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Ahmed S, Shree N, Narula AS, Nirala PK, Majid H, Garg A, Nayeem U, Khan MA. The prevalence of multidrug resistance in uropathogens of patients admitted in the intensive care unit of a tertiary care hospital. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024; 397:7117-7127. [PMID: 38643454 DOI: 10.1007/s00210-024-03108-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Accepted: 04/14/2024] [Indexed: 04/22/2024]
Abstract
Urinary tract infections (UTIs) are among the most common bacterial infections, posing significant public health challenges due to increasing antimicrobial resistance (AMR). This study aims to assess the prevalence, demographic characteristics, microbial profile, and antimicrobial resistance patterns in Indian patients with UTIs admitted to intensive care unit. A total of 154 patients with positive UTIs were included in this cross-sectional study. The prevalence data including demographics, microbial isolates, and antimicrobial susceptibility patterns were collected. Additionally, risk factors for multidrug resistance uropathogens were assessed using multivariate analyses. The patient cohort had diverse demographic, with a slight male predominance of 52.6% (n = 81). The most common comorbidities were hypertension 59.1% (n = 91) and diabetes mellitus 54.5% (n = 84). The microbial profile was dominated by gram-negative bacteria, particularly Escherichia coli 26.62% (n = 41) and Klebsiella pneumoniae 17.53% (n = 27). The predominant gram-positive and fungal isolate was Enterococcus faecium 7.14% (n = 11) and Candida spp. 18.83% (n = 29), respectively. Substantial resistance was noted against common antimicrobials, with variations across different pathogens. Gram-negative bacteria, particularly Escherichia coli and Klebsiella pneumoniae, exhibited high MDR rates, emphasizing the challenge of antimicrobial resistance. Multivariate logistic regression identified age groups 50-65 and over 65, and prolonged catheterization as significant risk factors for MDR infections. A significantly high resistance rate among pathogens emphasizes the need for judicious antimicrobial use. Our findings emphasize the necessity of ongoing surveillance and tailored interventions based on local pathogen prevalence and antibiogram data to effectively address the threat of AMR threat for better management of UTI management in ICU settings.
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Affiliation(s)
- Shaista Ahmed
- Department of Translational and Clinical Research, School of Chemical and Life Science, Jamia Hamdard, New Delhi, 110062, India
| | - Neetu Shree
- Department of Microbiology, Hamdard Institute of Medical Sciences & Research, New Delhi, 110062, India
| | - Ajit Singh Narula
- Department of Nephrology, Fortis Escort Heart Institute and Research Centre, New Delhi, 110025, India
| | - Purushottam Kr Nirala
- Department of Nephrology, Fortis Escort Heart Institute and Research Centre, New Delhi, 110025, India
| | - Haya Majid
- Department of Translational and Clinical Research, School of Chemical and Life Science, Jamia Hamdard, New Delhi, 110062, India
| | - Aakriti Garg
- Department of Translational and Clinical Research, School of Chemical and Life Science, Jamia Hamdard, New Delhi, 110062, India
- Department of Pharmacology, School of Pharmaceutical Education and Research, Jamia Hamdard, New Delhi, 110062, India
| | - Uzma Nayeem
- Department of Translational and Clinical Research, School of Chemical and Life Science, Jamia Hamdard, New Delhi, 110062, India
| | - Mohd Ashif Khan
- Department of Translational and Clinical Research, School of Chemical and Life Science, Jamia Hamdard, New Delhi, 110062, India.
