Emergence of concurrent levofloxacin- and trimethoprim/sulfamethoxazole-resistant Stenotrophomonas maltophilia: Risk factors and antimicrobial sensitivity pattern analysis from a single medical center in Taiwan

BackgroundThe emergence of concurrent levofloxacin- and trimethoprim/sulfamethoxazole (TMP/SMX)-resistant Stenotrophomonas maltophilia (LTSRSM) in Taiwan is becoming a serious problem, but clinical data analysis on this has not been reported.MethodsA matched case-control-control study was conducted to investigate risk factors for LTSRSM occurrence in hospitalized patients. For patients with LTSRSM infection/colonization (the case group), two matched control groups were used: control group A with levofloxacin- and TMP/SMX-susceptible S. maltophilia (LTSSSM) and control group B without S. maltophilia. Besides, tigecycline, ceftazidime, cefepime, ciprofloxacin, gentamicin, amikacin, and colistin susceptibilities in collected LTSRSM and levofloxacin- and TMP/SMX-susceptible S. maltophilia (LTSSSM) isolates were compared.ResultsFrom January 2014 to June 2016, 129 LTSRSM from cultured 1213 S. maltophilia isolates (10.6%) were identified. A total of 107 LTSRSM infected patients paired with 107 LTSSSM-, and 107 non-S. maltophilia-infected ones were included. When compared with control group A, previous fluoroquinolone and TMP/SMX use was found to be independently associated with LTSRSM occurrence. When compared with control group B, mechanical ventilation, cerebrovascular disease, and previous fluoroquinolone use were risk factors for LTSRSM occurrence. Eighty-five LTSRSM and 85 LTSSSM isolates were compared for antibiotic susceptibilities; the resistance rates and minimum inhibitory concentrations of tigecycline and ceftazidime were significantly higher for LTSRSM than for LTSSSM isolates.ConclusionThe emergence of LTSRSM showing cross resistance to tigecycline and ceftazidime would further limit current therapeutic options. Cautious fluoroquinolone and TMP/SMX use may be helpful to limit such high-level resistant strains of S. maltophilia occurrence.     

Advances in the therapy of bacterial bloodstream infections

BackgroundAdvances in the diagnostic and therapeutic management of patients with bloodstream infections (BSIs) have been achieved in the last years, improving clinical outcome. However, mortality associated with some pathogens, such as Staphylococcus aureus and Enterococcus spp., is still high. In addition, the spread of antibiotic resistance, mainly among Gram-negative bacteria, reduces treatment options in some circumstances. Therefore, interest in new drugs, combination regimens and optimal dosing schedules is rising.ObjectivesOur aim is to summarize the current evidence on available antibiotic regimens for patients with bacterial BSI, focusing on drug choice, combination regimens and optimal dosing schedules. We selected bacteria that are difficult to manage because of virulence factors (i.e. methicillin-susceptible S. aureus), tolerance to antibiotic activity (i.e. Enterococcus faecalis), and/or susceptibility patterns (i.e. methicillin-resistant S. aureus, vancomycin-resistant enterococci, carbapenem-resistant Enterobacteriaceae, multidrug-resistant Pseudomonas aeruginosa and carbapenem-resistant Acinetobacter baumannii).SourcesMEDLINE search with English language and publication in the last 5 years as limits.Content and implicationsThe literature gaps on the use of new drugs, the uncertainties regarding the use of combination regimens, and the need to optimize dosing schedules in some circumstances (e.g. augmented renal clearance, renal replacement therapy, high inoculum BSI sources, and isolation of bacteria showing high MICs) have been revised.     

A prospective multicentre study of the epidemiology and outcomes of bloodstream infection in cirrhotic patients

