Multidrug Resistant Acinetobacter baumannii: Risk Factors for Appearance of Imipenem Resistant Strains on Patients Formerly with Susceptible Strains

BACKGROUND: Multidrug resistant Acinetobacter baumannii (MDRAB) is an important nosocomial pathogen usually susceptible to carbapenems; however, growing number of imipenem resistant MDRAB (IR-MDRAB) poses further clinical challenge. The study was designed to identify the risk factors for appearance of IR-MDRAB on patients formerly with imipenem susceptible MDRAB (IS-MDRAB) and the impact on clinical outcomes. METHODOLOGY/PRINCIPAL FINDINGS: A retrospective case control study was carried out for 209 consecutive episodes of IS-MDRAB infection or colonization from August 2001 to March 2005. Forty-nine (23.4%) episodes with succeeding clinical isolates of IR-MDRAB were defined as the cases and 160 (76.6%) with all subsequent clinical isolates of IS-MDRAB were defined as the controls. Quantified antimicrobial selective pressure, "time at risk", severity of illness, comorbidity, and demographic data were incorporated for multivariate analysis, which revealed imipenem or meropenem as the only significant independent risk factor for the appearance of IR-MDRAB (adjusted OR, 1.18; 95% CI, 1.09 to 1.27). With selected cases and controls matched to exclude exogenous source of IR-MDRAB, multivariate analysis still identified carbapenem as the only independent risk factor (adjusted OR, 1.48; 95% CI, 1.14 to 1.92). Case patients had a higher crude mortality rate compared to control patients (57.1% vs. 31.3%, p = 0.001), and the mortality of case patients was associated with shorter duration of "time at risk", i.e., faster appearance of IR-MDRAB (adjusted OR, 0.9; 95% CI, 0.83 to 0.98). CONCLUSIONS/SIGNIFICANCE: Judicious use of carbapenem with deployment of antibiotics stewardship measures is critical for reducing IR-MDRAB and the associated unfavorable outcome

Syndromic Recognition of Influenza A Infection in a Low Prevalence Community Setting

BACKGROUND: With epidemics of influenza A virus infection, people and medical professionals are all concerned about symptoms or syndromes that may indicate the infection with influenza A virus. METHODOLOGY/PRINCIPAL FINDINGS: A prospective study was performed at a community clinic of a metropolitan area. Throat swab was sampled for 3-6 consecutive adult patients with new episode (<3 days) of respiratory tract infection every weekday from Dec. 8, 2005 to Mar. 31, 2006. Demographic data, relevant history, symptoms and signs were recorded. Samples were processed with multiplex real time PCR for 9 common respiratory tract pathogens and by virus culture. Throat swab samples were positive for Influenza A virus with multiplex real time PCR system in 12 of 240 patients. The 12 influenza A positive cases were with more clusters and chills than the other 228. Certain symptoms and syndromes increased the likelihood of influenza A virus infection. The syndrome of high fever plus chills plus cough, better with clustering of cases in household or workplace, is with the highest likelihood (positive likelihood ratio 95; 95% CI 12-750). Absence of both cluster and chills provides moderate evidence against the infection (negative likelihood ratio 0.51; 95% CI 0.29-0.90). CONCLUSIONS/SIGNIFICANCE: Syndromic recognition is not diagnostic but is useful for discriminating between influenza A infection and common cold. In addition to relevant travel history, confirmatory molecular test can be applied to subjects with high likelihood when the disease prevalence is low

Clinical characteristics of acute hepatitis A outbreak in Taiwan, 2015–2016: observations from a tertiary medical center

