Detection Rate Of Methicillin-resistant Staphylococcus Aureus Research Articles

Implications of deduplication on the detection rates of multidrug-resistant organism (MDRO) in various specimens: insights from the hospital infection surveillance program

BackgroundCurrently, different guidelines recommend using different methods to determine whether deduplication is necessary when determining the detection rates of multidrug-resistant organisms (MDROs). However, few studies have investigated the effect of deduplication on MDRO monitoring data. In this study, we aimed to investigate the influence of deduplication on the detection rates of MDROs in different specimens to assess its impact on infection surveillance outcomes.MethodsSamples were collected from hospitalized patients admitted between January 2022 and December 2022; four types of specimens were collected from key monitored MDROs, including sputum samples, urine samples, blood samples, and bronchoalveolar lavage fluid (BALF) samples. In this study, we compared and analysed the detection rates of carbapenem-resistant Klebsiella pneumoniae (CRKP), carbapenem-resistant Escherichia coli (CRECO), carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Pseudomonas aeruginosa (CRPA), and methicillin-resistant Staphylococcus aureus (MRSA) under two conditions: with and without deduplication.ResultsWhen all specimens were included, the detection rates of CRKP, CRAB, CRPA, and MRSA without deduplication (33.52%, 77.24%, 44.56%, and 56.58%, respectively) were significantly greater than those with deduplication (24.78%, 66.25%, 36.24%, and 50.83%, respectively) (all P < 0.05). The detection rates in sputum samples were significantly different between samples without duplication (28.39%, 76.19%, 46.95%, and 70.43%) and those with deduplication (19.99%, 63.00%, 38.05%, and 64.50%) (all P < 0.05). When deduplication was not performed, the rate of detection of CRKP in urine samples reached 30.05%, surpassing the rate observed with deduplication (21.56%) (P < 0.05). In BALF specimens, the detection rates of CRKP and CRPA without deduplication (39.78% and 53.23%, respectively) were greater than those with deduplication (31.62% and 42.20%, respectively) (P < 0.05). In blood samples, deduplication did not have a significant impact on the detection rates of MDROs.ConclusionDeduplication had a significant effect on the detection rates of MDROs in sputum, urine, and BALF samples. Based on these data, we call for the Infection Prevention and Control Organization to align its analysis rules with those of the Bacterial Resistance Surveillance Organization when monitoring MDRO detection rates.

The Prevalence, Epidemiological, and Molecular Characterization of Methicillin-Resistant Staphylococcus aureus (MRSA) in Macau (2017-2022).

Macau, recognized as a global tourism hub and the world's most densely populated region, provides a unique environment conducive to methicillin-resistant Staphylococcus aureus (MRSA) transmission in healthcare and community settings, posing a significant public health concern both locally and globally. The epidemiology and molecular characteristics of MRSA in the distinct city of Macau remain largely unelucidated. This five-year longitudinal study (2017-2022) examined the local prevalence and molecular typing of MRSA in Macau, with future MRSA type distribution predicted through ARIMA modeling. We subsequently analyzed the epidemiological characteristics of MRSA, including specimen source, clinical department, collection year, season, patient age, sex, and the annual number of tourists. Comprehensive antibiotic resistance profiles of the strains were also assessed. Of 504 clinically isolated S. aureus strains, 183 (36.3%) were identified as MRSA by the cefoxitin disk diffusion method and validated through multi-locus sequence typing (MLST). The MRSA detection rate showed an upward trend, increasing from 30.1% in 2017 to 45.7% in 2022. SCCmec type IV was predominant (28.9%), followed by types II (25.4%), III (22.1%), and V (22.1%). The primary sources of MRSA isolates were sputum (39.2%) and secretions (25.6%). Older age emerged as a risk factor for MRSA infection, whereas no significant associations were found with seasonal variations, gender, or the annual number of tourists. Despite displaying universal resistance to cefoxitin, oxacillin, and benzylpenicillin, MRSA isolates in Macau remained fully sensitive to vancomycin, tigecycline, quinupristin, nitrofurantoin, and linezolid. Continuous surveillance and analysis of MRSA distribution in Macau could provide invaluable insights for the effective management of MRSA prevention and control measures within healthcare settings.

Bacteriology and trends of antimicrobial resistance of Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus in otitis media: A retrospective data analysis.

Otitis media (OM) has a high prevalence worldwide and the treatment is crucial because hearing loss in children can lead to growth disorders such as language development disorders. The aim of this study is to analyse the changes in bacterial strains and the trends of antibiotic susceptibility in otitis media with effusion (OME), chronic otitis media (COM) and cholesteatomatous otitis media (Chole OM). This retrospective study involved 2926 patients diagnosed with OME, COM, or Chole OM between January 2000 and December 2020. The clinical data were collected and analysed through chart review from May 2021 to July 2021. Two tertiary medical centres. The 2926 OM patients. An otorrhea sample was collected on the first day of their hospital visit. Middle ear fluid samples for bacterial culture and antibiotics susceptibility test were collected from patients during middle ear surgery, including ventilation tube insertion. In each type of OM, the distribution of bacterial strains in the 2000s and the 2010s was compared. In addition, changes in the detection rate of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PA) and trends in their antibiotic susceptibility over the last 10 years were analysed. The most frequently detected bacterial strains in OME, COM and Chole OM over the study period were coagulase-negative Staphylococcus (CNS) (29.6%), MRSA (24.1%), and PA (20.1%). Compared to the 2000s, the proportion of non-typable Haemophilus influenzae in OME and MRSA in COM increased in the 2010s (27.4%-31.6% and 1.5%-29.5%, respectively). In total three types of OM, although there was no significant trend of change in detection rates of MRSA, PA, and multidrug resistant-P. aeruginosa (MDR-PA) during the last 10 years, resistance to the Quinolone class of MRSA and PA tended to increase (P < .05). The composition of bacterial strains in each types of OM has changed over the past 20 years. Additionally, the antibiotic resistance of MRSA and PA has increased in the last decade. Therefore, when using empirical antibiotics in necessary situations, it is necessary to change to an appropriate antibiotic through a bacterial culture test and antimicrobial susceptibility test.

