Empiric antibiotic treatment and the misuse of culture results and antibiotic sensitivities in patients with community-acquired bacteraemia due to urinary tract infection

Characterizing Antibiotic Regimen Modification Behavior, Patient Characteristics, and Outcomes for Patients with Gram-Negative Bacterial Infections, A Retrospective Single-Center Study

Few studies describe the frequency of antibiotic regimen modification behaviors in the acute care setting. We sought to ascertain patient and treatment characteristics, details of regimen modification, and clinical outcomes with antibiotic modifications. This retrospective study included patients admitted to Hoag Memorial Hospital from 1 January 2019-31 March 2021 with a complicated infection caused by a Gram-negative organism resistant to extended-spectrum cephalosporins or with the potential for resistance (AmpC producers). A total of 400 patients were included. The predominant sources were bloodstream (33%), urine (26%), and respiratory (24%), including patients with multiple sources. The most isolated organisms were Pseudomonas spp. and ESBL-producing organisms, 38% and 34%, respectively. A total of 72% of patients had antibiotic regimen modifications to their inpatient antibiotic regimens. In patients where modifications occurred, the number ranged from one to six modifications. The most common reasons for modifications included a lack of patient response (14%), additional history reviewed (9%), and decompensation (7%). No difference in clinical outcomes was observed based on antibiotic modifications. The numerous changes in therapy observed may reflect the limitations in identifying patients with resistant organisms early on in admission. This highlights the need for more novel antibiotics and the importance of identifying patients at risk for resistant organisms.

A 2-Year Audit on Antibiotic Resistance Patterns from a Urology Department in Greece

PURPOSE

The high incidence of urinary tract infections (UTIs), often in nosocomial environments, is a major cause of antimicrobial resistance (AMR). The dissemination of antibiotic-resistant infections results in very high health and economic burdens for patients and healthcare systems, respectively. This study aims to determine and present the antibiotic resistance profiles of the most common pathogens in a urology department in Greece.

METHODS

During the period 2019-2020, we included 12,215 clinical samples of blood and urine specimens that tested positive for the following pathogens: Escherichia coli, Enterococcus faecium, Enterococcus faecalis, Proteus mirabilis, Klebsiella pneumoniae, or Pseudomonas aeruginosa, as these are the most commonly encountered microbes in a urology department.

RESULTS

The analysis revealed a 22.30% mean resistance rate of E. coli strains with a 76.42% resistance to ampicillin and a 54.76% resistance rate to ciprofloxacin in the two-year period. It also showed an approximately 19% resistance rate of P. mirabilis strains and a mean resistance rate of 46.205% of K. pneumoniae strains, with a decreasing trend during the four semesters (p-value < 0.001), which presented an 80% resistance rate to ampicillin/sulbactam and 73.33% to ciprofloxacin. The resistance to carbapenems was reported to be 39.82%. The analysis revealed a 24.17% mean resistance rate of P. aeruginosa with a declining rate over the two-year period (p-value < 0.001). The P. aeruginosa strains were 38% resistant to fluoroquinolones and presented varying resistance against carbapenems (31.58% against doripenem and 19.79% against meropenem). Regarding the Enteroccocal strains, a 46.91% mean resistance was noted for E. faecium with 100% resistance to ampicillin, and a 24.247% mean resistance rate for E. faecalis strains that were 41% resistant to ciprofloxacin. Both types showed 100% sensitivity to linezolid.

CONCLUSIONS

The dissemination of antibiotic-resistant pathogens poses the need to implement surveillance programs and, consequently, to develop strategies to prevent the emergence of such pathogens in order to optimize patient outcomes.

The Role of Biomarkers and Scores in Describing Urosepsis

Background and Objectives: Patients with urinary tract obstruction (UTO) and systemic inflammatory response syndrome (SIRS) are at risk of developing urosepsis, whose evolution involves increased morbidity, mortality and cost. The aim of this study is to evaluate the ability of already existing scores and biomarkers to diagnose, describe the clinical status, and predict the evolution of patients with complicated urinary tract infection (UTI) and their risk of progressing to urosepsis. Materials and Methods: We conducted a retrospective study including patients diagnosed with UTI hospitalized in the urology department of” Sfântul Apostol Andrei” County Emergency Clinical Hospital (GCH) in Galati, Romania, from September 2019 to May 2022. The inclusion criteria were: UTI proven by urine culture or diagnosed clinically complicated with UTO, fever or shaking chills, and purulent collections, such as psoas abscess, Fournier Syndrome, renal abscess, and paraurethral abscess, showing SIRS. The exclusion criteria were: patients age < 18 years, pregnancy, history of kidney transplantation, hemodialysis or peritoneal dialysis, and patients with missing data. We used the Sequential (Sepsis-Related) Organ Failure Assessment (SOFA) and qSOFA (quick SOFA) scores, and procalcitonin (PCT) to describe the clinical status of the patients. The Charlson Comorbidity Index (CCI) was used to assesses pre-existing morbidities. The hospitalization days and costs and the days of intensive care were considered. Depending on the diagnosis at admission, we divided the patients into three groups: SIRS, sepsis and septic shock. The fourth group was represented by patients who died during hospitalization. Results: A total of 174 patients with complicated UTIs were enrolled in this study. From this total, 46 were enrolled in the SIRS group, 88 in the urosepsis group, and 40 in the septic shock group. A total of 23 patients died during hospitalization and were enrolled in the deceased group. An upward trend of age along with worsening symptoms was highlighted with an average of 56.86 years in the case of SIRS, 60.37 years in the sepsis group, 69.03 years in the septic shock, and 71.04 years in the case of deceased patients (p < 0.04). A statistically significant association between PCT and complex scores (SOFA, CCI and qSOFA) with the evolution of urosepsis was highlighted. Increased hospitalization costs can be observed in the case of deceased patients and those with septic shock and statistically significantly lower in the case of those with SIRS. The predictability of discriminating urosepsis stages was assessed by using the area under the ROC curve (AUC) and very good specificity and sensitivity was identified in predicting the risk of death for PCT (69.57%, 77.33%), the SOFA (91.33%, 76.82%), qSOFA (91.30%, 74.17%) scores, and CCI (65.22%, 88.74%). The AUC value was best for qSOFA (90.3%). For the SIRS group, the PCT (specificity 91.30%, sensitivity 85.71%) and SOFA (specificity 84.78%, sensitivity 78.74%), qSOFA scores (specificity 84.78%, sensitivity 76, 34%) proved to be relevant in establishing the diagnosis. In the case of the septic shock group, the qSOFA (specificity 92.5%, sensitivity 82.71%) and SOFA (specificity 97.5%, sensitivity 77.44%) as well as PCT (specificity 80%, sensitivity 85.61%) are statistically significant disease-defining variables. An important deficit in the tools needed to classify patients into the sepsis group is obvious. All the variables have an increased specificity but a low sensitivity. This translates into a risk of a false negative diagnosis. Conclusions: Although SOFA and qSOFA scores adequately describe patients with septic shock and they are independent prognostic predictors of mortality, they fail to be accurate in diagnosing sepsis. These scores should not replace the conventional triage protocol. In our study, PCT proved to be a disease-defining marker and an independent prognostic predictor of mortality. Patients with important comorbidities, CCI greater than 10, should be treated more aggressively because of increased mortality.

