Prevalence of the virulence genes and their correlation with carbapenem resistance amongst the Pseudomonas aeruginosa strains isolated from a tertiary hospital in China.

Pseudomonas aeruginosa is one of the top-listed pathogens in nosocomial infection. It is notorious for its complicated virulence system and rapid adaptability to drugs or antimicrobials. In this study, we aimed to evaluate the prevalence of sixteen virulence genes in four groups including type III secretion system, biofilm formation, extracellular toxin biosynthesis and enzymes amongst 209 clinical Pseudomonas aeruginosa strains. We investigated the different distribution patterns of virulence genotypes based on carbapenem-resistant phenotype or the carriage of carbapenemase genes. The detection rate of each virulence gene varied greatly. phzM and plcN were detected in all collected strains, while pilB and exoU were only carried by a small portion of isolates (6.7% and 16.3%). Additionally, the number of genotypes observed in each group of examined virulence genes ranged from 4 to 8. Only the distribution of genotypes of type III secretion system showed statistical difference between carbapenem-mediated or carbapenem-resistant and carbapenem-sensitive strains. The virulence genotype of Pseudomonas aeruginosa was possibly interrelated to its resistance mechanism. Further research suggested that one particular TTSS genotype exhibited higher ratio in carbapenemase-producing strains and exoS was less frequently detected in CRPA strains carrying carbapenemase gene. Generally, the significant genetic diversity of virulence genes amongst Pseudomonas aeruginosa strains was highlighted in this study. Specific TTSS genotypes were associated with carbapenem-resistance. In particular, certain incompatibility might exist between exoS and carbapenemase genes, which provided valuable information for further understanding the relationship between carbapenem resistance and virulence.

Trial of Galcanezumab in Prevention of Episodic Cluster Headache.

BACKGROUND: Episodic cluster headache is a disabling neurologic disorder that is characterized by daily headache attacks that occur over periods of weeks or months. Galcanezumab, a humanized monoclonal antibody to calcitonin gene-related peptide, may be a preventive treatment for cluster headache. METHODS: We enrolled patients who had at least one attack every other day, at least four total attacks, and no more than eight attacks per day during a baseline assessment, as well as a history of cluster headache periods lasting at least 6 weeks, and randomly assigned them to receive galcanezumab (at a dose of 300 mg) or placebo, administered subcutaneously at baseline and at 1 month. The primary end point was the mean change from baseline in the weekly frequency of cluster headache attacks across weeks 1 through 3 after receipt of the first dose. The key secondary end point was the percentage of patients who had a reduction from baseline of at least 50% in the weekly frequency of cluster headache attacks at week 3. Safety was also assessed. RESULTS: Recruitment was halted before the trial reached the planned sample size of 162 because too few volunteers met the eligibility criteria. Of 106 enrolled patients, 49 were randomly assigned to receive galcanezumab and 57 to receive placebo. The mean (±SD) number of cluster headache attacks per week in the baseline period was 17.8±10.1 in the galcanezumab group and 17.3±10.1 in the placebo group. The mean reduction in the weekly frequency of cluster headache attacks across weeks 1 through 3 was 8.7 attacks in the galcanezumab group, as compared with 5.2 in the placebo group (difference, 3.5 attacks per week; 95% confidence interval, 0.2 to 6.7; P = 0.04). The percentage of patients who had a reduction of at least 50% in headache frequency at week 3 was 71% in the galcanezumab group and 53% in the placebo group. There were no substantial between-group differences in the incidence of adverse events, except that 8% of the patients in the galcanezumab group had injection-site pain. CONCLUSIONS: Galcanezumab administered subcutaneously at a dose of 300 mg once monthly reduced the weekly frequency of attacks of episodic cluster headache across weeks 1 through 3 after the initial injection, as compared with placebo. (Funded by Eli Lilly; ClinicalTrials.gov number, NCT02397473.).

Evaluation of the EUCAST Rapid Antimicrobial Susceptibility Test for Enterobacterales-Containing Blood Cultures in China.

