six hundred sixty three isolates, the identified isolates were Acinetobacter baumannii (72), Escherichia coli (218), Klebsiella pneumoniae (30), Klebsiella oxytoca (63), Pseudomonas aeruginosa (264) and Staphylococcus aureus (16). PCR results revealed that approximately 89.0% of Pseudomonas aeruginosa isolates were positive for ESBL followed by Escherichia coli (85.3%), Klebsiella pneumoniae (76.6%), Klebsiella oxytoca (73.0%), Acinetobacter baumannii (72.2%) and Staphylococcus aureus (31.2%). The overall prevalence of ESBL was 82.5%. The presence of TEM type ESBLs were the predominant (in 186 isolates), followed by SHV (138), OXA (92), CTX-M (65), AmpC (33), KPC (28) and blaZ (5). Of the drugs involved in the study, CSE1034 was found to be the most efficacious against all of ESBL positive clinical isolates showing susceptibility approximately 95.7% with minimal inhibitory concentration values between 0.125 and 8.000 μg/mL for all strains tested. The susceptibilities of penems (meropenem and imipenem and cilastatin) ranged between 83% and 93% for all the isolates. The susceptibilities of other drugs like piperacillin and tazobactam, amoxicillin and clavulanic acid, cefoperazone and sulbactam were <45% for all the isolates.@*CONCLUSIONS@#Results of the present study indicated that majority of the isolates was susceptible to CSE1034 and it could be a potent antibacterial agent for the treatment of severe bacterial infections caused by such organisms.
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Objective To explore the effects of intracellular calcium concentration ([Ca2 + ]i )and signal transducers and activators of transcription 3 (STAT3 )signaling pathway on the invasion of Vibrio vuknificus (Vv )clinical isolates B2 into dendritic cells (DC).Methods The co-culture model of Vv B2 and DC 2.4 was constructed.Apoptosis and necrosis rates in different invasion phases were detected by flow cytometry.The calcium fluorescence probe Fluo-8-AM was used to detect the change of [Ca2 + ]i ,and Western blot and immunofluorescent techniques were used to explore the relative molecular expressions and intracellular distributions of STAT3 and phosphorylation STAT3 [p-STAT3 (705 )].Data were analyzed by t-test.Results After co-culture ofVv B2 and DC 2.4,the apoptosis rates of 1 ,2,3 and 4 h were (13.10±4.72)%,(30.10±3.52)%,(46.20±15 .61)% and(31 .00 ±19.10)%,respectively.The differences were statistical significant between Vv standard strain (1 .1758)and Vv B2 (t=4.30,22.33, 4.30 and 4.30,respectively;P =0.040,0.002,0.040 and 0.040,respectively).The necrosis rates of 1 , 2,3 and 4 h in co-culture of Vv B2 and DC 2.4 were(19.70 ±3.50 )%,(39.20±4.60 )%,(40.90 ± 13.80)% and (62.10 ± 8.20 )%,respectively.The differences were statistical significant between Vv 1 .1758 andVv B2 (t=9.93,14.09,4.30 and 14.09,respectively;P =0.010,0.005 ,0.049 and 0.005 , respectively).Compared to Vv 1 .1758,Vv B2 induced more apparent cell apoptosis and necrosis within the same time.By fluorescence microscope,intensity of calcium was enhanced with the rising of apoptosis. Although the total expression of STAT3 increased,the relative molecular expression of p-STAT3 (705 ) decreased.There was no significant difference in its distribution in cells compared to the blank group. Conclusion The rapid apoptosis and necrosis of DC during Vv B2 invasion into DC may be caused by increasing [Ca2 + ]i and inhibiting phosphorylation of p-STAT3 (705)simultaneously.
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Antimicrobial resistance is a subject of great concern in public health and also in the designing of strategies for current therapeutic protocols all over the world. Plants used for traditional medicine contain a wide range of substances which can be used to treat various infectious diseases. Hence, antibacterial activities of aqueous extracts of 10 plant species were studied against 25 multidrug resistant (MDR) clinical isolates using the agar well diffusion method. The most resistant organisms were Acinetobacter baumanii (A. baumanii) (resistant to 16 different antibiotics), Enterococcus faecium (E. faecium) (resistant to 15 different antibiotics), Pseudomonas aeruginosa (P. aeruginosa) (resistant to 15 antibiotics), Gemella morbillorum (G. morbillorum) (resistant to 14 different antibiotics), Enterobacter cloacae (E. cloacae) (resistant to 13 different antibiotics) respectively. Among the tested plant extracts, only extracts of Allium cepa, Allium sativum, Foeniculum vulgare, Matricaria chmomilla, Salvia offcinalis and Thymus Vulgaris showed strong antibacterial activity against MDR isolates with inhibition zones ranging from 8.33 to 26 mm. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the most active plant extracts; Allium cepa and Foeniculum vulgare were ranged from 0.062 to 0.25 mg/ml and 0.031 to 0.125 mg/ml, respectively. Foeniculum vulgare extract was bactericidal for all bacteria while Allium cepa extract was bacteriostatic. Hence, the discovered compounds from these plants can use as templates for the development of new antibacterial agents.
