The most common mistakes in intensive care - antibiotics.

The enormous increase in antibiotic resistance and the limited spectrum of new, effective antibiotics are the reasons why we should think about a rational approach to anti-infective therapy. The excessive and non-indicated use of antibiotics while treating critically ill patients can be found quite often in clinical practice. Antibiotic therapy is usually indicated empirically, or it is only based on therapeutic indecision, not just in ICU patients. The antibiotics are administered before taking a sample for microbiological analysis or there is no therapy adjustment based on the laboratory findings. The solution lies in antibiotic stewardship, which is the way to ensure that antibiotics will be sufficiently effective in years to come.

Antimicrobial resistance profiles of Listeria species recovered from retail outlets in Gauteng Province, South Africa.

The study determined the antimicrobial resistance (AMR) profiles of Listeria spp. (L. monocytogenes, L. innocua and L. welshimeri) recovered from beef and beef products sold at retail outlets in Gauteng Province, South Africa. A total of 112 isolates of Listeria spp., including L. monocytogenes (37), L. innocua (65), and L. welshimeri (10), were recovered from beef and beef products collected from 48 retail outlets. Listeria spp. was recovered by direct selective plating following selective enrichment, and PCR was used to confirm and characterize recovered isolates. The disc diffusion method determined the resistance to 16 antimicrobial agents. All 112 isolates of Listeria spp. exhibited resistance to one or more antibiotics (P<0.05). The prevalence of AMR in Listeria isolates was high for nalidixic acid (99.1%) and cefotaxime (80.4%) but low for gentamycin (2.7%), sulfamethoxazole-trimethoprim (3.6%), azithromycin (5.4%), and doxycycline (6.3%). Overall, for the three species of Listeria, the prevalence of resistance varied significantly only for streptomycin (P=0.016) and tetracycline (P=0.034). Multidrug-resistant isolates were detected in 75.7% (28/37), 61.5% (40/65), and 80% (8/10) isolates of L. monocytogenes, L. innocua, and L. welshimeri, respectively. The prevalence of AMR was significantly affected by the location and size of retail outlets, type of beef and beef products, and serogroups of L. monocytogenes. The high prevalence of AMR, particularly among the L. monocytogenes isolates, poses potential therapeutic implications for human consumers of contaminated beef products. There is, therefore, a need to regulate and enforce the use of antimicrobial agents in humans and animals in South Africa.

Awareness Regarding Antimicrobial Resistance and Antibiotic Prescribing Behavior among Physicians: Results from a Nationwide Cross-Sectional Survey in India.

(1) Background: Understanding the physicians' knowledge, attitudes, and antimicrobial prescribing behavior is a crucial step towards designing strategies for the optimal use of these agents. (2) Methods: A cross-sectional online survey was conducted among clinicians across India between May and July 2022 using a self-administered questionnaire in English comprising 35 questions pertaining to demographic characteristics, knowledge, attitude, and practices domains. (3) Results: A total of 544 responses were received from 710 physicians contacted. Sixty percent of participants were males, with mean age of 34.7 years. Mean ± Standard Deviation scores for knowledge, attitude, and practices domains were 8 ± 1.6, 20.2 ± 3.5, and 15.3 ± 2.1, respectively. Higher scores were associated with basic [odds ratio (95% Confidence Interval), p value: 2.95 (1.21, 7.2), 0.02], medical and allied sciences [2.71 (1.09, 6.67), 0.03], and central zone [3.75 (1.39, 10.12), 0.009]. A substantial proportion of dissatisfactory responses were found regarding hospital antibiograms, antibiotics effective against anaerobes, WHO AWaRe (access, watch, and reserve) classification of antibiotics, and the role of infection prevention and control (IPC) measures in the containment of antimicrobial resistance (AMR). (4) Conclusions: There is a need to sensitize and educate clinicians on various issues related to antimicrobial use, such as antibiograms, double anaerobic cover, IPC practices, and guideline-based recommendations, to curb the AMR pandemic.

Escherichia coli O157:H7 beef carcass contamination and its antibiotic resistance in Awi Zone, Northwest Ethiopia.

