Effects of age, comorbidity and adherence to current antimicrobial guidelines on mortality in hospitalized elderly patients with community-acquired pneumonia.

BACKGROUND: Limited information exists on the clinical characteristics predictive of mortality in patients aged ≥65 years in many countries. The impact of adherence to current antimicrobial guidelines on the mortality of hospitalized elderly patients with community-acquired pneumonia (CAP) has never been assessed. METHODS: A total of 3131 patients aged ≥65 years were enrolled from a multi-center, retrospective, observational study initiated by the CAP-China network. Risk factors for death were screened with multivariable logistic regression analysis, with emphasis on the evaluation of age, comorbidities and antimicrobial treatment regimen with regard to the current Chinese CAP guidelines. RESULTS: The mean age of the study population was 77.4 ± 7.4 years. Overall in-hospital and 60-day mortality were 5.7% and 7.6%, respectively; these rates were three-fold higher in those aged ≥85 years than in the 65-74 group (11.9% versus 3.2% for in-hospital mortality and 14.1% versus 4.7% for 60-day mortality, respectively). The mortality was significantly higher among patients with comorbidities compared with those who were otherwise healthy. According to the 2016 Chinese CAP guidelines, 62.1% of patients (1907/3073) received non-adherent treatment. For general-ward patients without risk factors for Pseudomonas aeruginosa (PA) infection (n = 2258), 52.3% (1094/2090) were over-treated, characterized by monotherapy with an anti-pseudomonal ß-lactam or combination with fluoroquinolone + ß-lactam; while 71.4% of intensive care unit (ICU) patients (120/168) were undertreated, without coverage of atypical bacteria. Among patients with risk factors for PA infection (n = 815), 22.9% (165/722) of those in the general ward and 74.2% of those in the ICU (69/93) were undertreated, using regimens without anti-pseudomonal activity. The independent predictors of 60-day mortality were age, long-term bedridden status, congestive heart failure, CURB-65, glucose, heart rate, arterial oxygen saturation (SaO2) and albumin levels. CONCLUSIONS: Overtreatment in general-ward patients and undertreatment in ICU patients were critical problems. Compliance with Chinese guidelines will require fundamental changes in standard-of-care treatment patterns. The data included herein may facilitate early identification of patients at increased risk of mortality. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov ( NCT02489578 ).

Regulation of genes encoding the major surface protease of Leishmania chagasi via mRNA stability.

The intercoding regions between many Leishmania sp. genes regulate their mRNA expression. The MSPL mRNA, encoding a subclass of the major surface protease (MSP) of Leishmania chagasi, increases in abundance, when protein synthesis is arrested, while alpha-tubulin (alpha-TUB) mRNA and most other mRNAs do not. We found that the intercoding region between MSPL-coding regions, when cloned downstream of the beta-galactosidase reporter gene (beta-GAL), caused beta-GAL mRNA to increase 8- to 10-fold after inhibiting protein synthesis with cycloheximide. Stable L. chagasi transfectants containing hybrid MSPL/alpha-TUB intercoding regions cloned downstream of beta-GAL were made. The alpha-TUB intercoding region induced high-level baseline beta-GAL mRNA that increased only 1.3-fold after incubation with cycloheximide. In contrast, the MSPL intercoding region, as well as constructs containing nucleotides 303-505 from the MSPL 3'UTR, caused steady-state beta-GAL mRNA levels in the absence of cycloheximide that were approximately 10% of alpha-TUB constructs. These levels increased between 4.4- and 13.2-fold after cycloheximide was added. Constructs containing half of this region (303-394 or 395-505) produced intermediate levels of beta-GAL mRNA and intermediate levels of cycloheximide induction. The kinetics of cycloheximide induction of beta-GAL mRNA was similar with region 303-505 constructs as with constructs bearing the entire endogenous MSPL intercoding region. Furthermore, region 303-505 increased reporter mRNA abundance after cycloheximide by increasing mRNA half-life. Hence, we have identified a 202-nucleotide region within the MSPL 3'UTR that is in part responsible for cycloheximide induction. We hypothesize that this region may interact with labile regulatory protein factor(s).

Leishmania chagasi: the alpha-tubulin intercoding region results in constant levels of mRNA abundance despite protein synthesis inhibition and growth state.

The intercoding regions of many Leishmania sp. genes have been implicated in the regulation of mRNA processing, stability, and translation. Herein we show that the intercoding region of the Leishmania chagasi alpha-tubulin gene (alpha-TUB) confers stable beta-galactosidase (beta-GAL) reporter mRNA levels during promastigote growth and development in vitro and during protein synthesis inhibition. The abundance of both endogenous alpha-TUB mRNA and beta-GAL mRNA from a beta-GAL coding region situated upstream of the alpha-TUB intercoding region did not change significantly as promastigotes grew from logarithmic to stationary phase in vitro and the half-life of the beta-GAL mRNA remained constant. The abundance of both the endogenous alpha-TUB and the beta-GAL mRNA increased by less than 2-fold after protein synthesis inhibition corresponding to a moderate increase in mRNA half-life. These data suggest that the alpha-TUB intercoding region is an excellent control for the study of the regulation of other differentially expressed genes.