Comparison of cefoxitin disc diffusion test, HiCrome rapid MRSA agar and PCR for&lt;em&gt; mec&lt;/em&gt;A, PVL and &lt;em&gt;fem&lt;/em&gt;B genes for detection of methicillinresistant &lt;em&gt;Staphylococcus aureus&lt;/em&gt; (MRSA)

This study evaluates the effectiveness of cefoxitin disk diffusion as a method to detect methicillin-resistant Staphylococcus aureus (MRSA), comparing with HiCrome MRSA screening agar and PCR-based mecA gene detection. Both PCR and the cefoxitin disk diffusion test exhibited 100% sensitivity and specificity, while HiCrome agar showed slightly lower sensitivity (90%) and specificity (95.24%) out of 72 Staphylococcus aureus isolates. The MRSA detection rate was found to be 41.66%, with femB and PVL genes present in 86.6% and 13.3% of MRSA isolates, respectively. Cefoxitin could serve as a reliable substitute marker for MRSA detection, particularly in settings with limited resources.

Correlation Analysis of Staphylococcus aureus Drug Resistance and Virulence Factors with Blood Cell Counts and Coagulation Indexes.

The influence of different Staphylococcus aureus variants on blood cells and coagulation system was evaluated by investigating the carrying status of drug resistance genes and virulence genes of methicillin-resistantStaphylococcus aureus (MRSA) and methicillin-sensitiveStaphylococcus aureus (MSSA). A total of 105 blood culture-derivedStaphylococcus aureus strains were collected. The carrying status of drug resistance genes mecA and three virulence genes tst, pvl, and sasX was analyzed by polymerase chain reaction (PCR). The changes in routine blood routine counts and coagulation indexes of patients infected with different strains were analyzed. The results showed that the positive rate of mecA was consistent with that of MRSA. Virulence genes tst and sasX were detected only in MRSA. Compared with MSSA, patients infected with MRSA or MSSA patients infected with virulence factor, leukocyte count and neutrophil count in peripheral blood were significantly increased, and the platelet count decreased to a higher degree. Part thromboplastin time increased, D-dimer increased, but fibrinogen content decreased more. The changes of erythrocyte and hemoglobin had no significant correlation with whether Staphylococcus aureus carried virulence genes. The detection rate of MRSA in patients with positive Staphylococcus aureus in blood culture had exceeded 20%. The detected MRSA bacteria carried three virulence genes, tst, pvl, and sasX, which were more likely than MSSA. MRSA, which carries two virulence genes, is more likely to cause clotting disorders.

CHARACTERIZATION OF MULTI-DRUG RESISTANCE LIVESTOCK ACQUIRED METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS (LA-MRSA) ISOLATES FROM DIFFERENT SWINE FARMS IN ENUGU METROPOLIS, NIGERIA