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Bitew A, Zena N, Abdeta A. Bacterial and Fungal Profile, Antibiotic Susceptibility Patterns of Bacterial Pathogens and Associated Risk Factors of Urinary Tract Infection Among Symptomatic Pediatrics Patients Attending St. Paul’s Hospital Millennium Medical College: A Cross-Sectional Study [Response to Letter]. Infect Drug Resist 2022; 15:2417-2418. [PMID: 35547786 PMCID: PMC9081004 DOI: 10.2147/idr.s372299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 04/26/2022] [Indexed: 11/23/2022] Open
Affiliation(s)
- Adane Bitew
- Department of Medical Laboratory Science, College Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Nuhamen Zena
- Department of Microbiology, St Paul Hospital Millennium Medical College, Addis Ababa, Ethiopia
| | - Abera Abdeta
- National Clinical Bacteriology and Mycology Reference Laboratory, Ethiopian Public Health Institute, Addis Ababa, Ethiopia
- Correspondence: Abera Abdeta, National Clinical Bacteriology and Mycology Reference Laboratory, Ethiopian Public Health Institute, P.O. Box:1242, Addis Ababa, Ethiopia, Tel +251911566420, Email
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Iqbal Z, Mumtaz MZ, Malik A. Extensive drug-resistance in strains of Escherichia coli and Klebsiella pneumoniae isolated from paediatric urinary tract infections. J Taibah Univ Med Sci 2021; 16:565-574. [PMID: 34408614 PMCID: PMC8348552 DOI: 10.1016/j.jtumed.2021.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 03/06/2021] [Accepted: 03/10/2021] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVES Urinary tract infections (UTIs) in children are rapidly increasing worldwide and are commonly caused by extensively drug-resistant bacteria. This study determines the prevalence of UTIs in paediatric patients and evaluates the pattern of extensively drug-resistance in Escherichia coli and Klebsiella pneumoniae strains isolated from paediatric UTI patients. METHODS Uropathogenic bacterial strains were isolated from paediatric patients with UTIs admitted to the Institute of Child Health, Lahore, Pakistan. Strains of both E. coli and K. pneumoniae were identified using biochemical characterisation and subjected to antibiotic susceptibility assays for 21 common antimicrobial drugs in order to determine their extensively drug-resistant profile. RESULTS We isolated 63 E. coli and 37 K. pneumoniae strains from 130 paediatric patients with UTIs over a period of six months. The antibiotic susceptibility assays showed that both the E. coli and K. pneumoniae strains exhibited a high degree of resistance against co-amoxiclav, cefuroxime, cefixime, cefotaxime, ceftazidime, ceftriaxone, ciprofloxacin, nalidixic acid, norfloxacin, pepedemic acid, and co-trimoxazole. However, several of the antimicrobial agents, including polymyxin B, colistin sulphate, chloramphenicol, nitrofurantoin, and fosfomycin, were found to retain their antimicrobial activities against both pathogens. The five highest antibiotic resistant strains were identified as E. coli strains ZK9, ZK40, and ZK60 and K. pneumoniae ZK32 and ZK89 using 16S rRNA gene sequencing. CONCLUSION Our study demonstrates that E. coli and K. pneumonia are the dominant extensively drug-resistant uropathogenic bacteria in community-acquired UTIs in our cohort. These uropathogens were found to be resistant to the majority of the routinely-used classes of β-lactams, pyridopyrimidines, quinolones, and fluoroquinolone antibiotics, and these findings may be useful for clinicians in their treatment of paediatric UTIs.
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Affiliation(s)
- Zakia Iqbal
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Muhammad Z. Mumtaz
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
| | - Arif Malik
- Institute of Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
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Bitew A. High Prevalence of Multi-Drug Resistance and Extended Spectrum Beta Lactamase Production in Non-Fermenting Gram-Negative Bacilli in Ethiopia. Infect Dis (Lond) 2019; 12:1178633719884951. [PMID: 31723320 PMCID: PMC6836305 DOI: 10.1177/1178633719884951] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/06/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Emergence of resistance to multiple antimicrobial agents in Non-Fermenting Gram-Negative Bacilli is a major problem to public health, as it limits drug treatment options against infections. The aim of this study was to determine the prevalence of multi-drug resistance and extended spectrum beta lactamase production in Non-Fermenting Gram-Negative Bacilli. MATERIALS AND METHODS Different clinical samples were collected and processed following standard procedures. Each sample was then inoculated onto culture media. Identification, drug susceptibility testing, and extended spectrum beta lactamase production of the isolates were carried out by using the VITEK 2 compact system. RESULTS Among 996 clinical samples, 135 samples yielded Non-Fermenting Gram-Negative Bacilli of which Pseudomonas and Acinetobacter species were the commonest isolates. The overall drug resistance rates of Non-Fermenting Gram-Negative Bacilli were above 80% against ampicillin (89.6%), cefuroxime axetil (88.9%), nitrofurantoin (85.9%), cefalotin (84.4%), cefoxitin (83.7%), cefazolin (83.0%), and cefuroxime (83.0%). Tobramycin with a resistance rate of 19.3% was the most active antimicrobial agent. Out of 135 isolates, 81.5% were multi-drug resistant of which 13.3% were extensively drug resistant and 10.4% were pandrug resistant. Extended spectrum beta lactamase production was detected in 48.9% of the isolates. CONCLUSIONS The spectrum of bacterial species isolated was diverse. The isolates demonstrated high level of drug resistance in different classes of antibiotics. The magnitude of multi-drug resistance and the level of extended spectrum beta lactamase production were high. Hence, further studies on multi-drug resistant and extended spectrum beta lactamase producing Non-Fermenting Gram-Negative Bacilli both in the community and in hospital setting are essential.
