Chia Wen Li

Cefepime Therapy for Monomicrobial Enterobacter cloacae Bacteremia: Unfavorable Outcomes in Patients Infected by Cefepime-Susceptible Dose-Dependent Isolates

ABSTRACT A new category of cefepime susceptibility, susceptible dose dependent (SDD), for Enterobacteriaceae, has been suggested to maximize its clinical use. However, clinical evidence supporting such a therapeutic strategy is limited. A retrospective study of 305 adults with monomicrobial Enterobacter cloacae bacteremia at a medical center from 2008 to 2012 was conducted. The patients definitively treated with in vitro active cefepime (cases) were compared with those treated with a carbapenem (controls) to assess therapeutic effectiveness. The 30-day crude mortality rate is the primary endpoint, and clinical prognostic factors are assessed. Of 144 patients receiving definitive cefepime or carbapenem therapy, there were no significant differences in terms of age, sex, comorbidity, source of bacteremia, disease severity, or 30-day mortality (26.4% versus 22.2%; P = 0.7) among those treated with cefepime (n = 72) or a carbapenem (n = 72). In the multivariate analysis, the presence of critical illness, rapidly fatal underlying disease, extended-spectrum beta-lactamase (ESBL) producers, and cefepime-SDD (cefepime MIC, 4 to 8 μg/ml) isolates was independently associated with 30-day mortality. Moreover, those infected by cefepime-SDD isolates with definitive cefepime therapy had a higher mortality rate than those treated with a carbapenem (5/7 [71.4%], versus 2/11 [18.2%]; P = 0.045). Cefepime is one of the therapeutic alternatives for cefepime-susceptible E. cloacae bacteremia but is inefficient for cases of cefepime-SDD E. cloacae bacteremia compared with carbapenem therapy.

Clinical impact of Gram-negative nonfermenters on adults with community-onset bacteremia in the emergency department

BACKGROUNDnTo determine clinical predictors and impact of Gram-negative nonfermenters (GNNFs) infections among adults with community-onset bacteremia in the emergency department (ED).nnnMETHODSnAdults with bacteremia visiting the ED from January 2007 to June 2008 were identified retrospectively. Demographic characteristics, underlying illnesses, clinical conditions, bacteremic pathogens, antimicrobial agents, and outcome, were retrieved from chart records.nnnRESULTSnAfter the exclusion of 261 patients with contamination of blood cultures and 24 patients referred from other hospitals, 518 adults with community-onset bacteremia were eligible; their mean age was 65.1 years, with slight predominance of female (262 patients, 50.6%). Of a total of 565 bacteremic isolates, Escherichia coli (228 isolates, 40.4%) and Klebsiella pneumoniae (100, 17.7%) were the major microorganisms. GNNFs caused bacteremia in 31 (6.0%) patients. A higher proportion of inappropriate antibiotic therapy in the ED (87.1% vs. 26.5%, p < 0.001) and higher 28-day crude mortality rate (19.4% vs. 8.4%, p = 0.05) were observed in bacteremic patients caused by GNNFs than those not caused by GNNFs. In further analysis of Kaplan-Meier survival curve, patients with GNNF bacteremia had a worse outcome than those due to other pathogens (p = 0.04). Multivariate analysis revealed that the independent predictors related to GNNF bacteremia included surgery during previous 4 weeks prior to ED arrival [odds ratio (OR), 10.79; 95% confidence interval (CI), 1.84-63.24; p = 0.01], residents in long-term healthcare facilities (OR, 4.62; 95% CI, 2.08-10.29; p < 0.001), and malignancy (OR, 2.24; 95% CI, 1.10-5.40; p = 0.02).nnnCONCLUSIONnFor adults with bacteremia visiting the ED, GNNF is associated with a higher mortality rate and more inappropriate empirical antibiotic therapy in the ED. To allow early administration of empirical antibiotics, several clinical predictors of GNNF infections were identified.

