Unnecessary antibiotic use in men who have sex with men (MSM) with anogenital symptoms attending a sexual health clinic: a retrospective analysis.

OBJECTIVES: To quantify the amount of unnecessary antibiotics, in particular ceftriaxone, given to men who have sex with men (MSM) with anogenital symptoms as part of presumptive management in an urban sexual health clinic and examine factors associated with unnecessary ceftriaxone. METHODS: This is a retrospective cross-sectional analysis of electronic records from all visits involving MSM reporting symptoms of bacterial sexually transmitted infection (STI) and who received presumptive antibiotics at Sydney Sexual Health Centre. The following variables were extracted: demographic and sexual behaviour data, presenting symptoms, prior STI diagnoses, use of anoscopy, use of point-of-care microscopy, prescriptions of antibiotics and subsequent nucleic acid amplification testing (NAAT) results for chlamydia and gonorrhoea in all anatomical sites (urethra, pharynx and rectum). We defined unnecessary antibiotic as an agent prescribed to treat an STI organism that was subsequently not detected. RESULTS: Among 1061 visits in this analysis, 41.8% yielded negative NAAT results for both chlamydia and gonorrhoea in all anatomical sites. There were 44.3% of visits which had positive gonorrhoea NAAT result in at least one anatomical site. There were 187 courses of ceftriaxone prescribed in patients who tested negative for gonorrhoea in all anatomical sites and therefore were unnecessary. Unnecessary ceftriaxone prescribing occurred in 50.2% of visits with anorectal symptoms, 19.6% of scrotal symptoms and 7.3% of urethral symptoms. Microscopy was associated with significantly less unnecessary ceftriaxone in urethral but not anorectal or scrotal presentations. In multivariable analysis, the following factors were associated with a higher likelihood of unnecessary ceftriaxone use: anorectal symptoms, scrotal symptoms, gonorrhoea in the preceding year, contact of a bacterial STI and living with HIV. CONCLUSIONS: This study highlights the significant amount of unnecessary ceftriaxone used for STI symptoms in MSM. A new pathway incorporating rapid point-of-care molecular testing in symptomatic patients may improve the precision of antibiotic prescribing and reduce unnecessary use.

Molecular detection of ceftriaxone resistance in Neisseria gonorrhoeae clinical specimens: a tool for public health control.

OBJECTIVES: This study aimed to validate and implement a rapid screening assay for molecular detection of the penA-60 allele that is associated with ceftriaxone resistance in Neisseria gonorrhoeae for use on both isolate lysates and clinical specimen DNA extracts. METHODS: A N. gonorrhoeae penA real-time (RT)-PCR was adapted to include a species-specific pap confirmation target and a commercially available internal control to monitor for PCR inhibition.The modified assay was validated using N. gonorrhoeae-positive (n=24) and N. gonorrhoeae-negative (n=42) clinical specimens and isolate lysates. The panel included seven samples with resistance conferred by penA alleles targeted by the assay and four samples with different penA alleles. The feasibility of using the penA RT-PCR for molecular surveillance was assessed using clinical specimens from 54 individuals attending a London sexual health clinic who also had a N. gonorrhoeae isolate included in the 2020 Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP). RESULTS: The assay correctly identified N. gonorrhoeae specimens (n=7) with penA-60/64 alleles targeted by the assay. No penA false negatives/positives were detected, giving the penA target of the assay a sensitivity, specificity, positive and negative predicted values (PPV, NPV) of 100% (95% CIs; sensitivity; 56.1-100%, specificity; 93.6-100%, PPV; 56.1-100%, NPV; 93.6-100%).No cross-reactivity with other Neisseria species or other urogenital pathogens was detected. The N. gonorrhoeae target (pap) was detected in 73 out of 78 of the N. gonorrhoeae-positive specimens, resulting in 92.6% sensitivity (95% CI 83.0% to 97.3%), 100% specificity (95% CI 75.9% to 100%) and PPV, and a NPV of 89.4% (95% CI 52.5% to 90.9%). No penA-59/60/64 alleles were detected within the clinical specimens from the GRASP 2020 feasibility molecular surveillance study (n=54 individuals). CONCLUSION: The implementation of this PCR assay for patient management, public health and surveillance purposes enables the rapid detection of gonococcal ceftriaxone resistance conferred by the most widely circulating penA alleles.

Clinical scoring model for predicting cefotaxime-resistance in Klebsiella pneumoniae bacteremia: development and validation based on portal of entry.

We developed a prediction model for cefotaxime resistance in patients with K. pneumoniae bacteremia. Adult patients with K. pneumoniae bacteremia were grouped into derivation (from March 2018 to December 2019) and validation (from January 2020 to August 2020) cohorts. The prediction scoring system was based on factors associated with cefotaxime resistance identified by the logistic regression model. A total of 358 patients were enrolled (256 for derivation, 102 for validation). In the multivariable analysis, age ≥65 years, hospital-acquired infection, prior antimicrobial use, and an updated Charlson comorbidity index ≥3 points were associated with cefotaxime resistance in the derivation cohort. When each variable was counted as 1 point, the values of the area under the curve were 0.761 in the derivation and 0.781 in the validation cohorts. The best cutoff value using the Youden index was ≥2 with 73.6% sensitivity and 67.5% specificity. Our simple scoring system favorably predicted cefotaxime resistance.

Impact of molecular ciprofloxacin resistance testing in management of gonorrhoea in a large urban clinic.