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Introducción. A escala mundial, se ha observado la aparición de cepas de Pseudomonas aeruginosa multirresistentes durante las últimas décadas. Este patógeno oportunista produce mecanismos de resistencia a diversos antibióticos. La resistencia a carbapenémicos en cepas de P. aeruginosa se ha asociado con la formación de biopelículas bacterianas, favorecidas por la presencia de exopolisacáridos (EPS) embebidos en una matriz extracelular y por la producción de los pili tipo IV (T4P). El objetivo de este trabajo fue evaluar la formación de biopelículas en cepas clínicas aisladas en el Hospital Infantil de México Federico Gómez de P. aeruginosa resistentes a carbapenémicos, a través de la cuantificación de los expolisacáridos totales-reductores y su asociación con la expresión fenotípica de los T4P. Métodos. Se realizaron ensayos de susceptibilidad antibiótica por el método de Kirby-Bauer en 92 cepas clínicas de P. aeruginosa. Asimismo, se determinó la concentración mínima inhibitoria (MIC) para imipenem (IMP) y meropenem (MEM) por el método de dilución seriada en placas con agar con un replicador de Steers. La producción de metalo-β-lactamasas fue determinada mediante la técnica de difusión en disco y de sinergismo. Las biopelículas fueron realizadas en cepas clínicas de P. aeruginosa resistentes a carbapenémicos, a través de la cuantificación de cristal violeta, azúcares totales (antrona) y azúcares reductores (DNS), además de la expresión fenotípica de los T4P por la actividad de twitching motility . La diversidad genética de las cepas formadoras de biopelículas y productoras de azúcares reductores fue evaluada mediante la técnica de electroforesis de campos pulsados (PFGE). Resultados. El 30.4% (28/92) de las cepas de P. aeruginosa de origen pediátrico fueron recuperadas de la sala de cirugía y el 50% (46/92) de muestras de orina. Los resultados por Kirby-bauer mostraron que más de 50% de la cepas de P. aeruginosa fueron resistentes a 12 diferentes antibióticos. La MIC a los carbapenémicos fue de 64 µg/ml, con 43.1% (25/58) para MEM y 56.8% (33/58) para IMP. Así mismo, la producción de metalo-β-lactamasas fue observada en 43% (25/58) para MEM, 2% (1/58) para IMP y 12% (7/58) para ambas. Los análisis mostraron que 82% (48/58) de las cepas de P. aeruginosa resistentes a carbapenémicos fueron altas formadoras de biopelículas. De éstas, 46.5% (27/58) mostraron concentraciones de EPS totales de 2000 a 6000 µg/ml y 27.5% (16/58) mostraron concentraciones de EPS reductores de 316 a 1108 µg/ml; además, 75% (44/58) de estas cepas mostraron actividad fenotípica de twitching motility . Conclusiones. La detección de azúcares totales, azúcares reductores y el fenómeno de twitching motility son factores que favorecen el desarrollo de las biopelículas en cepas clínicas de P. aeruginosa resistentes a carbapenémicos. Los datos sugieren que estos factores están involucrados en la formación de biopelículas que confieren a la bacteria la capacidad para sobrevivir, persistir y colonizar a su hospedero.
Background. In recent years, the worldwide emergence of multidrug-resistant strains of Pseudomonas aeruginosa has been observed. This opportunistic pathogen produces mechanisms of resistance to several antibiotics. The resistance to carbapenems in P. aeruginosa strains has been associated with bacterial biofilm formation, favored by the presence of exopolysaccharides (EPS) embedded in an extracellular matrix and to the production of type IV pili (T4P). We undertook this study to assess biofilm formation in clinical strains of P. aeruginosa resistant to carbapenems isolated at the Hospital Infantil de Mexico Federico Gomez (HIMFG) through quantification of total-reducing EPS and its association with the phenotypic expression of T4P. Methods. Antibiotic susceptibility tests were performed using the Kirby-Bauer method in 92 clinical isolates of P. aeruginosa ; likewise, the minimum inhibitory concentration (MIC) was determined for imipenem (IMP) and meropenem (MEM) by the serial dilution method in agar plates with a Steers replicator. Production of metallo-β-lactamase (MBL) was determined by the disk diffusion method and synergism. Biofilm formation was performed in clinical isolates of P. aeruginosa resistant to carbapenems through the quantification of crystal violet, total sugar (anthrone), and reducing sugar (DNS), in addition to the phenotypic expression of T4P activity of twitching motility. The genetic diversity of strains forming biofilm and producing reducing sugars was evaluated by pulsed-field gel electrophoresis (PFGE). Results. There were 30.4% (28/92) of P. aeruginosa strains of pediatric origin and 50% (46/92) of urine samples that were recovered from the operating room. The results using the Kirby-Bauer method showed that >50% of P. aeruginosa strains were resistant to 12 different antibiotics. The MIC to carbapenems was 64 µg/ml, with 43.1% (25/58) for MEM and 56.8% (33/58) for IMP. Likewise, MBL production was observed in 43% (25/58) for MEM, 2% (1/58) for IMP, and 12% (7/58) for both. Qualitative and quantitative analysis showed that 82% (48/58) of P. aeruginosa strains resistant to carbapenems were high biofilm formers using the crystal violet method. Of the high biofilm forming strains, 46.5% (27/58) showed concentrations of total EPS between 2000 and 6000 µg/ml and 27.5% (16/58) showed concentrations of reducing EPS between 316 and 1108 µg/ml. In addition, 75% (44/58) of these strains showed phenotypic activity of twitching motility. Conclusions. Detection of total sugars, reducing sugars, and the phenomenon of twitching motility are factors that promote the development of biofilms in clinical strains of P. aeruginosa resistant to MBL producers to carbapenems. Our data suggest that these factors are involved in biofilm formation, which confer bacterium with the ability to survive, persist, and colonize its host.