Alteco endotoxin hemoadsorption in Gram-negative septic shock patients

Results:This study was terminated early as interim analysis showed a low probability of significant findings. No significant difference was noted between the two groups with respect to change in SOFA score, vasopressor score, PFR, LOS, and 28-day mortality. Side-effect was minimal.Conclusions:We could not identify any clinical benefit on the addition of Alteco endotoxin hemoadsorption to conventional therapy in patients who suffered from intra-abdominal sepsis with shock. The side effect profile of this novel device was acceptable.     

Maternal colonization and early-onset neonatal bacterial sepsis in the Gambia,West Africa: a genomic analysis of vertical transmission

ObjectivesTo define bacterial aetiology of neonatal sepsis and estimate the prevalence of neonatal infection from maternal genital tract bacterial carriage among mother-newborn pairs.MethodsWe carried out a cross-sectional study of newborns with clinical sepsis admitted to three hospitals in the Gambia neonatal wards. Neonatal blood cultures and maternal genital swabs were obtained at recruitment. We used whole-genome sequencing to explore vertical transmission for neonates with microbiologically confirmed bloodstream infection by comparing phenotypically-matched paired neonatal blood cultures and maternal genital tract bacterial isolates.ResultsWe enrolled 203 maternal-newborn pairs. Two-thirds (67%; 137/203) of neonates presented with early-onset sepsis (days 0–6 after birth) of which 26% (36/137) were because of a clinically-significant bacterial pathogen. Blood culture isolates from newborns with early-onset sepsis because of Staphylococcus aureus (n = 5), Klebsiella pneumonia (n = 2), and Enterococcus faecalis (n = 1), phenotypically matched their maternal genital tract isolates. Pairwise single-nucleotide variants comparisons showed differences of 12 to 52 single-nucleotide variants only between maternal and newborn S. aureus isolates, presumably representing vertical transmission with a transmission rate of 14% (5/36).ConclusionsWe found a low prevalence of vertical transmission of maternal genital tract colonization in maternal-newborn pairs for early-onset neonatal sepsis in the West African context. Identifying infection acquisition pathways among newborns is essential to prioritize preventive interventions, which could be targeted at the mother or infection control in the hospital environment, depending on the major pathways of transmission.     

Endotoxin removal from whole blood by a novel adsorption resin: efficiency and hemocompatibility

The structural component of Gram- bacteria, endotoxin (ET), induces the release of endogenous mediators of sepsis. Attempts to remove these downstream molecules in vivo, have not improved survival. However, extracorporeal strategies such as continuous renal replacement therapy or therapeutic plasmapheresis have shown benefit. We are presenting an affinity-based extracorporeal technology for the removal of ET from whole blood. The small-scale device contains an adsorbent that removed 75% of ET present in whole blood. This affinity resin displayed good hemocompatibility regarding the coagulation pathway. Minimal platelet, neutrophil and complement activation were observed. There was also no evidence of consumption of coagulation factors or cell loss. In as much as ET participates in both the inflammatory and coagulation abnormalities in sepsis, this method represents an efficient and hemocompatible way to remove ET from whole blood, which, in an extracorporeal setting, may improve the outcome of sepsis.     

Experimental Validation of a Theoretical Model of Cytokine Capture Using a Hemoadsorption Device

Sepsis, a systemic inflammatory response in the presence of an infection, is characterized by overproduction of inflammatory mediators called cytokines. Removal of these cytokines using an extracorporeal hemoadsorption device is a potential therapy for sepsis. We are developing a cytokine adsorption device (CAD) filled with microporous polymer beads and have previously published a mathematical model which predicts the time course of cytokine removal by the device. The goal of this study was to show that the model can experimentally predict the rate of cytokine capture associated with key design and operational parameters of the CAD. We spiked IL-6, IL-10, and TNF into horse serum and perfused it through an appropriately scaled-down CAD and measured the change in concentration of the cytokines over time. These data were fit to the mathematical model to determine a single model parameter, Γ _i , which is only a function of the cytokine–polymer interaction and the cytokine effective diffusion coefficient in the porous matrix. We compared Γ _i values, which by definition should not change between experiments. Our results indicate that the Γ _i value for a specific cytokine was statistically independent of all other parameters in the model, including initial cytokine concentration, flow rate, serum reservoir volume, CAD size, and bead size. Our results also indicate that competitive adsorption of cytokines and other middle-molecular weight proteins, which is neglected in the model, does not affect the rate of removal of a given cytokine. The model of cytokine capture in the CAD developed in this study will be integrated with a systems model of sepsis to simulate the progression of sepsis in humans and to develop a therapeutic CAD design and intervention protocol that improves patient outcomes in sepsis.     