Virulence diversity among bacteremic aeromonas isolates: Ex vivo, animal, and clinical evidences

Background The objective of this study was to compare virulence among different Aeromonas species causing bloodstream infections. Methodology/Principal Findings Nine of four species of Aeromonas blood isolates, including A. dhakensis, A. hydrophila, A. veronii and A. caviae were randomly selected for analysis. The species was identified by the DNA sequence matching of rpoD. Clinically, the patients with A. dhakensis bacteremia had a higher sepsis-related mortality rate than those with other species (37.5% vs. 0%, Pu200a=u200a0.028). Virulence of different Aeromonas species were tested in C. elegans, mouse fibroblast C2C12 cell line and BALB/c mice models. C. elegans fed with A. dhakensis and A. caviae had the lowest and highest survival rates compared with other species, respectively (all P values <0.0001). A. dhakensis isolates also exhibited more cytotoxicity in C2C12 cell line (all P values <0.0001). Fourteen-day survival rate of mice intramuscularly inoculated with A. dhakensis was lower than that of other species (all P values <0.0001). Hemolytic activity and several virulence factor genes were rarely detected in the A. caviae isolates. Conclusions/Significance Clinical data, ex vivo experiments, and animal studies suggest there is virulence variation among clinically important Aeromonas species.

Non-typhoidal Salmonella bacteremia among adults: An adverse prognosis in patients with malignancy

BACKGROUNDnClinical information about non-typhoidal Salmonella (NTS) bacteremia in patients with malignancy has rarely been described. This study investigated clinical characteristics and prognostic variables of patients with malignancy while complicated with NTS bacteremia.nnnMETHODSnThe study included demographic data, clinical information, and outcome in adults (≥18 years old) with and without malignancy complicated with NTS bacteremia at a medical center from 2000 to 2009.nnnRESULTSnThere were 206 patients with NTS bacteremia. The serogroups of NTS isolates included group B (40.2%), group D (30.9%), group C (26.5%), and group E (1.5%). Extraintestinal infections were noted in 66 (32.4%) patients and were mainly endovascular (26/206, 12.7%) or pleuropulmonary (17/206, 8.3%) infections. On multivariate analysis, independent factors for in-hospital mortality included shock (odds ratio [OR] 9.13; 95% confidence interval [CI] 3.81-21.83; pxa0<xa00.001), malignancy (OR 8.42; 95% CI 3.12-22.71; pxa0<xa00.001), and acute renal failure (OR 2.63; 95% CI 1.11-6.22; pxa0=xa00.028). Different clinical presentations and outcome were noted in 74 (36.2%) patients with malignancy and 130 without malignancy. The former had more leucopenia and thrombocytopenia at initial presentation and fewer extraintestinal infections (20.2% vs. 39.2%, pxa0=xa00.005), endovascular infections (2.7% vs. 18.5%; pxa0=xa00.002), and serovar Choleraesuis (10.8% vs. 27.7%; pxa0=xa00.005). An elevated in-hospital mortality rate was noted in patients with malignancy compared to those without malignancy (40.5% vs. 17.7%, pxa0<xa00.001). Among patients with malignancy, multivariate analysis revealed that shock was the only independent factor associated with in-hospital mortality (OR 7.52; 95% CI, 2.38-23.80; pxa0=xa00.001).nnnCONCLUSIONnMalignancy is an adverse prognostic factor in patients with NTS bacteremia. Food safety in patients with malignancy should be emphasized to prevent salmonellosis.