Bloodstream infection (BSI) is defined by the presence of microbes in the bloodstream and has high mortality. Early antimicrobial therapy is key to treating BSI patients. Because of potential antimicrobial resistance, rapid evaluation for the most suitable antimicrobial therapy is important for appropriate treatment. In China, the current workflow of microbiological diagnosis in BSI involves blood culture, species identification, and antimicrobial susceptibility testing, which takes around 3 days. However, this delay could lead to worse symptoms. To rapidly and accurately assess antimicrobial susceptibility, in this study, we applied EUCAST rapid antimicrobial susceptibility testing (RAST) to determine the antimicrobial susceptibilities of the most frequently detected Enterobacterales sampled in China, including Escherichia coli and Klebsiella pneumoniae. Based on EUCAST guidelines, we evaluated its efficiencies with six commercially available antimicrobials, including imipenem (10 µg), meropenem (10 µg), ciprofloxacin (5 µg), levofloxacin (5 µg), amikacin (30 µg), and trimethoprim-sulfamethoxazole (1.25/23.75 µg), with bacterium-spiked blood cultures. In addition, we developed potential breakpoints for a recently introduced antimicrobial, 30/20 µg ceftazidime-avibactam, which has high potential for treating multidrug-resistant Enterobacterales. Our results showed that EUCAST RAST is a reliable method for rapidly determining the antimicrobial susceptibilities of BSI-causing bacteria in China, with an overall categorical agreement rate at 8 h of ≥90%. The breakpoints developed in this study can categorize the isolates sampled in this study with an accuracy of 93%. Results from our experiments can be applied to clinically determine the microbial susceptibility of BSI-causing bacteria within 8 h and benefit clinical diagnostics for BSI patients.

Evaluation of respiratory samples in etiology diagnosis and microbiome characterization by metagenomic sequencing.

BACKGROUND: The application of clinical mNGS for diagnosing respiratory infections improves etiology diagnosis, however at the same time, it brings new challenges as an unbiased sequencing method informing all identified microbiomes in the specimen. METHODS: Strategy evaluation and metagenomic analysis were performed for the mNGS data generated between March 2017 and October 2019. Diagnostic strengths of four specimen types were assessed to pinpoint the more appropriate type for mNGS diagnosis of respiratory infections. Microbiome complexity was revealed between patient cohorts and infection types. A bioinformatic pipeline resembling diagnosis results was built based upon multiple bioinformatic parameters. RESULTS: The positive predictive values (PPVs) for mNGS diagnosing of non-mycobacterium, Nontuberculous Mycobacteria (NTM), and Aspergillus were obviously higher in bronchoalveolar lavage fluid (BALF) demonstrating the potency of BALF in mNGS diagnosis. Lung tissues and sputum were acceptable for diagnosis of the Mycobacterium tuberculosis (MTB) infections. Interestingly, significant taxonomy differences were identified in sufficient BALF specimens, and unique bacteriome and virome compositions were found in the BALF specimens of tumor patients. Our pipeline showed comparative diagnostic strength with the clinical microbiological diagnosis. CONCLUSIONS: To achieve reliable mNGS diagnosis result, BALF specimens for suspicious common infections, and lung tissues and sputum for doubtful MTB infections are recommended to avoid the false results given by the complexed respiratory microbiomes. Our developed bioinformatic pipeline successful helps mNGS data interpretation and reduces manual corrections for etiology diagnosis.

Recent progress in heterogeneous metal and metal oxide catalysts for direct dehydrogenation of ethane and propane.

Catalytic non-oxidative direct dehydrogenation of light alkanes serves as an effective reinforcement to selectively produce the corresponding olefins, and the heterogeneous metals and metal oxides, not limited to the commercially used Pt- and Cr-based catalysts, are widely investigated to enhance the efficiency. In this review, we outline the progress of these dehydrogenation catalysts that have been mainly developed in the past five years. For different classes of the most-promising catalysts in the selective dehydrogenation of ethane-to-ethylene and propane-to-propylene, their syntheses, structural information, catalytic properties and mechanisms are comparatively summarized.

Phase 3 randomized, placebo-controlled study of galcanezumab in patients with chronic cluster headache: Results from 3-month double-blind treatment.

OBJECTIVE: To report efficacy and safety of galcanezumab in adults with chronic cluster headache. BACKGROUND: Galcanezumab is a humanized monoclonal antibody that binds to calcitonin gene-related peptide and inhibits its biological activity. METHODS: This study comprised a prospective baseline period, a 12-week double-blind, placebo-controlled treatment period, and a 52-week open-label period. Up to six protocol-specified concomitant preventive medications were allowed if patients were on a stable dose for 2 months prior to the prospective baseline period. Patients were randomized 1:1 to monthly subcutaneous galcanezumab (300 mg) or placebo. The primary endpoint was overall mean change from baseline in weekly attack frequency with galcanezumab compared to placebo. Key secondary endpoints were ≥50% response rate and percentage of patients meeting sustained response. Results from the double-blind treatment period are reported. RESULTS: A total of 237 patients were randomized and treated (120 placebo; 117 galcanezumab). At baseline, the mean age was 45 years and 63% were using ≥1 preventive drug. The primary endpoint was not met; mean change in weekly attack frequency was -4.6 placebo versus -5.4 galcanezumab (p = 0.334). Key secondary endpoints also were not met. Injection site-related treatment-emergent adverse events were more common in the galcanezumab than the placebo group, with significantly more injection site erythema. CONCLUSION: Treatment with galcanezumab 300 mg did not achieve its primary and key secondary endpoints. This study underscores the potential distinct biology of cCH as well as the significant unmet need for safe, effective, and well-tolerated preventive treatment. The safety profile of galcanezumab in cCH is consistent with that observed in trials of episodic CH and migraine. TRIAL REGISTRATION: NCT02438826; https://www.clinicaltrials.gov/ct2/show/NCT02438826.