OBJECTIVES: Antibiotic resistance in gonorrhoea is of significant public health concern with the emergence of resistance to last-line therapies such as ceftriaxone. Despite around half of Neisseria gonorrhoeae isolates tested in the UK being susceptible to ciprofloxacin, very little ciprofloxacin is used in clinical practice. Testing for the S91F mutation associated with ciprofloxacin resistance is now available in CE-marked assays and may reduce the requirement for ceftriaxone, but many patients are treated empirically, or as sexual contacts, which may limit any benefit. We describe the real-world impact of such testing on antimicrobial use and clinical outcomes in people found to have gonorrhoea in a large urban UK sexual health clinic. METHODS: Molecular ciprofloxacin resistance testing (ResistancePlus GC assay (SpeeDx)) was undertaken as an additional test after initial diagnosis (m2000 Realtime CT/NG assay (Abbott Molecular)) in those not already known to have had antimicrobial treatment. Data from a 6-month period (from March to September 2022) were analysed to determine treatment choice and treatment outcome. RESULTS: A total of 998 clinical samples tested positive for N. gonorrhoeae in 682 episodes of infection. Of the 560 (56%) samples eligible for resistance testing, 269 (48.0%) were reported as wild-type, 180 (32.1%) were predicted to be resistant, 63 (11.3%) had an indeterminate resistance profile, and in 48 (8.6%) samples, N. gonorrhoeae was not detected. Ciprofloxacin was prescribed in 172 (75%) of 228 episodes in which the wild-type strain was detected. Four (2%) of those treated with ciprofloxacin had a positive test-of-cure sample by NAAT, with no reinfection risk. All four had ciprofloxacin-susceptible infection by phenotypic antimicrobial susceptibility testing. CONCLUSIONS: In routine practice in a large UK clinic, molecular ciprofloxacin resistance testing led to a significant shift in antibiotic use, reducing use of ceftriaxone. Testing can be targeted to reduce unnecessary additional testing. Longer term impact on antimicrobial resistance requires ongoing surveillance.

Minimum inhibitory concentrations of Neisseria gonorrhoeae strains in clients of the Amsterdam sexual health clinic with a Dutch versus an international sexual network.

OBJECTIVES: International travel combined with sex may contribute to dissemination of antimicrobial-resistant (AMR) Neisseria gonorrhoeae (Ng). To assess the role of travel in Ng strain susceptibility, we compared minimum inhibitory concentrations (MICs) for five antibiotics (ie, azithromycin, ceftriaxone, cefotaxime, cefixime and ciprofloxacin) in strains from clients with an exclusively Dutch sexual network and clients with an additional international sexual network. METHODS: From 2013 to 2019, we recorded recent residence of sexual partners of clients (and of their partners) with Ng at the Center for Sexual Health of Amsterdam. We categorised clients as having: (1) exclusively sexual partners residing in the Netherlands ('Dutch only') or (2) at least one partner residing outside the Netherlands. We categorised the country of residence of sexual partners by World Bank/EuroVoc regions. We analysed the difference of log-transformed MIC of Ng strains between categories using linear or hurdle regression for each antibiotic. RESULTS: We included 3367 gay and bisexual men who had sex with men (GBMSM), 516 women and 525 men who exclusively had sex with women (MSW) with Ng. Compared with GBMSM with a 'Dutch only' network, GBMSM with: (1) a Western European network had higher MICs for ceftriaxone (ß=0.19, 95% CI=0.08 to 0.29), cefotaxime (ß=0.19, 95% CI=0.08 to 0.31) and cefixime (ß=0.06, 95% CI=0.001 to 0.11); (2) a Southern European network had a higher MIC for cefixime (ß=0.10, 95% CI=0.02 to 0.17); and (3) a sub-Saharan African network had a lower MIC for ciprofloxacin (ß=-1.79, 95% CI=-2.84 to -0.74). In women and MSW, higher MICs were found for ceftriaxone in clients with a Latin American and Caribbean network (ß=0.26, 95% CI=0.02 to 0.51). CONCLUSIONS: For three cephalosporin antibiotics, we found Ng strains with slightly higher MICs in clients with partner(s) from Europe or Latin America and the Caribbean. International travel might contribute to the spread of Ng with lower susceptibility. More understanding of the emergence of AMR Ng is needed.

How to Defeat Multidrug-Resistant Bacteria in Intensive Care Units. A Lesson from the COVID-19 Pandemic. Prevention, Reservoirs, and Implications for Clinical Practice.