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Affiliation(s)
- Adane Bitew
- Department of Medical Laboratory Sciences, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
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Pouladfar G, Basiratnia M, Anvarinejad M, Abbasi P, Amirmoezi F, Zare S. The antibiotic susceptibility patterns of uropathogens among children with urinary tract infection in Shiraz. Medicine (Baltimore) 2017; 96:e7834. [PMID: 28906365 PMCID: PMC5604634 DOI: 10.1097/md.0000000000007834] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Urinary tract infection (UTI) is one of the most common bacterial infections in pediatrics. Delay in diagnosis and treatment can cause significant morbidity. The physicians knowledge regarding the symptoms, microorganisms that caused UTI, and effective antibiotics in a geographical area can help them to select the appropriate antibiotics. This study was performed to determine the prevalence of bacteria that cause UTI and their susceptibility to common antibiotics as well as the common symptoms and associated factors in children of Shiraz, Southern Iran.This cross sectional study was performed among 202 children with UTI, aged 2 months to 18 years old, between August and November 2014 in pediatric medical centers of Shiraz University of Medical Sciences. Urine samples were collected using urinary catheter or suprapubic in children < 2 years and mid-stream in children over 2 years, respectively. The type of micro-organisms causing UTI was determined and evaluation of antibiotic susceptibility for each organism was assayed by the Kirby Bauer method using antibiogram test. Patient's information was collected through checking the medical documents and interview with parents.Our results showed that the frequency of UTI was significantly higher in girls (70.3%) than in boys. The most commonly discovered pathogens were Escherichia coli (E coli) (51.5%), followed by Klebsiella spp. (16.8%), and Enterococcus spp. (9.9%). Overall susceptibility test showed the highest resistance to ampicillin (81.2%) and cotrimoxazole (79.2%), and the highest sensitivity to imipenem (90.1%) and Gentamicin (65.3%). Gram negative and positive bacteria showed the highest antibiotic resistance to amoxicillin (83.8%) and clindamycin (100%), respectively. In addition, production of extended spectrum beta lactamase (ESBL) was 69.2% and 30.8% in E coli and Kelebsiella respectively.The efficacy of third generation of the cephalosporins was reduced because of the high rate of production of ESBL and drug resistance. These results inform the physician as to which antibiotics are appropriate to prescribe for the patient, as well as urine culture reports and following the patient's clinical response so that high antimicrobial resistance is not developed at the community level.
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Affiliation(s)
| | | | | | - Pejman Abbasi
- Alborzi Clinical Microbiology Research Center, Nemazee Teaching Hospital
| | | | - Samaneh Zare
- Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran
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Mishra MP, Sarangi R, Padhy RN. Prevalence of multidrug resistant uropathogenic bacteria in pediatric patients of a tertiary care hospital in eastern India. J Infect Public Health 2016; 9:308-14. [DOI: 10.1016/j.jiph.2015.10.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 09/12/2015] [Accepted: 10/07/2015] [Indexed: 11/29/2022] Open
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Alavi SM, Sharifi M, Eghtesad M. Bacterial sepsis: challenges of diagnosis and treatment in a teaching hospital southwest of iran. Jundishapur J Microbiol 2014; 7:e9082. [PMID: 25147683 PMCID: PMC4138650 DOI: 10.5812/jjm.9082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 02/21/2013] [Accepted: 06/17/2013] [Indexed: 11/16/2022] Open
Abstract
Background: Management of bacterial sepsis as a common cause of hospitalization and a life threatening clinical syndrome is a challenge. In previous studies, incorrect diagnosis of sepsis and unnecessary treatment have been frequently reported. Objectives: The aim of this study was to evaluate the diagnosis and treatment of cases with a primary diagnosis of sepsis. Patients and Methods: Of 410 medical files of patients with primary diagnosis of bacterial sepsis, 187 fulfilled our criteria and were enrolled in the study. The study was conducted in Razi Hospital of Ahvaz, southwest Iran, from 2009 to 2011. Data included demographic characteristics, underlying disease, clinical symptoms, laboratory and imaging findings, administrated antibacterial drugs, and nurses and doctors-analyzed notes. For evaluation of the diagnosis, patients were divided to two groups, sepsis group and pseudosepsis group, and for evaluation of the treatment, patients were categorized in appropriate and inappropriate treatment groups and compared using SSPS software version 16 by chi-square and fisher exact tests. P-values less than 0.05 were considered significant. Results: Out of 187 cases, 61 were in the intensive care unit (ICU), 98 in the infectious disease ward, and 28 in the internal medicine ward. Correct diagnosis of sepsis in the ICU, internal and infectious diseases wards were made in 16 (26.2%), 4 (14.3%) and 71 (72.4%) cases, respectively. Appropriate treatments for sepsis in the ICU, internal and infectious wards were applied in 12 (19.7%), 3 (10.7%) and 61 (78.2%) cases, respectively. Ninety-one patients (48.6%) were diagnosed correctly (true sepsis) and 76 (40.6%) were treated with proper regimes. Conclusions: Inappropriate and unnecessary use of antibiotics by patients with preliminary diagnosis of sepsis in our hospital, similar to other parts of the world, was high.
