Livestock dung rather than biochar enhances the anaerobic methane oxidation in grassland soils.

The terrestrial anaerobic methane oxidation (AOM) coupled with denitrification is considered to be an important link in the "cryptic cycle of methane". However, it remains uncertain how land use activity such as biochar and livestock dung amendments regulate the AOM in grassland. Here, we incubated soils with biochar and dung amendments in microcosms to monitor the AOM activity and quantified the maker genes of anaerobic methanotrophs and their potential syntrophs. Dung enhanced the AOM mediated by Candidatus Methylomirabilis oxyfera and stimulated denitrifying bacteria and anammox growths as well. The biochar amendment inhibited AOM due to the trapping of NO3- and NO2-. Our study raised the possibility that anthropogenic activity can regulate AOM through porosity alteration and substrate limitation.

Anaerobic oxidation of methane in terrestrial wetlands: The rate, identity and metabolism.

The recent discovery of anaerobic oxidation of methane (AOM) in freshwater ecosystems has caused a great interest in "cryptic methane cycle" in terrestrial ecosystems. Anaerobic methanotrophs appears widespread in wetland ecosystems, yet, the scope and mechanism of AOM in natural wetlands remain poorly understood. In this paper, we review the recent progress regarding the potential of AOM, the diversity and distribution, and the metabolism of anaerobic methanotrophs in wetland ecosystems. The potential of AOM determined through laboratory incubation or in situ isotopic labeling ranges from 1.4 to 704.0 nmol CH4·g-1 dry soil·d-1. It appears that the availability of electron acceptors is critical in driving different AOM in wetland soils. The environmental temperature and salinity exert a significant influence on AOM activity. Reversal methanogenesis and extracellular electron transfer are likely involved in the AOM process. In addition to anaerobic methanotrophic archaea, the direct involvement of methanogens in AOM is also probable. This review presented an overview of the rate, identity, and metabolisms to unravel the biogeochemical puzzle of AOM in wetland soils.

Updating cut-off values of severity scoring systems for community-acquired pneumonia to orchestrate more predictive accuracy.

Background: The assessment of severity is crucial in the management of community-acquired pneumonia (CAP). It remains unknown whether updating cut-off values of severity scoring systems orchestrate improvement in predictive accuracy.Methods: 3,212 patients with CAP were recruited to two observational prospective cohort studies. Three bettered scoring systems were derived from the corresponding well-established and extensively used pneumonia-specific severity scoring systems, i.e. pneumonia severity index, minor criteria and CURB-65 (confusion, urea >7 mmol/L, respiratory rate ≥30/min, low blood pressure, and age ≥65 years) score, with the updating cut-off values for tachypnea and low blood pressure. Cronbach α was employed to determine construct validity. Discrimination was valued by calculating the area under the receiver operating characteristic curve (AUROC) and net reclassification improvement (NRI).Results: Respiratory rate ≥22/min and systolic blood pressure ≤100 mm Hg were performed better than respiratory rate ≥30/min and hypotension for predicting mortality in the derivation cohort, respectively (AUROC, 0.823 vs 0.519, 0.688 vs 0.622; NRI, 0.61, 0.13). Bettered scoring systems orchestrated higher convergences, indicated by greater Cronbach α and more decrease in Cronbach α if the updating cut-off values were deleted. The six scoring systems agreed well with one another. Bettered- pneumonia severity index, minor criteria and CURB-65 score showed higher associations with severity and mortality rates and demonstrated greater predictive accuracies for mortality compared with the corresponding original systems (AUROC, 0.939 vs 0.883, 0.909 vs 0.871, 0.913 vs 0.859; NRI, 0.113, 0.076, 0.108; respectively). The validation cohort confirmed a similar pattern.Conclusions: Updating cut-off values of severity scoring systems for CAP orchestrate improvement in predictive accuracy, suggesting that it may facilitate the rationalization of clinical triage decision-making and further reduce mortality. The current studies provide the first known prospective evidence of potential benefit of the updating cut-off values of severity scoring systems for CAP in predictive accuracy.Key messagesUpdating cut-off values were performed better for predicting mortality.Bettered scoring systems orchestrated higher convergences.Bettered scoring systems demonstrated greater predictive accuracies for mortality.

qSOFA predicted pneumonia mortality better than minor criteria and worse than CURB-65 with robust elements and higher convergence.

