High Rates Of Antibiotic Resistance Research Articles

Reducing Duration of Antibiotic Use for Presumed Neonatal Early-Onset Sepsis in Greek NICUs. A "Low-Hanging Fruit" Approach.

Antibiotics are commonly prescribed in Neonatal Intensive Care Units (NICU), where stewardship interventions are challenging. Lowering antibiotic consumption is desperately needed in Greece, a country with high antibiotic resistance rates. We sought to assess the effectiveness of a low-cost and -resource intervention to reduce antibiotic use in Greek NICUs implementing a “low-hanging fruit” approach. A prospective quasi-experimental study was conducted in 15/17 public NICUs in Greece (9/2016–06/2019). The intervention selected was discontinuation of antibiotics within 5 days for neonates with gestational age ≥ 37 weeks, no documented signs or symptoms of sepsis, CRP ≤ 10 mg/L and negative cultures within 3 days of antibiotic initiation. Impact was evaluated by the percentage of discontinued regimens by day 5, length of therapy (LOT) and stay. Trends of antibiotic consumption were assessed with days of therapy (DOT) per 1000 patient-days. Overall, there was a 9% increase (p = 0.003) of antibiotic discontinuation in ≤5 days. In total, 7/13 (53.8%) units showed a ≥10% increase. Overall, 615 days on antibiotics per 1000 patients were saved. Interrupted time-series analysis established a declining trend in DOT/1000 patient-days relative to the pre-intervention trend (p = 0.002); a monthly decrease rate of 28.96 DOT/1000 patient-days (p = 0.001, 95%CI [−45.33, −12.60]). The intervention had no impact on antibiotic choice. Antibiotic use was successfully reduced in Greek NICUs using a “low-hanging fruit” approach. In resource-limited settings, similar targeted stewardship interventions can be applied.

Activity of Imipenem, Meropenem, Cefepime, and Sulbactam in Combination with the β-Lactamase Inhibitor LN-1-255 against Acinetobacter spp.

Treatment of infections caused by Acinetobacter spp., particularly A. baumannii, is a major clinical problem due to its high rates of antibiotic resistance. New strategies must be developed; therefore, restoration of β-lactam efficacy through the use of β-lactamase inhibitors is paramount. Activities of the antibiotics imipenem, meropenem, cefepime, and sulbactam in combination with the penicillin-sulfone inhibitor LN-1-255 were tested by microdilution against 148 isolates of Acinetobacter spp. collected in 14 hospitals in Spain in 2020. Relevantly, the MIC90 (i.e., minimum concentration at which 90% of isolates were inhibited) of antibiotics in combination with LN-1-255 decreased 4- to 8-fold for all of the Acinetobacter isolates. Considering only the carbapenem-resistant A. baumannii isolates, which produce carbapenem-hydrolyzing class D β-lactamases, the addition of LN-1-255 decreased the resistance rates from 95.1% to 0% for imipenem, from 100% to 9.8% for meropenem, from 70.7% to 7.3% for cefepime, and sulbactam resistance rates from 9.8% to 0% and intermediate susceptibility rates from 53.7% to 2.4%. The inhibitor also decreased the minimum inhibitory concentrations (MICs) when tested against non-carbapenem-resistant Acinetobacter spp. isolates. In conclusion, combining LN-1-255 with imipenem, meropenem, cefepime, and sulbactam to target A. baumannii, and especially carbapenem-resistant isolates, represents an attractive option that should be developed for the treatment of infections caused by this pathogen.

Chances and prevention of antibiotic resistance in primary health care: literature review

Many concerns have been expressed in the field of clinical practice regarding antimicrobial resistance since many infections with severe complications and bad prognosis have been described since the end of the last century. In primary healthcare facilities, the risks for developing high rates of antibiotic resistance is high, probably due to the high prevalence of bacterial infections in these places, and due to the overuse of antibiotics without any relevance of evidence of bacterial infections. For instance, people usually administer high doses of broad-spectrum antibiotics for non-severe, self-limiting respiratory tract infections. Moreover, for fighting bacterial infections, patients usually discontinue the treatment course once the symptoms of the disease were relieved. These factors among many others had led to the high prevalence of antibiotic resistance which may lead to serious complications. Many approaches are being made to reduce the resistance that has been reviewed in this review. These include optimizing the dosage and timing of antibiotics administration which can be achieved by more understanding of the pharmacology of the antibiotics. Moreover, training and education programs that target the prescribers and patients have been proven to be efficient in reducing the rates. These efforts are encouraged to last and target more people for more favorable outcomes.