Use of a novel hemoadsorption device for cytokine removal as adjuvant therapy in a patient with septic shock with multi-organ dysfunction: A case study

CytoSorb^® (CytoSorbents Corporation, USA) is a novel sorbent hemoadsorption device for cytokine removal. The aim of this study was to examine the clinical use of CytoSorb^® in the management of patient with septic shock. We used this device as an adjuvant to stabilize a young patient with multi-organ failure and severe sepsis with septic shock. A 36-year-old female patient was hospitalized with the complaints of malaise, general body ache, and breathing difficulty and had a medical history of diabetes mellitus type II, hypertension, obstructive sleep apnea, hypothyroidism and morbid obesity. She was diagnosed to have septic shock with multi-organ dysfunction (MODS) and a low perfusion state. CytoSorb^® hemoadsorption column was used as an attempt at blood purification. Acute physiology and chronic health evaluation score, MODS score, and sequential organ failure assessment score were measured before and after the device application. CytoSorb application as an adjuvant therapy could be considered in septic shock.     

Pharmacokinetic/pharmacodynamic considerations for new and current therapeutic drugs for uncomplicated gonorrhoea—challenges and opportunities

BackgroundIncreasing multidrug resistance rates in Neisseria gonorrhoeae have raised concerns and an urgent call for new antibiotics for treatment of gonorrhoea. Several decades of subdued drug development in this field and the recent failures of two new antibiotics to show non-inferiority compared with the current first-line antibiotics ceftriaxone plus azithromycin highlight the need for improved preclinical tools to predict clinical outcome of new drugs in the development process.ObjectivesTo summarize current pharmacokinetic/pharmacodynamic (PK/PD) knowledge and dose-finding strategies for antibiotics against gonorrhoea.SourcesLiterature review of published papers and discussions by global experts at a special workshop on this topic.ContentWe review current knowledge of gonococcal specific PK/PD principles and provide an update on new in vitro and in vivo models to correlate drug exposure with clinical outcome, and identify challenges and gaps in gonococcal therapeutic research.ImplicationsIdentifying the ideal antimicrobial agent and dose for treating uncomplicated urogenital and pharyngeal gonococcal disease requires appropriate validated non-clinical PK/PD models. Recent advances in adapting in vitro and in vivo models for use in gonorrhoea are an important step for enabling the development of new drugs with reduced risk of failure in Phase 3 clinical development and diminish the risk of emergence of resistance.     

Positive Maternal C-Reactive Protein Predicts Neonatal Sepsis

Purpose

To evaluate the diagnostic performance of maternal inflammatory marker: C-reactive protein (CRP) in predicting early onset neonatal sepsis (that occurring within 72 hours after birth).

Materials and Methods

126 low birth weight newborns (gestation 32±3.2 wk, birth weight 1887±623 g) and their mothers were included. Neonates were divided into sepsis group (n=51) including both proven (positive blood culture) and suspected (negative blood culture but with more than 3 abnormal clinical signs), and controls (n=75). Mothers were subgrouped into CRP positive ≥1.22 mg/dL (n=48) and CRP negative <1.22 mg/dL (n=78) group, determined by Receiver Operating Characteristic curves, and odds ratio was calculated for neonatal sepsis according to maternal condition.

Results

Maternal CRP was significantly higher in neonatal sepsis group than in control (3.55±2.69 vs. 0.48±0.31 mg/dL, p=0.0001). Maternal CRP (cutoff value >1.22 mg/dL) had sensitivity 71% and specificity 84% for predicting neonatal sepsis. Maternal CRP positive group had more neonatal sepsis than CRP negative group (71% vs. 29%, p<0.001). Odds ratio of neonatal sepsis in maternal CRP positive group versus CRP negative group was 10.68 (95% confidence interval: 4.313-26.428, p<0.001).