Escherichia coli O157:H7 is a cause of foodborne disease and global public health issues especially in developing countries like Ethiopia. A cross-sectional study was done from January 2022 to July 2022 in Awi Zone to assess the occurrence and antibiograms of E. coli O157:H7. Abattoirs and butcher shops were selected purposively, whereas a systematic random and purposive sampling technique was employed to select study units in abattoirs and butcher shops, respectively. A total of 248 swab samples were collected, isolated, and confirmed using bacteriological culture, biochemical tests, and latex agglutination tests. Escherichia coli O1157:H7 antibiogram tests were performed using Kirby-Bauer disk diffusion method. Logistic regression was used to analyze and measure the degree of association between the presumed risk factors and E. coli O157:H7 occurrence. The overall occurrence of E. coli O157:H7 was estimated to be 8.87% and a relative higher (11.29%) occurrence of E. coli O157:H7 was recorded at butcher shops when compared to abattoirs (6.45%). All isolates were susceptible to gentamicin followed by chloramphenicol (81.81%). About 81.81% of the isolates were resistant to ampicillin and 77.23% of isolates developed resistance to two and more than two antibiotics (MDR). In conclusion, E. coli O157:H7 was detected in the study area. Thus, educating abattoir and butcher shop workers, and consumers, on hygienic handling practices and safe consumption of meat could eliminate foodborne infection associated with E. coli O157:H7 occurrence.

Approaches Used to Construct Antibiograms for Dogs in a Veterinary Teaching Hospital in the United States.

Non-judicious antimicrobial use (AMU) is a major driver of antimicrobial resistance (AMR). In human hospitals, cumulative antibiograms are often used by clinicians to evaluate local susceptibility rates and to select the most appropriate empiric therapy with the aim of minimizing inappropriate AMU. However, the use of cumulative antibiograms to guide empiric antimicrobial therapy in veterinary hospitals in the United States is limited, and there are no specific guidelines or standardized methods available for the construction of antibiograms in veterinary clinical settings. The objective of this methods article is to describe the approaches that were used to construct antibiograms from clinical samples collected from dogs seen at a veterinary teaching hospital. Laboratory data for 563 dogs for the period from 1 January 2015 to 31 December 2015 was utilized. We used the Clinical and Laboratory Standards Institute (CLSI) guidelines for use in the construction of the antibiograms in human healthcare settings as the basis for the veterinary antibiograms. One general antibiogram and antibiograms stratified by hospital section, the anatomic region of sample collection/by sample type, were created and the challenges encountered in preparing these antibiograms were highlighted. The approaches described could be useful in guiding veterinary antibiogram development for empiric therapy.

Sperm culture and bacterial susceptibility to antibiotics in a large andrological population: prevalence and impact on seminal parameters / Cultivo de semen y susceptibilidad bacteriana a los antibióticos en una gran población andrológica: prevalencia e impacto en los parámetros seminales

Background: The aim of this study was to evaluate (i) the prevalence of subjects with a positive sperm culture (SC) for bacteria in subjects with or without genitourinary tract inflammation (GTI); (ii) the actual distribution of the species analysed, according to Gram stain; (iii) the impact on sperm parameters; and (iv) the actual bacterial susceptibility to antibiotics. Methods: A total of 930 subjects (18–55) years, were retrospectively studied. All the patients underwent SC and in the case of positive tests (CFU > 106), a microbiological susceptibility analysis. The subjects studied were subdivided into group A (n = 452), with subjective signs of GTI; group B (n = 478), male partners of infertile couples; and group C, 30 healthy normospermic subjects. In group B and in the control group, a semen analysis was performed. Results: Overall, the prevalence of positive SC was 21.5% (200/930). The prevalence of positive SC in group A (113/200; 56.5%) was significantly higher vs. group B (87/200; 43.5%; p = 0.01) and control group (1/30; 3.3%; p = 0.0001). In subjects with GTI, the prevalence of asthenozoospermic (96/285; 33.7%) and oligo-asthenozoospermic (98/285; 34.4%) was significantly higher vs. normospermic, oligo-astheno-teratozoospermic, oligozoospermic and azoospermic subjects (22/285 (7.7%), 48/285 (16.8%), 15/285 (5.3%) and 6/285 (2.1%), respectively; p = 0.001). Finally, Enterococcus faecalis (Gram-positive) and Escherichia coli (Gram-negative) showed the highest prevalence of antibiotic resistance. Conclusions: The prevalence of positive SC is higher in GTI subjects; however, the SC could also be positive in subjects without GTI. Commonly used antibiotics have an increasing risk of being useless for the treatment of bacterial infections. Finally, the diagnosis of GTIs is important also for male fertility.(AU)