ObjectivesTo describe the current epidemiology of bloodstream infection (BSI) in patients with cirrhosis; and to analyse predictors of 30-day mortality and risk factors for antibiotic resistance.MethodsCirrhotic patients developing a BSI episode were prospectively included at 19 centres in five countries from September 2014 to December 2015. The discrimination of mortality risk scores for 30-day mortality were compared by area under the receiver operator risk and Cox regression models. Risk factors for multidrug-resistant organisms (MDRO) were assessed with a logistic regression model.ResultsWe enrolled 312 patients. Gram-negative bacteria, Gram-positive bacteria and Candida spp. were the cause of BSI episodes in 53%, 47% and 7% of cases, respectively. The 30-day mortality rate was 25% and was best predicted by the Sequential Organ Failure Assessment (SOFA) and Chronic Liver Failure–SOFA (CLIF-SOFA) score. In a Cox regression model, delayed (>24 hours) antibiotic treatment (hazard ratio (HR) 7.58; 95% confidence interval (CI) 3.29–18.67; p < 0.001), inadequate empirical therapy (HR 3.14; 95% CI 1.93–5.12; p < 0.001) and CLIF-SOFA score (HR 1.35; 95% CI 1.28–1.43; p < 0.001) were independently associated with 30-day mortality. Independent risk factors for MDRO (31% of BSIs) were previous antimicrobial exposure (odds ratio (OR) 2.91; 95% CI 1.73–4.88; p < 0.001) and previous invasive procedures (OR 2.51; 95% CI 1.48–4.24; p 0.001), whereas spontaneous bacterial peritonitis as BSI source was associated with a lower odds of MDRO (OR 0.30; 95% CI 0.12–0.73; p 0.008).ConclusionsMDRO account for nearly one-third of BSI in cirrhotic patients, often resulting in delayed or inadequate empirical antimicrobial therapy and increased mortality rates. Our data suggest that improved prevention and treatment strategies for MDRO are urgently needed in the liver cirrhosis patients.     

Treatment duration for Escherichia coli bloodstream infection and outcomes: retrospective single-centre study

ObjectivesTo investigate the impact of treatment duration on mortality and on relapse in patients with Escherichia coli bloodstream infection (BSI).MethodsRetrospective single-centre study of patients diagnosed with E. coli BSI at our centre over a 4-year period. Exclusion criteria: age <18 years, clinical data not available, polymicrobial BSI, failure to receive in vitro active therapy, and death while receiving antibiotic therapy. Exposure variable was treatment duration dichotomized into short (≤10 days) and long (>10 days) therapy. Primary end point was all-cause mortality within 90 days after index BSI. Secondary end point was relapse, defined as repeat isolation of E. coli from blood cultures within 90 days after index BSI, in patients with documented clinical cure and completion of therapy for the initial episode.ResultsOf the 856 analysed patients: 426 received short and 430 received long therapy. All-cause mortality at day 90 occurred in 47 patients; on multivariate analysis, short therapy was not associated with a higher risk of mortality, also after adjusting the model for the propensity score of receiving short therapy. Relapse occurred in 42 patients. Independent risk factors for relapse using death as competing risk were immunosuppression (subhazard ratio 4.67, p < 0.001), and end-stage liver disease (subhazard ratio 2.58, p 0.013). The propensity-weighted estimation of the average treatment effect for relapse reduction with long therapy (>10 days) was –1.6% (p 0.26) in the total population, and –7.1% (p 0.18) in immunocompromised patients.ConclusionsWe could not identify shorter treatment duration as a risk factor for mortality and for relapse in patients with E. coli BSI.     

Comparison of Clinical Outcomes for Glycopeptides and Beta-Lactams in Methicillin-Susceptible Staphylococcus Aureus Bloodstream Infections

PurposeThis study aimed to provide compelling evidence of anti-staphylococcal beta-lactam use for methicillin-susceptible Staphylococcus aureus bloodstream infection (MSSA BSI).Materials and MethodsWe retrospectively collected data on patients with MSSA BSI who were admitted to two academic tertiary-care hospitals from 2010 to 2018. Only patients who received nafcillin, cefazolin, vancomycin, or teicoplanin as definitive therapy were included. The primary outcome was 28-day mortality. To perform unbiased comparisons between both treatments, we used inverse probability of treatment weighting (IPTW) analysis.ResultsA total of 359 patients were divided into two groups based on the definitive therapy used: beta-lactams (n=203), including nafcillin or cefazolin; and glycopeptides (n=156), including vancomycin or teicoplanin. In the IPTW analysis, glycopeptides were associated with significantly increased odds of 28-day mortality (adjusted odds ratio, 3.37; 95% confidence interval, 1.71–6.61; p<0.001). The rate of primary outcome in prespecified subgroups was largely consistent with the main analysis.ConclusionDefinitive therapy with beta-lactams in patients with MSSA BSI was associated with lower 28-day mortality compared to definitive therapy with glycopeptides.     

