High Rates Of Antibiotic Resistance Research Articles

Comparison of Methicillin-Resistant Staphylococcus aureus Isolates from Cellulitis and from Osteomyelitis in a Taiwan Hospital, 2016-2018.

Methicillin-resistant Staphylococcus aureus (MRSA) causes superficial infections such as cellulitis or invasive infections such as osteomyelitis; however, differences in MRSA isolates from cellulitis (CL-MRSA) and from osteomyelitis (OM-MRSA) at the same local area remain largely unknown. A total of 221 MRSA isolates including 106 CL-MRSA strains and 115 OM-MRSA strains were collected at Chang-Gung Memorial Hospital in Taiwan between 2016 and 2018, and their genotypic and phenotypic characteristics were compared. We found that OM-MRSA isolates significantly exhibited higher rates of resistance to multiple antibiotics than CL-MRSA isolates. Genotypically, OM-MRSA isolates had higher proportions of the SCCmec type III, the sequence type ST239, and the spa type t037 than CL-MRSA isolates. Besides the multidrug-resistant lineage ST239-t037-SCCmecIII more prevalent in OM-MRSA, higher antibiotic resistance rates were also observed in several other prevalent lineages in OM-MRSA as compared to the same lineages in CL-MRSA. Furthermore, when prosthetic joint infection (PJI) associated and non-PJI-associated MRSA strains in osteomyelitis were compared, no significant differences were observed in antibiotic resistance rates between the two groups, albeit more diverse genotypes were found in non-PJI-associated MRSA. Our findings therefore suggest that deep infections may allow MRSA to evade antibiotic attack and facilitate the convergent evolution and selection of multidrug-resistant lineages.

Association between biofilm formation, structure and antibiotic resistance in Staphylococcus epidermidis isolated from neonatal septicemia in southwest Iran.

Background: Staphylococcus epidermidis has emerged as the pathogen from neonatal septicemia. Antibiotic resistance and the capability of biofilm formation make these infections much harder to treat. Hence, the aim of this study was to investigate the association between biofilm formation, structure and antibiotic resistance in S. epidermidis isolated from neonatal septicemia.Methods: Overall, 65 S. epidermidis isolates were recovered from blood cultures of neonatal septicemia. Antibiotic resistance pattern and the biofilm production were determined using phenotypic methods. The presence of ica operon, the bhp, the aap genes and SCCmec types were screened using PCR.Results: Most S.epidermidis isolates were resistant to erythromycin, while all isolates were sensitive to linezolid and vancomycin. Fifty-three percent of S.epidermidis isolates were resistant to methicillin. SCCmec types II was found commonly among methicillin-resistant S. epidermidis (MRSE) strains. The biofilm formation was observed in 65% of S.epidermidis isolates and the majority have polysaccharide matrix. icaA and icaD genes were found in 40% and 19% of isolates. Twenty-three isolates (62%) produced dissolvable polysaccharide intercellular adhesion (PIA)-dependent biofilms in SM after growth in TSB with NaCl and 14 (37%) isolates produced dissolvable protein-dependent biofilms in PK after growth in TSB with glucose. Three isolates (62%) produced dissolvable polysaccharide intercellular adhesion.Conclusion: Our data indicate the high rates of antibiotic resistance and the capability of biofilm formation among S. epidermidis isolates. Hence, the transmission of these strains can cause an increased risk of serious nosocomial infections.

Association of pvl gene with incomplete hemolytic phenotype in clinical Staphylococcus aureus.