Sperm culture and bacterial susceptibility to antibiotics in a large andrological population: prevalence and impact on seminal parameters.

BACKGROUND: The aim of this study was to evaluate (i) the prevalence of subjects with a positive sperm culture (SC) for bacteria in subjects with or without genitourinary tract inflammation (GTI); (ii) the actual distribution of the species analysed, according to Gram stain; (iii) the impact on sperm parameters; and (iv) the actual bacterial susceptibility to antibiotics. METHODS: A total of 930 subjects (18-55) years, were retrospectively studied. All the patients underwent SC and in the case of positive tests (CFU > 106), a microbiological susceptibility analysis. The subjects studied were subdivided into group A (n = 452), with subjective signs of GTI; group B (n = 478), male partners of infertile couples; and group C, 30 healthy normospermic subjects. In group B and in the control group, a semen analysis was performed. RESULTS: Overall, the prevalence of positive SC was 21.5% (200/930). The prevalence of positive SC in group A (113/200; 56.5%) was significantly higher vs. group B (87/200; 43.5%; p = 0.01) and control group (1/30; 3.3%; p = 0.0001). In subjects with GTI, the prevalence of asthenozoospermic (96/285; 33.7%) and oligo-asthenozoospermic (98/285; 34.4%) was significantly higher vs. normospermic, oligo-astheno-teratozoospermic, oligozoospermic and azoospermic subjects (22/285 (7.7%), 48/285 (16.8%), 15/285 (5.3%) and 6/285 (2.1%), respectively; p = 0.001). Finally, Enterococcus faecalis (Gram-positive) and Escherichia coli (Gram-negative) showed the highest prevalence of antibiotic resistance. CONCLUSIONS: The prevalence of positive SC is higher in GTI subjects; however, the SC could also be positive in subjects without GTI. Commonly used antibiotics have an increasing risk of being useless for the treatment of bacterial infections. Finally, the diagnosis of GTIs is important also for male fertility.

Endophthalmitis panorama in the Jerusalem area.

PURPOSE: The spectrum of microbial infections and the pattern of their susceptibility are variable among communities. Researching these data will lead to the establishment of the most appropriate national management strategies. The purpose of this study was to analyze the epidemiological, clinical, microbial spectrum and antibiotic susceptibility of endophthalmitis cases in a tertiary referral center in Jerusalem. METHODS: Retrospective review of medical charts of patients presenting with endophthalmitis over a 12-year period. RESULTS: A total of 74 eyes of 70 patients (males 56%) were included. Mean age ± SD at presentation was 60 ± 19.5 years. Exogenous endophthalmitis accounted for 78% of cases, of which 62% followed an intraocular surgery, 21% occurred after intravitreal injections, 10% followed infectious keratitis and 7% were posttraumatic. Endogenous cases were predominantly observed in diabetic patients. Microbial isolates were identified in 44 samples. Of them, gram-positive bacteria were the predominant microorganisms detected in 33 samples (75%); Staphylococcus epidermidis and Enterococcus faecalis were the most commonly detected pathogens. Mean presenting ± SD LogMAR visual acuity (VA) was 2.38 ± 1.21 and it improved at last follow-up to 1.7 ± 1.37 (p = 0.004, paired t test). Cases secondary to gram-positive microbes were associated with improved VA during the follow-up while cases secondary to gram-negative microbes was correlated with poor final VA (p = 0.046, r2 = 0.4). There was no evidence of bacterial resistance in the antibiograms for either vancomycin, ceftazidime, ceftriaxone or amikacin. CONCLUSIONS: Intraocular surgery remains the most common event preceding endophthalmitis with coagulase-negative staphylococci being the most frequently detected microorganisms. The microbial spectrum of endophthalmitis is similar to that in the western world.

