Empirical Antimicrobial Therapy In Patients Research Articles

Clinical Predictors of Bacteremia Outcome After Initial Empirical Antimicrobial Therapy in Patients with Hematological Malignancies: A Retrospective Analysis

Clinical Predictors of Bacteremia Outcome After Initial Empirical Antimicrobial Therapy in Patients with Hematological Malignancies: A Retrospective Analysis

Determinants of Inadequate Empiric Antimicrobial Therapy in ICU Sepsis Patients in Al-Madinah Al-Munawwarah, Saudi Arabia: A Comparison of Artificial Neural Network and Regression Analysis.

In the management of sepsis, providing adequate empiric antimicrobial therapy is one of the most important pillars of sepsis management. Therefore, it is important to evaluate the adequacy of empiric antimicrobial therapy (EAMT) in sepsis patients admitted to intensive care units (ICU) and to identify the determinants of inadequate EAMT. The aim of this study was to evaluate the adequacy of empiric antimicrobial therapy in patients admitted to the ICU with sepsis or septic shock, and the determinants of inadequate EAMT. The data of patients admitted to the ICU units due to sepsis or septic shock in two tertiary healthcare facilities in Al-Madinah Al-Munawwarah were retrospectively reviewed. The current study used logistic regression analysis and artificial neural network (ANN) analysis to identify determinants of inadequate empiric antimicrobial therapy, and evaluated the performance of these two approaches in predicting the inadequacy of EAMT. The findings of this study showed that fifty-three per cent of patients received inadequate EAMT. Determinants for inadequate EAMT were APACHE II score, multidrug-resistance organism (MDRO) infections, surgical history (lower limb amputation), and comorbidity (coronary artery disease). ANN performed as well as or better than logistic regression in predicating inadequate EAMT, as the receiver operating characteristic area under the curve (ROC-AUC) of the ANN model was higher when compared with the logistic regression model (LRM): 0.895 vs. 0.854. In addition, the ANN model performed better than LRM in predicting inadequate EAMT in terms of classification accuracy. In addition, ANN analysis revealed that the most important determinants of EAMT adequacy were the APACHE II score and MDRO. In conclusion, more than half of the patients received inadequate EAMT. Determinants of inadequate EAMT were APACHE II score, MDRO infections, comorbidity, and surgical history. This provides valuable inputs to improve the prescription of empiric antimicrobials in Saudi Arabia going forward. In addition, our study demonstrated the potential utility of applying artificial neural network analysis in the prediction of outcomes in healthcare research.

The long and short of antibiotic management for neutropenic fever in patients with haematological malignancy