A Multinational Trial of Prasugrel for Sickle Cell Vaso-Occlusive Events.

BACKGROUND: Sickle cell anemia is an inherited blood disorder that is characterized by painful vaso-occlusive crises, for which there are few treatment options. Platelets mediate intercellular adhesion and thrombosis during vaso-occlusion in sickle cell anemia, which suggests a role for antiplatelet agents in modifying disease events. METHODS: Children and adolescents 2 through 17 years of age with sickle cell anemia were randomly assigned to receive oral prasugrel or placebo for 9 to 24 months. The primary end point was the rate of vaso-occlusive crisis, a composite of painful crisis or acute chest syndrome. The secondary end points were the rate of sickle cell-related pain and the intensity of pain, which were assessed daily with the use of pain diaries. RESULTS: A total of 341 patients underwent randomization at 51 sites in 13 countries across the Americas, Europe, Asia, and Africa. The rate of vaso-occlusive crisis events per person-year was 2.30 in the prasugrel group and 2.77 in the placebo group (rate ratio, 0.83; 95% confidence interval, 0.66 to 1.05; P=0.12). There were no significant differences between the groups in the secondary end points of diary-reported events. The safety end points, including the frequency of bleeding events requiring medical intervention, of hemorrhagic and nonhemorrhagic adverse events that occurred while patients were taking prasugrel or placebo, and of discontinuations due to prasugrel or placebo, did not differ significantly between the groups. CONCLUSIONS: Among children and adolescents with sickle cell anemia, the rate of vaso-occlusive crisis was not significantly lower among those who received prasugrel than among those who received placebo. There were no significant between-group differences in the safety findings. (Funded by Daiichi Sankyo and Eli Lilly; ClinicalTrials.gov number, NCT01794000.).

Microbiological Diagnostic Performance of Metagenomic Next-generation Sequencing When Applied to Clinical Practice.

Background: Metagenomic next-generation sequencing (mNGS) was suggested to potentially replace traditional microbiological methodology because of its comprehensiveness. However, clinical experience with application of the test is relatively limited. Methods: From April 2017 to December 2017, 511 specimens were collected, and their retrospective diagnoses were classified into infectious disease (347 [67.9%]), noninfectious disease (119 [23.3%]), and unknown cases (45 [8.8%]). The diagnostic performance of pathogens was compared between mNGS and culture. The effect of antibiotic exposure on detection rate was also assessed. Results: The sensitivity and specificity of mNGS for diagnosing infectious disease were 50.7% and 85.7%, respectively, and these values outperformed those of culture, especially for Mycobacterium tuberculosis (odds ratio [OR], 4 [95% confidence interval {CI}, 1.7-10.8]; P < .01), viruses (mNGS only; P < .01), anaerobes (OR, ∞ [95% CI, 1.71-∞]; P < .01) and fungi (OR, 4.0 [95% CI, 1.6-10.3]; P < .01). Importantly, for mNGS-positive cases where the conventional method was inconclusive, 43 (61%) cases led to diagnosis modification, and 41 (58%) cases were not covered by empirical antibiotics. For cases where viruses were identified, broad-spectrum antibiotics were commonly administered (14/27), and 10 of 27 of these cases were suspected to be inappropriate. Interestingly, the sensitivity of mNGS was superior to that of culture (52.5% vs 34.2%; P < .01) in cases with, but not without, antibiotic exposure. Conclusions: mNGS could yield a higher sensitivity for pathogen identification and is less affected by prior antibiotic exposure, thereby emerging as a promising technology for detecting infectious diseases.

Psychometric Properties of a Modified Version of the Faces Pain Scale-Revised (Modified FPS-R) to Evaluate Worst Pain in Children and Adolescents With Sickle Cell Anemia.