Purpose: This experiment aimed to evaluate the correlation between the hemolytic phenotype of Staphylococcus aureus and pvl gene in terms of characteristics of antibiotic resistance.Materials and methods: Two-hundred and eleven strains of hospital-acquired S. aureus and their bacterial susceptibility to 20 antibiotics were determined by MicroScan WalkAway96. All strains were cultured on Columbia sheep blood agar plates for 24 hours and then underwent ten passages for investigation of their hemolytic phenotypes. S. aureus produced incomplete β-hemolytic phenotype, termed as S. aureus strains with incomplete hemolytic phenotype (SIHP). The pvl gene was identified by PCR amplification followed by DNA sequencing. Statistical analyses of the data were performed using SPSS version 16.0 software.Results: Fifty-two (24.64%) strains were confirmed to maintain the incomplete hemolytic phenotype of S. aureus (SIHP). Meanwhile, 15 (7.11%) of 211 strains were found to carry the pvl gene, and eight of the 15 strains were SIHP. Compared with S. aureus strains with complete hemolytic phenotype (SCHP), SIHP showed higher susceptibility to seven of the 20 antibiotics (oxacillin, ciprofloxacin, gentamicin, ceftriaxone, cefoxitin, levofloxacin, and moxifloxacin) (P<0.05). The pvl-positive bacteria had a higher rate of resistance to four antibiotics (rifampin, ciprofloxacin, levofloxacin, and moxifloxacin) in comparison with the pvl-negative strains (P<0.05).Conclusion: SIHP had a high frequency of pvl gene. The pvl-positive isolates showed less resistance to rifampin, ciprofloxacin, levofloxacin, and moxifloxacin. Additionally, the majority of SIHP isolates (61.54%) were methicillin-resistant S. aureus. SIHP strains had significantly higher antibiotic resistance to cefoxitin when compared with SCHP, while SCHP strains had a high rate of antibiotic resistance to ciprofloxacin, gentamicin, ceftriaxone, levofloxacin, and moxifloxacin. The results may help to provide medical advice for selection of antibiotics for patients with SIHP-associated infections.

Multidrug-resistant Shigella infection in pediatric patients with diarrhea from central Iran.

Background: Shigella spp. are primary pathogens of diarrhea in children worldwide. Emergence of resistance to fluoroquinolones and third-generation cephalosporins is crucial in the management of pediatric shigellosis. We determined the prevalence and the antibiotic resistance patterns of Shigella species isolated from pediatric patients in central Iran.Materials and methods: Pediatric diarrhea samples (n=230) were cultured on MacConkey and XLD agar media and in GN broth. Genus-specific PCR for ipaH was also used for detection directly from fecal specimens. Antibiotic resistance and the frequency of ESBL and AmpC genes were determined.Results: Out of the 230 samples, 19 (8.2%) cases of Shigella spp. were identified using culture. Twenty-six samples were positive by PCR (11.3%), S. flexneri (4/19; 21%) and S. sonnei (15/19; 78.9%) being the most detected. The highest antibiotic resistance rates were found for cotrimoxazole (19/19; 100%), ampicillin (16/19; 84.2%), cefixime (13/19; 68.4%) and ceftriaxone (12/19; 63.1%). Ten cases showed phenotypic ESBL presence and all these strains were positive for blaTEM, blaCTX-M-1, and blaCTX-M-15. Three strains were AmpC positive, all of which harbored blaCMY-2 and two contained blaCIT. Of the 19 Shigella isolates 5 (26.3%), 2 (10.5%), and 1 (5.2%) were phenotypically resistant to nalidixic acid, ciprofloxacin, and norfloxacin, respectively. Class 1 integron was found in 18 (94.7%) isolates whereas class 2 integron was found in 19 (100%) strains.Conclusion: We found a considerable presence of Shigella species with elevated antibiotic resistance levels. In particular, the resistance to third-generation cephalosporins (ESBL) and ciprofloxacin must be taken seriously.

Quinolone and Macrolide-Resistant Campylobacter jejuni in Pediatric Gastroenteritis Patients from Central Iran.

Aims: To determine the prevalence and the antibiotic resistance patterns of Campylobacter jejuni isolated from pediatric diarrhea patients in central Iran. Materials and Methods: Stool specimens (n = 230) were investigated using a modified Gram stain, two specific culture media, and C. jejuni-specific PCR. Antibiotic resistance profiles and relevant resistance genes were determined. Genetic relationships among a selection of the isolates were studied by Fla typing. Results: Out of the 230 diarrhea samples, 48 (20.8%) cases of C. jejuni were identified using modified Gram stain, 45 (19.5%) using the culture media, and 76 (33%) cases were identified using PCR. The highest antibiotic resistance rates were observed in 37 (82.2%) strains against tetracycline, in 32 (71.1%) against ciprofloxacin, and in 31 (68.8%) against erythromycin. Twenty (44.4%) isolates were resistant to ciprofloxacin and erythromycin simultaneously. Genotypic investigations found 36 (97.3%) strains carrying the tet (o) gene, 31 (96.8%) harboring the cmeB gene, 22 (68.7%) strains with the gyrA6 gene, 20 (64.5%) strains containing a 23S rRNA mutation, and 21 (65.6%) strains with the qnrS gene. Fla typing of a random subset of 14 strains revealed 11 different types showing the genomic diversity of the isolates. Strains sharing the same Fla type could be easily distinguished by their resistance gene profile. Conclusions: This is the first study to demonstrate that genetically diverse quinolone-macrolide-resistant C. jejuni is an important cause of gastroenteritis in children from central Iran. Pediatricians should consider these resistance features once the antibiotic prescription is necessary for prevention of possible complications, especially in those under 5 years of age. Of note, most cases of Campylobacter diarrhea are self-limiting and antibiotics should only be prescribed in those cases where severe complications evolve.