Neutropenic fever is a common complication of therapy for haematological malignancy and in about 40% of episodes, no clinical focus or microbiological cause is identified. 1 Verlinden A Jansens H Goossens H et al. Safety and efficacy of antibiotic de-escalation and discontinuation in high-risk hematological patients with febrile neutropenia: a single-center experience. Open Forum Infect Dis. 2022; 9ofab624 Crossref PubMed Scopus (6) Google Scholar , 2 Averbuch D Orasch C Cordonnier C et al. European guidelines for empirical antibacterial therapy for febrile neutropenic patients in the era of growing resistance: summary of the 2011 4th European Conference on Infections in Leukemia. Haematologica. 2013; 98: 1826-1835 Crossref PubMed Scopus (343) Google Scholar , 3 Aguilar-Guisado M Espigado I Martín-Peña A et al. Optimisation of empirical antimicrobial therapy in patients with haematological malignancies and febrile neutropenia (How Long study): an open-label, randomised, controlled phase 4 trial. Lancet Haematol. 2017; 4: e573-e583 Summary Full Text Full Text PDF PubMed Scopus (93) Google Scholar The optimal strategy for antibiotic management in the setting of neutropenic fever with no identified source is yet to be defined. Common strategies include early de-escalation from empiric therapy to antibiotic prophylaxis until neutrophil recovery or complete cessation of antibiotic therapy with different cessation thresholds used. 2 Averbuch D Orasch C Cordonnier C et al. European guidelines for empirical antibacterial therapy for febrile neutropenic patients in the era of growing resistance: summary of the 2011 4th European Conference on Infections in Leukemia. Haematologica. 2013; 98: 1826-1835 Crossref PubMed Scopus (343) Google Scholar , 4 Freifeld AG Bow EJ Sepkowitz KA et al. Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of america. Clin Infect Dis. 2011; 52: e56-e93 Crossref PubMed Scopus (2014) Google Scholar A cellular recovery threshold (neutrophil count ≥0·5×109/L) for cessation has been recommended, 4 Freifeld AG Bow EJ Sepkowitz KA et al. Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of america. Clin Infect Dis. 2011; 52: e56-e93 Crossref PubMed Scopus (2014) Google Scholar but, new data suggest the use of clinically guided cessation using clinical stability and resolution of fever for earlier antibiotic cessation. 1 Verlinden A Jansens H Goossens H et al. Safety and efficacy of antibiotic de-escalation and discontinuation in high-risk hematological patients with febrile neutropenia: a single-center experience. Open Forum Infect Dis. 2022; 9ofab624 Crossref PubMed Scopus (6) Google Scholar , 3 Aguilar-Guisado M Espigado I Martín-Peña A et al. Optimisation of empirical antimicrobial therapy in patients with haematological malignancies and febrile neutropenia (How Long study): an open-label, randomised, controlled phase 4 trial. Lancet Haematol. 2017; 4: e573-e583 Summary Full Text Full Text PDF PubMed Scopus (93) Google Scholar Earlier antibiotic cessation compared with continuation until resolution of neutropenia is associated with lower antibiotic exposure and no significant difference in rates of clinical failure, safety, or mortality. 1 Verlinden A Jansens H Goossens H et al. Safety and efficacy of antibiotic de-escalation and discontinuation in high-risk hematological patients with febrile neutropenia: a single-center experience. Open Forum Infect Dis. 2022; 9ofab624 Crossref PubMed Scopus (6) Google Scholar , 3 Aguilar-Guisado M Espigado I Martín-Peña A et al. Optimisation of empirical antimicrobial therapy in patients with haematological malignancies and febrile neutropenia (How Long study): an open-label, randomised, controlled phase 4 trial. Lancet Haematol. 2017; 4: e573-e583 Summary Full Text Full Text PDF PubMed Scopus (93) Google Scholar Short versus extended treatment with a carbapenem in patients with high-risk fever of unknown origin during neutropenia: a non-inferiority, open-label, multicentre, randomised trialEarly discontinuation of carbapenem treatment in patients with febrile neutropenia of unknown origin does not result in increased treatment failure. Our study supports short treatment if patients are afebrile after 3 days of carbapenem treatment. However, because secondary analyses suggested that serious adverse events and all-cause mortality occurred more often in patients who are persistantly febrile the short treatment group, we recommend vigilance for non-susceptible pathogens and early resumption of empirical therapy in patients who are deteriorating. Full-Text PDF

Role of the T2Dx magnetic resonance assay in patients with suspected bloodstream infection: a single-centre real-world experience

BackgroundT2Dx was approved by the US Food and Drug Administration for the rapid detection of a modified panel of ESKAPE bacterial species or Candida spp. causing bloodstream infection (BSI).Patients and methodsWe performed a retrospective, observational study from January 1, 2018 to December 31, 2019 of all hospitalised patients with suspected BSI who underwent assessment using T2Dx in addition to standard blood culture (BC). T2-positive patients (cases) were compared to a matched group of patients with BSI documented only by BC (1:2 ratio) to investigate the possible impact of T2Dx on the appropriateness of empirical antimicrobial therapy and 21-day mortality.ResultsIn total, 78 T2Dx-analysed samples (49 patients) were analysed. The T2Dx assay result was positive for18 patients and negative for 31 patients. The concordance rates of the T2Bacteria Panel and T2Candida Panel results with those of standard BC were 74.4% and 91.4%, respectively. In the matched analysis, inappropriate empiric antimicrobial therapy administration was significantly less frequent in cases than in comparators (5.5% vs. 38.8%). The 21-day mortality rate was twofold lower in cases than in comparators (22.2% vs. 44.4%), although the difference was not significant. No other analysed variables were significantly different between the two groups.ConclusionsThis study illustrated that T2Dx might be associated with an increase in the appropriateness of empiric antimicrobial therapy in patients with BSI. Further studies are needed to evaluate whether the T2Dx assay can improve patient outcomes.