We evaluated psychometric properties (validity, reliability, and responsiveness) of a modified Faces Pain Scale-Revised (FPS-R) in 257 patients with sickle cell anemia (SCA) 7 to below 18 years old in a randomized, multinational clinical study. The modified FPS-R asks patients to report, by daily diary, their worst intraday SCA-related pain. Intraclass correlation coefficient assessed test-retest reliability between month 1 and month 2. Pearson correlations between monthly mean SCA-related pain intensity, activity interference score, analgesic use, and opioid use assessed convergent validity. Responsiveness was assessed with correlations of changes of monthly pain rate or intensity and changes in analgesic use or activity interference score from month 1 to month 9. Intraclass correlation coefficients for pain intensity and pain rate were 0.777 and 0.820, respectively, indicating agreement among stable patients. Moderate associations were shown between mean pain intensity and analgesic use (r=0.39) and opioid use (r=0.44), and between monthly pain rate and analgesic use (r=0.38). Moderate-to-large associations were observed between change in mean pain rate or intensity and changes in analgesic use (r=0.38 to 0.39, both P<0.001) and in activity interference scores (r=0.82 to 0.92, both P<0.001). These results support use of the modified FPS-R across cultures in children and adolescents aged 7 to below 18 years with SCA.

Temporal Biomarker Profiling Reveals Longitudinal Changes in Risk of Death or Myocardial Infarction in Non-ST-Segment Elevation Acute Coronary Syndrome.

BACKGROUND: There are conflicting data on whether changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hs-CRP) concentrations between time points (delta NT-proBNP and hs-CRP) are associated with a change in prognosis. METHODS: We measured NT-proBNP and hs-CRP at 3 time points in 1665 patients with non-ST-segment elevation acute coronary syndrome (NSTEACS). Cox proportional hazards was applied to the delta between temporal measurements to determine the continuous association with cardiovascular events. Effect estimates for delta NT-proBNP and hs-CRP are presented per 40% increase as the basic unit of temporal change. RESULTS: Median NT-proBNP was 370.0 (25th, 75th percentiles, 130.0, 996.0), 340.0 (135.0, 875.0), and 267.0 (111.0, 684.0) ng/L; and median hs-CRP was 4.6 (1.7, 13.1), 1.9 (0.8, 4.5), and 1.8 (0.8, 4.4) mg/L at baseline, 30 days, and 6 months, respectively. The deltas between baseline and 6 months were the most prognostically informative. Every +40% increase of delta NT-proBNP (baseline to 6 months) was associated with a 14% greater risk of cardiovascular death (adjusted hazard ratio (HR) 1.14, 95% CI, 1.03-1.27) and with a 14% greater risk of all-cause death (adjusted HR 1.14, 95% CI, 1.04-1.26), while every +40% increase of delta hs-CRP (baseline to 6 months) was associated with a 9% greater risk of the composite end point (adjusted HR 1.09, 95% CI, 1.02-1.17) and a 10% greater risk of myocardial infarction (adjusted HR 1.10, 95%, CI 1.00-1.20). CONCLUSIONS: Temporal changes in NT-proBNP and hs-CRP are quantitatively associated with future cardiovascular events, supporting their role in dynamic risk stratification of NSTEACS. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00699998.

Successful utilization of an electronic pain diary in a multinational phase 3 interventional study of pediatric sickle cell anemia.

BACKGROUND/AIMS: Patients with sickle cell anemia can experience recurrent pain episodes, which affect quality of life. The reported prevalence of pain is higher in studies using patient diaries than in healthcare facility utilization data. Determining Effects of Platelet Inhibition on Vaso-Occlusive Events was a multinational study that assessed the efficacy and safety of prasugrel in reducing the rate of vaso-occlusive events in children with sickle cell anemia (NCT01794000) and included an electronic patient-reported outcome diary to record pain occurrence. We aimed to capture diary completion rates and compliance in children who used the electronic patient-reported outcome diary during the Determining Effects of Platelet Inhibition on Vaso-Occlusive Events study and examine factors contributing to diary completion rates and compliance. METHODS: Daily electronic patient-reported outcome diary data were collected for up to 9 months in Determining Effects of Platelet Inhibition on Vaso-Occlusive Events participants aged 4 to <18 years in Africa, the Americas, Europe, and the Middle East. The questionnaires were available in 11 languages/dialects for collecting subjective (pain intensity, activity interference) and objective (study drug use, analgesic use, school attendance) data. Pain intensity was measured using the Faces Pain Scale-Revised. Data were entered by participants or caregivers and transferred wirelessly each day to a central database. Diary completion rates were the number of daily diary entries divided by the total number of expected daily diary entries. Percentages of participants who were compliant with the diary (≥80% diary completion) were calculated. RESULTS: A total of 311 participants received a diary; 268 provided diary data through Month 9. Diary completion rates and compliance were high throughout the collection period and across all groups and regions, despite no games being included on the device. For subjective data, the overall completion rate was 94.4%, and 92.6% of participants were compliant. For objective data, the overall completion rate was 93.3%, and 89.7% of participants were compliant. Completion rates and compliance differed significantly by age and region and were higher for 4 to <12 year olds and very much higher for participants from Africa and the Middle East. Caregivers almost always entered data for participants <6 years and rarely entered data for participants ≥12 years. Comparing participant-entered and caregiver-entered data, pain intensity score data were more consistent for 4 to <12 year olds than older children, but pain intensity scores for older children were higher when entered by caregivers. CONCLUSION: With appropriate design, participant training, and sufficient monitoring, an electronic patient-reported outcome diary can capture daily sickle cell-related pain data in large multinational studies. Providing a mechanism for caregiver reporting is particularly valuable for participants <6 years and may also facilitate compliance in older children who experience high levels of pain.