A randomised controlled trial of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDITOF-MS) versus conventional microbiological methods for identifying pathogens: Impact on optimal antimicrobial therapy of invasive bacterial and fungal infections in Vietnam

We assessed the impact of MALDITOF-MS on the timeliness of optimal antimicrobial therapy through a parallel-arm randomised controlled trial in two hospitals in Vietnam. We recruited patients with a pathogen (bacterial or fungal) cultured from a normally sterile sample. Samples were randomly assigned (1:1) to identification by MALDITOF-MS or conventional diagnostics. The primary outcome was the proportion on optimal antimicrobial therapy within 24 h of positive culture, determined by a blinded independent review committee. Trial registered at ClinicalTrials.gov (NCT02306330). Among 1005 randomised patients, pathogens were isolated from 628 (326 intervention, 302 control), with 377 excluded as likely contaminants or discharged/died before positive culture. Most isolates were cultured from blood (421/628, 67.0%). The proportion receiving optimal antimicrobial therapy within 24 h (the primary outcome) or 48 h of growth was not significantly different between MALDITOF-MS and control arms (135/326, 41.4% vs 120/302, 39.7%; Adjusted Odds ration (AOR) 1.17, p = 0.40 and 151/326, 46.3% vs 141/302, 46.7%; AOR 1.05 p = 0.79, respectively). MALDITOF-MS, in the absence of an antimicrobial stewardship programme, did not improve the proportion on optimal antimicrobial therapy at 24 or 48 h after first growth in a lower-middle income setting with high rates of antibiotic resistance.

Salmonella Typhi From Blood Cultures in the Democratic Republic of the Congo: A 10-Year Surveillance

BackgroundThis study gives an overview of a decade (2007–2017) of hospital-based Salmonella Typhi bloodstream infection (BSI) surveillance in the Democratic Republic of the Congo (DRC), at 4 main sampling sites.MethodsBlood cultures were sampled in hospital-admitted patients with suspected BSI, according to standardized clinical indications. The results of the surveillance period 2015–2017 were compiled with those of previous surveillance periods (2007–2010 and 2011–2014). Whole genome sequencing of isolates with decreased ciprofloxacin susceptibility (DCS) was performed.Results Salmonella Typhi was isolated in 1.4% (531/37 388) and 10.3% (531/5177) of suspected and culture-confirmed BSI episodes, respectively. Salmonella Typhi ranked first among the BSI pathogens in adults (n = 220), but was mostly (n = 301 [56.7%]) isolated from children, of which 72.1% (217/301) and 31.6% (95/301) were <10 years and <5 years old, respectively. Multidrug resistance (MDR), DCS, and combined MDR/DCS were found in 38.3% (n = 180), 24.5% (n = 115), and 11.9% (n = 56) of 470 first isolates, respectively. MDR and DCS rates had increased since 2007, but remained stable during 2015–2017 with no geographical clustering at the province level. Most (91/93 [97.8%]) DCS isolates sequenced belonged to Genotyphi genotype 2.5.1, and gyr S83 was the most frequent DCS mutation (76/93 [81.7%]). Infections occurred perennially, but increased during the rainy season.Conclusions Salmonella Typhi was a frequent cause of BSI in adults and children in DRC, with high rates of antibiotic resistance. Sustainable surveillance and implementation of vaccination are compelling.