Antimicrobial Resistance in Enterobacterales and Its Contribution to Sepsis in Sub-saharan Africa.

Antibiotic resistant Enterobacterales (formerly Enterobactereaceae) are a growing threat to Sub-Saharan Africa. Genes causing antibiotic resistance are easily spread between the environment and humans and infections due to drug resistant organisms contribute to sepsis mortality via delayed time to appropriate antimicrobial therapy. Additionally, second or third-line antibiotics are often not available or are prohibitively expensive in resource-constrained settings leading to limited treatment options. Lack of access to water and sanitation facilities, unregulated use of antibiotics, and malnutrition are contributors to high rates of antibiotic resistance in the region. Improvements in the monitoring of drug resistant infections and antibiotic stewardship are needed to preserve the efficacy of antibiotics for the future.

Urinary tract infection in HIV-positive women

Introduction: Urinary tract infections (UTI) are common in women and can cause systemic repercussions. In pregnant women, for example, the occurrence of UTI or asymptomatic bacteriuria (AB) can lead to premature birth and fetal death. The generalized immune depletion caused by HIV is related to the exacerbation of infections, and may be related to UTI. Objective: The objective of this review was to evaluate the characteristics of UTI in pregnant and non-pregnant HIV-positive women as well as the factors that interfere in its occurrence. Methods: By searching the databases PubMed, Web of Science, Scielo and Lilacs, we selected eleven articles that correlated UTI and HIV infection in women. Results: Our analysis showed that HIV-positive pregnant women have a higher predisposition to UTI than HIV-negative ones. The Viral Load (VL) is directly related to UTI and AB in HIV-positive non-pregnant women. TCD4 lymphocyte levels (TCD4) lower than 200 cells/mL and VL over 10,000 copies/mL are correlated with higher UTI and AB rates in HIV-positive pregnant women. There is a tendency for greater variability of pathogens in HIV-positive women and a predisposition to higher rates of antibiotic resistance in HIV-positive pregnant women. Conclusion: HIV-positive pregnant women have higher predisposition to urinary tract infection and its incidence is correlated with a high viral load and a low TCD4 count.

Study of biofilm formation, structure and antibiotic resistance in Staphylococcus saprophyticus strains causing urinary tract infection in women in Ahvaz, Iran

Staphylococcus saprophyticus is the second most frequent community-acquired causative agent of acute urinary tract infection (UTI). Some strains of S. saprophyticus can create biofilms, increasing their virulence. Once biofilms have been produced, antibiotic resistance is exacerbated. Hence, the aims of the present study were the study of biofilm formation, structure and antibiotic resistance in S. saprophyticus strains causing UTIs in women in Ahvaz, Iran. Overall, 43 S. saprophyticus isolates were recovered from UTIs. Antibiotic resistance pattern and the biofilm production and structure were determined using phenotypic methods. Most S. saprophyticus isolates were resistant to erythromycin, but all isolates were sensitive to linezolid and vancomycin. Fifty-eight per cent of S. saprophyticus were multidrug resistant. Twenty-one per cent of S. saprophyticus isolates harbored the mecA gene. Biofilm formation was observed in 65% of S. saprophyticus isolates and most had polysaccharide matrix. Our data indicate high rates of antibiotic resistance and the capability of biofilm formation among S. saprophyticus isolates. The emergence of antibiotic resistance in the management of UTIs is a serious public health issue. The findings of this study could be used to improve treatment plans to control UTIs. Consequently, increased awareness of the mechanisms underlying biofilm formation and the development of drug resistance will allow UTIs to be more efficiently controlled and treated.