Background: Intensive care unit (ICU) patients are at high risk of infection due to multiple invasive procedures, malnutrition, or immunosuppression. The rapid increase in infections with multidrug-resistant organisms (MDRO) during the COVID-19 pandemic caused a dilemma, as the rules of the sanitary regime in ICU rooms were strictly adhered to in the prevailing epidemiological situation. The combat to reduce the number of infections and pathogen transmission became a priority for ICU staff. This study aimed to assess whether eliminating environmental reservoirs and implementing improved procedures for patient care and decontamination and washing equipment in the ICU reduced the incidence of infections caused by MDR strains. Material and methods: The study retrospectively analyzed data in the ICU during the COVID-19 pandemic. The samples were collected based on microbiological culture and medical records in the newly opened ICU (10 stations) and hospital wards where COVID-19 patients were hospitalized. Environmental inoculations were performed during the COVID-19 pandemic every 4-6 weeks unless an increase in the incidence of infections caused by MDR strains was observed. Through microbiological analysis, environmental reservoirs of MDR pathogens were identified. The observation time was divided into two periods, before and after the revised procedures. The relationship between isolated strains of Klebsiella pneumoniae NDM from patients and potential reservoirs within the ICU using ERIC-PCR and dice methods was analyzed. Results: An increased frequency of infections and colonization caused by MDRO was observed compared to the preceding years. A total of 23,167 microbiological tests and 6,985 screening tests for CPE and MRSA bacilli were collected. The pathogen spread was analyzed, and the findings indicated procedural errors. Assuming that the transmission of infections through the staff hands was significantly limited by the restrictive use of personal protective equipment, the search for a reservoir of microorganisms in the environment began. MDR strains were grown from the inoculations collected from the hand-wash basins in the wards and from inside the air conditioner on the ceiling outside the patient rooms. New types of decontamination mats were used in high-risk areas with a disinfectant based on Glucoprotamine. Active chlorine-containing substances were widely used to clean and disinfect surfaces. Conclusions: Infections with MDR strains pose a challenge for health care. Identification of bacterial reservoirs and comprehensive nursing care significantly reduce the number of nosocomial infections.

Antimicrobial susceptibility profile of Neisseria gonorrhoeae from patients attending a medical laboratory, Institut Pasteur de Madagascar between 2014 and 2020: phenotypical and genomic characterisation in a subset of Neisseria gonorrhoeae isolates.

OBJECTIVES: Antimicrobial-resistant Neisseria gonorrhoeae (NG) is a concern. Little is known about antimicrobial susceptibility profiles and associated genetic resistance mechanisms of NG in Madagascar. We report susceptibility data of NG isolates obtained by the medical laboratory (CBC) of the Institut Pasteur de Madagascar, Antananarivo, Madagascar, during 2014-2020. We present antimicrobial resistance mechanisms data and phenotype profiles of a subset of isolates. METHODS: We retrieved retrospective data (N=395) from patients with NG isolated during 2014-2020 by the CBC. We retested 46 viable isolates including 6 found ceftriaxone and 2 azithromycin resistant, as well as 33 isolated from 2020. We determined minimal inhibitory concentrations for ceftriaxone, ciprofloxacin, azithromycin, penicillin, tetracycline and spectinomycin using Etest. We obtained whole-genome sequences and identified the gene determinants associated with antimicrobial resistance and the sequence types (STs). RESULTS: Over the study period, ceftriaxone-resistant isolates exceeded the threshold of 5% in 2017 (7.4% (4 of 54)) and 2020 (7.1% (3 of 42)). All retested isolates were found susceptible to ceftriaxone, azithromycin and spectinomycin, and resistant to ciprofloxacin. The majority were resistant to penicillin (83% (38 of 46)) and tetracycline (87% (40 of 46)). We detected chromosomal mutations associated with antibiotic resistance in gyrA, parC, penA, ponA, porB and mtrR genes. None of the retested isolates carried the mosaic penA gene. The high rate of resistance to penicillin and tetracycline is explained by the presence of bla TEM (94.7% (36 of 38)) and tetM (97.5% (39 of 40)). We found a high number of circulating multilocus STs. Almost half of them were new types, and one new type was among the four most predominant. CONCLUSIONS: Our report provides a detailed dataset obtained through phenotypical and genotypical methods which will serve as a baseline for future surveillance of NG. We could not confirm the occurrence of ceftriaxone-resistant isolates. Our results highlight the importance of implementing quality-assured gonococcal antimicrobial resistance surveillance in Madagascar.

Developing a model of information transfer practice between institutions targeted at primary health care patients who are asymptomatic carriers of carbapenemase producing Enterobacteriacae.

BACKGROUND: Drug-resistant bacteria are one of the main reasons of deaths worldwide. A significant group of these bacteria are carbapenemase producing Enterobacteriaceae (CPE). The goal of this study was to develop a diagnostic and therapeutic model targeted at asymptomatic carriers of CPE. MATERIAL AND METHODS: A team of experts from different branches connected to health care, discussing the topic based on the data collected from previous research. Working sessions were dispersed between June and December 2022. The consensus has been reached via repeated discussion and literature search. RESULTS: The facility where CPE are detected is required to create an alert pathogen note and to notify sanitary-epidemiological station and National Reference Centre for Antimicrobial Susceptibility of Microorganisms - neither these institutions, nor the patient are required to notify the primary care physician. In primary care clinics, it is possible to work towards breaking the transmission of CPE by educating patients with CPE and persons who were in contact with them, and to undertake actions in order to look for patients with risk factors for CPE colonisation. In order to improve communication between individual levels of the health care system, standardised information could be introduced to the discharge note about a case of CPE, which will be electronically transmitted to the primary care facility. It might contribute to effective combating of the spread of CPE, by serving as a source of knowledge and education for patients and by checking the patient's risk factors, which will improve the performance of tests for CPE colonisation. CONCLUSIONS: The established model of good practice requires a change of legal regulations and its implementation, which will reduce the spread of CPE in health care facilities and will enable its future improvement. Med Pr Work Health Saf. 2023;74(4):263-70.

Increasing proportions of extended-spectrum ß-lactamase-producing isolates among Escherichia coli from urine and bloodstream infections: results from a nationwide surveillance network, Finland, 2008 to 2019.