BACKGROUND: Limited data are available on the discriminatory capacity of quick sequential [sepsis-related] organ failure assessment (qSOFA) versus IDSA/ATS minor criteria for predicting mortality in patients with community-acquired pneumonia (CAP). METHODS: An observational prospective cohort study of 2116 patients with CAP was performed. Construct validity was determined using Cronbach α. Discrimination was assessed using the area under the receiver operating characteristic curve (AUROC) and net reclassification improvement (NRI). RESULTS: Overall in-hospital mortality was 6.43%. Mortality was 25.96% for patients with a qSOFA score of 2 or higher versus 3.05% for those with a qSOFA score less than 2 (odds ratio for mortality 6.57, P < 0.0001), and 13.85% for patients with at least 3 minor criteria versus 2.03% for those with 2 or fewer minor criteria (odds ratio for mortality 2.27, P < 0.0001). qSOFA had a higher correlation with mortality than minor criteria, as well as higher internal consistency (Cronbach alpha 0.43 versus 0.14) and diagnostic values of individual elements (larger AUROCs and higher Youden's indices). qSOFA ≥2 was less sensitive but more specific for predicting mortality than ≥3 minor criteria (qSOFA sensitivity 59.6%, specificity 88.3% and positive likelihood ratio 5.11 versus ≥3 minor criteria sensitivity 80.1%, specificity 65.8% and positive likelihood ratio 2.34). The predictive validity of qSOFA was good for mortality (AUROC = 0.868), was statistically greater than minor criteria, was equal to pneumonia severity index, and was inferior compared with CURB-65 (AUROC, 0.824, 0.902, 0.919; NRI, 0.088, -0.068, -0.103; respectively). CONCLUSIONS: The qSOFA predicted mortality in CAP better than IDSA/ATS minor criteria and worse than CURB-65 with robust elements and higher convergence. qSOFA as a bedside prompt might be positioned as a proxy for minor criteria and increase the recognition and thus merit more appropriate management of CAP patients likely to fare poorly, which might have implications for more accurate clinical triage decisions.

The potential use of straw-derived biochar as the adsorbent for La(III) and Nd(III) removal in aqueous solutions.

Recent attention on the lanthanides (Ln) contaminant such as lanthanum (La) and neodymium (Nd) extensively used in industry has aroused the great desire for the effective adsorbent. Biochar, relying on its high selectivity and optional ease, is regarded as a promising adsorbent for lanthanides removal although the evaluation of the efficiency and mechanism of La(III) and Nd(III) adsorption on biochar still lags. Here, we investigated the aqueous adsorption processes through SEM, TEM, EDS, FTIR and Raman spectra, XPS, and batch experiments. The porous structure of biochar and the complex functional groups on its surface contributed to the La(III) and Nd(III) removal processes. The kinetic of La(III) and Nd(III) adsorption agreed well with the pseudo-second-order kinetic model. The adsorption capacity showed a strong positive correlation with pH value. However, it was only slightly altered and robust in La(III) and Nd(III) adsorption respectively. The isotherm results reflected significant fitting to the Sips model as well as Langmuir and Freundlich model. Thermodynamic demonstrated the spontaneity, endothermic nature, and temperature favor of the adsorptions on biochar surface (La: ΔH0=35.39 (kJ/Mol), ΔS0=104.71(J*Mol-1*K-1) and ΔG0<0; Nd: ΔH0=16.71(KJ/mol), ΔS0=119.41(J*Mol-1*K-1) and ΔG0<0). Both the La(III) and Nd(III) removal processes combined physical and chemical adsorptions. Therefore, biochar could be a potential green material for the lanthanum and neodymium adsorption with high efficiency.

Cold-inducible RNA-binding protein might determine the severity and the presences of major/minor criteria for severe community-acquired pneumonia and best predicted mortality.

