International Medical Publisher Journals (iMedPub)
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Prevalence of Carbapenemase-Producing Enterobacteriaceae in a University Hospital in Rabat, Morocco: A 19-Months Prospective Study.
Get PDFObjectives: This study aims to assess the prevalence of clinical isolates of enterobacteriaceae with carbapenem resistance as a result of carbapenemase production, and to characterize the types of enzymes produced. Methods: All non-duplicate enterobacteriaceae (Klebsiella spp, Enterobacter spp and E. coli) clinical isolates collected over 19 months (i.e., in the period from May 2009 through December 2010) were included in the study. The modified Hodge test was performed on strains showing reduced ertapenem susceptibility. Isolates that tested positive were sent to the French reference center on emerging resistance for molecular characterization and clone determination. Results: A total of 463 strains were investigated: E. coli 63.9%, Klebsiella spp 27.9% and Enterobacter spp 8.2%. Carbapenemase production occurred in 13 isolates (2.8%). Ten strains produced class D carbapenemases (OXA-48). These were 6 K. pneumoniae, 1 K. oxytoca and 3 E. cloacae. New Delhi metallo-β-lactamase-1 (NDM-1) metallo enzymes were produced by three K. pneumoniae strains. Conclusion: A source of concern for Morocco can be found in both the high prevalence of carbapenemase producing Klebsiella and Enterobacter clinical isolates and detection of NDM-1 carbapenemases. This requires setting up an emerging resistance monitoring and surveillance scheme at national level
Imipenem/cilastatin versus Meropenem on Fever Defervescence in Septic Febrile Patient: A Comparative Prospective Study
Get PDFObjective: Meropenem efficacy and tolerability was reported to measure up toimipenem/cilastatin, though some data reported that it may be more efficient incertain clinical and bacteriological settings. Our aim here is to demonstrate anypossible difference between the two carbapenems in major septic clinical scenarios.Fever defervescence was selected as a clinical primary “broad†parameter to comparethe effectiveness of imipenem/cilastatin and meropenem on fever defervescencein febrile septic patients.Methods: A prospective multicenter, observational, comparative open label study.The study was conducted in three hospitals between February – September 2009 inAmman-Jordan. Data were collected for patients whom were started on imipenem/cilastatin or meropenem; the study team did not contribute to the antibacterialselection for patients.Results: Seventy patients were evaluated, thirty-two imipenem/cilastatin and thirty-eight meropenem treated patients. Age mean was 60 and 57.6 years for Imipenem/cilastatin and meropenem respectively. The APACHE II score was similar, mean14.4 for both study arms. There was no significant difference in rates of clinicaldiagnoses for both study arms; ventilator-associated pneumonia (VAP), urinary tractinfection (UTI), intra-abdominal infections (IAI), blood stream infection (BSI) or forothers sources. Additional anti-gram negative agents were administered in 10 and9 patients, added anti-MRSA agents in 11 and 12 patients, and antifungal agentsin 3 and 1 patient in imipenem/cilastatin and meropenem treated patients respectively.There was no significant difference between the mean temperatures (38,60C for both), antimicrobial utilization days (8.33 versus 6.67), mean days for feverdefervescence (3.31 versus 2.37, p = 0.36, 95% C.I. (-1.09 - 2.98) for imipenem/cilastatin and meropenem treated patients respectively, mortality was the same.Conclusion: There is no evidence to support the notion that there is clinical differencein fever defervescence between Imipenem/cilastatin and meropenem inthis evaluated group
Antimicrobial tolerance changes in biocide-passaged biofilm cultures of Pseudomonas aeruginosa PAO1