BackgroundEscherichia coli is the leading cause of urinary tract infections (UTI) and bloodstream infections (BSI), and the emergence of antimicrobial resistance (AMR) in E. coli causes concern.AimTo investigate changes in the proportion of extended-spectrum ß-lactamase (ESBL) producing isolates among E. coli isolated from urine and blood in Finland during 2008-2019.MethodsSusceptibility testing of 1,568,488 urine (90% female, 10% male) and 47,927 blood E. coli isolates (61% female, 39% male) from all Finnish clinical microbiology laboratories during 2008-2019 was performed according to guidelines from the Clinical and Laboratory Standard Institute during 2008-2010 and the European Committee on Antimicrobial Susceptibility Testing during 2011-2019. A binomial regression model with log link compared observed trends over time and by age group and sex.ResultsThe annual proportion of ESBL-producing E. coli isolates among E. coli from blood cultures increased from 2.4% (23/966) to 8.6% (190/2,197) among males (average annual increase 7.7%; 95% CI: 4.4-11.0%, p < 0.01) and from 1.6% (28/1,806) to 6.4% (207/3,218) among females (9.3%; 95% CI: 4.8-14.0%, p < 0.01). In urine cultures, the proportion of ESBL-producing E. coli isolates increased from 2.2% (239/10,806) to 7.2% (1,098/15,297) among males (8.8%; 95% CI: 6.5-11.3%, p < 0.01) and from 1.0% (1,045/108,390) to 3.1% (3,717/120,671) among females (8.6%; 95% CI: 6.3-11.0%, p < 0.01). A significant increase was observed within most age groups.ConclusionsConsidering the ageing population and their risk of E. coli BSI and UTI, the increase in the annual proportions of ESBL-producing E. coli is concerning, and these increasing trends should be carefully monitored.

Changes in prevalence of Mycoplasma genitalium macrolide and fluoroquinolone resistance: notes from a 13-year retrospective survey in Dalarna County, Sweden.

OBJECTIVE: Macrolide and fluoroquinolone resistance in Mycoplasma genitalium (MG) is of emerging global concern. Compared with neighbouring countries such as Denmark, Sweden has had lower rates of macrolide resistance while fluoroquinolone resistance rates are less well documented. This study retrospectively examined macrolide, fluoroquinolone and multidrug resistance rates from Dalarna County, Sweden over a 13-year period. METHODS: MG-positive samples from 2006 to 2018 from patients examined at the Department of Venereology, Central Hospital, Falun, Sweden were tested by sequencing for macrolide resistance mutations (MRM) and fluoroquinolone resistance-associated mutations (QRAM) in the parC and gyrA subunit regions. A subset of these samples from 2006 to 2011 have been reported on previously, although only for MRM. RESULTS: Of 874 samples, 98 (11.2%, 95% CI 9.1% to 13.6%) had mutations associated with resistance to macrolides and 19 of 828 (2.3%, 95% CI 8.9% to 23.1%) to quinolones. Mutations associated with resistance to both drugs were detected in 5 of 828 (0.6%, 95% CI 0.1% to 1.4%) samples overall. A significant positive linear trend (p=0.004) for an increase in the rate of macrolide resistance was observed (from 0% in 2006 to 31% in 2018) while the increase in QRAM from 0% in 2006 to 12.3% in 2018 was not statistically significant. CONCLUSIONS: Despite a decrease in macrolide and fluoroquinolone consumption in Sweden, there was an overall increase in MG macrolide, fluoroquinolone and dual resistance from 2006 to 2018, although the difference in fluoroquinolone resistance rates was not statistically significant. In order to maintain comparably low resistance rates, resistance-guided therapy for MG infections will be crucial.

[Gram-negative bacteria of critical priority in ICU patients from a tertiary care hospital]. / Bacterias Gram-negativas de prioridad crítica en pacientes de las UCI de un hospital de tercer nivel.

Background: Intensive care units (ICU) are the epicenter of antimicrobial resistance (AMR), and patients' infections are mainly caused by Gram-negative bacteria (GNB). Objective: To describe the frequency and trends in AMR of GNB deriving from the clinical samples of ICU patients at a tertiary care hospital in Mérida, Yucatán. Material and methods: Study which included the review of laboratory reports of all bacteriological samples collected from patients admitted to neonatal, pediatric and adult ICU from January 1 2019 to December 31 2021. Results: 433 GNB isolates were recovered, with Klebsiella pneumoniae being the most predominant isolate (n = 117; 27.02%). The majority of GNB were recovered from bronchial secretions (n = 163). Overall, GNB showed high resistance rates to ampicillin (89.48%), ampicillin/sulbactam (66.85%), cephalosporins (58.52-93.81%), tobramycin (58.06%), and tetracycline (61.73%). Among GNB, 73.90% and 68.53% exhibited multidrug-resistant, and highly resistant microorganisms' profiles, respectively, and 47.54% of Acinetobacter baumannii exhibited an extensively drug-resistant profile. A total of 80.33% of A. baumannii was carbapenem-resistant, and 83.76% of K. pneumoniae strains were ESBL-producing. Conclusion: Our data could be helpful to improve the empirical therapy and the infection-control program.