P-OT027. Approach and management of suspected encephalitic patients in omdurman teaching hospital

Introduction . The aim of this study was to assess the approach and management of suspected encephalitic patients in Omdurman teaching hospital. Methods . This was a cross-sectional descriptive study, conducted on 84 patients who are suspected of encephalitis in neurology department. The data was analyzed using SPSS. Results . The commonest group of age affected (21–40) representing about 66.7% with 84.5% female predominant and most of the patients from Khartoum state (58.3%). Regarding the main presenting symptoms, 100% presented with fever and headache, 36.9% with seizure and 28.6% with agitation, other symptoms like abnormal behavior, memory disturbance, photophobia, neck stiffness and nausea / vomiting ranging from (22.6–8.3%). 1.2% has a history of SLE and also 1.2% presented with bilateral 6th cranial nerve lesion. 28.6% presented with unconsciousness and disoriented. 13.1% comatose with 20.2% had personality changes and memory disturbance. Regarding upper and lower limbs examination 13.1% hemiparesis, 4.8% quadriparesis and 1.2% paraparesis. 100% did a CBC showed lymphocyte predominant about 70.2%, 100% elevation in ESR. 71 patients did a CSF analysis with 83.1% showed abnormality, increasing lymphocyte cells, others were normal. MRI/CT scan was done in 50 patients;, in 63.2% MRI showed temporal hyperintense lesion, whereas CT scan was normal in majority of cases (71%). EEG was abnormal in 3.6% of cases. Most of the cases were managed empirically with antiviral and antibiotics, 100% and 94% respectively. About 85.7% received antiepileptic. The most common complication was seizure (85.7%). 26.2% ended up with motor deficit. Fortunately, most of the cases completely recovered (65.5%). Conclusion . The diagnostic approach to patients with encephalitis must include CSF, neuroimaging (MRI) plus or minus EEG. Empirical antimicrobial therapy for patients with suspected encephalitis should include rapid administration of intravenous acyclovir at appropriate dosages if clinically suspected despite unobtainable CSF result. We must identify the exact etiology and once an etiologic agent of encephalitis is identified, antimicrobial therapy should be targeted to that infectious agent, or therapy should be discontinued if treatment directed against the etiologic agent is not available.

Antimicrobial Susceptibility Trends and Risk Factors for Antimicrobial Resistance in Pseudomonas aeruginosa Bacteremia: 12-Year Experience in a Tertiary Hospital in Korea.

BackgroundInfections caused by multidrug-resistant Pseudomonas aeruginosa (MDRPA) have been on the rise worldwide, and delayed active antimicrobial therapy is associated with high mortality. However, few studies have evaluated increases in P. aeruginosa infections with antimicrobial resistance and risk factors for such antimicrobial resistance in Korea. Here, we analyzed changes in antimicrobial susceptibility associated with P. aeruginosa bacteremia and identified risk factors of antimicrobial resistance.MethodsThe medical records of patients with P. aeruginosa bacteremia who were admitted to a tertiary hospital between January 2009 and October 2020 were retrospectively reviewed. Antibiotic resistance rates were compared among the time periods of 2009–2012, 2013–2016, and 2017–2020 and between the intensive care unit (ICU) and non-ICU setting. Empirical antimicrobial therapy was considered concordant, if the organism was susceptible to antibiotics in vitro, and discordant, if resistant.ResultsDuring the study period, 295 patients with P. aeruginosa bacteremia were identified. The hepatobiliary tract (26.8%) was the most common primary site of infection. The rates of carbapenem-resistant P. aeruginosa (CRPA), MDRPA, and extensively drug-resistant P. aeruginosa (XDRPA) were 24.7%, 35.9%, and 15.9%, respectively. XDRPA showed an increasing trend, and CRPA, MDRPA, and XDRPA were also gradually increasing in non-ICU setting. Previous exposure to fluoroquinolones and glycopeptides and urinary tract infection were independent risk factors associated with CRPA, MDRPA, and XDRPA. Previous exposure to carbapenems was an independent risk factor of CRPA. CRPA, MDRPA, and XDRPA were associated with discordant empirical antimicrobial therapy.ConclusionThe identification of risk factors for antimicrobial resistance and analysis of antimicrobial susceptibility might be important for concordant empirical antimicrobial therapy in patients with P. aeruginosa bacteremia.

De-Escalation of Antimicrobials in Adult Hematopoietic Cell Transplantation Recipients with Febrile Neutropenia of Unknown Origin

De-Escalation of Antimicrobials in Adult Hematopoietic Cell Transplantation Recipients with Febrile Neutropenia of Unknown Origin

Risk Factors for Colistin Resistance among Gram-Negative Rods and Klebsiella pneumoniae Isolates.