Prevalence and antibiotic susceptibility of bacterial pathogens at a tertiary care hospital in Nablus, occupied Palestinian territory: a cross-sectional survey

BackgroundThe increasing incidence of hospital-acquired infections caused by antibiotic-resistant pathogens has led to an increase in morbidity and mortality worldwide. The aim of this study was to assess the frequency and antibiotic susceptibility of bacterial pathogens isolated at An-Najah National University Hospital (NNUH) in Nablus city in the occupied Palestinian territory during 2015. MethodsA retrospective study was conducted of all positive bacterial cultures obtained from the microbiology laboratory of NNUH. Results of culture and sensitivity of patients' specimens were analysed. Approval was obtained from the institutional review board of An-Najah National University. FindingsOf the 4421 cultures processed, 1335 (30·2%) were positive. 621 (46·4%) bacterial isolates were Gram-positive, 565 (42·3%) were Gram-negative organisms and 151 (11·3%) were Candida species. The most frequent Gram-positive organisms were coagulase-negative Staphylococci (CoNS) and Enterococcus species, followed by Staphylococcus aureus (50·2%, 25·0%, and 14·8%, respectively). Enterococcus coli was the most frequent Gram-negative organism followed by Klebsiella pneumonia, Acinetobacter baumannii, and Pseudomonas aeroginosa (28·3%, 21·0%, 18·4%, and 18·4%, respectively). CoNS showed high resistance to oxacillin (89%) and erythromycin (74·6%). Enterococcus spp had the highest resistance to clindamycin (93·5%), followed by tetracycline (85·7%), and erythromycin (74·6%). S aureus isolates were resistant to oxacillin (56·0%) and erythromycin (52·0%). E coli showed high resistance to ampicillin (90·1%), ceftriaxone (77·0%), fluoroquinolones (eg, ciprofloxacin; 75·0%), and erythromycin (70·2%). K pneumoniae was mostly resistant to ampicillin (100·0%), aztreonam (83·3%), and third generation cephalosporins (ceftriaxone, 80·9%; ceftazidime, 78·2%; and cefotaxime, 77·2%). Pseudomonas aeruginosa showed high resistance to tigecycline (95·4%), ceftriaxone (94·1%), and cefotaxime (95·4%). A baumannii was resistant to all tested antibiotics—including amikacin, cephalosporins, fluoroquinolones, and carbapenems—except tetracycline. InterpretationThe high rates of antibiotic resistance are a cause for concern. Similar studies should be carried out at all hospitals in Palestine in an effort to control the development of antibiotic resistance and the spread of these multidrug-resistant organisms. FundingAn-Najah National University.

Increase in antibiotic resistant Helicobacter pylori in a University Hospital in Japan.

BackgroundEradication effectively prevents Helicobacter pylori-associated diseases; however, H. pylori antibiotic resistance has increased throughout Japan and worldwide. This study aimed to assess rates of resistance to antibiotics; amoxicillin, clarithromycin and metronidazole in a University Hospital in Japan.Materials and methodsH. pylori (208 strains) were isolated from patients at the Okayama University Hospital in Japan. The minimum inhibitory concentrations (MIC) were determined using the mean values of the E-test to determine the antimicrobial susceptibilities of the strains. Sequencing and gene analysis were performed to analyze resistance genes to clarithromycin and amoxicillin.ResultsRates of amoxicillin, clarithromycin, and metronidazole resistance were 13%, 48%, and 49%, respectively. Genetic analysis indicated that the A2143G point mutation in 23S rDNA is closely associated with the MIC of clarithromycin. The MIC in amoxicillin-resistant strains increased with an increase in the number of PBP1A amino acids mutations.ConclusionGenetic analysis for resistant strains is not clinically effective in cases of amoxicillin resistance. Numerous bacteria with already high antibiotic resistance rates have been isolated in large hospitals such as a University Hospital. For effective eradication therapy, MIC measurement should be considered via several methods.

A 5-year surveillance on antimicrobial resistance of Acinetobacter isolates at a level-I trauma centre of India.