Get PDFThe aim of this study was to develop a novel process for the passaging of biofilms of Pseudomonas aeruginosa towards tolerance to a group of selected antimicrobial agents (biocides). The combination of both a traditional passage approach coupled with a suitable biofilm model, for the production of large numbers of adherent cells, yielded evidence of a development of phenotypic tolerance in Ps. aeruginosa towards selected biocides (zinc pyrithione (ZnPT), sodium pyrithione (NaPT), Cetrimide & Benzisothiazolone (BIT)). The results indicate a step-wise increase in minimal inhibitory concentration (MIC) over a series of ten consecutive passages in the presence of increasing concentrations of biocide. Scanning electron microscopy revealed a complex internal structure to the biofilms grown using this model. Results indicate that it is possible to passage cultures of Ps. aeruginosa towards phenotypic tolerance to selected antimicrobial agents. Results also indicate that such tolerance is partially reversible and that some residual tolerance remains in the absence of biocide. Thus, indicating that the tolerance is partially due to phenotypic changes within biofilm cells. This study describes a novel technique for the induction of phenotypic tolerance towards antimicrobial agents in biofilm situations. The model used here may be adapted to other areas of biofilm work, where clonal selection of phenotypic traits may be desirable
Evaluation of the combination of N-acetylcysteine and or sodium salicylate with ciprofloxacin on bacterial adhesion and biofilm formation on urinary catheters
Get PDFAbstract The aim of this study was to evaluate the effect of ciprofloxacin (CIP), N-acetylcysteine (NAC) and salicylate (SAL) alone and in combination on biofilm production and pre-formed mature biofilms on microtiter plates and urinary tract catheters. Ciprofloxacin at MIC, 1/2MIC, 1/4MIC and 1/8MIC inhibited biofilm production on microtiter plates by 74.36%, 69.55%, 52.41% and 42.37%, respectively and disrupted the pre-formed biofilms by 53.77%, 47.72%, 42.13% and 34.78%, respectively. Ciprofloxacin also inhibited the biofilm production on catheter segments by 67.35% and 55.22% in presence of MIC and 1/4MIC, respectively and disrupted the pre-formed biofilms by 65.83% in presence of MIC and 51.55% in presence of 1/4MIC. NAC and SAL each alone inhibited biofilm production by up to 71% and 68% on microtiter plates and by up to 62% and 68% on catheter segments, respectively and disrupted pre-formed biofilms by up to 67% and 62% from microtiter plates and by up to 61% and 62% from catheter segments, respectively. Ciprofloxacin / N-acetylcysteine showed higher inhibitory effect on biofilm production and higher disruptive effect on the pre-formed biofilms than Ciprofloxacin / Salicylate. When salicylate was added to the Ciprofloxacin / N-acetylcysteine combination it enhanced the biofilm inhibition to become up to 99% and the disruptive effect became up to 98%. Key words:Â biofilm - catheter - microtiter plates - non-antibiotics - resistance. Abbreviations used: CIP, ciprofloxacin; COX, cyclo-oxygenase; MBC, minimum bactericidal concentration; MIC, minimum inhibitory concentration; NAC, N-acetylcysteine; SAL, salicylate; SI, slime index
Epidemiology Features of Acinetobacter baumannii Colonizing Respiratory Tracts of ICU Patients
Get PDFBackground: A. baumannii is becoming a common opportunistic and nosocomialpathogen in ICUs worldwide. Few studies have investigated the epidemiology of A.baumannii isolates colonizing the respiratory tract of hospitalized patients in ICUs.Methods: A total of 93 patients admitted to various intensive care unites (ICUs)over a period of 10-month at the Jordan University Hospital (JUH) were investigatedfor colonizing their respiratory tract with A. baumannii. Risk factors for respiratorycolonization with A. baumannii were determined. All A. baumannii isolateswere examined for their antimicrobial susceptibility pattern, presence of specificβ-lactamase genes and common genotypes using enterobacterial repetitive intergenicconsensus sequences (ERICs) and PCR.Results: Two third of hospitalized patients (63/93; 67.7 %) have their respiratorytract colonized with A. baumannii, and significant risk factors associated withcolonization were longer ICU stay, use of mechanical ventilators and antibiotictreatment with carbapenems. All A. baumannii isolates were multidrug resistant(MRAB) and possessed blaOXA-51-like gene; in addition, 73% and 19% of theisolates harbored blaOXA-23-like and blaOXA-24-like genes, respectively. All isolateswere negative for MBL-encoding gene (blaIMP-1) and only two isolates (3%)harbored (blaVIM-2) gene. The genetic similarity of A. baumannii isolates usingERICs-PCR and constructed dendrogram showed 2 major genotype clusters ofgenetically related isolates.Conclusion: This study shows that few genotypes of MRAB are often colonizingthe respiratory tract of hospitalized patients in ICUs, and colonization was rarelyassociated with blood sepsis and mortality