Design of the DOVE (Determining Effects of Platelet Inhibition on Vaso-Occlusive Events) trial: A global Phase 3 double-blind, randomized, placebo-controlled, multicenter study of the efficacy and safety of prasugrel in pediatric patients with sickle cell anemia utilizing a dose titration strategy.

BACKGROUND: Sickle cell disease (SCD) is an inherited blood disorder characterized by painful vaso-occlusive crises (VOC) with limited treatment options, particularly for children. Emerging knowledge of the pathophysiology of SCD suggests antiplatelet therapies may hold promise for treatment of VOC. Multiple small studies have evaluated antiplatelet agents on the frequency of VOC with varying results, but there has not been an adequately powered study to definitively determine the effect of antiplatelet agents on VOC. Prasugrel, a third-generation thienopyridine that irreversibly inhibits platelet activation and aggregation, is approved in adults with acute coronary syndrome managed with percutaneous coronary intervention. PROCEDURE: Determining Effects of Platelet Inhibition on Vaso-Occlusive Events (DOVE) is a double-blind, randomized study with planned enrollment of >220 children from 14 countries across the Americas, Europe, Asia, and Africa, designed to test the hypothesis that prasugrel reduces the rate of VOC in children with sickle cell anemia (SCA) (homozygous hemoglobin S [HbSS] and hemoglobin Sß(0) thalassemia [HbSß(0)]). Secondary study endpoints include reductions in rate and intensity of vaso-occlusive pain as recorded in daily electronic diaries. Safety assessments include incidence of hemorrhagic events requiring medical intervention and treatment-emergent adverse events. DOVE incorporates a dose-titration strategy to reduce potential bleeding risks inherent with antiplatelet therapy while maintaining blinded treatment assignment. CONCLUSIONS: DOVE presents a unique opportunity to determine whether antiplatelet therapy reduces frequency of patient-reported VOC and daily vaso-occlusive pain in a global study of children with SCA.

Prasugrel 5 mg inhibits platelet P-selectin and GPIIb-IIIa expression in very elderly and non elderly: results from the GENERATIONS trial, a pharmacodynamic study in stable CAD patients.

UNLABELLED: Platelet P-selectin and activated glycoprotein IIb-IIIa (GPIIb-IIIa) are markers of platelet activation and mediates platelet aggregation. Prasugrel (Pras) 5 mg may be used in very elderly (VE) acute coronary syndrome (ACS) patients undergoing PCI, but its effect on platelet P-selectin and activated GPIIb-IIIa in those patients is not known. Stable ACS patients, VE (78 ± 5 years, n = 23) and non-elderly (NE) (55 ± 5 years, n = 22) were randomized to Pras (5 or 10 mg) or clopidogrel (Clop) 75 mg during three 12-day periods. Platelet activation markers were measured by flow cytometry on unstimulated or stimulated (adenosine diphosphate (ADP) 20 µM) platelets, before and after each dosing period. RESULTS: At baseline there was no difference in platelet activation markers, either unstimulated or ADP-stimulated, between NE and VE. Pras 5 mg reduced both ADP-stimulated platelet P-selectin and activated GPIIb-IIIa in VE (p < 0.01 for both analyses) and NE (p < 0.001 and p < 0.05, respectively). Clop 75 mg had a similar effect as Pras 5 mg but did not significantly reduce activated GPIIb-IIIa in VE. Prasugrel 10 mg resulted in decreased platelet activation in both age groups compared to Clop 75 mg (p < 0.01). CONCLUSIONS: In VE and NE-patients, Pras 5 mg inhibited platelet P-selectin expression similar to Clop 75 mg and Pras 10 mg. Prasugrel 10 mg inhibited platelet P-selectin expression better than Clop 75 mg. Prasugrel 10 mg and 5 mg, but not Clop 75 mg, significantly inhibited activated GPIIb-IIIa in VE. This platelet reactivity data support the use of Pras 5 mg for VE patients.

Hydrazine-hydrothermal synthesis and characterization of the two new quaternary thioantimonates(III) BaAgSbS3 and BaAgSbS3·H2O.