Aim and Objective: Globally, livestock animals, particularly swine, calves and poultry are colonized by Livestock acquired methicillin resistant Staphylococcus aureus (S. aureus) (LA-MRSA). This study was aimed at screening for multi-drug resistant in LA-MRSA strains isolated from swine from selected swine farm within Enugu metropolis. Methods: A total of 307 pig nasal swabs samples were collected, from farm A (76), farm B (116) and from C (108) in Enugu metropolis. Then within 1 hour of collection, samples were transferred to the Caritas University Microbiology Laboratory unit for bacteriological analysis using a standard microbiological isolation and identification protocol. Isolated S. aureus and LA-MRSA strain were phenol-typing screened and identified for MRSA using Kirby-Bauer disc diffusion method with 1 μg oxacillin/30μg cefoxitin antibiotic Disc and Tetracycline Disk Test respectively. Antibiogram studies of LA-MRSA against several antibiotic discs and multiple antibiotic resistance indexes were determined. Results: Results showed overall isolation rate of 76.2 % S. aureus comprising of 90.5 %, 80.3 % and 62.9 % in Farm B, Farm A and Farm C respectively, total MRSA detection rate of 125 (40.7%) comprising Farm A 50.0 %, Farm B 46.6 %, Farm C 30.6 %. LA-MRSA were identified in 84(27.4%) of swine with high proportion of 29(38.2 %) in Farm A followed by Farm C30(27.8%) and Farm B 25(21.6 %). LA-MRSA from Farm A Nursery: 27.3%, Weaning 0.0 %, Grower 77.0 % while Farm B Nursery 24.1 %, Weaning 0.0 %, Grower 7.3 %, finisher 100 % and Farm C Nursery 28.0 %, Grower 34.5 % and finisher 53.3 %. LA-MRSA isolates exhibited a significantly (p≤0.05) high % resistance within the range of 50-100 % against tetracycline, erythromycin, cefotaxime, clindamycin, Trimethoprim-Sulfamethoxazole and exhibit MDR with MARI value ≥0.3 but were susceptible to ciprofloxacin 77.8 %, amikacin 100 % and imipenem 100 %. Conclusion: LA-MRSA strains increased levels of MDR phenotype suggest that the emergence of LA-MRSA in swine up keeping could be promoted through veterinary antibiotics. Thus, to prevent antimicrobial resistance in both animals and humans, joint cross-examination of multi-resistant livestock acquired S. aureus, with an incorporated ‘One Health’ advancement are needed for effective curbing and control measures for LA-MRSA infections. Peer Review History: Received: 1 September 2022; Revised: 12 October; Accepted: 4 November, Available online: 15 November 2022 Academic Editor: Prof. Dr. Gorkem Dulger, Duzce University, Turkey, gorkemdulger@yandex.com Received file: Reviewer's Comments: Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. U. S. Mahadeva Rao, Universiti Sultan Zainal Abidin, Terengganu Malaysia, raousm@gmail.com Prof. Cyprian Ogbonna ONYEJI, Obafemi Awolowo University, Ile-Ife, Nigeria, conyeji@oauife.edu.ng Similar Articles: PREVALENCE OF METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS (MRSA) AND ANTIMICROBIAL SUSCEPTIBILITY PATTERNS AT A PRIVATE HOSPITAL IN SANA'A, YEMEN

A longitudinal survey of methicillin-resistant Staphylococcus aureus carriage in nursing homes and the long-term care facility in Taiwan

We conducted a longitudinal survey for methicillin-resistant Staphylococcus aureus (MRSA) carriage in nursing homes and long-term care facilities (LTCFs) in northern Taiwan. From July 2016 to February 2017, healthcare workers and residents in four institutions were enrolled. One swab sample from nares and another swab sample from umbilicus were obtained from each participant for detection of MRSA at enrolment and then follow-up samples were collected every two months for additional three times if feasible. We enrolled a total of 194 participants, including 127 residents and 67 healthcare workers. MRSA colonization rates were 23.2%, 22.8%, 20.7% and 18.6% at enrolment, the 2-, 4-, and 6-month follow-up survey, respectively, and the cumulative colonization rate was 40.2%. The MRSA detection rate was significantly higher at Institution 2 (70.7%) than that at other three institutions (25.7%∼35%) (p<0.001). Among 78MRSA carriers, 45 were found to be colonized at enrolment, and other 33 were newly identified as MRSA colonization during follow-up. Of 172MRSA isolates identified, there were two major clones, sequence types (ST) 45 (49.4%), and ST30 (25%). ST45 prevailed in three institutions and ST30 prevailed in two institutions. Nearly one in five residents or healthcare workers in nursing homes and LTCFs harbored MRSA, mostly ST45 or ST30 strains, at any given time point in the study. The prevalence and molecular epidemiology of MRSA could vary in different institutions and molecular evidence for intra- and inter-institutional spread of MRSA was provided.

Antimicrobial Resistance Among Pathogens Causing Bloodstream Infections: A Multicenter Surveillance Report Over 20 Years (1998-2017).

PurposeBloodstream infections (BSIs) are a common consequence of infectious diseases and cause high morbidity and mortality. Appropriate antibiotic use is critical for patients’ treatment and prognosis. Long-term monitoring and analysis of antimicrobial resistance are important in guiding physicians to choose appropriate antibiotics and understand the changes in antimicrobial resistance and infection control. Here, we report a retrospective study on the trends of antimicrobial resistance in the common BSI-associated pathogens.MethodsThe identification of strains and antimicrobial susceptibility tests were performed in each anticipating hospital independently. Data from the Hubei Province Antimicrobial Resistance Surveillance System (HBARSS) from 1998 to 2017 were retrospectively analyzed using WHONET 5.6 software.ResultsData from HBARSS (1998–2017) revealed that 40,518 Gram-positive bacteria and 26,568 Gram-negative bacteria caused BSIs, the most common of which were Staphylococcus aureus and Escherichia coli. Salmonella typhi was a predominant BSI-associated pathogen in 1998–2003. Antimicrobial susceptibility data showed that the resistance rates of E. coli and Klebsiella pneumoniae to cefotaxime were significantly higher than those to ceftazidime. The proportion of strains of special antimicrobial resistance phenotypes including difficult-to-treat resistance (DTR), carbapenem-resistant (CR), extended-spectrum cephalosporin resistant (ECR) and fluoroquinolone resistant (FQR) in E. coli was 0.18%, 0.26%, 13.95%, 22.78% while in K. pneumoniae was 11.95%, 14.00%, 31.91% and 11.40%, respectively. In 2013–2017, K. pneumoniae showed resistance levels reaching 15.8% and 17.5% to imipenem and meropenem, respectively, and Acinetobacter baumannii showed high resistance rates ranging from 60 to 80% to common antibiotics. The detection rate of Salmonella typhi resistance to third-generation cephalosporins and fluoroquinolones was less than 5%. Control of methicillin-resistant Staphylococcus aureus (MRSA) remains a major challenge, and in 2009–2017, the MRSA detection rate was 40–50%.ConclusionPrevalence of CR K. pneumoniae has increased significantly in recent years. Resistance rates of A. baumannii to common antimicrobial agents have increased exponentially, reaching high levels. MRSA remains a challenge to control. For K. pneumoniae, DTR, CR, ECR and FQR were antimicrobial resistance phenotypes that could not be ignored while for E. coli DTR and CR were rare antimicrobial resistance phenotypes. CR K. pneumoniae, A. baumannii and MRSA present major challenges for controlling BSIs.