Bacteriophages of Helicobacter pylori.

The bacterium Helicobacter pylori colonize the stomach in approximately half of the world’s population. Infection with this bacterium is associated with gastritis, peptic ulcer, adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Besides being a pathogen with worldwide prevalence, H. pylori show increasingly high antibiotic resistance rates, making the development of new therapeutic strategies against this bacterium challenging. Furthermore, H. pylori is a genetically diverse bacterium, which may be influenced by the presence of mobile genomic elements, including prophages. In this review, we analyze these issues and summarize various reports and findings related to phages and H. pylori, discussing the relationship between the presence of these elements and the genomic diversity, virulence, and fitness of this bacterium. We also analyze the state of the knowledge on the potential utility of bacteriophages as a therapeutic strategy for H. pylori.

Pharmacology, Dosing, and Side Effects of Rifabutin as a Possible Therapy for Antibiotic-Resistant Acinetobacter Infections.

Acinetobacter baumannii has among the highest rates of antibiotic resistance encountered in hospitals. New therapies are critically needed. We found that rifabutin has previously unrecognized hyperactivity against most strains of A. baumannii. Here we review the pharmacology and adverse effects of rifabutin to inform potential oral dosing strategies in patients with A. baumannii infections. Rifabutin demonstrates dose-dependent increases in blood levels up to 900 mg per day, but plateaus thereafter. Furthermore, rifabutin induces its own metabolism after prolonged dosing, lowering its blood levels. Pending future development of an intravenous formulation, a rifabutin oral dose of 900–1200 mg per day for 1 week is a rational choice for adjunctive therapy of A. baumannii infections. This dosage maximizes AUC24 to drive efficacy while simultaneously minimizing toxicity. Randomized controlled trials will be needed to definitively establish the safety and efficacy of rifabutin to treat A. baumannii infections.

Friend or Foe: Perceptions of Infectious Disease Specialists as Stewards and Social Determinants of Antimicrobial Prescribing

Background: Inappropriate prescribing behavior can be associated with higher rates of antibiotic resistance, calling for detailed studies on how physicians make prescribing decisions. We conducted a mixed-methods study to investigate physician antibiotic prescribing behavior in a 141-bed pediatric hospital. Methods: We applied a mixed-methods research design. The quantitative phase was conducted over a 6-month period to identify cases of inappropriate prescribing. The qualitative phase comprised 22 qualitative interviews with clinical teaching units (CTU) and pediatric intensive care unit (PICU) team members (physicians and pharmacists). Two coders analyzed the data deductively using the theoretical domain framework (TDF), as well as the social determinants of antimicrobial prescribing (SDAP). Results: In 52.9% of the 36 identified cases in the CTU and 31.4% of the 37 cases in the PICU, an infectious diseases (ID) consultation occurred. Compliance rates with ID recommendations were 79% and 91% in the CTU and PICU, respectively. The CTU and PICU expressed appreciation for ID involvement when ID supported their de-escalation choices in complex cases and in cases in which less commonly known antibiotics were used. However, the ID service involvement was perceived as detrimental to antimicrobial prescribing decisions for CTU and PICU across 3 of the 4 SDAP domains (Fig. 1, qualitative research quotes). Relationship between clinicians: CTU physicians and pharmacists perceived ID involvement as negatively impacting the relationship of the team. Antimicrobial decisions were automatically defaulted to ID, whereas pharmacy involvement was disregarded and the decisions were delayed. Risk, fear, and emotion: These were experienced across all respondents’ groups that identified ID specialists’ egos and personalities as contrary to open collaborative discussion on antimicrobial decisions. (Mis)perception of the problem: ID physicians were identified as more conservative in their antimicrobial choices, leading to prolonged duration of treatment, broader choices, and longer hospitalizations. The CTU and pharmacy respondents felt that ID recommendations were inconsistent among physicians and deviated from guidelines with little justification. Conclusions: Although CTU and PICU teams tend to comply with ID prescribing recommendations and ID involvement with complicated cases, pharmacists, CTU physicians, and PICU physicians perceived ID consultations to negatively affect collaborative efforts for stewardship. These findings offer novel insights into how an ID service can improve its role to positively affect appropriate prescribing. CTU and PICU respondents called for a supportive and trusting relationship with the ID service as a major driver for behavioral change and enhanced stewardship.Funding: NoneDisclosures: None

Highly clonal relationship among Salmonella Enteritidis isolates in a commercial chicken production chain, Brazil.