The two new quaternary thioantimonates(III) BaAgSbS3 (1) and BaAgSbS3·H2O (2) have been synthesized through a hydrazine-hydrothermal method at low temperature. Compound 1 possesses a two-dimensional (2D) layer structure, while compound 2 features a three-dimensional (3D) channel framework. The optical band gaps of 1 and 2 are approximately 2.2 and 2.4 eV, respectively. Our results clearly indicated that the hydrazine-hydrothermal method could offer exciting opportunities for exploring novel multinary chalcogenides with diverse crystal structures and interesting physical properties.

Prasugrel in children with sickle cell disease: pharmacokinetic and pharmacodynamic data from an open-label, adaptive-design, dose-ranging study.

INTRODUCTION: This phase 2 study was designed to characterize the relationship among prasugrel dose, prasugrel's active metabolite (Pras-AM), and platelet inhibition while evaluating safety in children with sickle cell disease. It was open-label, multicenter, adaptive design, dose ranging, and conducted in 2 parts. Part A: Patients received escalating single doses leading to corresponding increases in Pras-AM exposure and VerifyNow®P2Y12 (VN) platelet inhibition and decreases in VNP2Y12 reaction units and vasodilator-stimulated phosphoprotein platelet reactivity index. Part B: Patients were assigned daily doses (0.06, 0.08, and 0.12 mg/kg) based on VN pharmacodynamic measurements at the start of 2 dosing periods, each 14±4 days. Platelet inhibition was significantly higher at 0.12 mg/kg (56.3%±7.4%; least squares mean±SE) compared with 0.06 mg/kg (33.8%±7.4%) or 0.08 mg/kg (37.9%±5.6%). Patients receiving 0.12 mg/kg achieved ≥30% platelet inhibition; only 1 patient receiving 0.06 mg/kg exceeded 60% platelet inhibition. High interpatient variability in response to prasugrel and the small range of exposures precluded rigorous characterization of the relationship among dose, Pras-AM, and platelet inhibition. SAFETY: No hemorrhagic events occurred in Part A; 3 occurred in Part B, all mild and self-limited. CONCLUSIONS: Most children with sickle cell disease may achieve clinically relevant platelet inhibition with titration of daily-dose prasugrel.

The effect of prasugrel on ADP-stimulated markers of platelet activation in patients with sickle cell disease.

Platelets of patients with sickle cell disease (SCD) show evidence of mild activation in the non-crisis steady state and greater activation during vaso-occlusive crises (VOC). Prasugrel, a potent inhibitor of ADP-mediated platelet activation and aggregation, may be useful in attenuating VOC. We compared platelet responses to ADP stimulation in patients with SCD and healthy subjects before and after treatment with prasugrel. In a phase 1 study, platelet biomarker levels were assessed in 12 adult patients with SCD and 13 healthy subjects before and after 12 ± 2 days of 5.0 or 7.5 mg/day prasugrel. The following were determined in whole blood samples stimulated with 20 µM ADP: (i) percentages of monocytes and neutrophils with adherent platelets (cell-platelet aggregates); (ii) the relative number (mass) of platelets associated with each monocyte and neutrophil as reported by CD61 mean fluorescence intensity (MFI) of the monocyte-platelet and neutrophil-platelet aggregates; (iii) the percentages of platelets positive for surface expression of CD40 ligand (CD40L), P-selectin (CD62p) and activated glycoprotein IIb-IIIa (GPIIb-IIIa); and (iv) the percentages of platelets and monocyte-platelet aggregates positive for surface tissue factor (TF) expression. At baseline, there were no significant differences between cohorts in the percentages of platelets expressing activation biomarkers. Following 12 days of prasugrel administration, the percentages of platelets expressing activation biomarkers following ADP stimulation were reduced in both cohorts, and there were no significant differences between groups. Both patients with SCD and healthy subjects had significant reductions in the monocyte-platelet and neutrophil-platelet aggregate MFI and the percentage of platelets expressing P-selectin and activated GPIIb-IIIa (all p < 0.05). Healthy subjects also had significant reductions in monocyte-platelet aggregate percentages (p = 0.004), neutrophil-platelet aggregate percentages (p = 0.011) and the percentage of CD40L-positive platelets (p = 0.044) that were not observed in patients with SCD. Prasugrel administration to SCD patients attenuates ex vivo ADP-stimulated platelet activation as measured by the percentage of platelets positive for P-selectin and GPIIb-IIIa, thus reducing the proportion of platelets that may participate in aggregates. Furthermore, prasugrel decreases ex vivo ADP-stimulated platelet aggregation with monocytes and neutrophils as measured by the monocyte-platelet and neutrophil-platelet aggregate MFI. This implies that in the presence of prasugrel, fewer platelets adhere to monocytes and neutrophils, which may result in reducing cell-platelet aggregate size. Therefore, reduced platelet reactivity and decreased size of leukocyte-platelet aggregates suggest additional mechanisms by which prasugrel may provide benefit to patients with SCD and support further investigation of possible therapeutic benefits of prasugrel in this population.