Integration of antimicrobial stewardship intervention with rapid organism identification improve outcomes in adult patients with bloodstream infections

BackgroundIntegration of antimicrobial stewardship intervention (ASI) with rapid organism identification has the potential for early customization of antimicrobial therapy and improved clinical outcomes. We aimed to evaluate the impact of this combined approach on antimicrobial therapy-related outcomes in patients with bloodstream infections (BSIs).Materials and methodsA pre–post quasi-experimental study was conducted to analyze the impact of ASI with organism identification via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) among patients with BSIs. Outcomes were compared to a historic pre-intervention group. The 30-day mortality was the primary endpoint. Secondary outcomes included time to first antibiotic modification, length of hospital stay.ResultsA total of 1004 adult patients with BSIs were included in the final analysis, 519 patients classified into the intervention group and 485 patients in the preintervention group. The patients in the intervention group were younger (66 vs. 70 years, P = 0.02). The 30-day crude mortality (14.6% vs. 29.9%, P < 0.001) was lower, the time to organism identification (72.25 vs. 83.6 h, P < 0.001) and length of hospital stay (12 days vs. 14 days, P < 0.001) were shorter in the intervention group. Acceptance of an ASI was associated with a trend toward a reduced 30-day mortality on multivariable analysis (odds ratio 0.33; 95% CI: 0.24–0.47; P < 0.001).ConclusionThe ASI combined with MALDI-TOF-MS approach decreased time to organism identification and time to appropriate antimicrobial therapy would achieve a better clinical outcome in the patients with BSIs.     

<Emphasis Type="Italic">Stenotrophomonas maltophilia</Emphasis> pneumonia in cancer patients without traditional risk factors for infection, 1997–2004

In order to elucidate the spectrum of Stenotrophomonas maltophilia pneumonia in cancer patients without traditional risk factors, 44 cancer patients (cases) with S. maltophilia pneumonia in whom S. maltophilia pneumonia risk factors were not present were compared with two S. maltophilia pneumonia risk groups (controls) including 43 neutropenic non-intensive care unit (ICU) and 21 non-neutropenic ICU patients. The case and control patients had similar demographic and underlying clinical characteristics. Compared with case patients with S. maltophilia pneumonia, neutropenic patients had higher exposure to carbapenem antibiotics (58 vs. 41%; p < 0.03), more frequent hematologic malignancy (95 vs. 64%; p < 0.0003), and they presented with concurrent bacteremia more often (23 vs. 0%; p < 0.0005). Patients with S. maltophilia pneumonia in the ICU needed vasopressor therapy more frequently than cases (62 vs. 5%; p < 0.0001). Hospital-acquired S. maltophilia pneumonia was more common among controls than cases (98 vs. 61%; p < 0.000002). Among the cases, 15 (34%) received outpatient oral antimicrobial therapy, while 29 were hospitalized and eight (28%) were subsequently admitted to the ICU. The mean duration of ICU stay, even among these eight patients (19 ± 40 days), was comparable to that of patients with neutropenia (23 ± 26 days) and those who developed S. maltophilia pneumonia during their ICU stay (34 ± 22 days; p = 0.46). The overall infection-associated mortality in the 108 patients with S. maltophilia pneumonia was 25%. Twenty percent of patients without traditional risk factors for S. maltophilia pneumonia died due to progressive infection. In a multivariate logistic regression analysis, only admission to the ICU predicted death (odds ratio 33; 95% confidence interval, 4.51–241.2; p < 0.0006). The results of this study indicate S. maltophilia pneumonia is a serious infection even in non-neutropenic, non-ICU patients with cancer. This work was presented in part at the 15th European Congress of Clinical Microbiology and Infectious Diseases, Copenhagen, Denmark, April 2–5, 2005 (abstract no P1374) and at the 45th Annual Interscience Conference on Antimicrobial Agents and Chemotherapy, Washington D.C., December 16–19, 2005 (abstract no K-1535).     