Conclusion

The risk of early onset neonatal sepsis significantly increased in the case of positive maternal CRP (≥1.22 mg/dL). In newborn of CRP positive mother, the clinician may be alerted to earlier evaluation for possible neonatal infection prior to development of sepsis.     

Antibiotic prescribing practices in three neonatology units in Kigali,Rwanda. – an observational study

IntroductionThere is limited published data on antibiotic use in neonatal units in resource-poor settings.ObjectivesThis study sought to describe antibiotic prescribing practices in three neonatology units in Kigali, Rwanda.MethodsA multi-center, cross-sectional study conducted in two tertiary and one urban district hospital in Kigali, Rwanda. Participants were neonates admitted in neonatology who received a course of antibiotics during their admission. Data collected included risk factors for neonatal sepsis, clinical signs, symptoms, investigations for neonatal sepsis, antibiotics prescribed, and the number of deaths in the included cohort.Results126 neonates were enrolled with 42 from each site. Prematurity (38%) followed by membrane rupture more than 18 hours (25%) were the main risk factors for neonatal sepsis. Ampicillin and Gentamicin (85%) were the most commonly used first-line antibiotics for suspected neonatal sepsis. Most neonates (87%) did not receive a second-line antibiotic. Cefotaxime (11%), was the most commonly used second-line antibiotic. The median duration of antibiotic use was four days in all surviving neonates (m=113). In neonates with negative blood culture and normal C-reactive protein (CRP), the median duration of antibiotics was 3.5 days; and for neonates, with positive blood cultures, the median duration was 11 days. Thirteen infants died (10%) at all three sites, with no significant difference between the sites.ConclusionThe median antibiotic duration for neonates with normal lab results exceeded the recommended duration mandated by the national neonatal protocol. We recommend the development of antibiotic stewardship programs in neonatal units in Rwanda to prevent the adverse effects which may be caused by inappropriate or excessive use of antibiotics.     

Catheter-Related Brevibacterium casei Bloodstream Infection in a Child with Aplastic Anaemia

Brevibacteria are a part of the normal skin flora and may be dismissed in blood cultures as contaminants. They have been reported as opportunistic pathogens in immunocompromised patients. We report a catheter-related bloodstream infection with Brevibacterium casei in a 6-year-old child with aplastic anaemia. Treatment with appropriate antibiotics along with the removal of the catheter resulted in complete cure in our patient.     

An off-the-shelf plasma-based material to prevent pacemaker pocket infection

Bacterial infection of subcutaneous “pockets” housing cardiovascular implantable electronic devices is a significant clinical complication. In this study, pacemakers encapsulated in a blood plasma-based material (PBM) composited with antibiotics were investigated for use as prophylactics against such infections. PBMs, which are made from pooled allogeneic plasma and platelets, are off-the-shelf biomaterials that can be manufactured in the form of complex 3D shapes, extrudable putties, or injectable pastes. In vitro studies with PBM pastes formulated with rifampicin and minocycline demonstrated antibiotic release over 6 days, activity against Escherichia coli, and reduced cytotoxic effects of the antibiotics on fibroblasts. The materials were also evaluated in vivo in a rabbit model in which pacemaker pockets were inoculated with methicillin-resistant Staphylococcus aureus (S. aureus) strain and examined 1 week later. The pockets containing the pacemaker plus S. aureus were grossly purulent and culture positive, whereas pockets into which PBM with antibiotics were injected around the pacemaker were free of purulence and culture negative (p < 0.001). None of the pockets into which PBM without antibiotics were placed demonstrated purulence, but 60% were culture positive. These results demonstrate the potential of PBMs to deliver antibiotics to diminish the incidence of pocket infections for pacemakers and other implantable devices.     

Streptococcus gallolyticus – A potentially neglected pathogen causing neonatal sepsis not covered by routine group B streptococcus screening

We report 4 cases of neonatal sepsis caused by Streptococcus gallolyticus. The clinical course was quite similar to early-and late-onset group B streptococcus disease. None of the mothers had group B streptococcus (GBS) colonization on prenatal screening nor received intrapartum antibiotics. We proposed the sporadic distribution of S. gallolyticus sepsis among neonates was partly due to relatively low colonization rate in adults compared with GBS. Species determination of S. gallolyticus may not be available using conventional microbiological methods and may contribute to underestimation or misclassification. In our series, we highlighted the importance of S. gallolyticus as an important pathogen in neonatal sepsis deserving further surveillance.     