Introducción: las unidades de cuidados intensivos (UCI) son el epicentro de la resistencia a los antimicrobianos (RAM) y las infecciones en estas áreas son causadas principalmente por bacterias Gram-negativas (BGN). Objetivo: describir la frecuencia y los patrones de RAM en BGN aisladas de muestras clínicas de pacientes de las UCI de un hospital de tercer nivel en Mérida, Yucatán. Material y métodos: estudio que incluyó la revisión de los reportes de laboratorio de las muestras bacteriológicas obtenidas de pacientes ingresados en las UCI neonatal, pediátrica y adulta del 1 de enero de 2019 al 31 de diciembre de 2021. Resultados: se identificaron 433 BGN y Klebsiella pneumoniae fue el patógeno más prevalente (n = 117; 27.02%). La mayoría de las BGN aisladas se obtuvieron de secreciones bronquiales (n = 163). En general, las BGN mostraron altas tasas de resistencia a ampicilina (89.48%), ampicilina/sulbactam (66.85%), cefalosporinas (58.52-93.81%), tobramicina (58.06%) y tetraciclina (61.73%). El 73.90% y el 68.53% de las BGN exhibieron perfiles multidrogorresistentes y microorganismos altamente resistentes a fármacos, respectivamente, y 47.54% de los aislamientos de Acinetobacter baumannii mostró perfil de drogorresistencia extendida. El 80.33% de los A. baumannii fue resistente a carbapenémicos y el 83.76% de las K. pneumoniae fueron productoras de BLEE. Conclusión: nuestros datos podrían mejorar la terapia antimicrobiana empírica y el programa de control de infecciones.

Caracterización de ß-lactamasas de espectro extendido en aislamientos clínicos colombianos de Salmonella enterica no tifoidea de 1997 a 2022 / Characterization of extended spectrum ß-lactamases in Colombian clinical isolates of non-typhoidal Salmonella enterica between 1997 and 2022

Introducción. Salmonella spp. es un agente patógeno zoonótico transmitido al humano por el agua o los alimentos contaminados. La presencia de ß-lactamasas de espectro extendido es un creciente problema para la salud pública debido a que estas enzimas confieren resistencia contra las cefalosporinas de tercera y cuarta generación. Objetivo. Caracterizar las ß-lactamasas de espectro extendido en aislamientos de Salmonella spp. recibidos por el programa de vigilancia de enfermedad diarreica aguda o enfermedad transmitida por alimentos del Grupo de Microbiología del Instituto Nacional de Salud. Materiales y métodos. Entre enero de 1997 y junio de 2022, se recibieron 444 aislamientos de Salmonella spp. resistentes, por lo menos, a una de las cefalosporinas de tercera generación. El fenotipo de las ß-lactamasas de espectro extendido se identificó con la prueba de doble disco. El ADN se extrajo por ebullición y mediante PCR se amplificaron los genes bla CTX-M, bla SHVy : ' a ILM. Resultados. Todos los aislamientos fueron positivos para la prueba de ß-lactamasas de espectro extendido. Los resultados de la amplificación por PCR fueron: bla CTX-M + bla TLM (n=200), bla CTX-M (n=177), bla SHV(n=16), bla SHV + bla CTX-M (n=6), bla TLM (n=13) y bla SHV + bla CTX-M + bla TLM (n=3). Del total, 26 aislamientos fueron negativos para los genes evaluados. Los aislamientos positivos para ß-lactamasas de espectro extendido se identificaron en Bogotá y en 21 departamentos: Chocó, Magdalena, Meta, Bolívar, Casanare, Cesar, Córdoba, Quindío, Atlántico, Tolima, Cauca, Cundinamarca, Huila, Boyacá, Caldas, Norte de Santander, Risaralda, Antioquia, Nariño, Santander y Valle del Cauca. Conclusión. La resistencia a las cefalosporinas de tercera generación en aislamientos de Salmonella spp. fue generada principalmente por bla CTX-M. El 44 % (197/444) de los aislamientos presentó resistencia a ampicilina, tetraciclina, cloranfenicol y trimetoprim- sulfametoxazol Los serotipos portadores de ß-lactamasas de espectro extendido más frecuentes fueron S. Typhimurium y S. Infantis.

Introduction. Salmonella spp. is a zoonotic pathogen transmitted to humans through contaminated water or food. The presence of extended-spectrum ß-lactamases is a growing public health problem because these enzymes are resistant to third and fourth generation cephalosporins. Objective. To characterize extended-spectrum ß-lactamases in Salmonella spp. isolates received by the acute diarrheal disease/foodborne disease surveillance program of the Grupo de Microbiología of the Instituto Nacional de Salud. Materials and methods. A total of 444 Salmonella spp. isolates, resistant to at least one of the cephalosporins, were obtained between January 1997 and June 2022. The extended- spectrum ß-lactamases phenotype was identified by the double disk test. DNA extraction was carried out by the boiling method, and the bla CTX-M, bla SHV, and bla TLM genes were amplified by PCR. Results. All the isolates were positive for the extended-spectrum ß-lactamases test. The genes identified were: bla CTX-M + ba TLM (n=200), bla CTX-M (n=177), bla SHV(n=16), bla SHV + bla CTX-M (n=6), bla TLM (n=13) and bla SHV + bla CTX-M + bla TLM (n=3). Twenty-six isolates were negative for the evaluated genes. Positive extended-spectrum ß-lactamases isolates were identified in Bogotá and 21 departments: Chocó, Magdalena, Meta, Bolívar, Casanare, Cesar, Córdoba, Quindío, Atlántico, Tolima, Cauca, Cundinamarca, Huila, Boyacá, Caldas, Norte de Santander, Risaralda, Antioquia, Nariño, Santander y Valle del Cauca. Conclusion. Resistance to third generation cephalosporins in Salmonella spp. isolates was mainly caused by bla CTX-M. Isolates were resistant to ampicillin, tetracycline, chloramphenicol, and trimethoprim-sulfamethoxazole (44 %; 197/444). The most frequent extended-spectrum ß-lactamases-expressing serotypes were Salmonella Typhimurium and Salmonella Infantis.