BACKGROUND: Severity of community-acquired pneumonia (CAP) depends on microbial pathogenicity, load and virulence, and immune responses. The Infectious Disease Society of America and the American Thoracic Society (IDSA/ATS) minor criteria responsible for clinical triage of patients with CAP are of unequal weight in predicting mortality. It is unclear whether the IDSA/ATS major/minor criteria might be strongly and positively associated with the immune responses. It is warranted to explore this intriguing hypothesis. METHODS: A prospective cohort study of 404 CAP patients was performed. Cold-inducible RNA-binding protein (CIRP) levels were measured using a sandwich-based enzyme-linked immunosorbent assay. The receiver operating characteristic curves were created and the areas under the curves were calculated to illustrate and compare the accuracy of the indices. RESULTS: Severe CAP patients meeting the major criteria had the highest plasma concentrations of CIRP. The more the number of most predictive minor criteria strongly associated to mortality, i.e. arterial oxygen pressure/fraction inspired oxygen ≤ 250 mmHg, confusion, and uremia, present, the higher the CIRP level. Interestingly, the patients with non-severe CAP meeting the most predictive minor criteria demonstrated unexpectedly higher CIRP level compared with the patients with severe CAP not fulfilling the criteria. Procalcitonin (PCT), interleukin-6 (IL-6), C-reactive protein (CRP), sequential organ failure assessment (SOFA) and pneumonia severity index (PSI) scores, and mortality confirmed similar intriguing patterns. CIRP was strongly linked to PCT, IL-6, CRP, minor criteria, SOFA and PSI scores, and mortality (increased odds ratio 3.433). The pattern of sensitivity, specificity, positive predictive value, and Youden's index of CIRP ≥ 3.50 ng/mL for predicting mortality was the optimal. The area under the receiver operating characteristic curve of CIRP was the highest among the indices. CONCLUSIONS: CIRP levels were strongly correlated with the IDSA/ATS major/minor criteria. CIRP might determine the severity and the presences of major/minor criteria and best predicted mortality, and a CIRP of ≥ 3.50 ng/mL might be more valuable cut-off value for severe CAP, suggesting that CIRP might be a novel and intriguing biomarker for pneumonia to monitor host response and predict mortality, which might have implications for more accurate clinical triage decisions.

Soil acidification alters root morphology, increases root biomass but reduces root decomposition in an alpine grassland.

Soil acidification has been expanding in many areas of Asia due to increasing reactive nitrogen (N) inputs and industrial activities. While the detrimental effects of acidification on forests have been extensively studied, less attention has been paid to grasslands, particularly alpine grasslands. In a soil pH manipulation experiment in the Qinghai-Tibet Plateau, we examined the effects of soil acidification on plant roots, which account for the major part of alpine plants. After three years of manipulation, soil pH decreased from 6.0 to 4.7 with the acid-addition gradient, accompanied by significant changes in the availability of soil nitrogen, phosphorus and cations. Plant composition shifted with the soil acidity, with graminoids replacing forbs. Differing from findings in forests, soil acidification in the alpine grassland increased root biomass by increasing the fraction of coarse roots and the production of fine roots, corresponding to enhanced sedge and grass biomass, respectively. In addition, litter decomposability decreased with altered root morphological and chemical traits, and soil acidification slowed root decomposition by reducing soil microbial activity and litter quality. Our results showed that acidification effect on root dynamics in our alpine grassland was significantly different from that in forests, and supported similar results obtained in limited studies in other grassland ecosystems. These results suggest an important role of root morphology in mediating root dynamics, and imply that soil acidification may lead to transient increase in soil carbon stock as root standing biomass and undecomposed root litter. These changes may reduce nutrient cycling and further constrain ecosystem productivity in nutrient-limiting alpine systems.

Impacts of drought and nitrogen enrichment on leaf nutrient resorption and root nutrient allocation in four Tibetan plant species.

Plant nutrient resorption, a process by which plant withdraws nutrients from senescing structures to developing tissues, can significantly affect plant growth, litter decomposition and nutrient cycling. Global change factors, such as nitrogen (N) deposition and altered precipitation, may mediate plant nutrient resorption and allocation. The ongoing global change is accompanied with increased N inputs and drought frequency in many regions. However, the interactive effects of increased N availability and drought on plant nutrient-responses remain largely unclear. In a pot experiment, we examined the impacts of N enrichment and drought on leaf N and phosphorous (P) resorption and root nutrient allocation in four species from the Qinghai-Tibet Plateau, including two graminoid species (Kobresia capillifolia and Elymus nutans) and two forb species (Delphinium kamaonense and Aster diplostephioides). Our results showed divergent resorption patterns within the two functional groups. E. nutans and D. kamaonense showed stronger N resorption than K. capillifolia and A. diplostephioides. N addition did not alter their N resorption efficiencies, but decreased the N resorption proficiencies of the former two species. In contrast, drought did not affect N or P resorption proficiencies, but decreased N resorption efficiency of K. capillifolia. Besides, N addition facilitated P resorption in K. capillifolia and D. kamaonense, and drought did the same in A. diplostephioides, suggesting that P resorption plays an important role in nutrient conservation in these species. Moreover, species with stronger N resorption allocated more biomass C or N to aboveground and enhanced their litter quality under N enrichment, while species with weaker resorption allocated more biomass C and/or N to belowground part under drought. Together, these results show that the responses of nutrient resorption and allocation to N enrichment and drought are highly species-specific. Future studies should take these differential responses into consideration to better predict litter decomposition and ecosystem nutrient cycling.