High Concentration and Frequent Application of Disinfection Increase the Detection of Methicillin-Resistant Staphylococcus aureus Infections in Psychiatric Hospitals During the COVID-19 Pandemic.

The tolerance of certain multi-drug resistant bacteria to disinfectants may be promoted while the requirements of environmental disinfection have been raised in the high-risk areas of medical institutions during the COVID-19 pandemic. The current research addressed the mechanisms underlying a sharp increase in the detection of methicillin-resistant Staphylococcus aureus (MRSA) observed in a closed-management unit of elderly patients with mental disorders in 2020 as compared with the previous 4 years. We first conducted microbial detection in staff-hand and environment and a molecular epidemiology analysis, rejecting the hypothesis that the MRSA increase was due to an outbreak. Afterward, we turned to disinfectant concentration and frequency of use and analyzed the varied MRSA detection rates with different concentrations and frequencies of disinfection in 2020 and the previous 4 years. The MRSA detection rate increased with elevated concentration and frequency of disinfection, with 1,000 or 500 mg/L two times per day since January in 2020 vs. 500 mg/L 2–3 times per week in 2016–2019. When the disinfectant concentration was reduced from 1,000 to 500 mg/L, the MRSA detection decreased which indicated a modulatory role of disinfectant concentration. With a sustained frequency of disinfection in 2020, the MRSA detection rate was still higher, even after May, than that in the previous years. This suggested that the frequency of disinfection also contributed to the MRSA increase. Overall, the MRSA detection was augmented with the increase in disinfection concentration and frequency during the COVID-19 epidemic, suggesting that highly-concentrated and highly-frequent preventive long-term disinfection is not recommended without risk assessments in psychiatric hospitals.

Molecular and Anti-Microbial Resistance (AMR) Profiling of Methicillin-Resistant Staphylococcus aureus (MRSA) from Hospital and Long-Term Care Facilities (LTCF) Environment.

To provide evidence of the cross-contamination of emerging pathogenic microbes in a local network between long-term care facilities (LTCFs) and hospitals, this study emphasizes the molecular typing, the prevalence of virulence genes, and the antibiotic resistance pattern of methicillin-resistant Staphylococcus aureus. MRSA isolates were characterized from 246 samples collected from LTCFs, medical tubes of LTCF residents, and hospital environments of two cities, Chiayi and Changhua. Species identification, molecular characterization, and drug resistance analysis were performed. Hospital environments had a higher MRSA detection rate than that of LTCF environments, where moist samples are a hotspot of MRSA habitats, including tube samples from LTCF residents. All MRSA isolates in this study carried the exfoliative toxin eta gene (100%). The majority of MRSA isolates were resistant to erythromycin (76.7%), gentamicin (60%), and ciprofloxacin (55%). The percentage of multidrug-resistant MRSA isolates was approximately 50%. The enterobacterial repetitive intergenic consensus polymerase chain reaction results showed that 18 MRSA isolates belonged to a specific cluster. This implied that genetically similar isolates were spread between hospitals and LTCFs in Changhua city. This study highlights the threat to the health of LTCFs’ residents posed by hospital contact with MRSA.

Increased multidrug resistant isolates: new clinical burdens for 66 hospitals in Shanghai, 2015 to 2017.

To investigate the etiology of urinary tract and respiratory infections and the rate of drug resistant bacteria in Shanghai from 2015 to 2017, provide the support to the promotion of the correct clinical etiological specimens detection. The retrospective questionnaire survey was conducted to obtain the antibiotic prescription rate, pathogen detection rate, and isolation rate of drug-resistant bacteria of the inpatients in 66 hospitals of Shanghai in 2015 and 2017. Although the detection rate of multidrug-resistant bacteria in sputum specimens has decreased, the clinical pathogen detection still relied mainly on sputum specimens in 2017. Among the sputum specis, the detection rates of extended-spectrum β-lactamase-producing Escherichia (ESBL-ESC), extended-spectrum β-lactamase Klebsiella pneumoniae (ESBL-KP), carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Pseudomonas aeruginosa (CRPA) and methicillin-resistant Staphylococcus aureus (MRSA) in 2017 were 66.67%, 32.46%, 61.74%, 32.01% and 58.55% respectively. The detection rates of ESBL-ESC, ESBL-KP, CRAB, CRPA in 2017 were increased while the MRSA was decreased than 2015 (P<0.001). Among the blood samples, the detection rates of ESBL-ESC, ESBL-KP, CRAB, CRPA, MRSA and vancomycin-resistant Enterococcus sp (VRE) in 2017 were 53.71%, 31.43%, 50.80%, 19.43%, 43.87% and 0.55% respectively. The detection rates of ESBL-KP, CRAB, CRPA and MRSA increased while the rates of ESBL-ESC and VRE decreased compared with 2015 (P<0.005). The pathogens of multi-drug resistant bacteria were mainly detected from sputum specimens in 2017, which were all higher than detected from the blood specimens (P<0.001). Most of the multi-drug resistant bacteria in Shanghai, especially in Acinetobacter baumannii or Pseudomonas aeruginosa are mainly detected from sputum specimens, indicating that the actual drug resistance may be overestimated.