Ignorance of pre-ED healthcare setting is a factor leading to inappropriate initial antibiotic treatment of sepsis in ED and poor outcomes in ICU

ObjectivesAppropriate initial antibiotic therapy is critical for successfully treating sepsis. In the emergency department (ED), clinicians often rely on septic symptoms to guide empirical therapy. The aim of this study was to investigate whether history of contacting pre-ED healthcare setting is easy to be neglected and whether the patients received more inappropriate initial antibiotic therapy and developed poorer outcomes.MethodsSeptic patients (n = 453) admitted from ED to the intensive care unit (ICU) between 2014 and 2017 were retrospectively selected. Appropriate antibiotic treatment or not was determined by checking whether the selected antibiotics can effectively eradicate the bacteria identified. Various indexes were compared between patients with appropriate and inappropriate initial antibiotic treatments, including septic symptoms (qSOFA scores) in ED, septic-severity change in ICU (SOFA-score ratios), and septic outcomes (APACHE II scores, stay length, 30-day survival probability). These indexes were also compared between pre-ED healthcare and pre-ED community patients.ResultsIn comparison with pre-ED community patients, pre-ED healthcare patients received more inappropriate initial antibiotic treatment in ED, showing poorer outcomes in ICU, including septic severity, stay-lengths in ICU and 30-day survival probabilities. Pre-ED settings is more significant than qSOFA scores to predict the inappropriate initial antibiotic treatment.ConclusionsPre-ED healthcare settings, which are indexes for infection with antibiotic resistant pathogens, are easy to be neglected in the first hour in ED. We suggested that standard operating procedure for getting enough information of pre-ED settings should be incorporated to the 1 h bundle of sepsis guideline.     

Comparisons of clinical features and outcomes between Elizabethkingia meningoseptica and other glucose non-fermenting Gram-negative bacilli bacteremia in adult ICU patients

BackgroundClinical information of Elizabethkingia meningoseptica (EM) bacteremia in intensive care unit (ICU) patients is limited and the impact on outcomes uncertain. The aim of this study was to investigate the clinical features and impact of EM bacteremia compared to other glucose non-fermenting Gram-negative bacilli (GNF-GNB) bacteremia in ICU patients.MethodsThis retrospective cohort study enrolled 70 patients who developed GNF-GNB bacteremia after ICU admission, including 19 cases of EM bacteremia (19/70, 27.1%). The main outcome measure was in-hospital mortality.ResultsThe patients with EM bacteremia had a lower rate of appropriate antibiotic therapy (15.8% vs. 62.7%, p < 0.001) and a longer time to appropriate antibiotic therapy (76.8 ± 46.4 vs. 35.1 ± 38.7 h, p < 0.001), but with a less severity in acute physiology and chronic health evaluation (APACHE) II score and shock status (p < 0.05) at the onset of bacteremia, compared to those with non-EM bacteremia. The in-hospital mortality between those with EM bacteremia and non-EM bacteremia was similar (63.2% vs. 51.0%, p = 0.363). However, primary bacteremia was more frequently noted in EM compared with non-EM group (57.9% vs. 25.5%, p = 0.011), and odds ratio 4.294 (95% confidence interval 1.292–14.277, p = 0.017) in multivariate regression analysis.ConclusionAmong the patients with GNF-GNB bacteremia, the numbers of the cases with primary bacteremia and inappropriate therapy were significantly more in EM group than those in non-EM group.     