Abstract Background Acute hepatitis A is a fecal-oral transmitted disease related to inadequate sanitary conditions. In addition to its traditional classification, several outbreaks in the men who have sex with men (MSM) population have resulted in acute hepatitis A being recognized as a sexually transmitted disease. However, few studies have clarified the clinical manifestations in these outbreaks involving the MSM population. Methods Beginning in June 2015, there was an outbreak of acute hepatitis A involving the MSM population in Northern Taiwan. We conducted a 15-year retrospective study by recruiting 207 patients with the diagnosis of acute hepatitis A that included the pre-outbreak (January 2001 to May 2015) and outbreak (June 2015 to August 2016) periods in a tertiary medical center in Northern Taiwan. Using risk factors, comorbidities, presenting symptoms, laboratory test results and imaging data, we aimed to evaluate the clinical significance of acute hepatitis A in the MSM population, where human immunodeficiency virus (HIV) coinfection is common. Results There was a higher prevalence of reported MSM (p < 0.001), HIV (p < 0.001) and recent syphilis (p < 0.05) coinfection with acute hepatitis A during the outbreak period. The outbreak population had more prominent systemic symptoms, was more icteric with a higher total bilirubin level (p < 0.05) and had a 7-times higher tendency (p < 0.05) to have a hepatitis A relapse. Conclusions The clinical course of acute hepatitis A during an outbreak involving the MSM and HIV-positive population is more symptomatic and protracted than in the general population

Additional file 1: of Clinical characteristics of acute hepatitis A outbreak in Taiwan, 2015–2016: observations from a tertiary medical center

Supplementary materials. The clinical information of the excluded cases and causes of mortality in this study are included in the supplementary material. (DOCX 17 kb

Clinical characteristics and treatment outcomes of vancomycin-resistant Enterococcus faecium bacteremia

Background: Vancomycin-resistant Enterococcus faecium (VRE-fm) bacteremia causes significant mortality in hospitalized patients. We sought to investigate clinical characteristics, treatment outcomes, and microbiological eradication associated with VRE-fm bacteremia. Methods: A retrospective cohort study was conducted and included 210 adult patients admitted between January 1, 2011 and December 31, 2015. Results: The mean Pitt bacteremia score was 4.7. ICU stay (48.6%) and mechanical ventilation (46.2%) were common. Diabetes mellitus was the most common concomitant disease (43.3%), followed by malignancies, including hematologic malignancies (14.3%) and solid cancers (28.1%). The 14-day and 28-day mortality rates were 37.1% and 50.5%, respectively. Linezolid or daptomycin treatment for at least 10 days and higher Pitt bacteremia scores were independently associated with 14-day and 28-day mortality. Longer treatment duration of linezolid or daptomycin predicted microbiological eradication independently. Daptomycin-treated patients tended to have higher 14-day and 28-day mortality, and lower microbial eradication rates (20.8% versus 8.7%; 40.6% versus 26.1%; 14.1% versus 26.1%; respectively) than linezolid-treated patients, and cumulative survival rates at 14 and 28 days tended to be lower in patients who received low-dose daptomycin (<10 mg/kg/day) than that in those who received linezolid and high-dose daptomycin (≥10 mg/kg/day); however, the differences were not statistically significant. Conclusion: Higher disease severity and inappropriate treatment were associated with increased mortality and longer treatment duration of linezolid or daptomycin was associated with microbial eradication for the patient with VRE-fm bacteremia. Keywords: Vancomycin-resistant, Enterococcus faecium, Bacteremia, Daptomycin, Linezoli

Case Report of Low Virulence Francisella tularensis Presented as Severe Bacteremic Pneumonia

BackgroundForced alcohol (ethanol, EtOH) exposure has been shown to cause significant impairments on reversal learning, a widely-used assay of cognitive flexibility, specifically on fully-predictive, deterministic versions of this task. However, previous studies have not adequately considered voluntary EtOH consumption and sex effects on probabilistic reversal learning. The present study aimed to fill this gap in the literature.MethodsMale and female Long-Evans rats underwent either 10 weeks of voluntary intermittent 20% EtOH access or water only (H2O) access. Rats were then pretrained to initiate trials and learn stimulus-reward associations via touchscreen response, and subsequently required to select between two visual stimuli, rewarded with probability 0.70 or 0.30. In the final phase, reinforcement contingencies were reversed.ResultsWe found significant sex differences on several EtOH-drinking variables, with females reaching a higher maximum EtOH consumption, exhibiting more high-drinking days, and escalating their EtOH at a quicker rate compared to males. During early abstinence, EtOH drinkers (and particularly EtOH-drinking females) made more initiation omissions and were slower to initiate trials than H2O drinking controls, especially during pretraining. A similar pattern in trial initiations was also observed in discrimination, but not in reversal learning. EtOH drinking rats were unaffected in their reward collection and stimulus response times, indicating intact motivation and motor responding. Although there were sex differences in discrimination and reversal phases, performance improved over time. We also observed sex-independent drinking group differences in win-stay and lose-shift strategies specific to the reversal phase.ConclusionsFemales exhibit increased vulnerability to EtOH effects in early learning: there were sex-dependent EtOH effects on attentional measures during pretraining and discrimination phases. We also found sex-independent EtOH effects on exploration strategies during reversal. Future studies should aim to uncover the neural mechanisms for changes in attention and exploration in both acute and prolonged EtOH withdrawal