Effects of global change factors and living roots on root litter decomposition in a Qinghai-Tibet alpine meadow.

Roots account for a major part of plant biomass in Tibetan alpine meadows. Understanding root decomposition with global change is key to predict carbon (C) and nutrient dynamics on the Qinghai-Tibet Plateau. Yet, few experiments have carefully examined root decomposition as influenced by global change. We conducted a field study to investigate the effects of nitrogen (N) addition, air warming, precipitation change, and the presence/absence of living roots on root decomposition in a Tibetan alpine meadow. Our results showed that N addition increased the mass and C remaining, and induced N accumulation in the litter. Increased precipitation significantly amplified the positive effect of N addition on litter mass remaining. The presence of alive roots in the litterbags decreased root litter C remaining but significantly increased N and phosphorus remaining of the litter. However, we did not find any significant effects of air warming on the litter decomposition. In the Qinghai-Tibet Plateau, N deposition is predicted to increase and precipitation regime is predicted to change. Our results suggest that the interaction between increased N and precipitation may reduce root decomposition in the Qinghai-Tibet Plateau in the future, and that the large stock of living roots exert a dominant impact on nutrient dynamics of root decomposition in the Tibetan alpine systems.

Correction to: Scored minor criteria for severe community-acquired pneumonia predicted better.

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Scored minor criteria for severe community-acquired pneumonia predicted better.

BACKGROUND: Infectious Disease Society of America/American Thoracic Society (IDSA/ATS) minor criteria for severe community-acquired pneumonia (CAP) are of unequal weight in predicting mortality, but the major problem associated with IDSA/ATS minor criteria might be a lack of consideration of weight in prediction in clinical practice. Would awarding different points to the presences of the minor criteria improve the accuracy of the scoring system? It is warranted to explore this intriguing hypothesis. METHODS: A total of 1230 CAP patients were recruited to a retrospective cohort study. This was tested against a prospective two-center cohort of 1749 adults with CAP. 2 points were assigned for the presence of PaO2/FiO2 ≤ 250 mmHg, confusion, or uremia on admission and 1 point for each of the others. RESULTS: The mortality rates, and sequential organ failure assessment (SOFA) and pneumonia severity index (PSI) scores increased significantly with the numbers of IDSA/ATS minor criteria present and minor criteria scores. The correlations of the minor criteria scores with the mortality rates were higher than those of the numbers of IDSA/ATS minor criteria present. As were the correlations of the minor criteria scores with SOFA and PSI scores, compared with the numbers of IDSA/ATS minor criteria present. The pattern of sensitivity, specificity, positive predictive value, and Youden's index of scored minor criteria of ≥2 scores or the presence of 2 or more IDSA/ATS minor criteria for prediction of mortality was the best in the retrospective cohort, and the former was better than the latter. The validation cohort confirmed a similar pattern. The area under the receiver operating characteristic curve of scored minor criteria was higher than that of IDSA/ATS minor criteria in the retrospective cohort, implying higher accuracy of scored version for predicting mortality. The validation cohort confirmed a similar paradigm. CONCLUSIONS: Scored minor criteria orchestrated improvements in predicting mortality and severity in patients with CAP, and scored minor criteria of ≥2 scores or the presence of 2 or more IDSA/ATS minor criteria might be more valuable cut-off value for severe CAP, which might have implications for more accurate clinical triage decisions.

Priority for Treatment and Intensive Care of Patients With Non-Severe Community-Acquired Pneumonia.