Emergence of Klebsiella pneumoniae Carbapenemase (blaKPC-2) in members of the Enterobacteriaceae family in Palestine
Get PDFAbstract Background: The global spread of carbapenem resistant Enterobacteriaceae (CRE) has limited the physicians’ antimicrobial treatment options of infected patients. CRE’s which carry the Klebsiella pneumonia Carbapenemase (blaKPC) resistance mechanism have been rapidly spreading in many parts of the world, and have been responsible for high patients’ morbidity and mortality. Methods: Two protocols recommended by the Center for Disease Control and Prevention (CDC) were followed to detect CRE’s in Palestine. In addition, the antimicrobial sensitivity patterns for several antibiotic classes were determined for the isolated CRE’s by the disc diffusion method according to the clinical and laboratory standard institute (CLSI) M100-S22 guidelines. The Minimal Inhibitory Concentrations (MICs) of the carbapenem, ertapenem, imipenem and meropenem were determined for all the CRE’s by E-test. The isolates β-lactam resistance mechanisms were further investigated by analyzing 31 different types of β–lactamase genes by polymerase chain reaction (PCR). Results: Four bacterial isolates, 3 Enterobacter cloacae and 1 Klebsiella pneumoniae, were determined to be non-susceptible to one or all of the carbapenems (ertapenem, imipenem and meropenem) tested. All isolates which carried the blaKPC-2 gene showed an extreme drug resistance profile. These isolates were resistant to all β-lactam antibiotics, co-trimoxazole and gentamicin, while susceptible to only amikacin and colistin sulfate. Different combination of plasmid encoded b–lactamase genes (blaTEM, blaSHV, blaOXA-1, blaMIR-1, blaGES-23 and blaKPC-2) were present in these isolates. Of interest, was the isolation of the first E. cloacae strains co-producing the blaKPC-2 and a novel blaGES-23 β-lactamase. Conclusions: The presence of all these plasmid encoded b-lactamase in Palestine is alarming and mandates actions to be taken to control antibiotics usage and the activation of hospital infection control programs in order to prevent the spread of these extremely drug resistant bacteria
The Antimicrobial Activity of Oil-in-Water Microemulsions is predicted by their position within the Microemulsion Stability Zone
Get PDFIt has been shown previously that thermodynamically stable oil-in-water microemulsions have significant antimicrobial activity against planktonic cells and biofilm cells over short periods of exposure. It was the aim of this study to identify whether the position of the microemulsion within the microemulsion stability zone of the pseudo-ternary phase structure predicts the efficiency of the antimicrobial action of the microemulsion. Microemulsions were formulated at different points within the microemulsion stability zone. Experiments were performed to observe the kinetics of killing of these microemulsions against selected test microorganisms (Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 10231, Staphylococcus aureus ATCC 6538 and Aspergillus niger ATCC 16404). The results indicated that the antimicrobial activity of the microemulsion is dependant upon its position within the zone of stability and is greater nearer the centre of that zone. The results indicate that significant antimicrobial activity can be observed at all points within the zone of microemulsion stability, but that maximal activity is to be found at the centre of that area
Molecular Characterization and resistance of H. influenzae isolated from Nasopharynx of Students in North Lebanon