Comprehensive Investigations of Multiple Factors That Are Related to Refractory Outcome in Urosepsis Patients

Background

Urosepsis is an acute life-threating disease, and some cases show refractory outcome to therapy. In an aging society of developed countries, characteristics of urosepsis are becoming complicated. We performed a comprehensive investigation regarding the clinical and social aspects that are related to refractory outcomes in urosepsis patients.

Methods

The patient cohort consisted of 66 patients with urosepsis. Multiple factors from clinical and social aspects were reviewed retrospectively. Two categories of refractory outcomes were defined. One was afebrile resistance (AR); fever continued more than 7 days from the initiation of therapy. Another was discharge resistance (DR); hospitalization continued for more than 30 days. Logistic regression analyses were performed to identify significant factors that are related to the AR or DR.

Results

Univariate analysis demonstrated that high score of Eastern Cooperative Oncology Group Performance Status (ECOG PS) (≥ 2) and Age-adjusted Charlson comorbidity index (CCI) (≥ 4), high serum C-reactive protein (CRP) level (≥ 14.9 mg/dL), and low serum albumin level (≤ 2.26 g/dL) were significantly related to AR. Univariate analysis results also revealed that high score of ECOG PS (≥ 2), high serum creatinine level (≥ 1.54 mg/dL) and vasopressor administration were significantly related to DR. Multivariate analyses demonstrated that low serum albumin level (≤ 2.26g/dL) was the only significant factor that was related to AR. In contrast, high score of ECOG PS (≥ 2) and high serum creatinine level (≥ 1.54 mg/dL) were significant factors that were related to DR.

Conclusion

It is suggested that evaluating serum albumin levels is essential for the therapeutic first step because hypoalbuminemia was the significant factor that was related to obstruction to antipyresis. It is also suggested that the deterioration of patients' activities of daily living and renal dysfunction might be the refractory factors for discharge from the hospital, which was the ultimate therapeutic goal.

Effects of Inappropriate Administration of Empirical Antibiotics on Mortality in Adults With Bacteraemia: Systematic Review and Meta-Analysis

Introduction

Bloodstream infections are associated with high mortality rates and contribute substantially to healthcare costs, but a consensus on the prognostic benefits of appropriate empirical antimicrobial therapy (EAT) for bacteraemia is lacking.

Methods

We performed a systematic search of the PubMed, Cochrane Library, and Embase databases through July 2021. Studies comparing the mortality rates of patients receiving appropriate and inappropriate EAT were considered eligible. The quality of the included studies was assessed using Joanna Briggs Institute checklists.

Results

We ultimately assessed 198 studies of 89,962 total patients. The pooled odds ratio (OR) for the prognostic impacts of inappropriate EAT was 2.06 (P < 0.001), and the funnel plot was symmetrically distributed. Among subgroups without between-study heterogeneity (I² = 0%), those of patients with severe sepsis and septic shock (OR, 2.14), Pitt bacteraemia scores of ≥4 (OR, 1.88), cirrhosis (OR, 2.56), older age (OR, 1.78), and community-onset/acquired Enterobacteriaceae bacteraemia infection (OR, 2.53) indicated a significant effect of inappropriate EAT on mortality. The pooled adjusted OR of 125 studies using multivariable analyses for the effects of inappropriate EAT on mortality was 2.02 (P < 0.001), and the subgroups with low heterogeneity (I² < 25%) exhibiting significant effects of inappropriate EAT were those of patients with vascular catheter infections (adjusted OR, 2.40), pneumonia (adjusted OR, 2.72), or Enterobacteriaceae bacteraemia (adjusted OR, 4.35). Notably, the pooled univariable and multivariable analyses were consistent in revealing the negligible impacts of inappropriate EAT on the subgroups of patients with urinary tract infections and Enterobacter bacteraemia.

Conclusion

Although the current evidence is insufficient to demonstrate the benefits of prompt EAT in specific bacteraemic populations, we indicated that inappropriate EAT is associated with unfavorable mortality outcomes overall and in numerous subgroups. Prospective studies designed to test these specific populations are needed to ensure reliable conclusions.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42021270274.

Rapid Bacterial Detection in Urine Using Laser Scattering and Deep Learning Analysis

Images of laser scattering patterns generated by bacteria in urine are promising resources for deep learning. However, floating bacteria in urine produce dynamic scattering patterns and require deep learning of spatial and temporal features. We hypothesized that bacteria with variable bacterial densities and different Gram staining reactions would generate different speckle images. After deep learning of speckle patterns generated by various densities of bacteria in artificial urine, we validated the model in an independent set of clinical urine samples in a tertiary hospital. Even at a low bacterial density cutoff (1,000 CFU/mL), the model achieved a predictive accuracy of 90.9% for positive urine culture. At a cutoff of 50,000 CFU/mL, it showed a better accuracy of 98.5%. The model achieved satisfactory accuracy at both cutoff levels for predicting the Gram staining reaction. Considering only 30 min of analysis, our method appears as a new screening tool for predicting the presence of bacteria before urine culture. IMPORTANCE This study performed deep learning of multiple laser scattering patterns by the bacteria in urine to predict positive urine culture. Conventional urine analyzers have limited performance in identifying bacteria in urine. This novel method showed a satisfactory accuracy taking only 30 min of analysis without conventional urine culture. It was also developed to predict the Gram staining reaction of the bacteria. It can be used as a standalone screening tool for urinary tract infection.

Utilization of Blood Culture in South Asia for the Diagnosis and Treatment of Febrile Illness

BACKGROUND

Blood culture is the current standard for diagnosing bacteremic illnesses, yet it is not clear how physicians in many low- and middle-income countries utilize blood culture for diagnostic purposes and to inform treatment decisions.