[Analysis of pathogen spectrum and resistance of clinical common organisms causing bloodstream infections, hospital-acquired pneumonia and intra-abdominal infections from thirteen teaching hospitals in 2013].

OBJECTIVE: To investigate the spectrum and antimicrobial resistance of major pathogensthat causing nosocomial infections in China, 2013. METHODS: Nosocomial cases as well as pathogens causing bloodstream infections (BSI), hospital-acquired pneumonia (HAP) and intra-abdominal infections (IAI) from 13 teaching hospital around China were collected. The minimum inhibitory concentrations (MICs) were determined by the agar dilution method. The CLSI M100-S23 criteria were used for interpretation. RESULTS: Of all cases, 1 022 cases were from BSI, 683 from HAP and 674 from IAI.Escherichia coli and Klebsiella pneumoniae were the most prevalent pathogens causing BSI and IAI while Acinetobacter baumanii (34.6%) and Pseudomonas aeruginosa were dominated in HAP. Tigecycline, imipenem and meropenem exhibited high potency against Enterobacteriaceae and the susceptibilities rates were 95.6%, 94.2%and 95.2% respectively. Enterobacteriaceae demonstrated high resistance against cephalosporins (52.3%) and fluoroquinolones (38.9%) but were susceptible to ß-lactam+inhibitor. Of all the Enterobacteriaceae, 30.5% were ESBLs positive and 4.3% were carbapenem resistant. Acinetobacter baumanii showed low susceptibilities to the microbial agents except for tigecycline (90.5%) and colistin (100%). The rate of carbapenem resistant Acinetobacter baumanii was 76.6%. Amikacin, ciprofloxacin, cefepime and piperacillin/tazobactam showed high antibacterial activity against Pseudomonas aeruginosa with susceptible rate 88.5%, 77.6%, 72.7% and 64.5% respectively. The resistant rate to imipenem and meropenem were 42.1% and 32.2%. All Staphylococcus aureus (166 strains) were susceptible to tigecycline, linezolid, daptomycin and glycopeptides. MRSA accounted for 46.9% of all the Staphylococcus aureus. The prevalence of MRSA in IAI (55.2%) and HAP (54.4%) were higher that that in BSI (35.0%). No Enterococcus strains were found resistant to tigecycline, linezolid and daptomycin. VRE was found in Enterococcus faecium, accounting for 1.9% of all Enterococcus faecium strains. CONCLUSIONS: Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa are the most common pathogens causing nosocomial infections. Nosocomial pathogens showed high susceptibilities against tigecycline. For ESBLs-producing Enterobacteriaceae strains, ß-lactam+Inhibitor show high antibacterial activities. Vancomycin, teicoplanin and linezolid exhibit high potency to Staphylococcus aureus and Enterococcus.

Higher body weight patients on clopidogrel maintenance therapy have lower active metabolite concentrations, lower levels of platelet inhibition, and higher rates of poor responders than low body weight patients.

Body weight is a predictor of clopidogrel response. However, no prospective studies have compared pharmacodynamic (PD) and pharmacokinetic (PK) data based on body weight. We compared PD and PK effects of clopidogrel 75 mg in low body weight (LBW, <60 kg) and higher body weight (HBW, ≥60 kg) patients with stable coronary artery disease. LBW (n = 34, 56.4 ± 3.7 kg) and HBW (n = 38, 84.7 ± 14.9 kg) aspirin-treated patients received clopidogrel 75 mg for 10-14 days. The area under the concentration-time curve of active metabolite (Clop-AM) calculated through the last quantifiable concentration up to 4 h postdose, AUC(0-tlast), was calculated by noncompartmental methods. Light transmission aggregometry (LTA) (maximum platelet aggregation and inhibition of platelet aggregation to 20 µM adenosine diphosphate (ADP), and residual platelet aggregation to 5 µM ADP), VerifyNow(®) P2Y12 reaction units (PRU), and vasodilator-associated stimulated phosphoprotein phosphorylation platelet reactivity index (VASP-PRI) were performed. Mean AUC(0-tlast) was lower in HBW than LBW patients: 12.8 versus 17.9 ng h/mL. HBW patients had higher platelet reactivity as measured by LTA (all p ≤ 0.01), PRU (207 ± 68 vs. 152 ± 57, p < 0.001), and VASP-PRI (56 ± 18 vs. 39 ± 17, p < 0.001). More HBW patients exhibited high on-treatment platelet reactivity (HPR) using PRU (35 vs. 9%) and VASP-PRI (65 vs. 27%). Body weight correlated with PRU and VASP-PRI (both p < 0.001), and inversely with log transformed AUC(0-tlast) (p < 0.001). In conclusion, HBW patients had lower levels of Clop-AM, and higher platelet reactivity and rates of HPR than LBW subjects, contributing to their suboptimal response to clopidogrel.