Bacteriological profile of wound infections and antimicrobial resistance in selected gram-negative bacteria.

Background: Managing wound infections is a challenging task. Understanding their resistance pattern is an essential step at reducing its burden in hospital settings. Objective: To determine the bacteriological diversity of wound infections and the antimicrobial resistance exhibited by a selected Gram-negative bacterium in the Aljouf region of Saudi Arabia. Methods: The study retrospectively analysed the antibiograms of wound infections from hospitalized patients for the year 2019. The European Centre for Disease Control guidelines were adopted for the classification of resistant bacteria. Multidrug-, extensive drug-, and carbapenem-resistant isolates are presented as frequencies and percentages. Results: A total of 295 non-duplicate wound swab antibiograms were retrieved, 64.4% (190) and 35.6% (105) isolates were Gram-negative and Gram-positive bacterial infections respectively. Predominant pathogens included Staphylococcus species 21.0% (62), E. coli 16.3% (48) and K. pneumoniae 13.5% (40). 148 (77.9%), 42 (22.1%) and 43 (22.6%) of the Gram-negative isolates were multidrug-, extensively drug- and carbapenem-resistant. The antibiotic resistance exhibited by gram-negative bacteria was 43.4% (234/539), 59.1% (224/379) and 53.7% (101/188) towards carbapenems, 3rd - and 4th - generation cephalosporins. Conclusions: The majority of wound infections are caused by multidrug-, extensively drug- and carbapenem-resistant Gram-negative bacteria. Further studies should focus on the molecular basis of this resistance.

Determination of frequency, multiple antibiotic resistance index and resistotype of Salmonella spp. in chicken meat collected from southeast of Iran.

BACKGROUND: Zoonotic food-borne pathogens such as Salmonella spp., which can be hosted by some raw foods, play a crucial role in ranking the public health of a country OBJECTIVES: The present study was conducted to assess the frequency, antibiotic resistance pattern and index of multiple antibiotic resistance (MAR) of Salmonella spp. in chicken meat METHODS: A cross-sectional survey was conducted from October 2017 to March 2018. One-hundred and fifty chicken meat samples were collected from meat stores in Zahedan, southeast of Iran and screened for contamination with Salmonella spp. using the polymerase chain reaction assay targeting the inv-A gene. Antimicrobial susceptibility testing was performed against 11 commonly prescribed antimicrobial agents in the veterinary treatment to calculate the MAR index RESULTS: The contamination rate was 2.7% (4/150). The antimicrobial resistance rate was 100% (n = 4) against penicillin, tylosin, tetracycline, erythromycin and tiamulin, 50% (n = 2) against trimethoprim/sulfamethoxazole, difloxacin and lincomycin/spectinomycin and 25% (n = 1) against flumequine and florfenicol. All isolates were sensitive to fosfomycin. Interestingly, all isolates (n = 4) exhibited different MAR patterns. Furthermore, the MAR index ranged from 0.45 to 0.81 CONCLUSIONS: In addition to the MAR index, which indicated that the isolate originated from a source where antibiotics were used to a great degree and/or in large amounts, the results showed that the chicken meat hosted resistant strains of Salmonella spp. in the study area. Overall, the findings indicated an important public health problem. To reduce this alarming signal, the poultry industry should implement control measures in the study area.

Comparison of drug susceptibility between Escherichia coli detected in stool cultures of patients undergoing transrectal prostate needle biopsy and Escherichia coli in hospital-wide urine antibiograms.