In this study, we described the comparison among pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD), ribotyping, and PCR-ribotyping methods for subtyping Salmonella Enteritidis isolated from an industrial chicken production chain. One hundred and eight S. Enteritidis were isolated at all stages of poultry meat processing plant. These isolates were pheno- and genotypically characterized by using antimicrobial susceptibility test, phage typing, RAPD, PFGE, ribotyping, and PCR-ribotyping. The highest antibiotic resistance rates were observed for enrofloxacin (18.5%) followed by furazolidone (15.7%), cefoxitin (1.8%), ciprofloxacin, and ampicillin with 0.9% each one, while seven isolates (6.4%) were pan-susceptible. Most strains belonged to the globally disseminated phage type PT4 (n = 74; 69.2%). Additionally, we identified strains belonging to phage types PT1 (n = 19; 17.8%) and PT7a (n = 14; 13.1%). Moreover, our results showed that these four molecular methods indicate similar results showing high similarity (≥ 90%) among S. Enteritidis strains, suggesting that these isolates appear to be from a common ancestor being spread at all stages of the poultry production chain. In summary, the combined molecular approaches of these methods remain a suitable alternative to efficiently subtyping S. Enteritidis in the absence of high-resolution genotyping methods and these results may serve as a baseline study for development of mitigation strategies.

Cranberry Polyphenols and Prevention against Urinary Tract Infections: Relevant Considerations.

Cranberry (Vaccinium macrocarpon) is a distinctive source of polyphenols as flavonoids and phenolic acids that has been described to display beneficial effects against urinary tract infections (UTIs), the second most common type of infections worldwide. UTIs can lead to significant morbidity, especially in healthy females due to high rates of recurrence and antibiotic resistance. Strategies and therapeutic alternatives to antibiotics for prophylaxis and treatment against UTIs are continuously being sought after. Different to cranberry, which have been widely recommended in traditional medicine for UTIs prophylaxis, probiotics have emerged as a new alternative to the use of antibiotics against these infections and are the subject of new research in this area. Besides uropathogenic Escherichia coli (UPEC), the most common bacteria causing uncomplicated UTIs, other etiological agents, such as Klebsiella pneumoniae or Gram-positive bacteria of Enterococcus and Staphylococcus genera, seem to be more widespread than previously appreciated. Considerable current effort is also devoted to the still-unraveled mechanisms that are behind the UTI-protective effects of cranberry, probiotics and their new combined formulations. All these current topics in the understanding of the protective effects of cranberry against UTIs are reviewed in this paper. Further progresses expected in the coming years in these fields are also discussed.

First UTI episode in life in infants

To examine the epidemiologic and microbiologic characteristics of first and recurrent UTI in young infants. A retrospective study of all infants <1 year hospitalized during 2014-2017 with their first UTI and followed during their first year of life. 191 infants were enrolled; 69 (36.12%) patients were <2 months and 32 (16.8%) developed R-UTI during the follow-up. The five most common uropathogens were Escherichia coli, Klebsiella spp., Enterococcus spp., Proteus mirabilis and Staphylococcus aureus. High resistance rates were recorded for ampicillin, amoxicillin/clavulanic acid, TMP/SMX, cefuroxime, ceftriaxone, piperacillin/tazobactam and gentamicin among E. coli and Klebsiella spp.; 29.15% E. coli and 42.9% Klebsiella spp. were ESBL-positive. 53.2% of recurrent UTI (R-UTI) episodes were diagnosed within 2 months after the initial UTI episode. E. coli (40.6%) and Klebsiella spp. (37.55) were the most frequent R-UTI pathogens. Twenty-five (78.1%) R-UTIs were caused by recurrent uropathogens representing new infections. Antibiotic resistance rates at recurrence were similar to those at initial UTI, except for a significant increase in E. coli and Klebsiella spp. resistance to piperacillin/tazobactam. We reported high antibiotic resistance rates to major antibiotic classes used in UTI treatment. Most R-UTI episodes were caused by uropathogens different than those isolated at the initial UTI episode and were caused by highly-resistant organisms. Our findings require frequent monitoring and possible modification of the empiric and prophylactic antibiotic therapy protocols in use. As a result of our findings, the protocol for initial empiric treatment of infants with suspicion of UTI was modified by changing gentamicin to amikacin in the treatment of infants <2 months of life and amikacin monotherapy (intravenous or intramuscular) was introduced as first-line therapy for infants >2 months of life.