[An analysis of clinical characteristics, etiologies and prognosis of 218 patients with infective endocarditis].

OBJECTIVE: To describe the profile of patients with infective endocarditis (IE) and assess prognostic factors of IE. METHODS: Clinical and etiology data of 218 patients with IE were collected retrospectively from January 2011 to January 2013. The distribution and antimicrobial susceptibilities of pathogens causing IE were evaluated. Prognostic factors associated with IE were determined by univariate and multivariate regression analysis. RESULTS: There were 148 men and 70 women with age of (46.0 ± 14.6) years. Ninety-five (43.6%) of them had heart diseases, including 72 cases (33.0%) of congenital heart disease and 23 cases (10.6%) of chronic rheumatic heart disease. Vegetations were detected by echocardiography in 171 (78.4%) patients. Microorganisms causing IE were identified in 84 cases (38.5%) cases. Streptococcus viridans was the dominant pathogen, accounted for 63.1% of all the pathogens, followed by Staphylococcus (13.1%) and Enterococcus (4.8%). Totally 7/11 Streptococcus viridans was susceptible to penicillin, while 100% susceptible to the third and fourth generation cephalosporins, vancomycin and linezolid. One hundred and eighty cases underwent operations. The in-hospital mortality rate of IE was 3.2%. In univariate regression, health care-associated infection, prosthetic valve, anemia and chest symptoms (distress or pain) were related to the increased risk of mortality in patients with IE, while surgery appeared to be a protective factor. In the logistic regression model, the variables significantly associated with IE prognosis were health care-associated infection (OR = 17.03, 95%CI 1.76-164.75, P = 0.014) and anemia (Hb < 90 g/L) (OR = 13.47, 95%CI 2.46-73.60, P = 0.003) and surgery treatment (OR = 0.17, 95%CI 0.03-0.97, P = 0.047). CONCLUSIONS: Although Streptococcus viridans is the most common pathogen causing IE, the pathogens of IE become versatile. The antibacterial activity of penicillin against Streptococcus viridans is low. Health care-associated infection and anemia are risk factors of IE prognosis, while surgery treatment is a protective factor of severe IE.

Accurate etiological diagnosis of Mycoplasma hominis mediastinitis in immunocompetent patients using metagenomic next-generation sequencing: a case series and literature review.

Background: As a culture-independent method, metagenomic next-generation sequencing (mNGS) is widely used in microbiological diagnosis with advantages in identifying potential pathogens, guiding antibiotic therapy, and improving clinical prognosis, especially in culture-negative cases. Mycoplasma hominis (M. hominis) mediastinitis is a rare and severe disease for which etiological diagnosis is important but challenging. The application of mNGS in the etiological diagnosis of mediastinitis has seldom been studied. Methods: By searching the electronic medical history retrieval system with "Mycoplasma hominis" and "mediastinitis", seven patients diagnosed with M. hominis mediastinitis were reviewed in Zhongshan Hospital, Fudan University, Shanghai from 9 December 2020 to 14 February 2023. Microbiological cultures and mNGS were conducted for blood, abscess, and/or mediastinal fluid. Adjustment of the antibiotic therapy due to mNGS was assessed. A literature review was conducted in the PubMed database beginning in 1970 for M. hominis infection and mediastinitis. Results: For the seven patients, cultures of blood, abscess, and mediastinal fluid were negative whereas mNGS identified M. hominis in serum, abscess, and/or mediastinal fluid and was used to guide specific antibiotic therapy. The stringent mapped reads number of genera (SMRNG), stringent mapped reads number of species (SMRN), and coverage rate of M. hominis detection by mNGS were significantly higher in body fluid (abscess or mediastinal fluid) than in serum. All seven patients had underlying heart diseases and underwent previous cardiac surgery. The most common symptoms were fever and sternal pain. After detection of M. hominis, antibiotics were adjusted to quinolones or doxycycline except for one patient, whose diagnosis was clarified after death. Two patients died. Literature review since 1970 identified 30 cases of extra-genital infection caused by M. hominis. Including our seven new cases, 2 (5.4%) were neonates and 35 (94.6%) were adults. Thirty (81.1%) cases were postoperative infection and 15 (40.5%) had implanted devices. Five patients (13.5%) died. Conclusions: mNGS might be a promising technology in the detection of fastidious pathogens such as M. hominis. Accurate etiological diagnosis by mNGS could guide antibiotic therapy and facilitate clinical management.