Predictors of fatality in influenza A virus subtype infections among inpatients in the 2015-2016 season.

BACKGROUND: Infection with the influenza A virus can cause severe disease and mortality. The effect of the different subtypes of influenza on morbidity and mortality is not yet known in Turkey. The aim of this study was to describe the predictors of fatality related to influenza A infection among hospitalized patients in Istanbul during the 2015-2016 influenza season, and to detail the differences between infections caused by H3N2 and H1N1. METHODS: This was a multicenter study performed by the Istanbul Respiratory Infections Study Group of The Turkish Society of Clinical Microbiology and Infectious Diseases (KLIMIK), among patients hospitalized for influenza in Istanbul during the 2015-2016 influenza season. RESULTS: A total of 222 patients hospitalized with laboratory-confirmed influenza during the 2015-2016 season were included in the study, of whom 25 (11.2%) died. The fatality rate was significantly higher among patients older than 65 years of age and those with chronic heart and kidney diseases (p<0.001), chronic neurological diseases (p=0.009), and malignancies (p=0.021). Thrombocyte counts were lower in those who died than in those who survived (p<0.004). The median alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, creatinine phosphokinase, and C-reactive protein levels were higher among fatal cases. In the multivariate analysis for the prediction of fatality, being >65years old (odds ratio (OR) 6.9, 95% confidence interval (CI) 2.07-23.08, p=0.002), being infected with influenza A(H3N2) (OR 4.2, 95% CI 1.27-14.38, p=0.019), and a 1-day delay in antiviral use (OR 1.28, 95% CI 1.01-1.63, p=0.036) were found to be associated with an increased likelihood of fatality. CONCLUSIONS: The case fatality rate of influenza A(H3N2) was significantly higher than that of influenza A(H1N1). Detection of the infection, allowing the opportunity for the early use of antiviral agents, was found to be important for the prevention of fatality. The vaccination should be prioritized for at-risk groups.

Rumen bacteria at work: bioaugmentation strategies to enhance biogas production from cow manure.

AIMS: To investigate the effects of different bioaugmentation strategies for enhancing the biogas production from cow manure and evaluate microbial community patterns. METHODS AND RESULTS: Co-inoculation with cow rumen fluid and cow rumen-derived enriched microbial consortia was evaluated in anaerobic batch tests at 36°C and 41°C. Singular addition of both rumen fluid and enriched bioaugmentation culture had a promising enhancement on methane yields; however, the highest methane yield (311 ml CH4 per gram VS at 41°C) was achieved when the anaerobic seed sludge was co-inoculated together with rumen fluid and enriched bioaugmentation culture. Bacterial community profiles were investigated by Ion PGM Platform, and specific lignocellulolytic bacteria dynamics in batch tests were assessed by qPCR. The temperature had minor effects on the abundance of bacterial community; in which Bacteroidetes and Firmicutes were the most abundant phyla in all digesters. Furthermore, Rikenellaceae, Clostridiaceae, Porphyromonadaceae, Bacteroidaceae and Ruminococcaceae played a crucial role during the anaerobic degradation of cow manure. There was an important impact of Firmicutes flavefaciens and Ruminococcus albus at 41°C, which in turn positively affected the methane production. CONCLUSION: The degree of enhancement in biogas production can be upgraded by the co-inoculation of rumen-derived bioaugmentation culture with anaerobic seed sludge with high methanogenic activity. SIGNIFICANCE AND IMPACT OF THE STUDY: A close look at the biotic interactions and their associations with abiotic factors might be valuable for evaluating rumen-related bioaugmentation applications.

Rapid emergence of colistin resistance and its impact on fatality among healthcare-associated infections.

This article describes the emergence of resistance and predictors of fatality for 1556 cases of healthcare-associated Gram-negative bloodstream infection in 2014 and 2015. The colistin resistance rate in Klebsiella pneumoniae was 16.1%, compared with 6% in 2013. In total, 660 (42.4%) cases were fatal. The highest fatality rate was among patients with Acinetobacter baumannii bacteraemia (58%), followed by Pseudomonas aeruginosa (45%), Klebsiella pneumoniae (41%), Enterobacter cloacae (32%) and Escherichia coli (28%). On multi-variate analysis, the minimum inhibitory concentrations for carbapenems [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.01-1.04; P = 0.002] and colistin (OR 1.1, 95% CI 1.03-1.17; P = 0.001) were found to be significantly associated with fatality.

Risk factors for mortality in patients with nosocomial Gram-negative rod bacteremia.

BACKGROUND: The percentage of hospital-acquired bloodstream infections associated with Gram-negative bacilles has decreased during last decade but it is still a major cause of morbidity and mortality. OBJECTIVES: The aim of this study was to determine the outcome of Gram-negative rod (GNR) bacteremia, which is an important clinical problem with high mortality rates, and the risk factors for GNR related mortality in our Clinic. MATERIALS AND METHODS: During the study period, 520 episodes of bacteremia were detected in 411 patients. Only patients with GNR bacteremia in blood cultures were included in the study (n = 197). Among 197 patients fulfilling study criteria, GNR were grown in 239 samples. RESULTS: Escherichia coli (n = 97, 40.5%), Klebsiella pneumoniae (n = 54, 22.5%), Pseudomonas aeruginosa (n= 24, 10%), Acinetobacter baumannii (n = 24, 10%) were the most commonly isolated bacteria. The most frequently identified infection sources of bacteremia were pneumonia (n = 35, 17.7%), catheter-related infections (n = 24, 12.2%), urinary tract infections (n = 20, 10%). In multivariate analysis, it was found that the GNR bacteremia mortality risk increased in patients treated in intensive care units (ICU) (OR: 0.2, p = 0.03) and patients with ventilatory support (OR: 20.8, p = 0.05). CONCLUSIONS: In clinical practice of the hospital settings, efforts should concentrate on preventive measures for nosocomial infections since pneumonia, catheter-related infections, and urinary infections appear to be the most frequent causes of secondary bacteremia.