Acquisition and clearance of multidrug resistant Acinetobacter baumannii on healthy young adults concurrently burned in a dust explosion in Taiwan: the implication for antimicrobial stewardship

Abstract Background Information is limited about the effect of restricted carbapenem use on clearance of multi-drug resistant Acinetobacter baumannii (MDRAB). We sought to determine the time effect of antibiotic exposure on multi-drug resistant Acinetobacter baumannii (MDRAB) acquisition and clearance. Methods We conducted a retrospective observational study at the intensive care units of a tertiary medical center. Forty-two of a cohort of previously healthy young adults who were concurrently burned by a dust explosion was included. Cases consisted of those from whom MDRAB was isolated during hospitalization. Controls consisted of patients from whom MDRAB was not isolated in the same period. Use of antimicrobial agents was compared based on days of therapy per 1,000 patient-days (DOT/1,000PD). A 2-state Markov multi-state model was used to estimate the risk of acquisition and clearance of MDRAB. Results MDRAB was discovered in 9/42 (21.4%) individuals. The cases had significantly higher use of carbapenem (652 DOT/1,000PD vs. 385 DOT/1,000PD, P < 0.001) before MDRAB isolation. For the cases, clearance of MDRAB was associated with lower use of carbapenem (469 DOT/1,000PD vs. 708 DOT/1,000PD, P = 0.003) and higher use of non-carbapenem beta-lactam (612 DOT/1,000PD vs. 246 DOT/1,000PD, P <0.001). In multi-state model, each additional DOT of carbapenem increased the hazard of acquiring MDRAB (hazard ratio (HR), 1.08; 95% confidence interval (CI) 1.01–1.16) and each additional DOT of non-carbapenem beta-lactam increased the protection of clearing MDRAB (HR, 1.25; 95% CI 1.07–1.46). Conclusions Both acquisition and clearance of MDRAB were related to antibiotic exposure in a homogeneous population. Our findings suggest that early discontinuation of carbapenem could be an effective measure in antibiotic stewardship for the control of MDRAB spreading

Univariate and multivariate analyses of risk factors for appearance of IR-MDRAB.

<p>NOTE. ^aCategorical data are no.(%) of subject, continuous data are expressed as mean (SD) or median [quartiles].</p>b<p>All variables included in the final multivariable model are shown.</p>c<p>Only significant (<i>p</i><0.05) and selected non-significant variables in univariate analysis are shown.</p><p>OR  =  odds ratio; CI  =  confidence interval; TAR  =  time at risk; ICU  =  intensive care unit; APACHE II  =  Acute Physiology and Chronic Health Evaluation II; SD  =  standard deviation.</p

Matched univariate and multivariate analyses of risk factors for appearance of IR-MDRAB.

<p>NOTE. ^a Categorical data are no.(%) of subject, continuous data are expressed as mean (SD) or median [quartiles].</p>b<p>All variables included in the final multivariable model are shown.</p>c<p>Only significant (<i>p</i><0.05) and selected non-significant variables in univariate analysis are shown.</p><p>OR  =  odds ratio; CI  =  confidence interval; TAR  =  time at risk; ICU  =  intensive care unit; APACHE II  =  Acute Physiology and Chronic Health Evaluation II; SD  =  standard deviation.</p