Efficacy of a Novel Ophthalmic Antimicrobial Drug Combination Toward a Large Panel of Staphylococcus aureus Clinical Ocular Isolates From Around the World.

Staphylococcus aureus is a leading cause of keratitis requiring urgent antimicrobial treatment. However, rising antibiotic resistance has rendered current ophthalmic antibiotics increasingly ineffective. First, a diverse, ocular S. aureus strain set was evaluated for resistance to 6 commonly used ophthalmic antibiotics. Next, a recently discovered antimicrobial drug combination containing polymyxin B/trimethoprim (PT) + rifampin that displayed impressive efficacy toward S. aureus in both in vitro and in vivo studies was evaluated as a potential novel keratitis therapeutic through testing this combination's efficacy against the clinical strain set. A total of 163 S. aureus isolates were collected either commercially or from the Flaum Eye Institute, University of Rochester. The minimum inhibitory concentrations of moxifloxacin, levofloxacin, vancomycin, erythromycin, tobramycin, rifampin, and PT were determined for the entire strain set to establish the incidence of resistance to current treatment options among a contemporary clinical isolate set and compared with the performance of PT + rifampin. Among all 163 isolates tested, high rates of antibiotic resistance were found toward erythromycin (69% resistance), moxifloxacin (33%), levofloxacin (40%), and tobramycin (17%). Conversely, the entire strain set, including multidrug resistant isolates, was sensitive to PT + rifampin, demonstrating the potency of this combination. We established that antibiotic resistance is pervasive among clinical S. aureus isolates, underscoring the concern for the effectiveness of current ophthalmic antibiotics. The drug combination of PT + rifampin, however, eradicated 100% of isolates tested, demonstrating the ability to overcome existing circulating resistance factors, and as such, might represent a promising therapeutic for S. aureus keratitis.

Bacterial spectrum and antibiotic resistance of urinary tract infections in patients treated for upper urinary tract calculi: a multicenter analysis.

The purpose of this study is to collect information on the bacterial resistance to antibiotics of bacteria isolated from urine cultures of patients treated for upper urinary tract calculi. Data of patients with urinary tract infection and urolithiasis were retrospectively reviewed to collect information on age, gender, stone size, location, hydronephrosis, procedure of stone removal and antibiotic treatment, identification and susceptibility of pathogens, symptoms, and infectious complications. A total of 912 patients from 11 centers in 7 countries (Bulgaria, Greece, Italy, North Macedonia, Spain, and Turkey) were studied. Mean age was 54 ± 16years and M/F ratio 322/590. Out of 946 microbial isolates, the most common were E. coli, Gram-positive, KES group (Klebsiella, Enterobacter, Serratia), Proteus spp., and P. aeruginosa. Carbapenems, piperacillin/tazobactam and amikacin showed low resistance rates to E. coli (2.5%, 7%, and 3.6%) and Proteus spp. (7.7%, 16%, and 7.4%), but higher rates were observed with Klebsiella spp., P. aeruginosa, and Gram-positive. Fosfomycin had resistance rates less than 10% to E. coli, 23% to KES group, and 19% to Gram-positive. Amoxicillin/clavulanate, cephalosporins, quinolones, and TMP/SMX showed high resistance rates to most bacterial strains. High rates of antibiotic resistance were observed in patients candidate to stone treatment from South-Eastern Europe. The empirical use of antibiotics with low resistance rates should be reserved to the most serious cases to avoid the increase of multidrug resistant bacteria. Basing on our results, carbapenems, piperacillin/tazobactam, and amikacin may be a possible option for empiric treatment of urinary stone patients showing systemic symptoms.