Infections due to colistin-resistant (Colr) Gram-negative rods (GNRs) and colistin-resistant Klebsiella pneumoniae isolates in particular result in high associated mortality and poor treatment options. To determine the risk factors for recovery on culture of Colr GNRs and ColrK. pneumoniae, analyses were chosen to aid decisions at two separate time points: the first when only Gram stain results are available without any bacterial species information (corresponding to the Colr GNR model) and the second when organism identification is performed but prior to reporting of antimicrobial susceptibility testing results (corresponding to the ColrK. pneumoniae model). Cases were retrospectively analyzed at a major academic hospital system from 2011 to 2016. After excluding bacteria that were intrinsically resistant to colistin, a total of 28,512 GNR isolates (4,557 K. pneumoniae isolates) were analyzed, 128 of which were Colr (i.e., MIC > 2 μg/ml), including 68 of which that were ColrK. pneumoniae In multivariate analysis, risk factors for Colr GNRs were neurologic disease, residence in a skilled nursing facility prior to admission, receipt of carbapenems in the last 90 days, prior infection with a carbapenem-resistant organism, and receipt of ventilatory support (c-statistic = 0.81). Risk factors for ColrK. pneumoniae specifically were neurologic disease, residence in a skilled nursing facility prior to admission, receipt of carbapenems in the last 90 days, receipt of an anti-methicillin-resistant Staphylococcus aureus antimicrobial in the last 90 days, and prior infection with a carbapenem-resistant organism (c-statistic = 0.89). A scoring system derived from these models can be applied by providers to guide empirical antimicrobial therapy in patients with infections with suspected Colr GNR and ColrK. pneumoniae isolates.

Empirical Antibiotic Therapy Assessment of Patients diagnosed with Sepsis in Intermediate Care Ward of Internal Medicine Department of Dr. Soetomo General Hospital according to Gyssens Method

Rational empirical antimicrobial therapy is an important component of sepsis patient management. This study aimed to assess the rationality of empirical antimicrobial therapy in patients diagnosed with sepsis admitted in intermediate care ward of internal medicine department (RPI) of Dr. Soetomo General Hospital from January 2016 to July 2017. Medical records of 91 patients diagnosed with sepsis were collected and studied retrospectively in period from July 2017 to November 2017. 91 (85.05%) medical records from 107 sepsis patients were evaluated. Cultures and antimicrobial sensitivity tests were carried out in 21 (23.07%) patients. 14 patients yielded positive culture results, 9 of which were MDRO positive with ESBL as resistant marker. Empirical antibiotic therapies for these patients were reviewed according to Gyssens method.73 (80.2%) of 91 patients were deemed receiving appropriate empirical antibiotic therapies. Ceftriaxone IV injection as monotherapy or combination therapy were the most common empirical antibiotic therapies (82 in 91 patients, 90.1%), despite local microbiologic flora and antibiogram show most pathogens were resistant to ceftriaxone. Mortality rate in this study was high, 92.3% (84 patients died) despite rational empirical antibiotic therapies were high.This study concluded that empirical antibiotic therapies in sepsis patients according to guidelines adopted in Soetomo General Hospital, albeit deemed rational, was no longer appropriate according to local antibiogram issued by microbiological department of Soetomo General Hospital.

Optimisation of empirical antimicrobial therapy in patients with haematological malignancies and febrile neutropenia (How Long study): an open-label, randomised, controlled phase 4 trial