Immune responses of channel catfish following the stimulation of three recombinant flagellins of Yersinia ruckeri in vitro and in vivo

Innate immunity is initiated depending on the recognition of certain protein receptors termed pattern recognition receptors (PRRs) of pathogen-associated molecular patterns (PAMPs) to protect the host from various invading pathogens. As one of the most powerful PAMPs, flagellin is the major structural component of the flagellum that provides the main force for bacterial motility in flagellated microorganisms. The genome of the Y. ruckeri strain SC09 contains three flagellin genes, which encode the flagellins FlaA, FlaB and FlaC, respectively. In this study, we produced the three full-length recombinant flagellins—i.e., rFlaA, rFlaB and rFlaC—from the Y. ruckeri strain SC09 for the first time and then compared the host cell responses to rFlaA, rFlaB and rFlaC using channel catfish cultured head kidney monocytes/macrophages in vitro. Moreover, the time-dependent modulation of the nine genes expression of primary kidneys injected with rFlaC was also detected by qPCR. We found that rFlaA, rFlaB and rFlaC all can stimulate the production of some pro-inflammatory cytokines, such as IL1-β1, TNFα, IL8, iNOS1 and Hepcidin. In addition, the expression of TLR5M, TLR5S, NF-κB and MHC II β was all increased after channel catfish cultured head kidney monocytes/macrophages were stimulated by the three recombinant flagellins. Importantly, rFlaC stimulated the highest expression of all the genes mentioned above compared with that of rFlaB and rFlaA and enhanced the expression of the nine above-mentioned genes in vivo. Our study lays the foundation for the effect of flagellin on immune responses, suggesting that flagellin may be a useful immune adjuvant or stimulant in the aquaculture field.     

Efficacy of EBL-1003 (apramycin) against Acinetobacter baumannii lung infections in mice

ObjectivesNovel therapeutics are urgently required for the treatment of carbapenem-resistant Acinetobacter baumannii (CRAB) causing critical infections with high mortality. Here we assessed the therapeutic potential of the clinical-stage drug candidate EBL-1003 (crystalline free base of apramycin) in the treatment of CRAB lung infections.MethodsThe genotypic and phenotypic susceptibility of CRAB clinical isolates to aminoglycosides and colistin was assessed by database mining and broth microdilution. The therapeutic potential was assessed by target attainment simulations on the basis of time–kill kinetics, a murine lung infection model, comparative pharmacokinetic analysis in plasma, epithelial lining fluid (ELF) and lung tissue, and pharmacokinetic/pharmacodynamic (PKPD) modelling.ResultsResistance gene annotations of 5451 CRAB genomes deposited in the National Database of Antibiotic Resistant Organisms (NDARO) suggested >99.9% of genotypic susceptibility to apramycin. Low susceptibility to standard-of-care aminoglycosides and high susceptibility to EBL-1003 were confirmed by antimicrobial susceptibility testing of 100 A. baumannii isolates. Time–kill experiments and a mouse lung infection model with the extremely drug-resistant CRAB strain AR Bank #0282 resulted in rapid 4-log CFU reduction both in vitro and in vivo. A single dose of 125 mg/kg EBL-1003 in CRAB-infected mice resulted in an AUC of 339 h × μg/mL in plasma and 299 h × μg/mL in ELF, suggesting a lung penetration of 88%. PKPD simulations suggested a previously predicted dose of 30 mg/kg in patients (creatinine clearance (CLCr) = 80 mL/min) to result in >99% probability of –2 log target attainment for MICs up to 16 μg/mL.ConclusionsThis study provides proof of concept for the efficacy of EBL-1003 in the treatment of CRAB lung infections. Broad in vitro coverage, rapid killing, potent in vivo efficacy, and a high probability of target attainment render EBL-1003 a strong therapeutic candidate for a priority pathogen for which treatment options are very limited.     