Analysis of distribution and drug resistance of pathogens isolated from 159 patients with catheter-related bloodstream infection in burn intensive care unit

Objective: To analyze the distribution and drug resistance of pathogens isolated from patients with catheter-related bloodstream infection (CRBSI) in burn intensive care unit (BICU). Methods: From January 2011 to December 2018, among 2 264 patients who were peripherally inserted central venous catheter at the BICU of the First Affiliated Hospital of Army Medical University (the third Military Medical University), hereinafter referred to as the author's unit, 159 patients were diagnosed CRBSI, including 131 males and 28 females, aged 43 (1, 79) years. The pathogens primarily isolated from peripheral venous blood and central venous catheter blood/anterior central venous catheter specimen of patients with CRBSI were retrospectively analyzed. API bacteria identification kits and automatic microorganism identification instrument were used to identify pathogens. Broth micro-dilution method or Kirby-Bauer paper disk diffusion method was used to detect the drug resistance of the pathogens to 5 antifungal drugs including fluconazole and itraconazole, etc., and 37 antibacterial drugs including tigecycline and imipenem, etc. Modified Hodge test was used to further identify imipenem- and meropenem-resistant Klebsiella pneumonia. D test was used to detect erythromycin-induced clindamycin resistant Staphylococcus aureus. The WHONET 5.6 software was applied to analyze the annual incidence of CRBSI, mortality of patients with CRBSI, incidence of CRBSI cases, distribution of infection site, and duration of catheterization, detection of Gram-negative and Gram-positive bacteria, fungi, methicillin-resistant Staphylococcus aureus (MRSA), and methicillin-sensitive Staphylococcus aureus (MSSA), and drug resistance of fungi and major Gram-negative and Gram-positive bacteria to the commonly used antibiotics in clinic. Results: (1) The incidence of CRBSI was 7.0% (159/2 264) during the eight years, which was slightly higher in 2014 and 2017 with 13.6% (30/221) and 11.1% (24/217) respectively. The mortality rate of patients with CRBSI was 7.5% (12/159). (2) The incidence of CRBSI cases was 14.9% (338/2 264); the main infection site was femoral vein, totally 271 cases (80.2%), and the duration of catheterization of this site was 9 (2, 25) d. (3) During the eight years, totally 543 strains of pathogens were isolated, including 353 (65.0%) strains of Gram-negative bacteria, 140 (25.8%) strains of Gram-positive bacteria, and 50 (9.2%) strains of fungi. The top three isolated pathogens with isolation rate from high to low were Acinetobacter baumannii, Staphylococcus aureus, and Pseudomonas aeruginosa, accounting for 23.2% (126/543), 17.1% (93/543), and 15.7% (85/543), respectively. Fungi were mainly Candida parapsilosis. Among the Staphylococcus aureus, the detection rate of MRSA was 98.9% (92/93), and that of MSSA was 1.1% (1/93). (4) Except for the low drug resistance rates to polymyxin B, minocycline, and tigecycline, the drug resistance rates of Acinetobacter baumannii to the other antibiotics were considerably high (80.1%-100.0%). Pseudomonas aeruginosa was not resistant to polymyxin B but highly resistant to netilmicin (88.7%) and piperacillin (92.6%), with resistance rates to the other antibiotics from 34.5% to 62.7%. Klebsiella pneumoniae was not resistant to tigecycline and lowly resistant to imipenem and meropenem (28.9%, 9 imipenem- and meropenem-resistant strains were further confirmed by modified Hodge test), with resistance rates to the other antibiotics from 40.9% to 95.2%. The resistance rates of MRSA to most antibiotics were higher than those of MSSA. MRSA was not resistant to linezolid, vancomycin, teicoplanin, sulfamethoxazole, or tigecycline. The resistance rates of MRSA to clindamycin and erythromycin were 7.9% and 62.0%, respectively, and those to the other antibiotics were higher than 91.5%. Except for the complete resistance to penicillin G and tetracycline, MSSA was not resistant to the other antibiotics. Thirty-three strains of Staphylococcus aureus showed resistance to erythromycin-induced clindamycin. Fungi was not resistant to amphotericin B, with drug resistance rates to voriconazole, itraconazole, ketoconazole, and fluconazole from 4.2% to 6.2%. Conclusions: The incidence of CRBSI and mortality of patients with CRBSI are high in BICU of the author's unit, and the main infection site is femoral vein. There are various types of pathogens in patients with CRBSI, and most of them are Gram-negative. The top three isolated pathogens are Acinetobacter baumannii, Staphylococcus aureus, and Pseudomonas aeruginosa, accompanying with grim drug resistance phenomenon.