Rats as sources of multidrug-resistant Enterobacteriaceae in animal production environments.

Rattus norvegicus and Rattus rattus are commensal pest rodents, considered reservoirs and vectors of zoonotic pathogens. In livestock farms, the wide use of antimicrobials and their release into the environment lead to high long-term residual concentrations, which may in turn lead to the occurrence of antimicrobial resistance (AMR). Farm environments serve as AMR sources, resulting in the transmission of antimicrobial-resistant bacteria and their AMR genes of livestock origin into wildlife. This study aimed to analyse the profile of enterobacteria carrying AMR determinants in rats captured in livestock farms to determine their potential vectors as for the spread of AMR. To this end, 56 rats (52 R. norvegicus and 4 R. rattus) were live-trapped on 11 farms (pig, dairy, poultry and mixed farms) located in central Argentina, from spring 2016 to autumn 2017. From 50 of the R. norvegicus individuals and three of the R. rattus individuals found in 10 of the farms, we isolated 53 Escherichia coli and five Salmonella strains. Susceptibility to antimicrobials, genotypic profiles, minimal inhibitory concentration of colistin and the presence of mcr-1 and genes encoding extended-spectrum ß-lactamase (ESBL) were determined. Of the 58 isolates not susceptible to different antimicrobial classes, 28 of the E. coli strains and two of the Salmonella strains were defined as multi-drug resistant (MDR). S. Westhampton and S. Newport recovered were not susceptible to ampicillin or all the cephems tested. One of the E. coli obtained showed resistance to colistin and harboured the mcr-1 gene, demonstrated by PCR and conjugation. In two ESBL-producing Salmonella isolated from rats, CTX-M-2 genes were responsible for the observed resistance to third-generation cephalosporins. The MDR E. coli isolates showed several different resistance patterns (23), although some of them were the same in different individuals and different farms, with six resistance patterns, evidencing the dispersion of strains. These findings suggest that rats play a role in the dissemination of AMR determinants between animal, humans and environmental reservoirs.

[Urinary tract infections including pyelonephritis]. / Harnwegsinfektionen einschließlich Pyelonephritis.

Urinary tract infections (UTIs) are among the most common bacterial infections. The clinical phenotypes of UTIs are heterogeneous, ranging from rather benign uncomplicated infections to complicated UTIs and pyelonephritis to severe urosepsis. There has been a sharp increase in the incidence of severe UTIs, whilst the incidence of sepsis in general is declining. The classifications of UTIs partially differ between clinical and regulatory claims. Experience has also been gained over the last few years to define the appropriate endpoints that are used in clinical studies. Above all, patient-centered evaluation strategies of the endpoints were developed, in order to be able to identify the advantages of new antibiotics compared to traditional antibiotics. The development of new antibiotics for UTIs is essential, since multidrug-resistant enterobacteria, which belong to the typical bacterial spectrum of UTIs, are frequently associated with mortality from infections. In recent years, several new antibiotics/combinations that are particularly effective against multi-resistant gram-negative pathogens have been investigated for the treatment of UTIs.

Otitis externa maligna con diseminación hematógena de Pseudomonas aeruginosa resistente a carbapenémicos

Pseudomonas aeruginosa en una bacteria Gram negativa no fermentadora que produce diversos tipos de infecciones severas en inmunocompetentes e inmunodeprimidos. Una de estas infecciones es la otitis externa maligna, la cual se presenta principalmente en personas con diabetes mellitus y puede tener una evolución tórpida cursando con osteomielitis de base de cráneo y parálisis de nervios craneales. El tratamiento es individualizado y principalmente conservador con antibioticoterapia guiada por cultivo. La bacteria aislada en la mayoría de los casos reportados es sensible a los antibióticos anti-pseudomónicos. Reportamos un caso de presentación inusual de otitis externa maligna por Pseudomonas aeruginosa resistente a carbapenémicos con evidencia sugerente de compromiso bilateral y en el cual se aisló al mismo germen en urocultivo y hemocultivos, lo que indicaría una diseminación hematógena del microorganismo.

Pseudomonas aeruginosa is a non-fermenting Gram-negative bacterium that produces several types of severe infections in immunocompetent and immunosuppressed patients. One of these infections is malignant otitis externa, which occurs mainly in people with diabetes mellitus and can have a torpid evolution coursing with osteomyelitis of skull base and cranial nerve palsies. Treatment is individualized and mainly conservative with culture-guided antibiotic therapy, with isolated pseudomonas being sensitive to anti-pseudomonal antibiotics in the majority of reported cases. We report a case of unusual presentation of malignant otitis externa caused by Pseudomonas aeruginosa resistant to carbapenems with suggestive evidence of bilateral involvement and in which the same germ was isolated in urine and blood cultures, which would indicate hematogenous dissemination of the microorganism.