BACKGROUND: The Infectious Disease Society of America/the American Thoracic Society (IDSA/ATS) minor criteria for severe community-acquired pneumonia (CAP) are of unequal weight in predicting mortality. It is unclear whether the patients with non-severe CAP meeting the minor criteria most strongly associated to mortality should have the priority for treatment and intensive care. It is warranted to explore this intriguing hypothesis. METHODS: A retrospective cohort study of 1230 patients with CAP was performed. This was tested against a prospective 2-center cohort of 1749 adults with CAP. RESULTS: The patients with CAP fulfilling the predictive findings most strongly associated to mortality, i.e. PaO2/FiO2 ≤ 250 mm Hg, confusion, and uremia, showed higher mortality rates than those not fulfilling the predictive findings in subgroup analyses of the retrospective cohort. The more the number of predictive findings present, the higher the mortality rates. The prospective cohort confirmed a similar pattern. Interestingly, the patients with non-severe CAP meeting the predictive findings demonstrated unexpectedly higher mortality rates compared with the patients with severe CAP not meeting the predictive findings in the prospective cohort (P = 0.003), although there only existed death of an uptrend in the retrospective cohort. Two similar and intriguing paradigms about sequential organ failure assessment (SOFA) scores and pneumonia severity index (PSI) scores were confirmed in the 2 cohorts. CONCLUSIONS: The patients with non-severe CAP fulfilling the predictive findings most strongly associated to mortality demonstrated higher SOFA and PSI scores and mortality rates, and might have the priority for treatment and intensive care.

Local root growth and death are mediated by contrasts in nutrient availability and root quantity between soil patches.

Plants are thought to be able to regulate local root growth according to its overall nutrient status as well as nutrient contents in a local substrate patch. Therefore, root plastic responses to environmental changes are probably co-determined by local responses of root modules and systematic control of the whole plant. Recent studies showed that the contrast in nutrient availability between different patches could significantly influence the growth and death of local roots. In this study, we further explored, beside nutrient contrast, whether root growth and death in a local patch are also affected by relative root quantity in the patch. We conducted a split-root experiment with different splitting ratios of roots of Canada goldenrod (Solidago canadensis) individuals, as well as high- (5× Hoagland solution versus water) or low- (1× Hoagland solution versus water) contrast nutrient conditions for the split roots. The results showed that root growth decreased in nutrient-rich patches but increased in nutrient-poor patches when more roots co-occurred in the same patches, irrespective of nutrient contrast condition. Root mortality depended on contrasts in both root quantity and nutrients: in the high-nutrient-contrast condition, it increased in nutrient-rich patches but decreased in nutrient-poor patches with increasing root proportion; while in the low-nutrient-contrast condition, it showed the opposite trend. These results demonstrated that root growth and death dynamics were affected by the contrast in both nutrient availability and root quantity between patches. Our study provided ecological evidence that local root growth and death are mediated by both the responses of root modules to a nutrient patch and the whole-plant nutrient status, suggesting that future work investigating root production and turnover should take into account the degree of heterogeneity in nutrient and root distribution.

XANES and EXAFS investigation of uranium incorporation on nZVI in the presence of phosphate.

Effect of phosphate on the reduction of U(VI) on nZVI was determined by batch, XPS, XANES and EXAFS techniques. The batch experiments showed that nZVI was quite effective for the removal of uranium under the anaerobic conditions, whereas the addition of phosphate enhanced uranium removal over wide pH range. At low pH, the reduction of U(VI) to U(IV) significantly decreased with increasing phosphate concentration by XPS and XANES analysis. According to EXAFS analysis, the occurrence of UU shell at 10 mg/L phosphate and pH 4.0 was similar to that of U(IV)O2(s), whereas the UP and UFe shells were observed at 50 mg/L phosphate, revealing that reductive co-precipitate (U(IV)O2(s)) and precipitation of uranyl-phosphate were observed at low and high phosphate, respectively. The findings are crucial for the prediction of the effect of phosphate on the speciation and binding of uranium by nZVI at low pH, which is significant in controlling the mobility of U(VI) in contaminated environments.

Protective effect of Yiguanjian decoction against DNA damage on concanavalin A-induced liver injury mice model.