INTRODUCTION:Acinetobacter spp. has emerged as a major cause of nosocomial outbreaks. Multiple antibiotic resistance is an important problem in Acinetobacter isolates in recent years. The aim of this study was to evaluate the rate of antimicrobial resistance and changes in resistance pattern over a period of 5 years (2012–2016) in Acinetobacter spp. isolated from trauma patients.MATERIALS AND METHODS:Acinetobacter spp. was identified by VITEK 2 and antibiotic susceptibility of isolates was investigated by disc-diffusion method and VITEK 2 automated system. Interpretation of susceptibility results was based on the Clinical and Laboratory Standards Institute guidelines.RESULTS:Out of the total 16,210 isolates obtained throughout the period of 5 years, Acinetobacter spp. accounted for 3744 (28.9%). Out of which, the species which was maximally isolated was Acinetobacter baumannii (98.5%), followed by Acinetobacter lwoffii (1.4%) and Acinetobacter hemolyticus (0.1%). The highest number of clinical isolates of Acinetobacter were recovered from neurosurgical ward (n = 1210), followed by the neurosurgical intensive care unit (ICU) (n = 1000) and surgical ICU (n = 948) and the most common sample of Acinetobacter isolation was from tracheal aspirate (37.1%), followed by wound swab (18.8%). The highest level of resistance was observed against ciprofloxacin (96%), followed by cefepime (95%), ceftazidime (95%), piperacillin (95%), and amikacin (92%). The trend of antibiotic resistance was found to be statistically significant (P < 0.001) for most of the antibiotics being tested such as amikacin and carbapenems.CONCLUSION:The high rate of antibiotic resistance of the Acinetobacter strains indicated that there is an urgent need for controlled antibiotic usage and appliance of hospital infection control measures.

Eradication Rates of 10-day Sequential Therapy for Helicobacter pylori: Results of an 8-year Prospective Study Conducted at a Tertiary Korean Hospital

The Helicobacter pylori (H. pylori) eradication rate of standard triple therapy is unsatisfactory in Korea, and sequential therapy (SQT) has been suggested to be a practical first-line alternative regimen. The aim of this prospective study was to document changes in annual eradication rates of SQT. A total of 983 H. pylori-positive subjects were enrolled from 2010 to 2018 and their data were subjected to intention-to-treat (ITT) and per-protocol (PP) analysis. All subjects received 10-day sequential therapy consisting of 40 mg esomeprazole and 1 g amoxicillin b.i.d for 5 days followed by 40 mg esomeprazole b.i.d, 500 mg clarithromycin b.i.d and 500 mg metronidazole t.i.d for 5 days. The 13C-urea breath test, rapid urease test (CLO test®), and histology were used to confirm eradication. Compliance and side effects were also investigated. ITT and PP eradication rates of SQT were 69.9% (687 of 983) and 87.1% (657 of 754), respectively. The annual eradication rate of ITT remained consistent over the 8-year study period (p for trend=0.167), whereas PP analysis showed the eradication rate increased (p for trend=0.042). The overall adverse event rate for SQT was 41.7% (410 subjects). Despite high antibiotic resistance rates in Korea, the eradication rate of SQT did not decrease over the 8-year study period.

Prevalence and antibiotic resistance pattern of extended-spectrum beta-lactamase-producing Escherichia coli in clinical specimens

Background:Extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae seem to have an extended antibiotic resistance, but have different resistance patterns throughout different sites and regions. This study aimed to evaluate the antibiotic resistance pattern of ESBL-producing Escherichia coli.Materials and Methods:One hundred swab samples from patients hospitalized due to a clinical suspicion of any kind of infection (with manifestations such as fever, leukocytosis, and an active urinalysis result) were processed in Alzahra Microbiology Laboratory, Isfahan, Iran. Isolated E. coli were cultured on Mueller–Hinton agar and antibiotic susceptibility was tested by Kirby–Bauer disk diffusion method following the Clinical and Laboratory Standard Institute 2017 guidelines.Results:ESBL-producing samples had higher antibiotic resistance rates than ESBL-non-producing samples: ceftriaxone (58.8% vs. 27.3%), cefotaxime (73.5% vs. 30.3%), ceftizoxime (76.5% vs. 33.3%), cefixime (79.4% vs. 40.9%), and cefpodoxime (73.5% vs. 53%), except for carbenicillin (29.4% vs. 48.5%). Imipenem and meropenem were the least resisted antibiotics in ESBL-producing samples (5.9% and 11.8%).Conclusion:ESBL-producing Enterobacteriaceae have a high resistance rate to third-generation cephalosporins and high susceptibility to imipenem and meropenem.