Resistencia antimicrobiana, una pandemia silenciosa / Antimicrobial resistance, a silent pandemic / Resistência antimicrobiana, uma pandemia silenciosa

Introducción: la resistencia a los antimicrobianos ha sido una problemática creciente a nivel global, la problemática afecta no solo la salud de personas, animales y el ambiente en general, sino que ha generado impactos de índole productivo y comercial. Una de las estrategias para abordar esta problemática es el enfoque de una salud. Este enfoque destaca la participación multidisciplinaria para combatir la resistencia antimicrobiana; y es así que cada profesión o actividad laboral genera unas responsabilidades innatas para la profesión veterinaria. Los veterinarios tienen un rol fundamental para este propósito, ya que son ellos quienes integran la aplicabilidad de estrategias de promoción y prevención a nivel agropecuario, y de consolidación e interlocución entre los diferentes componentes del enfoque (animal, humano, ambiente) desde el ámbito de la salud pública veterinaria. Materiales y Método: se realizó una búsqueda de la literatura en diferentes bases de datos, con el objetivo de realizar una revisión actualizada sobre la resistencia antimicrobiana. Resultados: dentro de las principales estrategias se debería fomentar un uso adecuado y bajo prescripción de antimicrobianos en la producción animal. Promover buenas prácticas de higiene, bioseguridad y vacunación, facilitando un correcto diagnóstico de enfermedades infecciosas en animales. Discusión: la adopción de normas internacionales para el uso responsable de los antibióticos y las directrices establecidas por la Organización Mundial de la Salud y Organización de las Naciones Unidas para la Alimentación y la Agricultura, a través del Codex Alimentarius y la Organización Mundial de Sanidad Animal, son fundamentales para hacer frente al desafío que representa el problema de la resistencia a los antimicrobianos.

Introduction: Antimicrobial resistance has been a growing problem at a global level, affecting not only the health of people, animals and the environment in general, but it has also generated impacts of a productive and commercial nature. One of the strategies to address this problem is the one-health approach. This approach emphasizes multidisciplinary participation to combat antimicrobial resistance; and thus, each profession or work activity generates innate responsibilities for the veterinary profession. Veterinarians have a fundamental role for this purpose, since they are the ones who integrate the applicability of promotion and prevention strategies at the agricultural level, and of consolidation and interlocution between the different components of the approach (animal, human, environment) from the field of veterinary public health. Materials and Method: a literature search was carried out in different databases, with the aim of carrying out an updated review on antimicrobial resistance. Results: one of the main strategies should be to promote an adequate use and under prescription of antimicrobials in animal production. Promote good hygiene, biosecurity and vaccination practices, facilitating a correct diagnosis of infectious diseases in animals. Discussion: the adoption of international standards for the responsible use of antibiotics and the guidelines established by the World Health Organization and the Food and Agriculture Organization of the United Nations, through Codex Alimentarius and the World Organization for Animal Health, are fundamental to face the challenge posed by the problem of antimicrobial resistance.

Introdução: A resistência antimicrobiana tem sido um problema crescente em todo o mundo, afetando não apenas a saúde dos seres humanos, dos animais e do meio ambiente em geral, mas também causando impactos na produção e no comércio. Uma das estratégias para lidar com esse problema é a abordagem One Health. Essa abordagem enfatiza o envolvimento multidisciplinar no combate à resistência antimicrobiana, com cada profissão ou atividade de trabalho gerando responsabilidades inatas à profissão veterinária. Os veterinários têm um papel fundamental nesse sentido, pois são eles que integram a aplicabilidade das estratégias de promoção e prevenção em nível agropecuário e de consolidação e interlocução entre os diferentes componentes da abordagem (animal, humano, ambiental) do campo da saúde pública veterinária. Materiais e Métodos: foi realizada uma pesquisa bibliográfica em diferentes bases de dados, com o objetivo de realizar uma revisão atualizada sobre a resistência antimicrobiana. Resultados: uma das principais estratégias deve ser a promoção do uso adequado e com baixa prescrição de antimicrobianos na produção animal. Promover boas práticas de higiene, biossegurança e vacinação, facilitando o diagnóstico correto de doenças infecciosas em animais. Discussão: A adoção de padrões internacionais para o uso responsável de antibióticos e as diretrizes estabelecidas pela Organização Mundial da Saúde e pela Organização das Nações Unidas para Agricultura e Alimentação, por meio do Codex Alimentarius e da Organização Mundial de Saúde Animal, são essenciais para enfrentar o desafio representado pelo problema da resistência antimicrobiana.

Epidemiology of antimicrobial resistance in bacteria isolated from inpatient and outpatient samples, Ecuador, 2018.

Objective: To compare the epidemiology of antimicrobial resistance in bacteria isolated from inpatient and outpatient samples in Ecuador. Methods: A secondary analysis was done of data on bacteria isolated from inpatient and outpatient samples. Data were taken from the 2018 national antimicrobial resistance surveillance database of the National Reference Center for Antimicrobial Resistance. The variables included were: age, sex, inpatient versus outpatient setting, type of specimen, bacterial species identified, pattern of resistance to antibiotics, and geographic area. Results: Data from 57 305 bacterial isolates were included in the study: 48.8% were from hospitalized patients, 55.7% were from women, and 60.1% were from patients older than 45 years. Urine (42.9%) and blood (12.4%) were the most common clinical samples. Overall, 77.1% of bacterial isolates were gram-negative (83% and 71% in outpatients and inpatients, respectively). The most common gram-positive and gram-negative species were Staphylococcus aureus and Escherichia coli, respectively. Antimicrobial resistance levels were high (up to 80% for some antimicrobial drugs), and were higher in hospitalized patients compared with outpatients. A variety of carbapenemases were found to confer resistance to carbapenems (antibiotics of last resort) in gram-negative bacteria. Conclusions: The study findings provide an important baseline on antimicrobial resistance in Ecuador. This will allow the strengthening of guidelines of the surveillance system, the creation of public policies for standardization of laboratory methodologies, the proper handling of information, and the development of empirical therapy guidelines based on local epidemiology.