OBJECTIVE: To investigate the inhibitory effect of Yiguanjian decoction (YD) on DNA damage in Concanavalin A (Con A)-induced liver injury mice model and to explain the possible mechanism. METHODS: METHODS: Totally 120 male BALB/c mice were randomly divided into 6 groups, 20 mice each: normal group, model group, Bifendate group, YD low dose group, YD middle dose group and YD high dose group. Except normal group, liver injury model induced by Con A was established. While modeling, each mouse in YD group was given YD (0.4 mL/20 g per day) by intragastric administration (0.13 g YD for YD low dose group; 0.26 g for YD middle dose group; 0.52 g for YD high dose group). Bifendate group was given Bifendate (0.2 g·kg-1·d-1) by gavage. Normal group and model group were fed with same volume of physiological saline daily. After 8 weeks, the serum alanine transaminase (ALT) and aspartate transaminase (AST) were tested. The hematoxylin-eosin staining was used to evaluate the grade of liver inflammation and liver fibrosis stage. Hepatocellular DNA damage was detected by single cell gel electrophoresis technology. The protein expression of tumor necrosis factor-α (TNF-α), Bax and MutT Homolog 1 (MTH1) was detected by western blotting and enzyme linked immunosorbent assay. Bax mRNA and MTH1 mRNA were detected by Real-time Polymerase Chain Reaction (PCR). RESULTS: YD can improve the degree of liver inflammation and fibrosis in the liver of chronic hepatitis mice, the dose effect relationship is remarkable (P < 0.05). YD can reduce liver cell DNA damage. The difference between YD middle dose group and model group was statistically significant (P < 0.05). YD middle dose group had decreased the protein expression of TNF-α in the mice liver of immunological liver injury (P < 0.05). YD can increase the protein expression of Bax (P < 0.05). Compared with normal group, the protein expression of MTH1 was decreased (P < 0.05), but there was no statistical significance between YD group and model group (P > 0.05). YD can increase the mRNA expression of Bax and MTH1 (both P < 0.05). CONCLUSION: YD can effectively inhibit the DNA damage in immunological liver injury mice, the mechanism may be that it can decrease the TNF-α and increase the Bax and MTH1 expression.

Modified IDSA/ATS Minor Criteria for Severe Community-Acquired Pneumonia Best Predicted Mortality.

It is not clear whether the IDSA/ATS minor criteria for severe community-acquired pneumonia (CAP) could be simplified or even be modified to orchestrate improvements in predicting mortality.A retrospective cohort study of 1230 CAP patients was performed to simplify and to modify the scoring system by excluding 4 noncontributory or infrequent variables (leukopenia, hypothermia, hypotension, and thrombocytopenia) and by excluding these variables and then adding age ≥65 years, respectively. The simplification and modification were tested against a prospective 2-center validation cohort of 1409 adults with CAP.The increasing numbers of IDSA/ATS, simplified, and modified minor criteria present in the retrospective cohort were positively associated with the mortality, showing significant increased odds ratios for mortality of 2.711, 4.095, and 3.755, respectively. The validation cohort confirmed a similar pattern. The sensitivity, specificity, positive predictive value, and Youden index of modified minor criteria for mortality prediction were the best pattern in the retrospective cohort. High values of corresponding indices were confirmed in the validation cohort. The highest accuracy of the modified version for predicting mortality in the retrospective cohort was illustrated by the highest area under the receiver operating characteristic curve of 0.925 (descending order: modified, simplified, and IDSA/ATS minor criteria). The validation cohort confirmed a similar paradigm.The IDSA/ATS minor criteria could be simplified to 5 variables and then be modified to orchestrate improvements in predicting mortality in CAP patients. The modified version best predicted mortality. These were more suitable for clinic and emergency department.

CUR-65 Score for Community-Acquired Pneumonia Predicted Mortality Better Than CURB-65 Score in Low-Mortality Rate Settings.