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Affiliation(s)
- Seyed Mohammad Alavi
- Infectious and Tropical Diseases Research Center, Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Mehrdad Sharifi
- Ahvaz Health Center, Jundishapur University of Medical Sciences, Ahvaz, IR Iran
- Corresponding author: Mehrdad Sharifi, Ahvaz Health Center, Jundishapur University of Medical Sciences, Ahvaz, IR Iran. Tel: +98-6113387724 , E-mail:
| | - Mehdi Eghtesad
- Khuzestan Health Center, Jundishapur University of Medical Sciences, Ahvaz, IR Iran
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Mahmoudi L, Mohammadpour AH, Niknam R, Ahmadi A, Mojtahedzdeh M. Limited sampling strategy for estimation of amikacin optimal sampling time in critically ill adults. Anaesth Intensive Care 2014; 42:228-233. [PMID: 24580389 DOI: 10.1177/0310057x1404200210] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Aminoglycosides are a class of antibiotics that are commonly used in the treatment of gram-negative pathogens in the critically ill population. Unfortunately, dosing of these aminoglycosides in critically ill patients is difficult due to their altered pharmacokinetics in the critically ill and narrow therapeutic index. In this study, we evaluated whether a limited sampling strategy can be used to predict the area under the concentration (AUC) curve of amikacin concentrations over a 24-hour period after a single dose of intravenous amikacin (25 mg/kg). This open-labelled, non-comparative prospective study recruited 20 adult critically ill trauma patients with a diagnosis of hospital-acquired infection. We assessed the best estimate of plasma amikacin concentrations over a 24-hour period by multiple stepwise regression, using nine blood samples during this study period as the gold standard. Using a jackknife procedure, the AUC of amikacin over a 24-hour period was estimated by choosing a combination of the amikacin concentrations measured at different time-points. Overall, the mean prediction error of all models was not statistically different from zero (P >0.05). Based on bias and imprecision, all models gave good estimate of AUC of amikacin over a 24-hour period, but a two-point sampling strategy at 1.5 and 6 hours post-dose appeared to offer the best compromise between accuracy and cost-effectiveness in optimising the dosing of amikacin in critically ill patients.
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Affiliation(s)
- L Mahmoudi
- General Intensive Care Unit, Sina Teachning Hospital affiliated to the School of Medicine, Tehran University of Medical Sciences
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Bugs, hosts and ICU environment: countering pan-resistance in nosocomial microbiota and treating bacterial infections in the critical care setting. ACTA ACUST UNITED AC 2014; 61:e1-e19. [PMID: 24492197 DOI: 10.1016/j.redar.2013.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 11/04/2013] [Indexed: 02/07/2023]
Abstract
ICUs are areas where resistance problems are the largest, and these constitute a major problem for the intensivist's clinical practice. Main resistance phenotypes among nosocomial microbiota are (i) vancomycin-resistance/heteroresistance and tolerance in grampositives (MRSA, enterococci) and (ii) efflux pumps/enzymatic resistance mechanisms (ESBLs, AmpC, metallo-betalactamases) in gramnegatives. These phenotypes are found at different rates in pathogens causing respiratory (nosocomial pneumonia/ventilator-associated pneumonia), bloodstream (primary bacteremia/catheter-associated bacteremia), urinary, intraabdominal and surgical wound infections and endocarditis in the ICU. New antibiotics are available to overcome non-susceptibility in grampositives; however, accumulation of resistance traits in gramnegatives has led to multidrug resistance, a worrisome problem nowadays. This article reviews microorganism/infection risk factors for multidrug resistance, suggesting adequate empirical treatments. Drugs, patient and environmental factors all play a role in the decision to prescribe/recommend antibiotic regimens in the specific ICU patient, implying that intensivists should be familiar with available drugs, environmental epidemiology and patient factors.