A prostate biopsy is essential for prostate cancer diagnosis. However, infections are one of the biopsy-associated complications, and post-biopsy fever is estimated to occur in approximately 1% of all cases. It may thus be beneficial to perform a rectal swab culture before a transrectal prostate biopsy to confirm the presence of resistant bacteria and select preventive antibacterial agents according to the drug susceptibility results. This study aimed to determine whether there is a difference between the drug susceptibility of bacteria detected in the stool of patients who were scheduled to undergo prostate biopsy and the hospital-wide urine antibiogram. Patients suspected of having prostate cancer who underwent transrectal prostate biopsy via transrectal ultrasonography between August 1, 2016, and June 30, 2020, were included in this study. Stool samples were collected and cultured before biopsy. Overall, 99 patients underwent prostate biopsy, and of these, culture results were available for 81 patients (81.8%). Escherichia coli was detected in 74.0% (60 samples) of the stool culture samples, of which 4 samples were extended-spectrum ß-lactamase-producing types. We found greater susceptibility of Escherichia coli to ampicillin, fluoroquinolones, sulfamethoxazole/trimethoprim, and cefixime in the stool culture antibiogram than in the hospital-wide urine antibiogram. We also found a significantly low incidence of ESBL-positive Escherichia coli in the stool culture antibiogram with p-values of 0.009, 0.007, and 0.03 compared to the hospital-wide urine antibiograms for 2017, 2018, and 2019, respectively. Stool culture of prostate cancer patients undergoing biopsy may provide useful information for selecting prophylactic antimicrobial agents.

Antibiotics' susceptibility patterns of bacterial isolates causing lower respiratory tract infections in ICU patients at referral hospitals in Namibia.

BACKGROUND: Lower respiratory tract infections (LRTIs) are a particular public health concern especially among sub-Saharan African countries. This is especially the case in Namibia, where LRTIs are currently the third leading cause of death, 300 deaths in children under 5 years of age. To reduce the burden of LRTIs on health systems and ensure appropriate patient management, it is critical to know the most prevalent pathogens leading to LRTIs and their susceptibility patterns in the local setting. Consequently, the objective of this study was to formulate cumulative antibiograms for Intensive Care Units (ICUs) of referral hospitals in Namibia to guide future antibiotic use. METHODS: A retrospective analytical cross-sectional study was conducted over 2 years. The cumulative antibiograms were constructed in accordance with current guidelines. RESULTS: A total of 976 first isolate cultures were obtained from ICUs of the different referral hospitals. K. pneumoniae (8.8%, 8.1%) was a predominant pathogen in Windhoek Central hospital ICU in 2017 and 2018. In Oshakati intermediate hospital ICU, Enterobacter sp. (22.2%) and P. aeruginosa (37.5%) were the common pathogens in 2017 and 2018, respectively. A. baumannii isolates were >90% susceptibility to colistin, carbapenems, and tigecycline in 2017. In 2017, K. pneumoniae isolates were more susceptible to carbapenems (94% and 93.8% among isolates), amikacin (89.3%), and tigecycline (88.7%). In 2018, K. pneumoniae isolates were 100% susceptible amikacin, colistin, and carbapenems. S. maltophilia isolates were more than 80% susceptible to all the tested antibiotics. S. aureus isolates were 100% susceptible to linezolid, rifampicin, teicoplanin, and vancomycin in 2017 and in 2018. Its susceptibility to these antibiotics did not change. CONCLUSION: The susceptibility patterns of the common isolated gram-negative pathogens were highly variable. Meropenem in combination with gentamicin is now the recommended antibiotic combination for empiric therapy for patients with LRTIs in Windhoek Central Hospital ICU.

Evaluation of Metagenomic-Enabled Antibiotic Resistance Surveillance at a Conventional Wastewater Treatment Plant.