Continuation of empirical antimicrobial therapy (EAT) for febrile neutropenia in patients with haematological malignancies until neutrophil recovery could prolong the therapy unnecessarily. We aimed to establish whether EAT discontinuation driven by a clinical approach regardless of neutrophil recovery would optimise the duration of therapy. We did an investigator-driven, superiority, open-label, randomised, controlled phase 4 clinical trial in six academic hospitals in Spain. Eligible patients were adults with haematological malignancies or haemopoietic stem-cell transplantation recipients, with high-risk febrile neutropenia without aetiological diagnosis. An independent, computer-generated randomisation sequence was used to randomly enrol patients (1:1) to the experimental or control group. Investigators were masked to assignment only before randomisation. EAT based on an antipseudomonal β-lactam drug as monotherapy (ceftazidime or cefepime, meropenem or imipenem, or piperacillin-tazobactam) or as combination therapy (with an aminoglycoside, fluoroquinolone, or glycopeptide) was started according to local protocols and following international guidelines and recommendations. For the experimental group, EAT was withdrawn after 72 h or more of apyrexia plus clinical recovery; for the control group, treatment was withdrawn when the neutrophil count was also 0·5 × 109 cells per L or higher. The primary efficacy endpoint was the number of EAT-free days. Primary analyses were done in the intention-to-treat population. Efficacy and safety analyses were done in the intention-to-treat population and the per-protocol population. This trial is registered with ClinicalTrials.gov, number NCT01581333. Between April 10, 2012, and May 31, 2016, 157 episodes among 709 patients assessed for eligibility were included in analyses. 78 patients were randomly assigned to the experimental group and 79 to the control group. The mean number of EAT-free days was significantly higher in the experimental group than in the control group (16·1 [SD 6·3] vs 13·6 [7·2], absolute difference -2·4 [95% CI -4·6 to -0·3]; p=0·026). 636 adverse events were reported (341 in the experimental group vs 295 in the control group; p=0·057) and most (580 [91%]; 323 in the experimental group vs 257 in the control group) were considered mild or moderate (grade 1-2). The most common adverse events in the experimental versus the control group were mucositis (28 [36%] of 78 patients vs 20 [25%] of 79 patients), diarrhoea (23 [29%] of 78 vs 24 [30%] of 79), and nausea and vomiting (20 [26%] of 78 vs 22 [28%] of 79). 56 severe adverse events were reported, 18 in the experimental group and 38 in the control group. One patient died in the experimental group (from hepatic veno-occlusive disease after an allogeneic haemopoietic stem-cell transplantation) and three died in the control group (one from multiorgan failure, one from invasive pulmonary aspergillosis, and one from a post-chemotherapy intestinal perforation). In high-risk patients with haematological malignancies and febrile neutropenia, EAT can be discontinued after 72 h of apyrexia and clinical recovery irrespective of their neutrophil count. This clinical approach reduces unnecessary exposure to antimicrobials and it is safe. Instituto de Salud Carlos III, Spanish Ministry of Economy (PI11/02674).

Resistance profiles and risk factors of resistant microorganisms in bacteraemia of abdominal origin

Abstract Objective The presence of resistant microorganisms is a major cause of failure in initial empirical antimicrobial therapy. The objectives of this study are to determine the resistance profile of microorganisms that cause bacteraemia of abdominal origin and to identify whether the previous use of antibiotics and the place of acquisition of bacteraemia are risk factors associated with the presence of resistant organisms. Material and methods A clinical, observational, epidemiological, retrospective cohort study was conducted with all the adult patients admitted to a university hospital from 2011 to 2013. Antimicrobial resistance profiles were described and a 95% confidence interval chi-square test was used to determine whether the variables studied were risk factors in the isolation of resistant microorganisms. Results Of the 1245 patients with bacteraemia, 212 (17%) presented bacteraemia of abdominal origin. The resistance profile highlights the incidence of methicillin resistant Staphylococcus aureus (50%), coagulase-negative staphylococci resistant to linezolid (20.58%), enterococci resistant to vancomycin (3.12%), Escherichia coli resistant to third-generation cephalosporins (9.9%) and fluoroquinolones (35.64%), Klebsiella pneumoniae resistant to third-generation cephalosporins (8.33%), Pseudomonas aeruginosa resistant to fluoroquinolones and carbapenem (25% and 25% respectively) and Acinetobacter baumanii resistant to fluoroquinolones and carbapenem (100% and 100% respectively), Candida albicans resistant to fluconazole (11.11%), single Candida krusei isolate resistant to fluconazole and Candida parapsilosis resistant to echinocandins (12.5%). In our study, previous use of antibiotics had a statistically significant association with the isolation of resistant microorganisms (p = 0.013) but not the place of acquisition of bacteraemia (p = 0.239). Conclusion Establishing the incidence of resistant organisms can improve empirical antimicrobial therapy in patients with bacteraemia of abdominal origin. Previous use of antibiotics was statistically significantly related to the isolation of resistant microorganisms.

Effect of antibiotics for infectious diarrhea on the duration ofhospitalization: A retrospective cohort study at a single centerinJapan from 2012 to 2015.