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[Urinary tract colonization and infection in critically ill patients]. Med Intensiva 2011; 36:143-51. [PMID: 21839547 DOI: 10.1016/j.medin.2011.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 06/23/2011] [Accepted: 06/30/2011] [Indexed: 11/23/2022]
Abstract
Urinary tract infections (UTIs) account for 20-50% of all hospital-acquired infections occurring in the intensive care unit (ICU). In some reports UTI was found to be more frequent than hospital-acquired pneumonia and intravascular device bacteremia, with a greater incidence in developing countries. The risk factors associated with the appearance of UTI include the severity of illness at the time of admission to the ICU, female status, prolonged urinary catheterization or a longer ICU stay and poor urinary catheter management - mainly disconnection of the closed system. about the present study offers data on the epidemiology of UTI in the ICU, the identified risk factors, etiology, diagnosis, impact upon morbidity and mortality, and the measures to prevent its appearance.
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Tay MKX, Lee JYC, Wee IYJ, Oh HML. Evaluation of Intensive Care Unit-acquired Urinary Tract Infections in Singapore. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2010. [DOI: 10.47102/annals-acadmedsg.v39n6p460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Introduction: Urinary tract infections remain one of the most frequently encountered acquired complications in an intensive care unit (ICU). The objective of this study was to determine the incidence, risk factors, microbial sensitivity patterns, and clinical outcomes of patients with UTIs acquired during their admission to an ICU in an acute care hospital in Singapore. Materials and Methods: This was a 14-week prospective study. All ICU patients ≥18 years who remained in the ICU for ≥48 hours were eligible for this study. Patients were reviewed daily and the presence of an ICU-acquired UTI was identified via urinary microscopic examination or culture results. Other data collected included patient demographics, ICU admission criteria, concomitant illnesses, presence of invasive lines, microbial sensitivity and treatment outcomes. Results: Thirty-five (13.7%) cases of ICU-acquired UTI occurred in 256 separate ICU admissions. The most common micro-organisms isolated were Candida spp. (34%). Female gender and prior exposure to antibiotics were independent risk factors for developing an ICU-acquired UTI (P <0.01). Both mean length of ICU stay and duration of catheterisation were significantly longer for patients with ICU-acquired UTI (P <0.001). The mortality rate of patients with ICU-acquired UTIs (12.1%) was slightly higher than those without (9.9%). Conclusions: The incidence of ICU-acquired UTIs was similar to figures reported for nosocomial UTIs from the previous studies. Significant risk factors for developing an ICU-acquired UTI were female gender and history of antibiotic exposure prior to ICU admission. The insignificant link between ICU-acquired UTI and mortality requires further investigation in larger cohorts.
Key words: Medical and surgical ICUs, Nosocomial UTI, Outcomes, Risk factors
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Niu L, Fang M, Jiao K, Tang L, Xiao Y, Shen L, Chen J. Tetrapod-like Zinc Oxide Whisker Enhancement of Resin Composite. J Dent Res 2010; 89:746-50. [PMID: 20439932 DOI: 10.1177/0022034510366682] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
There is an increasing demand for composite resins with both strong antibacterial activity and satisfactory mechanical properties. This study tested the hypothesis that the new antibacterial agent tetrapod-like zinc oxide whisker (T-ZnOw) could simultaneously enhance the antibacterial activity and mechanical properties of a two-component composite resin. The antibacterial activities of the materials were assessed by the broth dilution test and direct contact test. Optical microscopy, scanning electron microscopy, and measurements of the flexural strength, compressive strength, and diametral tensile strength were carried out for mechanical characterization. The results revealed that T-ZnOw provided the resin with strong antibacterial activity and improved mechanical properties in all tested groups. However, the antibacterial activity of the resin with 10% T-ZnOw in the powder component significantly decreased after aging treatment. The incorporation of 5% T-ZnOw into the resin powder was optimal to give appropriate antibacterial activity, long-term antibacterial effectiveness, and mechanical properties.
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Affiliation(s)
| | - M. Fang
- Department of Prosthodontics
| | - K. Jiao
- Department of Oral Anatomy and Physiology and TMD
| | - L.H. Tang
- Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, 145 West Changle Road, Xi’an, 710032, P.R. China
| | - Y.H. Xiao
- Department of Stomatology, Kunming General Hospital of PLA, Kunming, China
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