Anatomical site-specific immunomodulation by bacterial biofilms.

The human body plays host to bacterial biofilms across diverse anatomical sites. The treatment of pathogenic biofilm infection is confounded by their high rate of antibiotic resistance. Therefore, it is critical to understand the interplay between these biofilms and the host immune system to develop new tactics to combat these infections. Bacterial biofilms and the components they produce affect and are affected by the host immune system. Host anatomical sites represent distinct niches in which defined bacterial biofilms are able to form and interact with the host immune system. For persistent colonization to occur, the bacteria must either avoid or suppress the host immune system, or induce an immune response that facilitates their perpetuation. Commensal bacterial biofilms form a protective barrier against colonization by pathogens. Using similar mechanisms, bacteria modulate the immune system to orchestrate persistence and sometimes disease. Clinicians must balance the need to avoid disturbing beneficial commensal biofilms with the difficulty in preventing or treating pathogenic bacterial biofilms such as those that develop on medical implants and open wounds.

Mapping the microbiological diversity of odontogenic abscess: are we using the right drugs?

The aim of this study was categorizing the microbial flora and susceptibility to antibiotics and to clarify to which degree the empiric administered antibiotics are suitable for therapy. A 3.5-year retrospective study evaluated hospital records of 206 patients who suffered from head and neck infections of odontogenic origin. All patients underwent surgical incision and drainage and received intravenous antibiotics and inpatient treatment. The specimens were obtained by performing a swab. Two hundred six patients were included with 251 strains isolated (1.22 per patient). One hundred eight strains showed antibiotic resistance. Eighty-seven patients showed at least one bacterial strain that showed antibiotic resistance (42.2%). The most frequent isolated bacteria were Streptococcus spp. (n = 116), with a high rate of antibiotic resistance (50.8%). We investigated 205 cases of antibiotic resistance in 87 subjects. Nine bacterial strains showed no susceptibility to unacid (4.3%) and 36 strains to clindamycin (17.5%). Antibiotic resistance against clindamycin was rather high. The distribution of the afflicted spaces and isolated bacteria was alike recent findings. It is mandatory to understand that immediate surgical treatment in terms of incision and drainage is the basis in abscess treatment. Antibiotic treatment is adjunct therapy. Streptococcus species were the most frequently identified bacteria presenting antibiotic resistance in more than 50%. Increased resistant rates for clindamycin require reconsiderations regarding an empiric antibiotic treatment.

High rates of antibiotic resistance and biofilm production in Escherichia coli isolates from food products of animal and vegetable origins in Tunisia: a real threat to human health

ABSTRACT The aim of this study was to compare the antibiotic susceptibility of eighty Escherichia coli isolates from vegetables and food products of animal origin in Tunisia, and to study their genes encoding antibiotic resistance and in vitro biofilm forming capacity. Antimicrobial susceptibilities were determined, as well as PCR investigation of genes associated with antibiotic resistance. Biofilm formation was tested using four different methods: the microtiter plate-, MTT-staining-, XTT-staining-, and the Congo Red Agar assays. High antibiotic resistance rates were observed for amoxicillin (68.7%), amoxicillin/clavulanic acid (73.7%), gentamicin (68.7%), kanamycin (66.2%), nalidixic acid (36.2%), streptomycin (68.7%) and tetracycline (35%). The majority of isolates was multidrug resistant and biofilm producer. MTT testing showed that vegetables isolates were significantly higher biofilm producers compared to foods of animal origins. This study showed that E. coli isolates from food products were reservoirs of genes encoding antibiotic-resistance and have a high propensity to produce biofilm.