Get PDFIntroduction: Haemophilus influenzae is an important cause of respiratory infections,including acute otitis media, sinusitis, and chronic bronchitis, which arepreceded by asymptomatic H. influenzae colonization of the human pharynx. Theaim of this study is to investigate the rate of H.influenzae nasopharyngeal colonizationamong students ages 2 to 3 years.Material and methods: A total of 21 isolates of clinical H. influenzae wereisolated from 87 nasopharyngeal specimens of children between April and June2011. The isolates were identified by using molecular techniques (PCR), biotypeswere determined by using the following tests: ornithin decarboxylase, urease andtryptophanase, and capsular typing was performed by SAST by using polyclonaland specific b antisera (Difco-BD®-USA).The prevalence of β -lactams resistance, β-lactamase production, the level of macrolideresistance was recorded for each strain by using disc diffusion and E-teststrip methods and chromogenic cephalosporin test (cefinase). β -lactams resistancegenes (blaTEM and blaROB) were determined using PCR.Results: 42.8 % of the H. influenzae isolates were type b, and biotypes I, II andIII were the majority, whereas biotypes IV, VI and VIII was not found. The majorityof capsule type b was belonged to biotype II. Antibiotics susceptibility showedthat 19% of the isolates were resistant to ampicillin and produced type TEM-1β-lactamase.Conclusion: This study shows the carriage rate of H. influenzae in North Lebanonchildren. The incidence of resistance rate of 19% to ampicillin signals an importantwarning to the future prophylaxis use of beta-lactam in treatment of H. influenzaeinfections in Lebanon
Antimicrobial resistance patterns among Acinetobacter baumannii isolated from burn intensive care unit in Tripoli, Libya
Get PDFBackground: Acinetobacter baumannii is a troublesome and increasingly problematic healthcare-associated pathogen, especially in critical care unit. These organisms have a capacity for long-term survival in the hospital environment. Aim: This study aimed to investigates the drug resistance patterns of Acinetobacter baumannii strains isolated from burn ICU (BICU). Method: The antibiotic susceptibility of 176 isolates to imipenem, meropenem, gentamicin, ciprofloxacin, fusidic acid, amikacin, trimethoprim, cefepime, ceftazidime, ceftriaxone, cefotaxime, and amoxicillin-calvulanic acid was determined by disk agar diffusion test. Findings: The overall proportion of A. baumannii isolates among all clinical isolates has increased slightly throughout the study from 3.5% to 4.2%. Carpabenem remained the antimicrobial most active antibiotic against A. braumannii isolates compared with other antibiotics, during the two years there was an increase in resistance from 50.6% to 71.3% to imipenem (P<0.01), and meropenem from 50.6% to 74.5% (P<0.01). ICU isolates exhibited significantly higher level of resistance to imipenem (71.6%) and meropenem (73.4%) compared with non-ICU strains (42.6% and 44.6% respectively) (P<0.01). Conclusion: In conclusion, the high prevalence of multidrug resistance A. baumannii (97.7%) and increased resistance to imipenem and meropenem in our unit might be due to long hospital stay, intubation, surgery and previous antibiotic prescription. It would seem that practices to prevent cross-transmission are more important in controlling resistance
Fosfomycin Trometamol in Patients with Renal Insufficiency and in the Elderly
Get PDFSingle oral dose therapy with fosfomycin trometamol (FT) 3 g is recommended inthe treatment of uncomplicated urinary tract infection (UTI) not only in premenopausal,but also in postmenopausal elderly, otherwise healthy women. It can alsobe used as reapplication every 10 days for prophylaxis of recurrent uncomplicatedcystitis. FT 3 g has also been used with two oral doses of 3 g (on two consecutivedays) for perioperative prophylaxis in transurethral interventions or with three doses(every other day, three times) for treatment of complicated lower UTI includingmany elderly patients. The tolerance and safety in the patients above 65 yearsof age did not differ from younger ones. Therefore, there is also an indication toadminister oral FT 3g in adults above 65 years of age for treatment or prophylaxisof uncomplicated UTI.Patients with renal insufficiency up to a creatinine clearance of 20 ml/min can beexpected to have still sufficiently high urinary concentrations of fosfomycin, thattreatment of cystitis should be justified from pharmacokinetic/pharmacodynamicpoint of view. From preliminary clinical results there is also an indication to useoral FT 3 g in adults with renal insufficiency up to a creatinine clearance of 20 ml/min, with single dose for treatment of lower uncomplicated UTI with otherwisenormal urinary tract or with repeated doses (every second or third day accordingto the degree of renal insufficiency) for treatment of lower complicated UTI causedby fosfomycin susceptible pathogens resistant to other oral antimicrobial drugs