Wastewater treatment plants (WWTPs) receive a confluence of sewage containing antimicrobials, antibiotic resistant bacteria, antibiotic resistance genes (ARGs), and pathogens and thus are a key point of interest for antibiotic resistance surveillance. WWTP monitoring has the potential to inform with respect to the antibiotic resistance status of the community served as well as the potential for ARGs to escape treatment. However, there is lack of agreement regarding suitable sampling frequencies and monitoring targets to facilitate comparison within and among individual WWTPs. The objective of this study was to comprehensively evaluate patterns in metagenomic-derived indicators of antibiotic resistance through various stages of treatment at a conventional WWTP for the purpose of informing local monitoring approaches that are also informative for global comparison. Relative abundance of total ARGs decreased by ∼50% from the influent to the effluent, with each sampling location defined by a unique resistome (i.e., total ARG) composition. However, 90% of the ARGs found in the effluent were also detected in the influent, while the effluent ARG-pathogen taxonomic linkage patterns identified in assembled metagenomes were more similar to patterns in regional clinical surveillance data than the patterns identified in the influent. Analysis of core and discriminatory resistomes and general ARG trends across the eight sampling events (i.e., tendency to be removed, increase, decrease, or be found in the effluent only), along with quantification of ARGs of clinical concern, aided in identifying candidate ARGs for surveillance. Relative resistome risk characterization further provided a comprehensive metric for predicting the relative mobility of ARGs and likelihood of being carried in pathogens and can help to prioritize where to focus future monitoring and mitigation. Most antibiotics that were subject to regional resistance testing were also found in the WWTP, with the total antibiotic load decreasing by ∼40-50%, but no strong correlations were found between antibiotics and corresponding ARGs. Overall, this study provides insight into how metagenomic data can be collected and analyzed for surveillance of antibiotic resistance at WWTPs, suggesting that effluent is a beneficial monitoring point with relevance both to the local clinical condition and for assessing efficacy of wastewater treatment in reducing risk of disseminating antibiotic resistance.

Antibiotic and Disinfectant Resistance in Tap Water Strains - Insight into the Resistance of Environmental Bacteria.

Although antibiotic-resistant bacteria (ARB) have been isolated from tap water worldwide, the knowledge of their resistance patterns is still scarce. Both horizontal and vertical gene transfer has been suggested to contribute to the resistance spread among tap water bacteria. In this study, ARB were isolated from finished water collected at two independent water treatment plants (WTPs) and tap water collected at several point-of-use taps during summer and winter sampling campaigns. A total of 24 strains were identified to genus or species level and subjected to antibiotic and disinfectant susceptibility testing. The investigated tap water ARB belonged to phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes. The majority of the isolates proved multidrug resistant and resistant to chemical disinfectant. Neither seasonal nor WTP-dependent variabilities in antibiotic or disinfectant resistance were found. Antibiotics most effective against the investigated isolates included imipenem, tetracyclines, erythromycin, and least effective - aztreonam, cefotaxime, amoxicillin, and ceftazidime. The most resistant strains originate from Afipia sp. and Methylobacterium sp. Comparing resistance patterns of isolated tap water ARB with literature reports concerning the same genera or species confirms intra-genus or even intra-specific variabilities of environmental bacteria. Neither species-specific nor acquired resistance can be excluded.

Analysis of blood stream infections, antibiograms and clinical outcomes in haematological patients with febrile neutropenia: data from a tertiary care haematology institute in India.

Timely administration of appropriate empirical antibiotics in febrile neutropenia is crucial for favourable patient outcomes. There are guidelines in place recommending such antibiotics. However, regional variations and local epidemiological data must be evaluated to tailor the antibiotics for best possible and rational use. In this study, we audited the clinical and microbiological data of febrile neutropenic episodes occurring at a tertiary care haematology institution. Three hundred and ninety-three febrile neutropenic episodes occurring in 123 patients over a 1-year period were analysed for microbial profile, sensitivity and resistance patterns, and finally clinical outcomes. Gram-negative bacilli (GNB) blood stream infections (46.9%) were more prevalent as compared to gram-positive infections (41.9%). Overall mortality due to complicated neutropenic sepsis was 19.5% (24/123 patients). Increased resistance to carbapenems, beta-lactam beta-lactamase inhibitor combinations, aminoglycosides, fluoroquinolones, and cephalosporins were observed. Cefepime and tigecycline resistance were seen in 20% and 15% GNB isolates, respectively. Chest was the most frequent focus of infection, and acute myeloid leukaemia (AML) was the most common underlying disorder which correlated with the likelihood of death (p < 0.01). Multidrug-resistant GNB (esp. Klebsiella sp.) are still most worrisome isolates in neutropenic patients. Single-agent cefepime or piperacillin-tazobactam/tigecycline combination may be considered empirical agents. Chest infections and AML were independent predictors of poor clinical outcome in neutropenic patients. Regular audit of infections and antibiotic susceptibility data is needed to improve clinical outcomes in patients with febrile neutropenia.