Routine empirical antimicrobial therapy for patients with infectious diarrhea is not recommended in general practice. Conversely, prescription of empirical antibiotics for hospitalized patients remains controversial due to a lack of studies providing evidence for its benefits. Thus, this study aimed to examine whether empirical antimicrobial therapy would shorten the hospitalization duration for infectious diarrhea patients. This single-center, retrospective cohort study was performed at the Department of General Medicine and Emergency Care, Toho University Medical Center Omori Hospital, using medical records. Adult patients (aged ≥16 years) hospitalized for infectious diarrhea from 2012 to 2015 were enrolled. The primary outcome was the duration of hospitalization. Risk factors examined in parallel to antibiotic therapy included age, sex, relevant medical history, probiotics use, vital signs, leukocyte count, liver and renal functions, and microbiological data. We enrolled 138 and 50 patients treated with and without antimicrobial therapy, respectively. The median hospitalization periods were 6.0 days (interquartile range, 4.0-7.0 days) and 5.0 days (interquartile range, 3.25-6.0 days) for patients treated with and without antibiotics, respectively (p=0.007). Multiple regression showed that empiric antimicrobial therapy (p=0.017), advanced age (p=0.003), hematochezia (p=0.008), elevated serum creatinine (p<0.001), and elevated serum C-reactive protein (p=0.002) were significant risk factors of longer hospitalization duration. Empirical antimicrobial therapy was found to relate to a longer hospitalization duration for infectious diarrhea patients. Although its effects on the patients' symptoms were not evaluated, our results suggest that empirical antimicrobial therapy should be administered cautiously to not only outpatients, but also hospitalized patients.

Clinical Epidemiology of Septic Arthritis Caused by Burkholderia pseudomallei and Other Bacterial Pathogens in Northeast Thailand.

.Septic arthritis is a medical emergency, and if not treated appropriately, it can be associated with high morbidity and mortality. Melioidosis, a serious infectious disease caused by the Gram-negative bacillus Burkholderia pseudomallei, is highly endemic in South and Southeast Asia and northern Australia. We reviewed the medical charts of adult patients admitted with bacterial septic arthritis at Sunpasitthiprasong Hospital, Ubon Ratchathani, northeast Thailand from January 2012 to December 2014. Bacterial septic arthritis was defined as one or more hot swollen joints with isolation of a pathogenic organism from an affected joint or from blood. A total of 154 patients with septic arthritis were retrospectively evaluated. The most common causes were B. pseudomallei (48%, N = 74), Streptococcus spp. (29%, N = 44), and Staphylococcus aureus (10%, N = 16). Prevalence of diabetes, bacteremia, and pneumonia was higher in B. pseudomallei septic arthritis than in septic arthritis caused by the other bacteria (all P < 0.01). Seventy three percent (54/74) of patients infected with B. pseudomallei and 69% (55/80) of patients with the other bacteria received effective antimicrobials on the first day of admission (P = 0.60), but in-hospital mortality of the former group was considerably higher (34% versus 14%, P = 0.004). In conclusion, B. pseudomallei septic arthritis is common and associated with high mortality in northeast Thailand. Emergence of Streptococcus arthritis is observed. Difficulty in diagnosing melioidosis and identifying B. pseudomallei in areas where health care workers are not familiar with the disease is discussed. In melioidosis-endemic regions, parenteral ceftazidime could be considered as empirical antimicrobial therapy for patients with septic arthritis and underlying diseases.

Perfiles de resistencia y factores de riesgo de microorganismos resistentes en bacteriemia de origen abdominal

ObjectiveThe presence of resistant microorganisms is a major cause of failure in initial empirical antimicrobial therapy. The objectives of this study are to determine the resistance profile of microorganisms that cause bacteraemia of abdominal origin and to identify whether the previous use of antibiotics and the place of acquisition of bacteraemia are risk factors associated with the presence of resistant organisms. Material and methodsA clinical, observational, epidemiological, retrospective cohort study was conducted with all the adult patients admitted to a university hospital from 2011-2013. Antimicrobial resistance profiles were described and a 95% confidence interval chi-square test was used to determine whether the variables studied were risk factors in the isolation of resistant microorganisms. ResultsOf the 1245 patients with bacteraemia, 212 (17%) presented bacteraemia of abdominal origin. The resistance profile highlights the incidence of methicillin resistant Staphylococcus aureus (50%), coagulase-negative staphylococci resistant to linezolid (20.58%), enterococci resistant to vancomycin (3.12%), Escherichia coli resistant to third-generation cephalosporins (9.9%) and fluoroquinolones (35.64%), Klebsiella pneumoniae resistant to third-generation cephalosporins (8.33%), Pseudomonas aeruginosa resistant to fluoroquinolones and carbapenem (25% and 25% respectively) and Acinetobacter baumanii resistant to fluoroquinolones and carbapenem (100% and 100% respectively), Candida albicans resistant to fluconazole (11.11%), single Candida krusei isolate resistant to fluconazole and Candida parapsilosis resistant to echinocandins (12.5%). In our study, previous use of antibiotics had a statistically significant association with the isolation of resistant microorganisms (P=.013) but not the place of acquisition of bacteraemia (P=.239). ConclusionEstablishing the incidence of resistant organisms can improve empirical antimicrobial therapy in patients with bacteraemia of abdominal origin. Previous use of antibiotics was statistically significantly related to the isolation of resistant microorganisms.