Bacteremic pneumonia caused by extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae: Appropriateness of empirical treatment matters

BACKGROUNDnClinical information about bacteremic pneumonia caused by extended-spectrum beta-lactamase (ESBL)-producing organism is limited.nnnMETHODSnA retrospective study was conducted at two medical centers in Taiwan. From May 2002 to August 2010, clinical information and outcome of adults with bacteremic pneumonia caused by ESBL-producing Escherichia coli and Klebsiella pneumoniae were analyzed. The primary outcome is the 30-day mortality.nnnRESULTSnA total of 111 patients with bacteremic pneumonia caused by E. coli (37 patients, 33.3%) and K. pneumoniae (74, 66.7%) were identified. Their mean age was 69.2 years and 51.4% were male patients. Fifty-seven (51.3%) episodes were classified as hospital-acquired infections, 19 (17.1%) as health-care-associated infections, and four (3.6%) as community-acquired infections. Fifty-one (45.9%) patients received appropriate empiric antimicrobial therapy. The 30-day mortality rate was 40.5% (45 patients). In the multivariate analysis, several independent risk factors, including rapidly fatal underlying disease [odds ratio (OR), 5.75; 95% confidence interval (CI), 1.54-21.48; p = 0.009], severe sepsis (OR, 4.84; 95% CI, 1.55-15.14; p = 0.007), critical illness (OR, 4.28; 95% CI, 1.35-13.57; p = 0.013), and receipt of appropriate empirical therapy (OR, 0.19; 95% CI, 0.07-0.55; p = 0.002), were associated with 30-day mortality. The survival analysis consistently found that individuals with appropriate empiric therapy had a higher survival rate (log-rank test, p < 0.001).nnnCONCLUSIONnESBL-producing bacteremic pneumonia, especially health-care-associated infections, often occurred in adults with comorbidities. Appropriate empirical therapy was associated with a favorable outcome.

Willingness to self-pay for pre-exposure prophylaxis in men who have sex with men: A national online survey in Taiwan

High cost of pre-exposure prophylaxis (PrEP) is a major concern for acceptability. This study determined the willingness of men who have sex with men to self-pay for PrEP and factors associated with the likelihood of condom use if taking PrEP. The Taiwan 2014 MSM Online Sex Survey was conducted and data such as demographics, attitudes toward PrEP, and sexual behaviors in the previous 3 months were collected. Of the 1,151 MSM who participated, 56% were willing to take PrEP, but only 23% were willing to self-pay

Aeromonas stool isolates from individuals with or without diarrhea in southern Taiwan: Predominance of Aeromonas veronii

340 for PrEP. Willingness to self-pay for PrEP was significantly associated with the previous receipt of nonoccupational post-exposure prophylaxis (adjusted odds ratio [AOR], 3.02, 95%CI [1.49, 6.12]), and positive attitudes toward PrEP (AOR, 3.02, 95%CI [2.19, 4.17]). Of MSM who are willing to use PrEP, 73.6% would maintain condom use if taking PrEP. If PrEP is made available in Taiwan, more efforts should be focused on increasing awareness of MSM who are practicing risky behaviors.

Time-to-positivity of blood culture: An independent prognostic factor of monomicrobial Pseudomonas aeruginosa bacteremia.

BACKGROUNDnAlthough aeromonads are important pathogens causing invasive infections in southern Taiwan, Aeromonas-associated intestinal infections have been rarely mentioned.nnnPURPOSEnThe aim of this study was to understand the frequency of isolation and clinical significance of aeromonads recovered from adult stool samples in southern Taiwan.nnnMETHODSnDuring a 15-month study period, 514 adults with diarrhea and 167 asymptomatic controls were prospectively screened for the presence of aeromonads in stools. The identity of Aeromonas species was determined by the rpoD sequencing. Clinical information was retrieved from medical records, and inxa0vitro cytotoxicity assay and polymerase chain reaction detection of putative virulent genes were performed.nnnRESULTSnThirteen (2.5 %) of 514 diarrheal patients and six (3.6%) of 167 asymptomatic controls had Aeromonas isolates in their stools. Of 11 diarrheal patients with available clinical information, Aeromonas veronii, the predominant species, was noted in six patients, and another potential enteropathogen was present in four patients. The cytotoxicity of A. veronii isolates to the HT-29 cell line was more potent in the isolates from diarrheal patients than those from asymptomatic controls (pxa0=xa00.015). The cytotoxicity of A. veronii isolates was more potent than that of A. caviae from symptomatic patients (pxa0=xa00.001). Putative virulence markers, including AHCYTONE, ascV, ascF-ascG, and aexT, were detected exclusively in A. veronii. The presence of the ascV gene was associated with cytotoxicity in A. veronii isolates. All Aeromonas isolates were susceptible to varied antimicrobial agents, except ampicillin/sulbactam.nnnCONCLUSIONnA. veronii is the predominant species in stools from individuals with or without diarrhea in southern Taiwan.