Haemophilus Species Isolated in Urethral Exudates as a Possible Causative Agent in Acute Urethritis: A Study of 38 Cases

IntroductionThe incidence of urethritis due to Haemophilus species is increasing. The main aim of this study was to describe the clinical and microbiological characteristics of patients with this form of urethritis. A secondary aim was to discuss the adequacy of treatments in patients with different types of antibiotic resistance. Material and methodsWe studied patients with a microbiologically confirmed diagnosis of urethritis seen at the Sexually Transmitted Infections Unit of our hospital between July 2015 and July 2018. We selected all patients in whom Haemophilus species were isolated on chocolate agar. Antibiotic resistance was tested using the disk-diffusion method. Cross-sectional data were collected prospectively during outpatient visits. ResultsHaemophilus species were isolated in 33.6% of cases. The most common clinical manifestation was urethral discharge (57.6%); 60% of the patients were men who have sex with men and in this subgroup Haemophilus species were significantly more common than either Neisseria or Chlamydia species. Haemophilus species were found in isolation in 39.5% of patients and the most common one was Haemophilus parainfluenzae (isolated in 84.2% of cases). In total, 34.2% of patients were resistant to azithromycin and 26.3% were resistant to both azithromycin and tetracycline. Empirical treatment achieved clinical and microbiologic cure in 11 of the patients who were not lost to follow-up (n=17; 44.7%). The remaining 6 patients required treatment with a new antibiotic. ConclusionsHaemophilus species are a new cause of nongonococcal urethritis, whose incidence is rising, particularly in men who have sex with men who engage in unprotected oral sex. The clinical manifestations are similar to those seen in gonococcal urethritis. Eradication of infection must be confirmed due to the high rate of antibiotic resistance associated with Haemophilus species.

High rate of antibiotic resistance among pneumococci carried by healthy children in the eastern part of the Democratic Republic of the Congo

BackgroundPneumococcal conjugate vaccines have been introduced in the infant immunisation programmes in many countries to reduce the rate of fatal pneumococcal infections. In the Democratic Republic of the Congo (DR Congo) a 13-valent vaccine (PCV13) was introduced in 2013. Data on the burden of circulating pneumococci among children after this introduction are lacking. In this study, we aimed to determine the risk factors related to pneumococcal carriage in healthy Congolese children after the vaccine introduction and to assess the antibiotic resistance rates and serotype distribution among the isolated pneumococci.MethodsIn 2014 and 2015, 794 healthy children aged one to 60 months attending health centres in the eastern part of DR Congo for immunisation or growth monitoring were included in the study. Data on socio-demographic and medical factors were collected by interviews with the children’s caregivers. Nasopharyngeal swabs were obtained from all the children for bacterial culture, and isolated pneumococci were further tested for antimicrobial resistance using disc diffusion tests and, when indicated, minimal inhibitory concentration (MIC) determination, and for serotype/serogroup by molecular testing.ResultsThe pneumococcal detection rate was 21%, being higher among children who had not received PCV13 vaccination, lived in rural areas, had an enclosed kitchen, were malnourished or presented with fever (p value < 0.05). The predominant serotypes were 19F, 11, 6A/B/C/D and 10A. More than 50% of the pneumococcal isolates belonged to a serotype/serogroup not included in PCV13.Eighty per cent of the isolates were not susceptible to benzylpenicillin and non-susceptibility to ampicillin and ceftriaxone was also high (42 and 37% respectively). Almost all the isolates (94%) were resistant to trimethoprim-sulphamethoxazole, while 43% of the strains were resistant to ≥3 antibiotics.ConclusionsOur study shows alarmingly high levels of reduced susceptibility to commonly used antibiotics in pneumococci carried by healthy Congolese children. This highlights the importance of local antibiotic resistance surveillance and indicates the needs for the more appropriate use of antibiotics in the area. The results further indicate that improved living conditions are needed to reduce the pneumococcal burden, in addition to PCV13 vaccination.

Distribution and drug resistance of pathogenic bacteria in ventilator-associated pneumonia at a local hospital of North-eastern China

PurposeTo study the distribution of pathogenic bacteria in ventilator-associated pneumonia (VAP), and epidemiological characteristics of extended-spectrum β lactamase (ESBL)-producing bacteria.Patients and methodsLower respiratory tract secretions from 156 patients with mechanical ventilation were collected using a protective specimen brush (PSB), with quantitative bacterial culture carried out and antibiotic sensitivity measured. ESBLs produced by Gram-negative bacilli were detected using the double disk diffusion method and monitored by plasmid profiles.ResultsGram-negative bacilli accounted for 78.9% of VAP pathogens, with Acinetobacter baumannii (25%), Pseudomonas aeruginosa (19.7%), and Klebsiella pneumoniae (14.5%) as the most common strains. There were 12 Gram-positive strains detected (15.8%); mostly methicillin-resistant. Staphylococcus aureus and methicillin-resistant coagulase-negative Staphylococcus. There were also four strains of Candida albicans detected (5.26%). Most Gram-negative bacilli are sensitive to imipenem, but A. baumannii is serious resistant. ESBLs were detected in nine strains of Gram-negative bacilli; mainly produced by K. pneumoniae and Escherichia coli, to different degrees of multidrug resistance. Five strains of K. pneumoniae-producing ESBLs were from the same clonal origin, as confirmed by plasmid restriction endonuclease analysis.ConclusionVAP was mainly caused by Gram-negative bacteria, with high antibiotic resistance rates. Plasmids played an important role in the spread of antibiotic resistance among bacteria.