Association between inappropriate empirical antimicrobial therapy and hospital length of stay in Gram-negative bloodstream infections: stratification by prognosis.

The potential benefit from appropriate empirical antimicrobial therapy in patients with favourable prognosis at initial presentation with Gram-negative bloodstream infection (BSI) remains unclear. This retrospective cohort study examined the impact of inappropriate empirical antimicrobial therapy on hospital length of stay (HLOS) following Gram-negative BSI after stratification by predicted prognosis using the BSI mortality risk score (BSIMRS). Hospitalized adults with first episodes of Gram-negative BSI from 1 January 2010 to 31 December 2013 at Palmetto Health Hospitals in Columbia, SC, USA were identified. Multivariate Cox proportional hazards regression was used to examine the association between inappropriate empirical antimicrobial therapy and HLOS overall and within each predefined BSIMRS category (<5 and ≥5). Among 830 unique patients with Gram-negative BSI, 469 and 361 had BSIMRS <5 and ≥5, respectively. Overall, the median age was 65 years, 448 (54%) were women, Escherichia coli (444; 53%) was the most common bloodstream isolate and 444 (53%) had a urinary source of infection. After adjustments in the multivariate model, BSIMRS (HR = 1.14 per point, 95% CI = 1.11-1.17, P < 0.001) and inappropriate empirical antimicrobial therapy (HR = 1.41, 95% CI = 1.07-1.91, P = 0.01) were independently associated with increased risk of remaining hospitalized following Gram-negative BSI. Median HLOS with appropriate and inappropriate empirical antimicrobial therapy was 7 and 10 days, respectively, in patients with BSIMRS <5 (P = 0.03) and 13 and 17 days, respectively, in those with BSIMRS ≥5 (P = 0.02). Inappropriate empirical antimicrobial therapy is associated with prolonged HLOS following Gram-negative BSI in patients with both good and guarded prognosis.

Risk factors and outcomes of afebrile bacteremia patients in an emergency department

ObjectiveThere is limited research on afebrile bacteremia. We aimed to compare the risk factors and outcomes of patients with afebrile and febrile infections. MethodsThis was a retrospective cohort study of bloodstream isolates from 994 adults admitted to the emergency department of a university hospital. Afebrile infections, defined as the absence of fever history or measured fever through the emergency department course, was compared with febrile infection. Frequencies and proportions of sources of infection, comorbidities, along with organ failure and mortality were presented. The major outcome measure was 30-day survival. chi-Square or Student's t test was used for univariate analysis, and Cox proportional hazard model was used for multivariate analysis. ResultsWe found that the risk factors and outcomes of febrile and afebrile bacteremia patients were very different. The afebrile patients were older, have higher Charlson comorbidity index, and had poorer outcomes than the febrile patients. We also found that oldest old age, nonhematologic malignancy, necrotizing fasciitis, spontaneous bacterial peritonitis, and pneumonia were each positive independent predictors of afebrile bacteremia, whereas Escherichia coli infection and liver abscess were independent negative predictors of afebrile bacteremia. Finally, the 30-day all-cause mortality was higher in the afebrile group than in the febrile group (45% versus 12%, log-rank P<0.001). ConclusionsThis series of patients with afebrile bacteremia confirmed the previously reported associations with old age and immunocompromised conditions. Clinicians should explore the possibility of occult severe infection, and initiate early hemodynamic support and empirical antimicrobial therapy for patients with the aforementioned risk factors.