Liquid and Dry Swabs for Culture- and PCR-Based Detection of Colonization with Methicillin-Resistant Staphylococcus aureus during Admission Screening.

Rapid detection of methicillin-resistant Staphylococcus aureus (MRSA) colonization status facilitates isolation and decolonization and reduces MRSA infections. Liquid but not dry swabs allow fully automated detection methods. However, the accuracy of culture and polymerase chain reaction (PCR) using liquid and dry swabs has not been analyzed. We compared different swab collection systems for routine nasal–throat MRSA screening in patients admitted to a tertiary care trauma center in Germany. Over 3 consecutive months, dry swabs (month 1), ESwabs (month 2), or MSwabs (month 3) were processed using Cepheid GeneXpert, Roche cobas and BD-MAX™ MRSA tests compared to chromogenic culture. Among 1680 subjects, the MRSA detection rate using PCR methods did not differ significantly between dry swabs, ESwab, and MSwab (6.0%, 6.2%, and 5.3%, respectively). Detection rates using chromogenic culture were 2.9%, 3.9%, and 1.9%, using dry, ESwab, and MSwab, respectively. Using chromogenic culture as the “gold standard”, negative predictive values for the PCR tests ranged from 99.2–100%, and positive predictive values from 33.3–54.8%. Thus, efficient and accurate MRSA screening can be achieved using dry, as well as liquid E- or MSwab, collection systems. Specimen collection using ESwab or MSwab facilitates efficient processing for chromogenic culture in full laboratory automation while also allowing molecular testing in automated PCR systems.

Impact of infection control measures on the related costs and the amount of broad-spectrum antimicrobial agents used in a hospital: A time-series analysis.

Health care-associated infections (HAIs) worsen patient prognoses and increase medical costs. Antimicrobial stewardship (AMS), which involves appropriate use of antimicrobial agents and antiseptics, may be beneficial for addressing the issue of HAIs. In hospitals, an infection control team (ICT) plays an important role on the appropriate use of antimicrobial agents and antiseptics based on AMS. We aimed to conduct a time-series analysis of the efficacies of infection control measures in terms of related costs, amount of broad-spectrum antimicrobial agents used (carbapenems and quinolones), and methicillin-resistant Staphylococcus aureus (MRSA) detection rates. This retrospective cross-sectional study included in-hospital patients treated at a single institute between January 2012 and December 2015. The intervention start point (initiation of infection control measures) was January 2014. All survey items were subjected to segmented regression analysis using an autoregressive integrated moving average (ARIMA) model. Differences between pre-intervention and postintervention levels and their trends were assessed, using a statistical significance cutoff of P < .05. The infection control costs demonstrated a significantly increasing trend, despite significant decreases in the amount of carbapenems used. Accordingly, the implementation of infection control measures was associated with increased costs, whereas carbapenem use decreased immediately after intervention. Postintervention levels, trends of quinolone use, or MRSA detection rates did not reveal significant changes. Although implementation of infection control measures induced gradual increases in related costs, these measures led to immediate reductions in carbapenem use. Our study findings will support the establishment of more effective and economical infection control measures.

Bacteriology and resistance patterns of otitis media with effusion

ObjectivesFollowing the increased use of antibiotics, the emergence of antibiotic-resistant species in pediatric patients with otitis media has become a problem in recent years. The aim of this study was to investigate change in bacterial species, antibiotic resistance, and detection rate of highly pathogenic species, such as Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa according to the number of repeated ventilation tube insertion (VTI) procedures in pediatric patients diagnosed with otitis media with effusion (OME). Materials & methodsFrom May 2010 to June 2018, 158 patients under 17 years of age who were admitted to the outpatient clinic of Kyung Hee Medical Center and diagnosed as OME and underwent unilateral or bilateral VTI were included in this study. Bacterial cultures were performed on aseptically collected middle ear effusion (MEF) at the time of VTI and antibiotic sensitivity tests were performed on the identified bacteria. ResultsBacteria were not identified in 195 (70.1%) cultures and identified in 83 (29.9%) cultures. Coagulase-negative staphylococci (CNS) was the most frequently detected species in both the non-recurrent group and the recurrent group. MRSA detection rate was found to be significantly higher in the recurrent group than in the non-recurrent group (p = 0.029). The two groups showed no significant difference in antibiotic resistance against all antibiotics (p > 0.05). ConclusionStaphylococcus species were detected most frequently in the MEF of pediatric OME patients, and the MRSA detection rate was higher in the recurrent group than in the non-recurrent group. There was no difference in antibiotic sensitivity between the two groups against all antibiotics, but resistance to penicillin G and cefoxitin was newly appeared in patients with repeated detection of same bacterial isolates.

Impact of MRSA Transmission and Infection in a Neonatal Intensive Care Unit in China: A Bundle Intervention Study during 2014-2017.