Stenotrophomonas isolates in a tertiary care centre in South India

PurposeStenotrophomonas maltophilia is an emerging multi-drug resistant pathogen increasingly isolated in India. This study aimed to identify patients from whom Stenotrophomonas maltophilia had been isolated and assess predictors of mortality in this population.MethodsThis was a retrospective cohort study of hospitalized patients with a positive culture for S. maltophilia over a 3-year period. Clinical details and laboratory results were assessed from hospital records. Bivariate and multivariate analysis was used to identify risk factors for mortality.ResultsOne hundred and nineteen patients (mean age 48.6 years) were included in the study. Of these, 111 patients were hospitalized for at least 48 ?hours prior to culture and 98 were admitted in the intensive care unit. Bivariate analysis revealed multiple associations with mortality, including a background of renal, cardiac, autoimmune disease, recent carbapenam use and COVID-19 infection and increasing ventilatory requirement, lower PaO₂/FiO₂ (P/F) ratio, vasopressor use, thrombocytopenia, and hypoalbuminemia at the time of positive isolate. Multivariate analysis showed that autoimmune disease [OR 27.38; 95% CI (1.39–540)], a P/F ratio of less than 300 [OR 7.58; 95% CI (1.52–37.9)], vasopressor requirement [OR 39.50; 95% CI (5.49–284)] and thrombocytopenia [OR 11.5; 95% CI (2.04–65.0)] were statistically significantly associated with increased mortality, while recent surgery and receipt of antibiotics [OR 0.16; 95% CI (0.03–0.8)] targeted against S. maltophilia were associated with decreased mortality.ConclusionStenotrophomonas maltophilia is primarily isolated in patients in the intensive care unit. In our study the need for vasopressors, autoimmune disease, lower P/F ratios and thrombocytopenia were associated with higher mortality. The association of targeted antibiotics with reduced mortality suggests that the pathogenic role of S. maltophilia should not be underestimated. This finding needs to be confirmed with larger, prospective studies.     

Impact of a computerized alert system for bacteremia notification on the appropriate antibiotic treatment of Staphylococcus aureus bloodstream infections

A computerized alert system (CAS) has been introduced to notify bacteremia in real time. We evaluated the impact of the CAS on the administration of appropriate antibiotics in patients with Staphylococcus aureus bloodstream infections (BSIs). We retrospectively reviewed the medical records of patients with S. aureus BSI for each 1-year control and intervention periods, before and after the implementation of the CAS. The proportions of appropriate antibiotic treatment were compared between the control and intervention periods. The 30-day mortality of S. aureus bacteremia was also assessed in the study population. A total of 313 patients were included in the study. Appropriate antibiotics were initiated 7 h earlier in the intervention period (mean time, 13.5 h vs. 20.0 h; p?=?0.136). The administration of appropriate antibiotics within the 24 h after blood acquisition was similar between the two periods, but this significantly increased from 3.3 % in the control period to 10.6 % in the intervention during the 24–36 h interval (p?=?0.012). In the subgroup analysis, similar trends were observed in patients with methicillin-resistant isolates (6.7 % vs. 18.2 %; p?=?0.032) and hospital-onset infection (3.5 % vs. 17.1 %; p?=?0.004). The independent risk factors for 30-day mortality of S. aureus bacteremia were age, a high Pitt bacteremia score, an increased Charlson’s weighted index of comorbidity, and hospital-onset infection, although the appropriateness of antibiotic therapy within 36 h and the CAS were not identified as predictors. The CAS increased the proportion of appropriate antimicrobial therapy during the 24–36 h interval after bacteremia onset in patients with S. aureus BSIs.     

Statins are associated with improved outcomes of bloodstream infection in solid-organ transplant recipients

Among recipients of intra-abdominal solid-organ transplants, bloodstream infections (BSIs) are a major cause of mortality. We undertook a retrospective cohort study of recipients of kidney, pancreas, and/or liver transplants with BSIs at a single center over an 11-year period. Multivariate analysis using logistic regression was used to determine independent predictors of 15-day mortality and clinical cure, with a focus on the use of statins. Three hundred and eleven recipients of solid-organ transplants had 604 episodes of BSI. Forty-four (14%) died within 15 days of BSI. Sixteen percent did not achieve clinical cure. In the multivariate model, each one point increase in the APACHE score was associated with a 1.09-fold increased risk of death (95% confidence interval [CI] 1.00–1.18, P = 0.03). The lack of appropriate antibiotic therapy was associated with a four-fold higher risk of death within 15 days (odds ratio [OR] 4.65, 95% CI 1.46–14.78, P = 0.009). Statin use was protective (OR 0.18, 95% CI 0.04–0.78). Patients with high APACHE scores, nosocomial rather than community source of BSI, lack of appropriate antibiotic therapy, and mental status changes were less likely to achieve clinical cure of their BSIs. In conclusion, appropriate antibiotic therapy and statin use are associated with lower risk of mortality from BSIs in this patient population.     