Diagnostic Microbiology from the Beginning to the Future: Regional Antibiograms as Public Health Tools to Slow Down Antibiotic Resistance.

Infectious diseases is the only area of medicine where we can isolate the cause and study it in the laboratory under conditions similar to human body. Once isolated, we are able to determine the most optimal drug to treat it. Unfortunately, it is also the only specialty where after making truly wondrous strides we find ourselves at the crossroads of a public health crisis in the form of ongoing antibiotic resistance. Among the factors responsible for the current status, is the suboptimal utilization of the diagnostic microbiology laboratory. In this review authors provide a short historical perspective of diagnostic microbiology. The focus of discussion is the generation and utilization of cumulative antibiograms at the institutional and regional levels and discuss the pitfalls in large national databases with respect to the day-to-day patient care. This public health tool to slow down antibiotic resistance happens to be low-tech and inexpensive.

Amoxicillin and amoxicillin-clavulanate resistance in urinary Escherichia coli antibiograms of cats and dogs from the Midwestern United States.

BACKGROUND: Antibiograms are stewardship tools that provide antimicrobial resistance data for regional bacterial isolates to guide treatment of infections. OBJECTIVES: To develop regional antibiograms of urinary Escherichia coli isolates from cats and dogs. ANIMALS: Escherichia coli isolates cultured from feline (N = 143) and canine (640) urine from 2013 to 2017, from Kansas State University (N = 335) and private practice (N = 448) patients in the Midwestern United States. METHODS: Retrospective review of urine culture and susceptibility results. Antibiograms were created for 10 commonly used antimicrobial agents using Clinical and Laboratory Standards Institutes guidelines. RESULTS: No isolates from cats were susceptible to amoxicillin-clavulanate (susceptibility [S] ≤ 0.25/0.12) or amoxicillin (S ≤ 0.25); isolates from dogs had low susceptibility to amoxicillin 53% (S ≤ 8). Conversely, isolates from dogs had high susceptibility to amoxicillin-clavulanate 92% (S ≤ 8/4), despite equal 90th percentile minimum inhibitory concentrations (8 µg/mL) for feline and canine populations. Resistance to other antimicrobials was uncommon (≤7% for isolates from cats, ≤14% for isolates from dogs). CONCLUSIONS AND CLINICAL IMPORTANCE: The disparity in susceptibility for amoxicillin and amoxicillin-clavulanate between isolates from cats and dogs likely reflects higher breakpoints for urinary tract infections (UTIs) in dogs. Urine concentration data for these antimicrobials in cats might support a UTI-specific breakpoint for cats and increase potential therapeutic options for managing UTIs in cats with first-line antimicrobials. Decreased susceptibility among isolates from dogs to amoxicillin (53%) compared to amoxicillin-clavulanate (92%) might support amoxicillin-clavulanate as a better empirical choice for UTIs in dogs in this geographical region.

Prevalence and antibiotic susceptibility patterns of enteric bacterial pathogens in human and non-human sources in an urban informal settlement in Cape Town, South Africa.

BACKGROUND: In light of rampant childhood diarrhoea, this study investigated bacterial pathogens from human and non-human sources in an urban informal settlement. Meat from informal abattoirs (n = 85), river water (n = 64), and diarrheic stool (n = 66) were collected between September 2015 and May 2016. A duplex real-time PCR, gel-based PCR, and CHROMagar™STEC were used to screen Tryptic Soy Broth (TSB) for diarrheic E. coli. Standard methods were used to screen for other selected food and waterborne bacterial pathogens. RESULTS: Pathogens isolated from stool, meat, and surface water included Salmonella enterica (6, 5, 0%), Plesiomonas shigelloides (9, 0, 17%), Aeromonas sobria (3, 3, 0%), Campylobacter jejuni (5, 5, 0%), Shigella flexneri (17, 5, 0%), Vibrio vulnificus (0, 0, 9%), and diarrheic E. coli (21, 3, 7%) respectively. All the isolates were resistant to trimethoprim-sulphamethoxazole. CONCLUSIONS: There was a high burden of drug resistant diarrheal pathogens in the stool, surface water and meat from informal slaughter. Integrated control measures are needed to ensure food safety and to prevent the spread of drug resistant pathogens in similar settings.