Salmonella infective endocarditis

BACKGROUND/PURPOSEnPseudomonas aeruginosa bacteremia is an important cause of nosocomial infections with high morbidity and mortality. Time-to-positivity (TTP) of blood cultures is considered to be a predictor of the clinical outcome for bacteremia. The aim of the study is to investigate the relationship between TTP and clinical outcomes in patients with monomicrobial P. aeruginosa bacteremia.nnnMETHODSnFrom January 2013 to June 2014, a retrospective cohort study was conducted in a 1200-bed tertiary care hospital. The cases of monomicrobial P. aeruginosa bacteremia were studied. TTP and clinical parameters were determined and analyzed.nnnRESULTSnIn 139 cases of P. aeruginosa bacteremia, TTP ≤ 13 hours was associated with higher Pitt bacteremia scores (5.3xa0±xa04.2 vs. 2.3xa0±xa02.8, pxa0<xa00.001), severe sepsis (66.1% vs. 35.0%, pxa0<xa00.001), higher 30-day mortality rate (54.2% vs. 15.0%, pxa0<xa00.001), longer hospitalization in the survivors (25.6xa0±xa048.5 days vs. 16.3xa0±xa015.3 days, pxa0=xa00.16), and more admission to intensive care unit (27.2% vs. 16.3%, pxa0=xa00.14). Risk factors for 30-day mortality in the univariate analysis included corticosteroid exposure, primary bacteremia, concurrent pneumonia, a high Pitt bacteremia score, severe sepsis, and TTP ≤ 13 hours. In the multivariate analysis, primary bacteremia, a pulmonary origin of bacteremia, severe sepsis, and TTP ≤ 13 hours were independent risk factors for 30-day mortality.nnnCONCLUSIONnIn cases of monomicrobial P. aeruginosa bacteremia, a short TTP (≤ 13 hours) provides prognostic information, in addition to clinical parameters.

Acrophialophora fusispora brain abscess in a patient with acquired immunodeficiency syndrome: a case report and review of the literature

OBJECTIVEnSalmonella endocarditis is so rarely reported that its clinical features, prognosis, and optimal treatment remain unclear. In this paper, we report a female with nontyphoid Salmonella endocarditis complicated with perivalvular abscess. We also review and summarize other cases reported in the English literature.nnnMETHODSnUsing the key words Salmonella, infective endocarditis, and mural endocarditis to search the PubMed database, we reviewed case reports on Salmonella endocarditis published between 1976 and 2014 and case series of infective endocarditis that included at least 500 cases.nnnRESULTSnSalmonella species were rare infective endocarditis pathogens. Among 16 large case series, they accounted for less than 0.01% and up to 2.9% of bacterial endocarditis cases. From 1976 to 2014, a total of 87 cases of typhoid and nontyphoid Salmonella endocarditis were reported, which included 42 cases in 1976-1984, 30 cases in 1986-2002, and 15 cases in 2003-2014. Men predominated among the cases (58.6%), and the mean age was approximately 50-60 years. The major affected valves were the mitral valves (33.3%). Mural endocarditis was common (26.4%). Perivalvular abscess was only reported in 10.5% (6 cases) of 57 cases. The overall mortality rate was 42.5% and decreased over time from 69.0% to 13.3% during the three study periods.nnnCONCLUSIONnSalmonella endocarditis, although rare, may cause purulent infections in the perivalvular area or myocardium and lead to substantial mortality.