Transition from intravenous to oral antimicrobial therapy in patients with uncomplicated and complicated bloodstream infections

BackgroundThe role of oral antimicrobial agents in the management of bloodstream infections (BSI) is currently evolving.ObjectivesThis narrative review summarizes and appraises clinical studies that examined transition from intravenous to oral antimicrobials or compared effectiveness of various oral agents for definitive therapy of uncomplicated and complicated BSI in adults.SourcesRelevant English-language studies from MEDLINE (since inception) and presented abstracts at international scientific meetings (since 2017).ContentEmerging data suggest potential utility of oral switch strategy, particularly to oxazolidinones, as an alternative to standard intravenous therapy in low-risk patients with uncomplicated Staphylococcus aureus BSI. Moreover, results of recent randomized clinical trials are promising that combination oral regimens may play a role in antimicrobial management of complicated Gram-positive BSI, including infective endocarditis, septic arthritis and osteomyelitis. Whereas oral fluoroquinolones have been used successfully for decades in both uncomplicated and complicated Gram-negative BSI, recent studies suggest that trimethoprim-sulfamethoxazole and aminopenicillins represent alternative oral options in uncomplicated Enterobacteriaceae BSI. Oral azoles have been used for definitive therapy of Candida species BSI and are currently recommended by the international management guidelines.ImplicationsRecent studies demonstrate that early transition from intravenous to oral therapy is a feasible and effective strategy in most patients with BSI due to Gram-negative bacteria, obligate anaerobic bacteria and Candida species. Oral antimicrobial combinations may be considered in select patients with complicated Gram-positive BSI after 10–14 days of intravenous therapy. Future studies will determine the role of oral agents for switch therapy in uncomplicated Gram-positive BSI.     

Follow-up blood cultures are associated with improved outcome of patients with gram-negative bloodstream infections: retrospective observational cohort study

ObjectivesWe examined factors associated with follow-up blood cultures (FUBCs) in patients with monomicrobial Gram-negative (GN) bloodstream infection (BSI) and investigated the impact of FUBCs on therapeutic management and patient outcome.MethodsA retrospective cohort analysis was conducted of adult patients diagnosed with GN-BSI at a tertiary-care university hospital during 2013–2016. FUBCs performed between 24 hours and 7 days after index BCs was the exposure variable. Risk factors for 30-day mortality were analysed by multivariate Cox analysis on the overall cohort, including FUBCs as a time-varying covariate and on 1:1 matched patients according to Sequential Organ Failure Assessment (SOFA) score and time to FUBC.ResultsIn 278 (17.6%) of 1576 patients, FUBCs were performed within a median of 3 and 2 days after index BCs and active antibiotic therapy initiation. Persistent BSI was found in 107 (38.5%) of 278 patients. FUBCs were performed in more severely ill patients, with nonurinary sources, difficult-to-treat pathogens and receipt of initial inappropriate therapy. Source control and infectious disease consultation rates were higher among patients with preceding FUBCs and was associated with longer treatment duration. Thirty-day mortality was 10.4%. Independent risk factors for mortality were Charlson comorbidity index (hazard ratio (HR) 1.12) SOFA (HR 1.11), septic shock (HR 2.64), urinary source (HR 0.60), central venous catheter source (HR 2.30), complicated BSI (HR 2.10), carbapenem resistance (HR 2.34), active empiric therapy (HR 0.68), source control (HR 0.34) and FUBCs (HR 0.48). Association between FUBCs and lower mortality was confirmed in the 274 matched pairs.ConclusionsFUBCs were performed in more severe GN-BSIs, yielding a high rate of persistent BSI. In this context, FUBCs were associated with lower mortality.     

Antibiotic strategies and clinical outcomes in critically ill patients with pneumonia caused by carbapenem-resistant Acinetobacter baumannii