METHODS

We screened suspected enteric fever cases from 6 hospitals in Bangladesh, Nepal, and Pakistan, and enrolled patients if blood culture was prescribed by the treating physician. We used generalized additive regression models to analyze the probability of receiving blood culture by age, and linear regression models to analyze changes by month to the proportion of febrile cases prescribed a blood culture compared with the burden of febrile illness, stratified by hospital. We used logistic regression to analyze predictors for receiving antibiotics empirically. We descriptively reviewed changes in antibiotic therapy by susceptibility patterns and coverage, stratified by country.

RESULTS

We screened 30 809 outpatients resulting in 1819 enteric fever cases; 1935 additional cases were enrolled from other hospital locations. Younger outpatients were less likely to receive a blood culture. The association between the number of febrile outpatients and the proportion prescribed blood culture varied by hospital. Antibiotics prescribed empirically were associated with severity and provisional diagnoses, but 31% (1147/3754) of enteric fever cases were not covered by initial therapy; this was highest in Pakistan (50%) as many isolates were resistant to cephalosporins, which were commonly prescribed empirically.

CONCLUSIONS

Understanding hospital-level communication between laboratories and physicians may improve patient care and timeliness of appropriate antibiotics, which is important considering the rise of antimicrobial resistance.

Impact of antimicrobial de-escalation on mortality: a literature review of study methodology and recommendations for observational studies

Introduction: The safety of de-escalation of empirical antimicrobial therapy is largely based on observational data, with many reporting protective effects on mortality. As there is no plausible biological explanation for this phenomenon, it is most probably caused by confounding by indication.Areas covered: We evaluate the methodology used in observational studies on the effects of de-escalation of antimicrobial therapy on mortality. We extended the search for a recent systematic review and identified 52 observational studies. The heterogeneity in study populations was large. Only 19 (36.5%) studies adjusted for confounders and four (8%) adjusted for clinical stability during admission, all as a fixed variable. All studies had methodological limitations, most importantly the lack of adjustment for clinical stability, causing bias toward a protective effect.Expert opinion: The methodology used in studies evaluating the effects of de-escalation on mortality requires improvement. We depicted all potential confounders in a directed acyclic graph to illustrate all associations between exposure (de-escalation) and outcome (mortality). Clinical stability is an important confounder in this association and should be modeled as a time-varying variable. We recommend to include de-escalation as time-varying exposure and use inverse-probability-of-treatment weighted marginal structural models to properly adjust for time-varying confounders.

Combination of Coral UTI ScreenTM system, gram-stain and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for diagnosis of urinary tract infections directly from urine samples

This study proposes an algorithm for microbiological diagnosis of urinary tract infections based on screening by luminometry and Gram-stain, followed by identification by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Positive urine samples detected with the luminometry screening Coral UTI Screen^TM system underwent Gram staining and identification of the causative organism was performed by MALDI-TOF Microflex LT mass spectrometer (Bruker Daltonics, Germany). Subsequently, the results were compared with those of conventional culture identification using WIDER MIC/id system (Francisco Soria Melguizo SA, Spain). Considering the conventional approach as the gold standard, the proposed algorithm presented both a high specificity (98.1%) and a positive likelihood ratio of 37.42. The implementation of this algorithm would allow diagnosis of urinary tract infection in less than an hour in 92.4% of positive samples. This combination of techniques would be useful particularly for patients with severe UTI, pyelonephritis or urinary sepsis.

Empirical Antibiotic Treatment Does Not Improve Outcomes in Catheter-Associated Urinary Tract Infection: Prospective Cohort Study

Background

Catheter associated urinary tract infection (CAUTI) is the most common healthcare-associated acquired infection. We aimed to describe the short- and long-term survival of patients with CAUTI and the impact of the empirical antibiotic treatment on survival rates.

Methods

In this prospective observational study we included consecutive adult patients with a chronic indwelling catheter-associated UTI and sepsis hospitalized in medical departments. The primary outcomes were 30-days all-cause mortality and long-term survival at end of the follow-up. A multivariate analysis using logistic regression and Cox proportional hazard model was performed to identify independent risk factors for an adverse outcome. A propensity-score model for receiving appropriate empirical antibiotic therapy was constructed and used to match patients.

Results

Overall, 315 consecutive patients with CAUTI were enrolled. The cohort consisted of elderly to very old patients (mean age 79.2 ± 11.5). The crude 30-day all-cause mortality rate was 30.8% (97/315). The median survival time was 82 days (interquartile range [IQR] 22-638). Appropriate early empirical treatment had no statistically significant association with 30-day mortality, propensity score-matched odds ratio (OR) 1.39 (0.76-2.55). Similarly, in the propensity-matched cohort, appropriate empirical treatment was not statistically associated with long-term survival (hazard ratio [HR] = 0.99, 95% confidence interval [CI] 0.75-1.3).

Conclusions

In our setting, patients with CAUTI had poor short- and long-term prognosis regardless of appropriate empirical antibiotic treatment. Avoiding empirical antibiotics for CAUTI might be an important antibiotic stewardship intervention in hospitals.

Prevention and management of urosepsis triggered by ureteroscopy

Urosepsis is a potentially life-threatening phenomenon that may occur after an ureteroscopic procedure. With the increasingly widespread adoption of ureteroscopy, there is a concern that the rates of urosepsis may increase. This review examines the current work being undertaken to minimize postprocedure infections both in the field of device development and in clinical care. Guidelines for the diagnosis and management of urosepsis will be discussed.

Inappropriate Empirical Treatment of Uncomplicated Cystitis in Thai Women: Lessons Learned

A prospective study conducted in a Thai general practice clinic demonstrated a high prevalence (91.3%) of inappropriate empirical antibiotic use in women with uncomplicated cystitis and 42.6% Escherichia coli fluoroquinolone resistance. An annual update of antimicrobial resistance surveillance data of uropathogens may permit targeted treatment of patients in hospital care.

Spectrum and antibiotic resistance of uropathogens between 2004 and 2015 in a tertiary care hospital in Hungary

PURPOSE

Surveillance of the bacterial spectrum and antibiotic-resistance patterns of locally occurring uropathogens is essential to serve as a basis for empirical treatment of urinary tract infections (UTIs), as antibiotic-resistance rates may vary geographically with significant differences between countries and regions, and with time.

METHODOLOGY

We retrospectively analysed all urine samples taken in the department of urology in a tertiary care hospital in Hungary from January 2004 to December 2015.Results/Key findings. The five most commonly occurring bacteria were Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus mirabilis. Resistance of Escherichia coli to ciprofloxacin increased significantly from 19 to 25 %. Although the resistance of Escherichia coli against cephalosporins showed an increasing trend, it still remained generally low. However, resistance rates of K. pneumoniae to cephalosporins were very high, reaching 60 %, due to the high rate of extended-spectrum-β-lactamase-positive Klebsiella strains. We observed a significant increase in the rate of carbapenem-resistant Pseudomonas aeruginosa.