Aislamiento de Haemophilus spp. en exudados uretrales como posible agente etiológico de uretritis aguda: estudio de 38 casos

IntroductionThe incidence of urethritis due to Haemophilus species is increasing. The main aim of this study was to describe the clinical and microbiological characteristics of patients with this form of urethritis. A secondary aim was to discuss the adequacy of treatments in patients with different types of antibiotic resistance. Material and methodsWe studied patients with a microbiologically confirmed diagnosis of urethritis seen at the Sexually Transmitted Infections Unit of our hospital between July 2015 and July 2018. We selected all patients in whom Haemophilus species were isolated on chocolate agar. Antibiotic resistance was tested using the disk-diffusion method. Cross-sectional data were collected prospectively during outpatient visits. ResultsHaemophilus species were isolated in 33.6% of cases. The most common clinical manifestation was urethral discharge (57.6%); 60% of the patients were men who have sex with men and in this subgroup Haemophilus species were significantly more common than either Neisseria or Chlamydia species. Haemophilus species were found in isolation in 39.5% of patients and the most common one was Haemophilus parainfluenzae (isolated in 84.2% of cases). In total, 34.2% of patients were resistant to azithromycin and 26.3% were resistant to both azithromycin and tetracycline. Empirical treatment achieved clinical and microbiologic cure in 11 of the patients who were not lost to follow-up (n=17; 44.7%). The remaining 6 patients required treatment with a new antibiotic. ConclusionsHaemophilus species are a new cause of nongonococcal urethritis, whose incidence is rising, particularly in men who have sex with men who engage in unprotected oral sex. The clinical manifestations are similar to those seen in gonococcal urethritis. Eradication of infection must be confirmed due to the high rate of antibiotic resistance associated with Haemophilus species.

Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD).

Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD).

Identification and antibiotic susceptibility of lactobacilli isolated from turkeys

BackgroundThe aim of this study was to identify Lactobacillus isolates derived from turkeys from six Polish farms and to characterize their phenotypic and genotypic antibiotic resistance profiles.ResultsAmong 62 isolates identified by MALDI-TOF mass spectrometry and restriction analysis of 16S rDNA, the dominant species was L. salivarius (35%), followed by L. crispatus (21%), L. ingluviei (14.5%) and L. johnsonii (10%). A high prevalence of resistance to tetracycline (68% resistant isolates), lincomycin (64.5%) and enrofloxacin (60%) among the lactobacilli tested was observed. Fewer than 50% isolates were resistant to ampicillin (47%), erythromycin (45%), streptomycin (31%), chloramphenicol (29%) and gentamicin (10%). As many as 64,5% of the isolates showed multidrug resistance. High MIC values for ampicillin (≥64 μg/ml) were usually accompanied by elevated MICs for cephalosporins (≥16 μg/ml) and high MICs for tiamulin, i.e. ≥32 μg/ml, were noted in most of the turkey lactobacilli (61%). The occurrence of resistance genes was associated with phenotypic resistance, with the exception of five phenotypically susceptible isolates that contained the tetM, tetL, ermC, ermB or cat genes. The most frequently identified were ermB (45% isolates), tetL (40%), tetW (37%) and tetM (29%), and the occurrence of lnuA (18%), cat (10%), ermC (6%), ant(6)-Ia (5%) and aadE (5%) was less frequent. The mechanism of ampicillin resistance has not been elucidated, but the results of nitrocefin test confirmed that it is not involved in the production of beta-lactamases.ConclusionsThe high rate of antibiotic resistance observed in this study indicates the need to implement the principles of rational use of antibiotics in poultry. The presence of transmissible resistant genes in lactobacilli may contribute to the development of antibiotic resistant pathogenic strains that pose a threat to both poultry and consumers. The results of these studies may be useful for committees providing guidance on antibiotic susceptibility of microorganisms in order to revise and supplement current microbiological cut-offs values within the genus Lactobacillus.