ObjectivesThis study aimed to investigate antibiotic prescribing patterns and effectiveness of different anti-carbapenem-resistant Acinetobacter baumannii (CRAB) strategies for CRAB pneumonia.MethodsWe conducted a multicentre, retrospective study in three hospitals. During 2010–2015, adult ICU patients with CRAB pneumonia treated with at least one antimicrobial agent covering the CRAB isolate in vitro for more than 2 days were included. We used multivariate logistic regression to analyse the associations of anti-CRAB strategies with ICU mortality and other clinical outcomes.ResultsAmong 238 patients with CRAB pneumonia, tigecycline monotherapy (84, 35.3%) was the most common antibiotic strategy, followed by tigecycline with colistin (43, 18.1%), colistin monotherapy (34, 14.3%), colistin combination without tigecycline (33, 13.9%), tigecycline combination without colistin (32, 13.4%), and sulbactam-based therapy without tigecycline and colistin (12, 5.0%). In multivariate analysis, tigecycline-based therapy was associated with higher ICU mortality than non-tigecycline therapy (adjusted OR 2.30, 95% CI 1.19–4.46). There was no difference between colistin-based therapy and non-colistin therapy. Compared with tigecycline monotherapy, colistin monotherapy was associated with lower ICU mortality (aOR 0.30, 95% CI 0.10–0.88). Treatment failure analyses showed similar trends. Tigecycline-based therapy was associated with higher treatment failure rate than non-tigecycline therapy (aOR 2.51, 95% CI 1.39–4.54), whereas colistin-based therapy was associated with lower treatment failure rate than non-colistin-based therapy (aOR 0.48, 95% CI 0.27–0.86).ConclusionsTigecycline was commonly prescribed for CRAB pneumonia. However, tigecycline-based therapy was associated with higher ICU mortality and treatment failure. Our study suggests that colistin monotherapy may be a better antibiotic strategy for CRAB pneumonia.     

Outcomes of corticosteroid treatment in critical Ill adult patients with respiratory viruses-related community acquired pneumonia – a propensity-matched case control study

ObjectivesTo assess the outcomes of corticosteroid treatment in critically ill patients with respiratory virus–related community-acquired pneumonia (CAP).Materials/methodsAdult patients who were admitted to the intensive care unit and had a polymerase chain reaction–confirmed diagnosis of respiratory virus–related CAP were included. Patients with and without corticosteroid treatment during the hospital course were retrospectively compared using a propensity score–matched case–control analysis.ResultsFrom January 2018 to December 2020, 194 adult patients were enrolled with 1:1 matching. The 14-day and 28-day mortality rates did not differ significantly between patients treated with and without corticosteroids (14-day mortality: 7% versus 14%, P = 0.11; 28-day mortality: 15% versus 20%, P = 0.35). However, multivariate analysis by using a Cox regression model revealed that corticosteroid treatment was an independent factor predicting decreased mortality (adjusted odds ratio, 0.46; 95% confidence interval, 0.22–0.97, P = 0.04). Subgroup analysis revealed lower 14-day and 28-day mortality rates in patients younger than 70 years treated with corticosteroids than in those not treated with corticosteroids (14-day mortality: 6% versus 23%; P = 0.01 and 28-day mortality: 12% versus 27%; P = 0.04).ConclusionsNon-elderly patients with severe respiratory virus–related CAP are more likely to benefit from corticosteroid treatment than elderly patients.     

Factors associated with mortality in patients with bloodstream infection and pneumonia due to Stenotrophomonas maltophilia

Severe infections caused by Stenotrophomonas maltophilia are associated with high mortality, and strategies to improve the clinical outcome for infected patients are needed. A retrospective cohort study of patients with bloodstream infection (BSIs) and pneumonia caused by S. maltophilia was conducted. Multivariate analysis was performed to access factors associated with 14-day mortality. A total of 60 infections were identified. Among these, eight (13%) were pneumonias and 52 were BSIs; 33.3% were primary, 13% were central venous catheter (CVC)-related and 40% were secondary BSIs. Fifty-seven (85%) patients had received previous antimicrobial therapy; 88% had CVC, 57% mechanical ventilation and 75% were in the intensive care unit at the onset of infection. Malignancy (45%) was the most frequent underlying disease. The mean of the Acute Physiology and Chronic Health Evaluation II (APACHE II) scores was 17 and for the Sepsis-related Organ Failure Assessment (SOFA) score, it was 7 points. The overall and 14-day mortality were, respectively, 75% and 48%. Forty-seven (78%) patients were treated and, of these, 74% received trimethoprim-sulfamethoxazole. Independent risk factors associated with mortality were SOFA index >6 points (0.005) and septic shock (0.03). The Kaplan-Meier estimations curves showed that patients with APACHE II score >20 and SOFA score >10 had a survival chance of, respectively, less than 8% and less than 10% (P≤0.001) at 21 days after the first positive S. maltophilia culture. Our results suggest that the independent factors associated with outcome in patients with infection caused by S. maltophilia are septic shock and higher SOFA index.     