BACKGROUND: It is not clear whether low-blood pressure criterion could be removed from CURB-65 (confusion, urea >7 mmol/L, respiratory rate ≥30/min, low blood pressure and age ≥65 years) score to orchestrate an improvement in identifying patients with community-acquired pneumonia (CAP) in low-mortality rate settings. METHODS: A retrospective cohort study of 1,230 CAP patients was performed to simplify the CURB-65 scoring system by excluding low-blood pressure variable. The simplification was validated in a prospective 2-center cohort of 1,409 adults with CAP. RESULTS: The hospital mortalities were 1.3% and 3.8% in the retrospective and prospective cohorts, respectively. The mortality rates in the 2 cohorts increased directly with the increasing scores, showing significant increased odds ratios for mortality. The pattern of sensitivity, specificity, positive predictive value and Youden's index of a CUR-65 (Confusion, Urea >7 mmol/L, Respiratory rate ≥30/min and age ≥65 years) score of ≥2 for prediction of mortality was better than that of a CURB-65 score of ≥3 in the retrospective cohort. Higher values of corresponding indices were confirmed in the validation cohort. The higher accuracy of CUR-65 score for predicting mortality was illustrated by the area under the receiver operating characteristic curve of 0.937, compared with 0.915 for CURB-65 score in the retrospective cohort (P = 0.0073). The validation cohort confirmed a similar paradigm (0.953 versus 0.907, P = 0.0002). CONCLUSIONS: CURB-65 score could be simplified by removing low blood pressure to orchestrate an improvement in predicting mortality in CAP patients who have a low risk of death. A CUR-65 score of ≥2 might be a more valuable cutoff value for severe CAP.

Mortality among severe community-acquired pneumonia patients depends on combinations of 2007 IDSA/ATS minor criteria.

OBJECTIVES: The individual 2007 Infectious Disease Society of America (IDSA)/American Thoracic Society (ATS) minor criteria for severe community-acquired pneumonia (CAP) are of unequal weight in predicting mortality. It is not clear whether the combinations of predictive findings might imply diverse severities or different mortalities. METHODS: A prospective two centre cohort study was performed of 385 severe CAP patients fulfilling three or more IDSA/ATS minor criteria amongst 1430 patients. RESULTS: Hospital mortality rose sharply from 5.7%, 9.9%, and 16.5%, respectively, for patients with none of three predictive findings most strongly associated to mortality (PaO2/FiO2 ≤ 250mm Hg, confusion and uraemia), one of those, and two of those to 38.6% for patients with all those (p<0.001). The number of three predictive findings present had a significantly increased odds ratio for mortality of 2.796 (p<0.001), and had the degree of positive association with sequential organ failure assessment scores at 72hours, incurring significantly longer hospital stay and higher costs. CONCLUSIONS: Different combinations of 2007 IDSA/ATS minor criteria for severe CAP were associated to diverse severities and different mortalities. The combination of PaO2/FiO2 ≤ 250mm Hg, confusion and uraemia predicted more severity and higher mortality compared with others.

Associations of radiological features in Mycoplasma pneumoniae pneumonia.

INTRODUCTION: The associations of radiological features with clinical and laboratory findings in Mycoplasma pneumoniae infection are poorly understood. The purpose of this study was to assess the associations. MATERIAL AND METHODS: A retrospective cohort study of 1230 patients with community-acquired pneumonia was carried out between January 2005 and December 2009. The diagnosis of M. pneumoniae infection was made using the indirect microparticle agglutinin assay and enzyme-linked immunosorbent assay. RESULTS: Females were more susceptible to M. pneumoniae infection. Ground-glass opacification on radiographs was positively associated with M. pneumoniae-IgM titres (rank correlation coefficient (r s) = 0.141, p = 0.006). The left upper lobe was more susceptible to infection with M. pneumoniae compared with other pathogens. More increases in the risk of multilobar opacities were found among older or male patients with M. pneumoniae pneumonia (odds ratio, 1.065, 3.279; 95% confidence interval, 1.041-1.089, 1.812-5.934; p < 0.001, p < 0.001; respectively). Patients with M. pneumoniae pneumonia showing multilobar opacities or consolidation had a significantly longer hospital length of stay (r s = 0.111, r s = 0.275; p = 0.033, p < 0.001; respectively), incurring significantly higher costs (r s = 0.119, r s = 0.200; p = 0.022, p < 0.001; respectively). CONCLUSIONS: Our study highlighted female susceptibility to M. pneumoniae pneumonia and the association of ground-glass opacification with higher M. pneumoniae-IgM titres. The left upper lobe might be more susceptible to M. pneumoniae infection. Older or male patients with M. pneumoniae pneumonia were more likely to show multilobar opacities. Multilobar opacities and consolidation were positively associated with hospital length of stay and costs.