CONCLUSION

Fluoroquinolones cannot be recommended for empirical treatment in our region. Cephalosporins can be a good empirical choice for treating Gram-negative UTIs, but should be avoided when multi-drug resistant (MDR) bacteria are suspected. Increases in the rate of carbapenem-resistant Pseudomonas aeruginosa, and in the general rate of MDR bacteria, are both a very alarming trend. We recommend practising prudent antibiotic policy, preferably using antibiotics with the narrowest possible spectrum.

Urosepsis: Overview of the Diagnostic and Treatment Challenges

Urosepsis is defined as sepsis caused by an infection in the urogenital tract. In approximately 30% of all septic patients the infectious focus is localized in the urogenital tract, mainly due to obstructions at various levels, such as ureteral stones. Urosepsis may also occur after operations in the urogenital tract. In urosepsis, complete bacteria and components of the bacterial cell wall from the urogenital tract trigger the host inflammatory event and act as exogenous pyrogens on eukaryotic target cells of patients. A burst of second messenger molecules leads to several different stages of the septic process, from hyperactivity to immunosuppression. As pyelonephritis is the most frequent cause for urosepsis, the kidney function is therefore most important in terms of cause and as a target organ for dysfunction in the course of the sepsis.Since effective antimicrobial therapy must be initiated early during sepsis, the empiric intravenous therapy should be initiated immediately after microbiological sampling. For the selection of appropriate antimicrobials, it is important to know risk factors for resistant organisms and whether the sepsis is primary or secondary and community or nosocomially acquired. In addition, the preceding antimicrobial therapies should be recorded as precisely as possible. Resistance surveillance should, in any case, be performed locally to adjust for the best suitable empiric treatment. Treatment challenges arise from the rapid increase of antibiotic resistance in Gram-negative bacteria, especially extended-spectrum β-lactamase (ESBL)-producing bacteria. Treatment of urosepsis comprises four basic strategies I) supportive therapy (stabilizing and maintaining blood pressure), II) antimicrobial therapy, III) control or elimination of the complicating factor, and IV) specific sepsis therapy.

Ceftazidime-avibactam Versus Doripenem for the Treatment of Complicated Urinary Tract Infections, Including Acute Pyelonephritis: RECAPTURE, a Phase 3 Randomized Trial Program

BACKGROUND

The global emergence of carbapenem-resistant Enterobacteriaceae highlights the urgent need to reduce carbapenem dependence. The phase 3 RECAPTURE program compared the efficacy and safety of ceftazidime-avibactam and doripenem in patients with complicated urinary tract infection (cUTI), including acute pyelonephritis.

METHODS

Hospitalized adults with suspected or microbiologically confirmed cUTI/acute pyelonephritis were randomized 1:1 to ceftazidime-avibactam 2000 mg/500 mg every 8 hours or doripenem 500 mg every 8 hours (doses adjusted for renal function), with possible oral antibiotic switch after ≥5 days (total treatment duration up to 10 days or 14 days for patients with bacteremia).

RESULTS

Of 1033 randomized patients, 393 and 417 treated with ceftazidime-avibactam and doripenem, respectively, were eligible for the primary efficacy analyses; 19.6% had ceftazidime-nonsusceptible baseline pathogens. Noninferiority of ceftazidime-avibactam vs doripenem was demonstrated for the US Food and Drug Administration co-primary endpoints of (1) patient-reported symptomatic resolution at day 5: 276 of 393 (70.2%) vs 276 of 417 (66.2%) patients (difference, 4.0% [95% confidence interval {CI}, -2.39% to 10.42%]); and (2) combined symptomatic resolution/microbiological eradication at test of cure (TOC): 280 of 393 (71.2%) vs 269 of 417 (64.5%) patients (difference, 6.7% [95% CI, .30% to 13.12%]). Microbiological eradication at TOC (European Medicines Agency primary endpoint) occurred in 304 of 393 (77.4%) ceftazidime-avibactam vs 296 of 417 (71.0%) doripenem patients (difference, 6.4% [95% CI, .33% to 12.36%]), demonstrating superiority at the 5% significance level. Both treatments showed similar efficacy against ceftazidime-nonsusceptible pathogens. Ceftazidime-avibactam had a safety profile consistent with that of ceftazidime alone.

CONCLUSIONS

Ceftazidime-avibactam was highly effective for the empiric treatment of cUTI (including acute pyelonephritis), and may offer an alternative to carbapenems in this setting.

CLINICAL TRIALS REGISTRATION

NCT01595438; NCT01599806.

National Survey of Thai Infectious Disease Physicians on Treatment of Carbapenem-Resistant Acinetobacter baumannii Ventilator-Associated Pneumonia: The Role of Infection Control Awareness

OBJECTIVE To evaluate the expected and treatment outcomes of Thai infectious disease physicians (IDPs) regarding carbapenem-resistant Acinetobacter baumannii (CRAB) ventilator-associated pneumonia (VAP) METHODS From June 1, 2014, to March 1, 2015, survey data regarding the expected and clinical success rates of CRAB VAP treatment were collected from all Thai IDPs. The expected success rate was defined as the expectation of clinical response after CRAB VAP treatment for the given case scenario. Clinical success rate was defined as the overall reported success rate of CRAB VAP treatment based on the clinical practice of each IDP. The expected and clinical success rates were divided into low (80%) categories and were then compared with standard clinical response rates archived in the existing literature. RESULTS Of 183 total Thai IDPs, 111 (60%) were enrolled in this study. The median expected and clinical success rates were 68% and 58%, respectively. Using multivariate analysis, we determined that working in a hospital that implemented the standard intervention combined with an intensified infection control (IC) intervention for CRAB (adjusted odds ratio [aOR], 3.01; 95% confidence interval [CI], 1.17-7.73; P=.02) was associated with standard and high expected rates (>60%). Being a board-certified IDP (aOR, 5.76; 95% CI, 2.16-15.37; P60%). We identified a significant correlation between expected and clinical success rates (r=0.58; P<.001). CONCLUSIONS Awareness of IC among IDPs can improve physicians' expected and clinical success rates for CRAB VAP treatment, and treatment experience impacts overall treatment success. Infect. Control Hosp. Epidemiol. 2015;37(1):61-69.