Diagnostic ability and inappropriate antibiotic prescriptions: a quasi-experimental study of primary care providers in rural China.

China has one of the highest rates of antibiotic resistance. Existing studies document high rates of antibiotic prescription by primary care providers but there is little direct evidence on clinically inappropriate use of antibiotics or the drivers of antibiotic prescription. To assess clinically inappropriate antibiotic prescriptions among rural primary care providers, we employed unannounced standardized patients (SPs) who presented three fixed disease cases, none of which indicated antibiotics. We compared antibiotic prescriptions of the same providers in interactions with SPs and matching vignettes assessing knowledge of diagnosis and treatment to assess overprescription attributable to deficits in diagnostic knowledge, therapeutic knowledge and factors that lead providers to deviate from their knowledge of best practice. Overall, antibiotics were inappropriately prescribed in 221/526 (42%) SP cases. Compared with SP interactions, prescription rates were 29% lower in matching clinical vignettes (42% versus 30%, P < 0.0001). Compared with vignettes assessing diagnostic and therapeutic knowledge jointly, rates were 67% lower in vignettes with the diagnosis revealed (30% versus 10%, P < 0.0001). Antibiotic prescription in vignettes was inversely related to measures of diagnostic process quality (completion of checklists). Clinically inappropriate antibiotic prescription is common among primary care providers in rural China. While a large proportion of overprescription may be due to factors such as financial incentives tied to drug sales and perceived patient demand, our findings suggest that deficits in diagnostic knowledge are a major driver of unnecessary antibiotic prescriptions. Interventions to improve diagnostic capacity among providers in rural China are needed.

Highly Prevalent Multidrug-Resistant Salmonella From Chicken and Pork Meat at Retail Markets in Guangdong, China.

This study aimed to investigate the prevalence, serotype distribution, and antibiotic resistance, and to characterize the extended spectrum β-lactamases (ESBLs) producing Salmonella isolates from chicken and pork meats from retail markets in Guangdong province, China. A total of 903 retail meat samples (475 chicken and 428 pork meats) were obtained from six cities (Guangzhou, Shenzhen, Heyuan, Shaoguan, Foshan, and Yunfu) of Guangdong province between May 2016 and April 2017. High levels of Salmonella contamination were detected in chicken (302/475, 63.6%) and pork (313/428, 73.1%). Thirty-eight serotypes were identified in 615 detected Salmonella, and the serotypes varied greatly between chicken and pork samples. Agona (55/302, 18.2%), Corvallis (45/302, 14.9%), Kentucky (38/302, 12.6%), Mbandaka (32/302, 10.6%) was the dominant serotypes in chicken samples. However, Typhimurium (78/313, 24.9%), Rissen (67/313, 24.1%), Derby (66/313, 21.1%), and London (48, 15.3%) were the most common in pork samples. High rates of antibiotic resistance were found to sulfisoxazole (468/615, 76.1%), tetracycline (463/615, 75.3%), ampicillin (295/615, 48.0%), and ofloxacin (275/615, 44.7%). Notably, antimicrobial susceptibility tests identified resistance to polymyxin B (12/615, 2.0%) and imipenem (3/615, 0.5%). Multidrug-resistance (MDR) was detected in Salmonella isolated from chicken (245/302, 81.1%) and pork (229/313, 73.2%). The resistance rate of different Salmonella serotypes varied widely. Especially, isolates such as Typhimurium, Agona, Corvallis and Kentucky exhibited highly resistance to antibiotics. The MDR rate of Salmonella isolates from chicken was significantly higher than that from pork isolates (P < 0.05). Twenty-one Salmonella isolates were identified as ESBLs-producing, covering six Salmonella serotypes and displaying different pulse field gel electrophoresis (PFGE) genotypes. BlaOXA-1 was the dominant ESBLs gene (9/21, 42.9%), followed by blaCTX-M-55 (5/21, 23.8%). This study indicated that Salmonella was widespread in chicken and pork from retail markets in Guangdong province and the isolates showed high multidrug-resistance, especially the known multidrug-resistant Salmonella serotypes. Therefore, it is important to focus on Salmonella serotypes and strengthen the long-term monitoring of MDR Salmonella serotypes in animal-derived foods.