Objective. To evaluate the efficacy of bundle intervention on healthcare-associated (HA) methicillin-resistant Staphylococcus Aureus (MRSA) infection in the neonatal intensive care unit (NICU). Methods. In this study, 11,277 infants having undergone treatment at the NICU in Xiamen, China, from January 2014 to February 2017 were recruited. We retrospectively reviewed patients' demographic and clinical information. Patients from 2014 to 2015 were treated as the control group and those from 2016 to 2017 were classified as the experimental group. Bundle intervention measures were performed, including screening for MRSA, isolation precautions, training of hand hygiene, cleaning protocols, and decontamination of isolation ward. The HA-MRSA data and compliance of infection control measures between both groups were analyzed. Results. Through bundle interventions, the compliance with the isolation of MRSA raised from 55.88% to 92.86% and hand hygiene compliance increased from 90.07% to 93.23% (P < 0.05). The HA infection decreased from 1.87% to 1.71% (P > 0.05) and HA detection rate of MRSA declined from 2.63‰ to 1.00‰, respectively (P < 0.05). Conclusion. Multifaceted interventions can effectively prevent MRSA infection and transmission; this includes active surveillance, isolation precautions, increased hand hygiene compliance, environmental cleaning, and decontamination.

Epidemiology and risk factors of methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci infections in Zhejiang China from 2015 to 2017

BackgroundGram-positive bacteria are dangerous and challenging agents of infection due to their increasing resistance to antibiotics. We aim to analyse the epidemiology and risk factors of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) in Zhejiang China.MethodsGram-positive bacteria (including S. aureus, Enterococcus faecalis and Enterococcus faecium) were collected from eighty-six hospitals of eleven cities in Zhejiang China from 2015 to 2017. The detection rates of MRSA and VRE infection were calculated for the non-duplicated isolate according to year, region, hospital level, patient age, specimen type and patient category. Meanwhile, the detected resistances of MRSA, E. faecalis and E. faecium to different antibiotics from 2015 to 2017 were compared. The risk factors and the differences in MRSA and VRE detection rates were compared using odds ratio (OR) with 95% confidence interval (95% CI) and Chi-square test respectively.ResultsFrom 2015 to 2017, the detection rates of MRSA and VRE decreased gradually. The cities with the highest MRSA and VRE detection rates tended to be adjacent; for example, the neighbouring cities Hangzhou and Quzhou had simultaneously high rates of MRSA and VRE infection. Patients from IIIA hospital who were older than 75 years and in the intensive care unit (ICU) were most at risk. No vancomycin-resistant isolate was found in MRSA. Resistance of E. faecalis and E. faecium to vancomycin and linezolid decreased slightly and then maintained a low level.ConclusionsThe detection rates of MRSA and VRE stayed at moderate and low levels during the three year period of this study, while local dissemination was found in MRSA and VRE isolates. Sustained surveillance is necessary to prevent the spread or clonal dissemination of drug-resistant strains in Zhejiang China.

Clinical characteristics and prognosis analysis of patient with Methicillin-susceptible Staphylococcus aureus, or Methicillin-resistant Staphylococcus aureus Bacteremia

Objective To investigate the clinical characteristics and prognosis analysis of patient with bacteremia induced by Methicillin-susceptible Staphylococcus aureus (MSSA) or Methicillin-resistant Staphylococcus aureus (MRSA). Methods This retrospective study included 95 Staphylococcus aureus Bacteremia (SAB) patients admitted to Nanjing Drum Tower hospital from January 2012 to December 2017. According to the drug sensitivity tests, patients were divided into MSSA group and MRSA group. Clinical characteristics, systematic score and prognosis were compared between these two group. APACHE Ⅱ score and SOFA score were analyzed by independent-samples t test. The distribution of primary disease and basic disease, bacterium source, and prognostic factors were analyzed by Mann—Whitney U test or χ2 test. The cumulative survival was calculated by the Kaplan-Meier method. Wilcoxon rank sum test was selected for survival rate comparison. Results There are 56 MSSA strain and 39 MRSA strain among the 95 SAB patients, the detection rate is 58.95% and 41.05%, respectively. The most common primary disease of SAB is catheter-related infections(23 cases, 24.21%). Compared with MSSA group, the catheter-related infections has higher detection rate of MRSA obviously (P 0.05). Conclusions The majority of strains in the SAB patients is MSSA. In clinical characteristics, compared with MSSA, MRSA is more common in nosocomial infection, catheter related infection and renal dysfunction patients. There is no significant differences in prognosis between MSSA group and MRSA group. Key words: Staphylococcus aureus; Methicillin-resistant Staphylococcus aureus; Methicillin-susceptible Staphylococcus aureus; Bloodstream infection; Bacteremia; Clinical characteristic; Prognosis; Retrospective analysis

Analysis of drug resistance of Staphylococcus aureus in bone and joint infection in children