Lower antibiotic costs attributable to clinical microbiology rounds

OBJECTIVE

At our institution, our microbiologist, pharmacist, and infectious disease (ID) team meet to discuss ID patients, and this meeting is referred to as microbiology rounds. We hypothesized that our microbiology rounds reduce antibiotic costs. The study involved a review of 80 patients with an ID consultation order at each of the 3 hospitals: hospital A (HA) (only HA has microbiology rounds), hospital B (HB), and hospital C (HC). Of this population, we included patients with a positive blood culture. Thirty-six patients who met the above criteria were included in the study. The average antibiotic cost/patient/day at HA, HB, and HC were $66.0, $123, and $109, respectively. Also, we found that change in antibiotics was appropriate when compared to the final microbiology results in 90%, 44%, and 40% of the time at HA, HB, and HC, respectively. Herein, we found an association between conducting microbiology rounds and reduction of antibiotic cost.

New procedure for rapid identification of microorganisms causing urinary tract infection from urine samples by mass spectrometry (MALDI-TOF)

INTRODUCTION

Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry is widely established as a technique in clinical microbiology laboratories for the identification of microorganisms. Using this technique, it is also possible to obtain the identification of microorganisms from untreated urine samples.

METHODS

In this study, a differential centrifugation protocol and a criterion for validation of the results in order to achieve microbial identification from untreated urine samples are proposed. Additionally, the sensitivity of the analytical procedure in monobacterial urine samples has been evaluated.

RESULTS

A 90% sensitivity (confidence interval of 81.96%-94.84%) was obtained in urine samples with bacterial counts of ≥1×10(5)CFU/ml, and it was possible to improve the percentages of direct identifications from urine samples with bacterial counts of <1×10(5)CFU/ml.

CONCLUSION

It is concluded that the MALDI-TOF system is both fast and reliable in the identification of individual microorganisms from untreated urine samples with counts of ≥1×10(5)CFU/ml.

Reducing infection rates after prostate biopsy

Over the years, prostate biopsy has become the gold-standard technique for diagnosing prostate carcinoma. Worldwide, several million prostate biopsies are performed every year, most commonly using the transrectal approach. Preoperative antibiotic prophylaxis with fluoroquinolones has been shown to be effective for reducing infection rates. However, in recent years, an increase in febrile infection rates after transrectal prostate biopsy (from 1% to 4%) has been reported in retrospective and prospective studies. The predominant risk factor for infection seems to be the presence of fluoroquinolone-resistant bacteria in faeces. Patients at risk of fluoroquinolone resistance should receive carefully selected antibiotics at sufficient concentrations to be effective. Targeted prophylaxis after rectal flora swabbing has been shown to be efficacious compared with empirical antibiotic prophylaxis. Several forms of bowel preparations are under investigation, although none have yet been shown to significantly reduce infection rates. Perineal prostate biopsy is currently being evaluated as a strategy for preventing the inoculation of rectal flora, but limited data support this approach at present.

Antibiotic treatment for urinary tract infections: pharmacokinetic/pharmacodynamic principles

Bacterial urinary tract infections (UTIs) frequently occur in the outpatient as well as in the nosocomial setting. The stratification into uncomplicated and complicated UTIs has proven to be clinically useful. Bacterial virulence factors on the one hand, and the integrity of the host defense mechanisms on the other, determine the course of the infection. Late complications or sequelae might ensue if the defense mechanisms are disturbed, either by a genetic or an acquired cause. Escherichia coli is the most prevalent organism in uncomplicated UTIs, whereas the bacterial spectrum is much broader in complicated UTIs, including Gram-negative and -positive, and often multiresistant organisms. Therapy for uncomplicated UTIs is almost exclusively antibacterial, whereas in complicated UTIs the complicating factors need to be treated as well. The success of antibiotic therapy of UTIs in a population can be estimated by four parameters: the minimal inhibitory concentrations of the clinical isolates, the pharmacokinetic and pharmacodynamic profiles, and the protein binding of the treatment drug. In uncomplicated UTIs, antimicrobial therapy is usually empiric, whereas in complicated UTIs antibiotic therapy should be more individualized; tailored to the individual patient.

An alternate pathophysiologic paradigm of sepsis and septic shock: implications for optimizing antimicrobial therapy

The advent of modern antimicrobial therapy following the discovery of penicillin during the 1940s yielded remarkable improvements in case fatality rate of serious infections including septic shock. Since then, pathogens have continuously evolved under selective antimicrobial pressure resulting in a lack of significant improvement in clinical effectiveness in the antimicrobial therapy of septic shock despite ever more broad-spectrum and potent drugs. In addition, although substantial effort and money has been expended on the development novel non-antimicrobial therapies of sepsis in the past 30 years, clinical progress in this regard has been limited. This review explores the possibility that the current pathophysiologic paradigm of septic shock fails to appropriately consider the primacy of the microbial burden of infection as the primary driver of septic organ dysfunction. An alternate paradigm is offered that suggests that has substantial implications for optimizing antimicrobial therapy in septic shock. This model of disease progression suggests the key to significant improvement in the outcome of septic shock may lie, in great part, with improvements in delivery of existing antimicrobials and other anti-infectious strategies. Recognition of the role of delays in administration of antimicrobial therapy in the poor outcomes of septic shock is central to this effort. However, therapeutic strategies that improve the degree of antimicrobial cidality likely also have a crucial role.

Resistance patterns of nosocomial urinary tract infections in urology departments: 8-year results of the global prevalence of infections in urology study

OBJECTIVE

To present the worldwide antibiotic resistance rates of uropathogens reported in nosocomial urinary tract infections (NAUTI) during the period of 2003-2010.

MATERIALS AND METHODS

Data from the Global Prevalence Study of Infections in Urology from the period of 2003-2010 were analyzed to evaluate the resistance rates of pathogens causing NAUTI. The web-based application was used to record data of investigators from urology departments participating in the study every year during the days allocated in November. Each center was allowed to enter data on a single day of the study. The point prevalence data was used to find differences among geographic regions and years by utilizing multiple logistic regression analysis.

RESULTS

A total of 19,756 patients were hospitalized during the study period, and in 1,866 of them, NAUTI was reported. Proof of infection was reported in 1,395 patients. Resistance rates of all antibiotics tested other than imipenem against the total bacterial spectrum were higher than 10 % in all regions. Resistance to almost all pathogens was lowest in North Europe, and there is no single year where an outbreak of resistance has been detected.

CONCLUSION

The resistance rates of most of the uropathogens against the antibiotics tested did not show significant trends of increase or decrease with Asia exhibiting the highest rates in general. The only antibiotic tested with an overall resistance rate below 10 % was imipenem. Knowledge of regional and local resistance data and prudent use of antibiotics are necessary to optimize antibiotic therapy in urological patients with NAUTI.

Antibiotic prescriptions in critically-ill patients: a latin american experience

BACKGROUND

It is widely acknowledged that the presence of infection is an important outcome determinant for intensive care unit (ICU) patients. In fact, antibiotics are one of the most common therapies administered in the ICU settings.