Development of a combination antibiogram for empirical treatments of Pseudomonas aeruginosa at a university-affiliated teaching hospital

IntroductionThe significantly higher mortality rate in the critical illness patients with Pseudomonas aeruginosa (PA) infection is linked to inappropriate selecting of empirical treatment. Traditional local antibiogram provides clinicians the resistant rate of a single antimicrobial agent to the pathogen in the specific setting. The information is valuable to the clinicians in selecting suitable empirical antibiotic therapy. However, traditional local antibiogram can only provide information for single agent empirical antibiotic not combination regimens. The combination antibiogram should be developed to facilitate the selection of appropriate antibiotics to broader the coverage rate of resistant PA.MethodsThe susceptibility to the β-lactam antibiotics (piperacillin/tazobactam (PTZ), ceftazidime, cefepime, imipenem, or meropenem) or to those administered in combination with an aminoglycoside (gentamicin or amikacin) or fluoroquinolone (ciprofloxacin or levofloxacin) was calculated. The chi-square test was used to compare the differences of combination coverage rates between non-ICU and ICU isolates.Results880 PA isolates were isolated during study period. The susceptibility of single agents ranged from 83.1% to 89.7%. The combination regimens containing amikacin provide the highest cover rate (98.9%–99.1%) and those containing levofloxacin provide less coverage rate (92.3%–93.9%). The susceptibility to five β-lactam single agents in ICU isolates significantly lower than non-ICU isolates. The non-ICU isolates exhibited significantly higher susceptibility to the PTZ–gentamicin (p = 0.002) and ceftazidime–gentamicin (p = 0.025) than ICU isolates.ConclusionOur results support the use of aminoglycosides instead of fluoroquinolones as additive agents in empirical combination treatments for patients with critical infections caused by PA.     

Comparison of colistin–carbapenem,colistin–sulbactam,and colistin plus other antibacterial agents for the treatment of extremely drug-resistant Acinetobacter baumannii bloodstream infections

The purpose of this investigation was to compare the efficacy of colistin-based therapies in extremely drug-resistant Acinetobacter spp. bloodstream infections (XDR-ABSI). A retrospective study was conducted in 27 tertiary-care centers from January 2009 to August 2012. The primary end-point was 14-day survival, and the secondary end-points were clinical and microbiological outcomes. Thirty-six and 214 patients [102 (47.7 %): colistin–carbapenem (CC), 69 (32.2 %): colistin–sulbactam (CS), and 43 (20.1 %: tigecycline): colistin with other agent (CO)] received colistin monotherapy and colistin-based combinations, respectively. Rates of complete response/cure and 14-day survival were relatively higher, and microbiological eradication was significantly higher in the combination group. Also, the in-hospital mortality rate was significantly lower in the combination group. No significant difference was found in the clinical (p?=?0.97) and microbiological (p?=?0.92) outcomes and 14-day survival rates (p?=?0.79) between the three combination groups. Neither the timing of initial effective treatment nor the presence of any concomitant infection was significant between the three groups (p?>?0.05) and also for 14-day survival (p?>?0.05). Higher Pitt bacteremia score (PBS), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, Charlson comorbidity index (CCI), and prolonged hospital and intensive care unit (ICU) stay before XDR-ABSI were significant risk factors for 14-day mortality (p?=?0.02, p?=?0.0001, p?=?0.0001, p?=?0.02, and p?=?0.01, respectively). In the multivariable analysis, PBS, age, and duration of ICU stay were independent risk factors for 14-day mortality (p?<?0.0001, p?<?0.0001, and p?=?0.001, respectively). Colistin-based combination therapy resulted in significantly higher microbiological eradication rates, relatively higher cure and 14-day survival rates, and lower in-hospital mortality compared to colistin monotherapy. CC, CS, and CO combinations for XDR-ABSI did not reveal significant differences with respect to 14-day survival and clinical or microbiological outcome before and after propensity score matching (PSM). PBS, age, and length of ICU stay were independent risk factors for 14-day mortality.