Challenges of Multidrug-resistant New Delhi Metallo-beta-Lactamase (NDM-1)-producing Enterobacteriaceae in Kidney Transplant Patients / Desafios da Enterobacteriaceae produtora de New Delhi Metalo-beta-Lactamase (NDM-1) multirresistente em pacientes com transplante renal

Abstract Background: The emergence of multidrug-resistant NDM-1-producing enterobacteriaceae strains has become a threat to inpatients, especially to immunosuppressed ones, such as kidney transplant recipients. NDM-1 is a carbapenemase that makes gram-negative bacteria resistant to many types of antibiotics. The incidence of carbapenemase-producing enterobacteria infection in solid organ transplant recipients is around 3 to 10%, with a mortality rate of up to 30%. Methods: We present a case series of 4 patients with NDM-1-producing enterobacteria isolated in urine cultures or rectal swabs. We also conducted a cross-sectional study 30 days after patient identification, collecting surveillance cultures (rectal swab) from all inpatients to assess the extent of spread of this resistance mechanism; a total of 101 patients were included. Results: Two patients were adequately treated with negative control cultures. The other two patients were not treated because they were asymptomatic and had subsequent negative urine cultures. No new colonization was identified in the cross-sectional screening, and no new cases of urinary NDM-1 infection were recorded after a 4-year follow-up. Conclusion: Surveillance for infections caused by multidrug-resistant strains in hospitals treating immunosuppressed patients should be continued and prompt action should be taken in cases of outbreaks of multidrug-resistant infections.

Resumo Histórico: O surgimento de cepas multirresistentes de enterobacteriaceae produtoras de NDM-1 tornou-se uma ameaça para pacientes hospitalizados, especialmente para os imunossuprimidos, como os receptores de transplante renal. NDM-1 é uma carbapenemase que torna as bactérias gram-negativas resistentes a muitos tipos de antibióticos. A incidência de infecção por enterobactérias produtoras de carbapenemas em receptores de transplante de órgãos sólidos é de cerca de 3 a 10%, com uma taxa de mortalidade de até 30%. Métodos: Apresentamos uma série de casos de 4 pacientes com enterobactérias produtoras de NDM-1 isoladas em culturas de urina ou esfregaços retais. Também realizamos um estudo transversal 30 dias após a identificação do paciente, coletando culturas de vigilância (esfregaço retal) de todos os pacientes internados para avaliar a extensão de disseminação deste mecanismo de resistência; foram incluídos um total de 101 pacientes. Resultados: Dois pacientes foram tratados adequadamente com culturas de controle negativo. Os outros dois pacientes não foram tratados porque eram assintomáticos e tiveram culturas de urina negativas subsequentes. Não foi identificada nenhuma nova colonização na triagem transversal, e não foram registrados novos casos de infecção urinária por NDM-1 após um acompanhamento de 4 anos. Conclusão: A vigilância de infecções causadas por cepas multirresistentes em hospitais que tratam pacientes imunossuprimidos deve ser continuada e devem ser tomadas medidas imediatas em casos de surtos desses tipos de infecções.

[Bacterial resistance, a current crisis.] / Resistencia bacteriana, una crisis actual.

Bacterial resistance is a constant battle representing a Public Health trouble. So much, that the World Health Organization considerate Public Health as a priority in health, due to the impact that generates as much as in health (giving that recent projections indicate that by 2050 it'll be produced more deaths because of this than the ones occasioned because of cancer) as its economic impact (which, according to a recent study in the United Kingdom, it'll cost the world's economy an estimated of 100 trillion dollars). The quick appearance of multidrug-resistant and pandrug-resistant bacteria is a world nature phenomenon, questioning the antibiotics efficiency. Implement protocols and recommendations is essential, just as essential and necessary as give awareness to health personnel, taking as base the knowledge of resistance generation and its impact through the years, empowered by the actual pandemic of COVID 19.

La resistencia bacteriana es una constante batalla que representa un problema de Salud Pública. Tan es así que la Organización Mundial de la Salud (OMS) la considera de sus prioridades en salud, debido al impacto que genera tanto en la salud (dado que proyecciones recientes indican que para 2050 se producirán más muertes por esta causa que las ocasionadas actualmente por el cáncer), como a su impacto económico (que, de acuerdo a un estudio reciente en el Reino Unido, costará a la economía mundial un estimado de 100 billones de dólares anualmente). La veloz aparición de bacterias multirresistentes y panresistentes es un fenómeno de índole mundial, cuestionando la eficacia antibiótica. Implementar protocolos y recomendaciones es vital, de igual forma que es necesario conciencias al personal sanitario, tomando como base el conocimiento de generación de resistencia y su impacto a través de los años, potenciado por la actual pandemia de la COVID-19.