AIM

To evaluate the current usage of antibiotics in Latin American ICUs.

SUBJECTS AND METHODS

A one-day p-oint prevalence study to investigate the patterns of antibiotic was undertaken in 72 Latin American (LA) ICUs. Data was analyzed using the Statistix 8 statistical software, version 2.0 (USA). Results were expressed as proportions. When applicable, two tailed hypothesis testing for difference in proportions was used (Proportion Test); a P value of <0.05 was considered significant.

RESULTS

Of 704 patients admitted, 359 received antibiotic treatment on the day of the study (51%), of which 167/359 cases (46.5%) were due to hospital-acquired infections. The most frequent infection reorted was nosocomial pneumonia (74/359, 21%). Only in 264/359 patients (73.5%), cultures before starting antibiotic treatment were performed. Thirty-eight percent of the isolated microorganisms were Enterobacteriaceae extended-spectrum β-lactamase-producing, 11% methicillin-resistant Staphylococcus aureus and 10% carbapenems-resistant non-fermentative Gram-negatives. The antibiotics most frequently prescribed were carbapenems (125/359, 35%), alone or in combination with vancomycin or other antibiotic. There were no significant differences in the "restricted" antibiotic prescription (carbapenems, vancomycin, piperacillin-tazobactam, broad-spectrum cephalosporins, fluoroquinolones, tigecycline and linezolid) between patients with APACHE II score at the beginning of the antibiotic treatment <15 [83/114 (72.5%)] and ≥15 [179/245 (73%)] (P = 0.96). Only 29% of the antibiotic treatments were cultured directed (104/359).

CONCLUSION

Carbapenems (alone or in combination) were the most frequently prescribed antibiotics in LA ICUs. However, the problem of carbapenem resistance in LA requires that physicians improve the use of this class of antibiotics. Our findings show that our web-based method for collection of one-day point prevalence was implemented successfully. However, based on the limitations of the model used, the results of this study must be taken with caution.

Diagnosis and management for urosepsis

Urosepsis is defined as sepsis caused by a urogenital tract infection. Urosepsis in adults comprises approximately 25% of all sepsis cases, and is in most cases due to complicated urinary tract infections. The urinary tract is the infection site of severe sepsis or septic shock in approximately 10-30% of cases. Severe sepsis and septic shock is a critical situation, with a reported mortality rate nowadays still ranging from 30% to 40%. Urosepsis is mainly a result of obstructed uropathy of the upper urinary tract, with ureterolithiasis being the most common cause. The complex pathogenesis of sepsis is initiated when pathogen or damage-associated molecular patterns recognized by pattern recognition receptors of the host innate immune system generate pro-inflammatory cytokines. A transition from the innate to the adaptive immune system follows until a T(H2) anti-inflammatory response takes over, leading to immunosuppression. Treatment of urosepsis comprises four major aspects: (i) early diagnosis; (ii) early goal-directed therapy including optimal pharmacodynamic exposure to antimicrobials both in the plasma and in the urinary tract; (iii) identification and control of the complicating factor in the urinary tract; and (iv) specific sepsis therapy. Early adequate tissue oxygenation, adequate initial antibiotic therapy, and rapid identification and control of the septic focus in the urinary tract are critical steps in the successful management of a patient with urosepsis, which includes early imaging, and an optimal interdisciplinary approach encompassing emergency unit, urological and intensive-care medicine specialists.

Effect of pravastatin and fosinopril on recurrent urinary tract infections

OBJECTIVES

Recurrent urinary tract infections (UTIs) are a problem affecting both women and men. Animal experiments and in vitro studies indicate that statins might prevent recurrent UTIs. We assessed the effects of pravastatin on UTI antibiotic prescribing among adults.

METHODS

A post hoc analysis was conducted with data from PREVEND IT, a trial among participants randomized to receive pravastatin, fosinopril or placebo in a 2 × 2 factorial design over 4 years. Trial data were linked to the pharmacy prescription database IADB.nl. The primary outcome was the number of prescriptions with a nitrofuran derivate, a sulphonamide or trimethoprim as a proxy for UTI antibiotic prescribing. Generalized estimating equations were used to estimate the effect on the number of UTI antibiotic prescriptions. Cox regression was used to determine the effect on first and second (recurrent) UTI antibiotic prescriptions.

RESULTS

Of the 864 trial participants, 655 were eligible for analysis. During an average follow-up of 3.8 years, 112 (17%) participants received at least one UTI antibiotic prescription. Intention-to-treat analyses showed that pravastatin was associated with a reduced total number of UTI antibiotic prescriptions (relative risk, 0.43; 95% CI, 0.21-0.88) and occurrence of second UTI antibiotic prescriptions [hazard ratio (HR), 0.25; 95% CI, 0.08-0.77]. No significant effect on occurrence of first UTI antibiotic prescriptions was found (HR, 0.83; 95% CI, 0.57-1.20). Fosinopril was associated with an increased occurrence of first UTI antibiotic prescriptions (HR, 1.82; 95% CI, 1.16-2.88). Combination therapy with fosinopril and pravastatin did not significantly influence the number of UTI antibiotic prescriptions.

CONCLUSIONS

This study suggests that pravastatin can reduce the occurrence of recurrent UTIs. Larger studies among patients with recurrent UTIs are warranted.

Evaluation of the use of piperacillin/tazobactam (Tazocin) at Hamad General Hospital, Qatar: are there unjustified prescriptions?

Objectives

The aim of this study was to evaluate the appropriateness of piperacillin/tazobactam (Tazocin^®; Pfizer, New York, NY) usage in our hospital.

Subjects and methods

This retrospective study was designed to involve all patients admitted to Hamad General Hospital and prescribed piperacillin/tazobactam as an empiric therapy from January 1 to March 31, 2008. The medical records of such patients were retrospectively reviewed and studied.

Results

During this period, 610 prescriptions were ordered for 596 patients. The main indication for initiation of Tazocin was sepsis (207/610; 34%). The overall rate of appropriateness of empirical therapy was 348/610 (57%). Most of the inappropriate prescriptions were in cases of aspiration pneumonia and abdominal infections, with inappropriate prescriptions found mostly in surgical wards (86%) and the surgical intensive care unit (66.7%). Septic work-up results showed positive cultures in 57% (345/610) of cases. There were 198/254 prescriptions (78%) where antibiotics were changed according to the sensitivity data to narrow-spectrum antimicrobials. In 56/254 (22%) cases, pathogens were susceptible to narrow-spectrum antibiotics even though piperacillin/tazobactam was continued.