Antibiogram and molecular characterization of methicillin-resistant Staphylococcus aureus recovered from treated wastewater effluent and receiving surface water in Durban, South Africa.

Municipal wastewater treatment plants (WWTPs) may serve as a reservoir for potentially pathogenic and antibiotic resistant bacteria. The discharge of improperly treated wastewater effluent may lead to the spread of these bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) which is responsible for causing pneumonia, septicaemia and skin and soft tissue infections, into the receiving surface waters. This study aimed to determine the antibiogram and virulence gene profiles of MRSA isolates recovered from treated wastewater effluent and receiving surface waters. Genetic fingerprinting of the isolates was also carried out to determine the phylogenetic relationship between the isolates and selected antibiogram profiles. Eighty MRSA isolates were obtained from treated effluent and receiving rivers of two WWTPs in Durban, KwaZulu-Natal. Antibiotic resistance was observed towards lincomycin (100%), oxacillin (98.75%), cefoxitin and penicillin (97.50%), and ampicillin (96.25%). In addition, 72.50%, 66.25%, 52.50%, 40% and 33.75% of isolates showed resistance against cefozolin, azithromycin, amoxicillin/clavulanic acid, erythromycin and vancomycin, respectively. Antibiotic resistance genes detected in the isolates tested in this study: aac(6')/aph(2″) (56.25%), ermC (62.50%), msrA (22.50%), and blaZ and tetK (70%). The frequency of virulence genes: hla and sea was 57.50%, hld was 1.25%, while lukS P/V was 0%. Pulse Field Gel Electrophoresis analysis generated 13 pulsotypes (designated A-M) showing a correlation to their respective antibiograms. Findings from this study showed the presence of potentially pathogenic, multi-drug resistant MRSA in the treated effluent and receiving surface waters. This may have detrimental effects on the health of individuals who come into contact with these water resources.

Potential Impact of Hospital-acquired Pneumonia Guidelines on Empiric Antibiotics. An Evaluation of 113 Veterans Affairs Medical Centers.

Rationale: The 2016 guidelines for hospital-acquired pneumonia (HAP) suggest applying a universal antibiogram resistance threshold in addition to patient criteria to determine empiric coverage. The impact of these recommendations is unknown.Objectives:1) Describe national antibiotic use and microbiology patterns for HAP among patients with noninfectious admissions, 2) measure the predictive performance of the antibiogram threshold and risk factors, and 3) estimate the change in practice with guideline implementation.Methods: We conducted a retrospective analysis of all hospitalizations without initial infection but with secondary pneumonia diagnoses at Veterans Affairs Medical Centers between October 1, 2012, and September 30, 2015. For each hospitalization we extracted: presence of methicillin-resistant Staphylococcus aureus (MRSA) and resistant gram-negative rods (R-GNR) in cultures, anti-MRSA and antipseudomonal antimicrobial administration, and facility-level prevalence of MRSA and R-GNR. We calculated the percentage of hospitalizations with resistant organisms, broad-spectrum antibiotics, and the predictive performance of patient characteristics and prevalence thresholds for MRSA.Results: Among 3,562 cases, 5.17% were positive for MRSA and 2.30% for R-GNR. The recommended MRSA prevalence threshold was 100.00% sensitive (95% confidence interval [CI], 98.02-100.00%) and 0.03% specific (95% CI, 0.00-0.16%) for MRSA-positive culture, leading to overtreatment of 94.81% (95% CI, 94.02-95.50%) of patients. Pressor order (odds ratio [OR], 3.89; 95% CI, 1.17-12.91) and intravenous antibiotics within the past 90 days (OR, 1.98; 95% CI, 1.03-3.81) were associated with MRSA. Mechanical ventilation was associated with R-GNR (OR, 4.37; 95% CI, 1.52-12.57).Conclusions: The guideline-recommended antibiogram threshold and characteristics did not improve prediction of MRSA or R-GNR and would have led to an increase in MRSA treatment.