Objective To investigate the drug resistance and its changes of Staphylococcus aureus (SA) in children with bone and joint infection caused by hematogenous dissemination in Zunyi area. Methods A retrospective study was performed on the clinical data of 95 cases with bone and joint infections caused by SA from January 2008 to December 2016 in the Affiliated Hospital of Zunyi Medical College, in which there were 53 boys and 42 girls with a mean age of 5.6 years(ranging from 10 days to 14 years), including 39 cases of acute osteomyelitis, 31 cases of acute suppurative arthritis, 19 cases of chronic osteomyelitis, and 6 cases of acute osteomyelitis and arthritis.According to the results of drug sensitivity, the drug resistance of SA was analyzed, and the detection rates of Methicillin resistant Staphylococcus aureus (MRSA) were compared in different genders and timeframes, and the drug resistance of SA to other antibiotics were also analyzed. Results The detection rate of MRSA was 50.53%(48 cases) in 95 cases, the resistance rate to Penicillin was 92.63%(88 cases), and to Lincomycin, Erythromycin, Tetracycline and Cefoxitin were 64.21%(61 cases), 57.90%(55 cases), 55.79%(53 cases) and 53.68%(51 cases) respectively, but to Sulfamethoxazole Co., Gentamicin and Rifampicin it was relatively low[25.26%(24 cases), 11.58%(11 cases), 6.32%(6 cases) respectively], while the resistance to Moxifloxacin, Linezolid, Tigecycline, Vancomycin and Nitrofurantoin was not found.The detection rate of MRSA in boys(52.83%, 28/53 cases) was slightly higher than that of girls(47.62%, 20/42 cases), but the difference was not statistically significant (χ2=0.255, P>0.05). The detection rates of MRSA in 2008-2010, 2011-2013 and 2014-2016 were 27.78%(5/18 cases), 51.61%(16/31 cases) and 58.70%(27/46 cases) respectively, and it was obviously higher in 2014-2016 than in 2008-2010, and the difference was statistically significant (χ2=4.95, P<0.05). The drug resistance rate of SA to Lincomycin, Erythromycin and Cefoxitinis was obviously higher in 2014-2016 than in 2008-2010, and the differences were all statistically significant (all P<0.05). Conclusions The drug resistance of SA is high with the bone and joint infection caused by hematogenous dissemination in children, and the detection rate of MRSA and the drug resistance of SA to a variety of antimicrobial agents are gradually increasing. Key words: Child; Bone and joint infection; Staphylococcus aureus; Drug resistance

Multi-level analysis of bacteria isolated from inpatients in respiratory departments in China.

With the different situation for clinical antibiotic usage and its management in different regions and medical institutions, the antimicrobial resistance varied in different level. However, the epidemiological data of multi-drug resistant (MDR) strains from the department of respiration is limited. Thus, this study aims to investigate the epidemiology of bacteria isolated from inpatients of respiratory departments, and analyze the distribution variation of major multi-drug resistant bacteria in China. Based on data from China Antimicrobial Resistance Surveillance System (CARSS) in 2015, 50,417 non-duplicate isolates obtained from inpatients of respiratory departments from 91 general hospitals in seven regions of China were enrolled in the study. The distribution of methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Escherichia coli (CREC) and Klebsiella pneumoniae (CRKP), carbapenem-resistant Pseudomonas aeruginosa (CRPA) and Acinetobacter baumannii (CRAB), extended-spectrum β-lactamases-producing E. coli (ESBL-EC) and K. pneumoniae (ESBL-KP), were further analyzed by geographic regions, age groups, wards and specimen types. The major specimens type were sputum (81.6%, 41,131/50,417), followed by blood (5.3%, 2,649/50,417), urine (4.5%, 2,249/50,417) and bronchoalveolar lavage fluid (BALF) (3.2%, 1,620/50,417). The top four bacteria species isolated from sputum and BALF were similar: K. pneumonia (18.9% and 14.8%, respectively), P. aeruginosa (13.6% and 22.2%, respectively), A. baumannii (11.3% and 11.9%, respectively) and S. pneumonia (11.1% and 9.6%, respectively). The four most common bacteria species were K. pneumonia (17.2%), P. aeruginosa (12.1%), A. baumannii (10.4%) and S. pneumonia (10.1%) in tertiary hospitals but K. pneumonia (20.8%), P. aeruginosa (16.3%), E. coli (11.3%) and A. baumannii (6.9%) in secondary hospitals. The top four bacteria species in respiratory intensive care unit (RICU) were A. baumannii (25.8%), P. aeruginosa (13.1%), K. pneumonia (12.2%) and S. aureus (9.2%). The prevalence of CRKP, CRPA and CRAB in tertiary hospitals was significantly higher than that in secondary hospitals (5.2% vs. 2.5%, 23.8% vs. 12.8% and 53.5% vs. 33.9%, respectively) (all P<0.05). However, the prevalence of ESBL-EC in secondary hospitals was higher than in tertiary ones (63.9% vs. 55.0%, P=0.011). The prevalence of MRSA, CRKP, CRAB, CRPA, ESBL-EC, ESBL-KP in RICU were higher than that in non-ICU respiratory departments (76.5% vs. 35.7%, 20.1% vs. 4.1%, 90.6% vs. 45.5%, 64.2% vs. 19.3%, 47.2% vs. 28.3% and 43.0% vs. 11.2%, respectively) (all P<0.01). Among seven regions in China, central area had the highest detection rates of MRSA (70.3%, 237/337), CRPA (30.9%, 376/1,218), CRAB (71.8%, 487/678) and ESBL-KP (38.8%, 241/621). The prevalence of ESBL-EC and ESBL-KP in pediatric group (68.2% and 55.3%, respectively) was higher than that in geriatric group (54.2% and 27.1%, respectively) and adult group (51.1% and 15.1%, respectively) (all P<0.001). In China, the predominant bacterial pathogens in the respiratory ward were Enterobacteriaceae and non-fermentative bacteria. High prevalence of ESBL-EC and ESBL-KP isolated from lower respiratory tract (LRT) was revealed in primary hospitals and pediatric patients.