Conclusion

Our study showed that there was an injudicious use of piperacillin/tazobactam at our hospital, evidenced by the significant number of inappropriate empiric prescriptions and inappropriate drug modifications, based on the results of microbial cultures and antibiograms.

Urosepsis--from the view of the urologist

Urosepsis accounts for approximately 25% of all sepsis cases and may develop from a community-or nosocomial-acquired urinary tract infection (UTI). The underlying UTI is almost exclusively a complicated one with involvement of parenchymatous urogenital organs (e.g. kidneys, prostate). In urosepsis, as in other types of sepsis, the severity of sepsis depends mostly upon the host response. The urological management of urosepsis comprises early diagnosis, early fluid and oxygen treatment, early antibiotic therapy and early control of the complicating factor in the urinary tract. Time from admission to therapy is critical. The shorter the time to effective treatment, the higher is the success rate. This aspect has to become incorporated into the organisational process, including urologists, radiologists and intensive care specialists amongst others. Adequate initial antibiotic therapy has to be insured. This goal implies, however, a wide array of measures over time to ensure a rational antibiotic policy, including microbiologists and clinical pharmacologists. Dosage of an antibiotic in the septic patient generally has to be high to ensure adequate pharmacological exposure in the individual patient.

Approach to a patient with urosepsis

Urinary tract infections can occur in all age groups and produce an exceptionally broad range of clinical syndromes ranging from asymptomatic bacteriuria to acute pyelonephritis with Gram negative sepsis to septic shock. In approximately one-quarter of all patients with sepsis, the focus of infection is localized to the urogenital tract. This may lead to substantial morbidity and significant economic implications. We present a review of the current approaches to managing urospesis.

Association between the number of blood cultures and appropriateness of care for suspected bacteremic urinary tract infection in the elderly

The objective of this study was to evaluate the association between the number of blood cultures collected and the appropriateness of care for suspected bacteremic community-acquired urinary tract infection (UTI) in the elderly. We retrospectively evaluated the medical records of 129 patients with UTI > 65 years old admitted to a large community-based training hospital in Japan from 1 January 2006 to 31 December 2009. We assessed the association between the number of blood cultures collected and the appropriateness of care received, as well as other factors. Two-thirds of the patients were women, and patients > 85 years old accounted for 45.0% of the cases. Most of the organisms isolated from the urine and blood were Escherichia coli (65.4-67.0%). More than two blood cultures were collected 79.1% of the time, and 66.7% of the cases were evaluated as having been treated appropriately. The appropriateness of care was not significantly related to the number of blood cultures. The appropriateness of care received in the general internal medicine department was significantly higher (p = 0.016) than that in other departments. Thus, the appropriateness of care for suspected bacteremic UTI in the elderly was not significantly associated with the number of blood cultures. However, the department of hospitalization may have influenced the appropriateness of care.

Rapid qualitative urinary tract infection pathogen identification by SeptiFast real-time PCR

BACKGROUND

Urinary tract infections (UTI) are frequent in outpatients. Fast pathogen identification is mandatory for shortening the time of discomfort and preventing serious complications. Urine culture needs up to 48 hours until pathogen identification. Consequently, the initial antibiotic regimen is empirical.

AIM

To evaluate the feasibility of qualitative urine pathogen identification by a commercially available real-time PCR blood pathogen test (SeptiFast®) and to compare the results with dipslide and microbiological culture.

DESIGN OF STUDY

Pilot study with prospectively collected urine samples.

SETTING

University hospital.

METHODS

82 prospectively collected urine samples from 81 patients with suspected UTI were included. Dipslide urine culture was followed by microbiological pathogen identification in dipslide positive samples. In parallel, qualitative DNA based pathogen identification (SeptiFast®) was performed in all samples.

RESULTS

61 samples were SeptiFast® positive, whereas 67 samples were dipslide culture positive. The inter-methodological concordance of positive and negative findings in the gram+, gram- and fungi sector was 371/410 (90%), 477/492 (97%) and 238/246 (97%), respectively. Sensitivity and specificity of the SeptiFast® test for the detection of an infection was 0.82 and 0.60, respectively. SeptiFast® pathogen identifications were available at least 43 hours prior to culture results.

CONCLUSION

The SeptiFast® platform identified bacterial DNA in urine specimens considerably faster compared to conventional culture. For UTI diagnosis sensitivity and specificity is limited by its present qualitative setup which does not allow pathogen quantification. Future quantitative assays may hold promise for PCR based UTI pathogen identification as a supplementation of conventional culture methods.

Formal adult infectious disease specialist consultations in the outpatient setting at a comprehensive cancer center (1998-2008): diverse and impactful

PURPOSE

The literature on the impact of infectious disease (ID) consulations in the outpatient treatment of cancer is scarce.

METHODS

The medical records of consecutive adult patients with cancer formally evaluated by two board-certified ID specialists in an outpatient setting at our institution over a 10-year period (1998-2008) were reviewed retrospectively. The patients' demographics, referring departments, purposes for consultation, ID specialist recommendations, and overall impact of consultations on outcome were analyzed.

RESULTS

We identified 598 patients who underwent ID specialist consultations. Most of them had solid tumors (53%), predominantly breast cancer, whereas non-Hodgkin's lymphoma was the most common hematologic malignancy. Almost half of the patients (45%) had active malignancies, but few of them were severely neutropenic (8%) or had been receiving high doses of corticosteroids (17%). The most frequent requests for consultation were culture or serologic test (15%), and treatment of cellulitis and/or surgical wound infections (14%). Of 337 isolated pathogens, the most prevalent were methicillin-resistant Staphylococcus aureus (13%) and Pseudomonas aeruginosa (8%), as well as atypical mycobacteria (16%) and Aspergillus species (11%). ID specialists provided alternative diagnoses in 53% of the cases, including identification of a different infection (46%), a noninfectious etiology (29%), colonization (16%), and drug-related toxic effects (9%). Overall, we deemed the contribution of the ID specialist to be significant in 62% of the consultations.

CONCLUSIONS

ID specialists contribute significantly to the outpatient care of individuals with cancer.

[Urosepsis and treatment]

Urosepsis is one of the most frequent sepsis entities. Mortality from urosepsis is nowadays mostly lower than from other entities. Sepsis syndrome is pathophysiologically characterized by a generalized infection and immune dysregulation. Exogenous microbiological and active or passive endogenous factors released from body cells initiate and accompany the immune dysregulation. Diagnosis and therapy of urosepsis need to be instigated as early as possible (within the first hour), in order to prevent cell and tissue damage in the early phase. For this reason a series of measures is started, aimed at achieving early control of the focus of infection, providing antibiotic treatment, and stabilizing respiratory and cardiovascular function in order to optimize tissue oxygenation. A significant clinical problem ensues due to increasing antibiotic resistance mainly of enterobacteria. The choice of antibiotic therefore is made on the basis of local antibiotic resistance statistics. Dosage is determined on an individual basis, as well as according to current pharmacokinetic/pharmacodynamic knowledge. The intensive care of the septic patient needs to be started as early as on patient admission and, where necessary, continued on the intensive care ward.