Antimicrobial Resistance and Presence of Class 1 Integrons Among Different Serotypes of Salmonella spp. Recovered From Children with Diarrhea in Tehran, Iran

Salmonellosis is a major food-borne disease worldwide. The increasing prevalence of antimicrobial resistance among food-borne pathogens such as Salmonella spp. is concerning. The main objective of this study is to identify class 1 integron genes and to determine antibiotic resistance patterns among Salmonella isolates from children with diarrhea. A total of 30 Salmonella isolates were recovered from children with diarrhea. The isolates were characterized for antimicrobial susceptibility and screened for the presence of class 1 integron genes (i.e. intI1, sulI1, and qacEΔ1). The most prevalent serotype was Enteritidis 36.7%, followed by Paratyphi C (30%), and Typhimurium (16.7%). The highest rates of antibiotic resistance were obtained for nalidixic acid (53.3%), followed by streptomycin (40%), and tetracycline (36.7%). Regarding class 1 integrons, 36.7%, 26.7%, and 33.3% of the isolates carried intI1, SulI, and qacEΔ1, respectively, most of which (81.8%) were multidrug-resistant (MDR). Statistical analysis revealed that the presence of class 1 integron was significantly associated with resistance to streptomycin and tetracycline (p = 0.042). However, there was no association between class 1 integron and other antibiotics used in this study (p > 0.05). The high frequency of integron class 1 gene in MDR Salmonella strains indicates that these mobile genetic elements are versatile among different Salmonella serotypes, and associated with reduced susceptibility to many antimicrobials.

Guideline-based treatment of urinary tract infections

Urinary tract infections (UTIs) are among the most common infections. Especially complicated UTIs have abroad bacterial spectrum, sometimes having high antibiotic resistance rates. The clinical course might be very different and can range from spontaneous cure to fulminant sepsis. Which initial therapy is adequate for which UTI entity and what are the corresponding guidelines recommendations? This is areview of the current S3 guideline urinary tract infection, the guideline parenteral initial therapy of bacterial infections from the Paul Ehrlich Society, the guideline urological infections from the European Association of Urology (EAU) and the guideline on recurrent uncomplicated UTI in women from the American Urological Association (AUA). Adequate antibiotic therapy is based on the stratification into complicated and uncomplicated, as well as upper and lower infections, and on specific risk factors (e.g., urinary tract catheter) that can be classified according to the ORENUC criteria. Based on this classification, the choice for an empirical antibiotic therapy is made. The spectrum of pathogens should therefore be limited in order to use antibiotics with anarrow spectrum of activity and little collateral damage if possible, thus, preventing both the development of resistance and complications. Adequate empirical antibiotic therapy and prophylaxis in line with guidelines is based on the clinical classification and risk factors.

Microbiology of total knee arthroplasty

Objective: The aim of the study identify the common organism causing Prosthetic Joint Infection (PJI) and the drug resistance spectrum of the most common organisms causing PJI, to help in choosing appropriate antibiotics. Methods: The study was a retrospective study of the patients who received revision and re-revision of total knee arthroplasty for different reasons in our institution from August 2016 to August 2019. The isolated bacteria strains and drug-resistance rates for each pathogen for different antibiotics were presented. Results: There were 36 cases in the infectious group and 29 cases in the non-infectious group (PJI was diagnosed according to the diagnosing criteria from the Workgroup of the Musculoskeletal Infection Society). Of the 36 strains isolated, Gram-positive bacteria were the most common pathogenic organisms. Staphylococcus aureus (11, 39.28%) was the most common pathogen followed by Staphylococcus epidermidis (7, 25.00%) and Corynebacterium (5, 17.86%). Penicillin (86.11%), erythromycin (50.00%) and clindamycin (53.37%) showed high antibiotic resistance rate. In addition, the second-generation cephalosporins, usually as the prophylactic antibiotic, resistance rate was high (20%).Conclusion: This study provides some information on the most common organisms at our institution and the selection of antibiotics in the peri-operative period. Cefuroxime and clindamycin might not be appropriate for use as prophylactic antibiotics in revision total knee or hip arthroplasty. Vancomycin is ideal for empiric antibiotic use in suspected PJI cases because of the low drug-resistance rate.