Estimating the likelihood of success with the initial empiric antimicrobial therapy in patients with nosocomial infections

In order to estimate the likelihood of success (SL) with the initial empiric antimicrobial therapy, the following formula was constructed with data subjected to prior clinical validation in real time: SL (%) = (Nº isolates susceptible to IEAT/Nº patients with MDI) × 100. Where the numerator of the formula represents the total number of isolates recovered from the assessed type of infection, that was susceptible to any component of empiric antimicrobial therapy (IEAT) used, and the denominator represents the total number of patients with the same assessed, but microbiologically documented infection (MDI). For male hospital-acquired urinary tract infection, only imipenem reached a suitable SL value (i.e. ≥80%). In patients with hospital-acquired peritonitis, imipenem and tigecycline–ceftazidime showed the highest coverage rates. For ventilator-associated pneumonia only imipenem yielded acceptable coverage as a single drug. Implementing the present formula instead of the regular global antibiograms used to guide the selection of the initial treatment may benefit the patient outcome and improve antimicrobial usage.

Is admission screening for Pseudomonas aeruginosa useful in haematologic patients? A prospective study with 1310 patients

Screening for Pseudomonas aeruginosa is recommended to guide empirical antimicrobial therapy in patients on high-risk units. However, evidence for this approach is scarce. We therefore screened 1310 patients with severe haematologic diseases for P. aeruginosa colonization at admission: 108 (8.2%) were positive, but only nine (0.7%; six with the same clone as in the screening isolate) subsequently developed a P. aeruginosa bloodstream infection (positive predictive value of screening, 8.6%; negative predictive value of screening, 99.5%). Routine screening for P. aeruginosa at admission did not sufficiently predict subsequent bloodstream infections caused by P. aeruginosa.

Evaluation of the decision support system for antimicrobial treatment, TREAT, in an acute medical ward of a university hospital

TREAT, a decision support system for antimicrobial therapy, was implemented in an acute medical ward. Patients admitted on suspicion of infection were included in the study. The evaluation of TREAT was done both retrospectively and prospectively. Coverage of empirical antimicrobial treatments was compared to recommendations from TREAT and the optimal use of local guidelines. Five hundred and eleven patients were included, of whom 162 had a microbiologically documented infection. In the retrospective part of the study, TREAT, physician, and guideline antimicrobial coverage rates were 65%, 51%, and 79%, respectively, and in the prospective part, 68%, 62%, and 77%, respectively. TREAT provided lower coverage than local guidelines (p<0.001), but was similar to the performance of physicians in a university hospital (p=0.069). No differences were found in length of hospital stay, or hospital or 30-day mortality. Direct costs were significantly higher for TREAT advice than for local guidelines or the physician prescriptions (p<0.001), but the ecological costs were lower for TREAT advice than for both local guidelines (p<0.001) and physician prescriptions (p=0.247). The coverage of TREAT advice for the bacteraemia patients was non-inferior to the physicians (p=1.00). TREAT can potentially improve the ecological costs of empirical antimicrobial therapy for patients in acute medical wards, but provided lower coverage than local guidelines.

Antimicrobial Resistance of Uropathogens and Rationale for Empirical Therapy in Jordan

Urinary tract infection (UTI) is one of the most common infections in both outpatients and hospital patients. In the majority of the cases, antimicrobial treatment is usually started empirically before the laboratory results of the urine culture are available. Thus, antimicrobial resistance may increase in uropathogens due to frequent and improper use of antimicrobial agents. This study was conducted to identify the urinary pathogens of UTI, to determine the antimicrobial resistance pattern in UTI and to assess the choices available for empirical antimicrobial therapy in patients with UTI over a three-year period. This study was conducted at King Abdulla University Hospital, Irbid in the north of Jordan from 2003 to 2005. A retrospective analysis of data taken from all midstream urine samples (8,800 patients suspected of UTI) was analyzed and an antimicrobial susceptibility test for commonly usable antimicrobial agents was performed for the isolates using the standard disc diffusion method. Data was analyzed using SPSS software window version 12. The most frequent causative organisms isolated were Escherichia coli (48.2%), Klebsiella pneumoniae (14.5%), Pseudomonas aeruginosa (9.7%), Enterococcus faecalis (5.8%), and Proteus mirabilis (3.2%). Nitrofurantoin was found to be the most effective antimicrobial agent against E. coli, Klebsiella pneumonia and Enterococcus faecalis isolates. Gentamycin and ciproflaxcin were found to be the most effective antimicrobial agents against Pseudomonas aeruginosa. The progressive increase in antimicrobial resistance among patients with UTI is of great concern. Empirical antimicrobial selection should be based on knowledge of the local prevalence of bacterial organisms and antimicrobial sensitivities, because antimicrobial resistance patterns may vary in different regions. The findings of this study indicate that E. coli is the predominant pathogen of UTI. Moreover, nitrofurantoin should be considered for empirical therapy of lower tract UTI.