Bloodstream infections and clinical significance of healthcare-associated bacteremia: a multicenter surveillance study in Korean hospitals

Recent changes in healthcare systems have changed the epidemiologic paradigms in many infectious fields including bloodstream infection (BSI). We compared clinical characteristics of community-acquired (CA), hospital-acquired (HA), and healthcare-associated (HCA) BSI. We performed a prospective nationwide multicenter surveillance study from 9 university hospitals in Korea. Total 1,605 blood isolates were collected from 2006 to 2007, and 1,144 isolates were considered true pathogens. HA-BSI accounted for 48.8%, CA-BSI for 33.2%, and HCA-BSI for 18.0%. HA-BSI and HCA-BSI were more likely to have severe comorbidities. Escherichia coli was the most common isolate in CA-BSI (47.1%) and HCA-BSI (27.2%). In contrast, Staphylococcus aureus (15.2%), coagulase-negative Staphylococcus (15.1%) were the common isolates in HA-BSI. The rate of appropriate empiric antimicrobial therapy was the highest in CA-BSI (89.0%) followed by HCA-BSI (76.4%), and HA-BSI (75.0%). The 30-day mortality rate was the highest in HA-BSI (23.0%) followed by HCA-BSI (18.4%), and CA-BSI (10.2%). High Pitt score and inappropriate empirical antibiotic therapy were the independent risk factors for mortality by multivariate analysis. In conclusion, the present data suggest that clinical features, outcome, and microbiologic features of causative pathogens vary by origin of BSI. Especially, HCA-BSI shows unique clinical characteristics, which should be considered a distinct category for more appropriate antibiotic treatment.

Prescription of antibiotics in intensive care units in Latin America: an observational study

A one-day point prevalence study to investigate the patterns of antibiotic use was undertaken in 43 latin American (LA) intensive care units. Of 510 patients admitted, 231 received antibiotic treatment on the day of the study (45%); in 125 cases (54%) due to nosocomial-acquired infections. The most frequent infection reported was nosocomial pneumonia (43%). Only in 122 patients (53%) were cultures performed before starting antibiotic treatment. 33% of the isolated microorganisms were enterobacteriaceae (40% extended-spectrum beta-lactamase-producing), 23% methicillin-resistant Staphylococcus aureus and 17% carbapenems-resistant non-fermentative Gram-negatives. The antibiotics most frequently prescribed were carbapenems (99/231, 43%); alone (60/99, 60%) or in combination with vancomycin (39/99, 40%). "Restricted" antibiotics (carbapenems, vancomycin, piperacillin-tazobactam, broad-spectrum cephalosporins, tigecycline, polymixins and linezolid) were most frequently indicated in severely ill patients (APACHE II score at admission >15, p=0.0007 and, SOFA score at the beginning of the antibiotic treatment >3, p=0.0000). Only 36% of antibiotic treatments were cultured-directed.Our findings help explain the high rates of multidrug-resistant pathogens in LA settings (i.e. ESBL-producing Gram-negatives) and the severity of the registered patients illnesses.

Impact of reporting gram stain results from blood culture bottles on the selection of antimicrobial agents

We assessed the usefulness of reporting direct blood Gram stain results compared with the results of positive blood cultures in 482 episodes and monitored impact on selection of antimicrobial treatment. We found that the reporting groups "Staphylococcus spp," "Pseudomonas spp and related organisms," and "yeasts" identified in this way matched perfectly with later culture identification. When the report indicated Staphylococcus spp or Pseudomonas spp and related organisms, physicians started or changed antimicrobials suitable for these bacteria more frequently than when "other streptococci" and "family Enterobacteriaceae" were reported (P < .05). Incorrect recognition of Acinetobacter spp as Enterobacteriaceae family is still the most challenging problem in this context. Gram stain results that definitively identify Staphylococcus spp, Pseudomonas spp and related organisms, and yeasts reliably can be rapidly provided by clinical laboratories; this information has a significant impact on early selection of effective antimicrobials. Further investigation is needed to assess the clinical impact of reporting Gram stain results in bacteremia.

Therapeutic challenges of urosepsis

Urosepsis accounts for approximately 25% of all sepsis cases and may develop from a community or nosocomial acquired urinary tract infection (UTI). The underlying UTI is almost exclusively a complicated one with involvement of parenchymatous urogenital organs (e.g. kidneys, prostate). In urosepsis, as in other types of sepsis, the severity of sepsis depends mostly upon the host response. The treatment of urosepsis comprises four major aspects: Early goal directed therapy, early optimal pharmacodynamic exposure to antimicrobials, early control of the complicating factor in the urinary tract and specific sepsis therapy. Following these prerequisites there appear two major challenges that need to be addressed: Firstly, time from admission to therapy is critical; the shorter the time to effective treatment, the higher the success rate. This aspect has to become incorporated into the organisational process. Secondly, adequate initial antibiotic therapy has to be insured. This goal implies however, a wide array of measures to ensure rational antibiotic policy. Both challenges are best targeted if an interdisciplinary approach at any level of the process is established, encompassing urologists, intensive care specialists, radiologists, microbiologists and clinical pharmacologists working tightly together at any time.

Pharmacokinetics/pharmacodynamics of antibacterials in the Intensive Care Unit: setting appropriate dosing regimens

Patients admitted to Intensive Care Units (ICUs) are at very high risk of developing severe nosocomial infections. Consequently, antimicrobials are among the most important and commonly prescribed drugs in the management of these patients. Critically ill patients in ICUs include representatives of all age groups with a range of organ dysfunction related to severe acute illness that may complicate long-term illness. The range of organ dysfunction, together with drug interactions and other therapeutic interventions (e.g. haemodynamically active drugs and continuous renal replacement therapies), may strongly impact on antimicrobial pharmacokinetics in critically ill patients. In the last decade, it has become apparent that the intrinsic pharmacokinetic (PK) and pharmacodynamic (PD) properties are the major determinants of in vivo efficacy of antimicrobial agents. PK/PD parameters are essential in facilitating the translation of microbiological activity into clinical situations, ensuring a successful outcome. In this review, we analyse the typical patterns of antimicrobial activity and the corresponding PK/PD parameters, with a special focus on a PK/PD dosing approach of the antimicrobial agent classes commonly utilised in the ICU setting.