Amphiphilic dendritic derivatives as nanocarriers for the targeted delivery of antimalarial drugs

It can be foreseen that in a future scenario of malaria eradication, a varied armamentarium will be required, including strategies for the targeted administration of antimalarial compounds. The development of nanovectors capable of encapsulating drugs and of delivering them to Plasmodium-infected cells with high specificity and efficacy and at an affordable cost is of particular interest. With this objective, dendritic derivatives based on 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) and Pluronic^® polymers have been herein explored. Four different dendritic derivatives have been tested for their capacity to encapsulate the antimalarial drugs chloroquine (CQ) and primaquine (PQ), their specific targeting to Plasmodium-infected red blood cells (pRBCs), and their antimalarial activity in vitro against the human pathogen Plasmodium falciparum and in vivo against the rodent malaria species Plasmodium yoelii. The results obtained have allowed the identification of two dendritic derivatives exhibiting specific targeting to pRBCs vs. non-infected RBCs, which reduce the in vitro IC₅₀ of CQ and PQ by ca. 3- and 4-fold down to 4.0 nm and 1.1 μm, respectively. This work on the application of dendritic derivatives to antimalarial targeted drug delivery opens the way for the use of this new type of chemicals in future malaria eradication programs.     

Improved implant osseointegration of a nanostructured titanium surface via mediation of macrophage polarization

The use of endosseous implanted materials is often limited by undesirable effects that may be due to macrophage-related inflammation. The purpose of this study was to fabricate a nanostructured surface on a titanium implant to regulate the macrophage inflammatory response and improve the performance of the implant. Anodization at 5 and 20 V as well as UV irradiation were used to generate hydrophilic, nanostructured TiO₂ surfaces (denoted as NT5 and NT20, respectively). Their surface characteristics and in vivo osseointegration as well as the inflammatory response they elicit were analyzed. In addition, the behavior of macrophages in vitro was evaluated. Although the in vitro osteogenic activity on the two surfaces was similar, the NT5 surface was associated with more bone formation, less inflammation, and a reduced CD68⁺ macrophage distribution in vivo compared to the NT20 and polished Ti surfaces. Consistently, further experiments revealed that the NT5 surface induced healing-associated M2 polarization in vitro and in vivo. By contrast, the NT20 surface promoted the pro-inflammatory M1 polarization, which could further impair bone regeneration. The results demonstrate the dominant role of macrophage-related inflammation in bone healing around implants and that surface nanotopography can be designed to have an immune-regulating effect in support of the success of implants.     

Adenosine infusion attenuates soluble RAGE in endotoxin‐induced inflammation in human volunteers

Aim: To evaluate possible anti‐inflammatory effects of pre‐treatment with adenosine in a human experimental inflammatory model. Methods: The study design was double‐blind, crossover, placebo‐controlled and randomized. In the Intensive Care Unit of a university hospital, 16 healthy male volunteers were treated for 5.5 h with infusions of adenosine 40 μg kg^?1 min^?1 or placebo. Thirty minutes after the start of adenosine or placebo, 2 ng kg^?1E‐Coli endotoxin was administered. Heart rate, body temperature, blood pressure, plasma cytokines (TNF‐α, IL‐6 and IL‐10), soluble RAGE and resistin, exhaled nitric oxide and nitrite/nitrate in urine were determined. Results: Endotoxin elicited the expected clinical signs of an inflammatory reaction (tachycardia, fever) and led to prominent release of the cytokines studied (P < 0.001). Resistin in plasma increased after endotoxin (P < 0.001). After placebo treatment, soluble RAGE (sRAGE) in plasma increased 5 h after the endotoxin challenge (P < 0.001) but not after adenosine. After placebo, orally exhaled NO increased with a peak at 4 h (P < 0.001), although there was no statistically significant difference between the two treatments. Nitrite/nitrate in urine (n = 11) did not differ between adenosine and placebo treatments. Conclusion: In conclusion, adenosine infusion starting before endotoxin challenge in humans attenuated sRAGE significantly but otherwise had no clear anti‐inflammatory effect. Adenosine as a potential anti‐inflammatory treatment in humans needs further study, including use of higher doses. The mechanism underlying the effect of adenosines on sRAGE remains unknown.     

Lanthanide-based nanocrystals as dual-modal probes for SPECT and X-ray CT imaging

Applications of lanthanide-based nanoparticles for bioimaging have attracted increasing attention. Herein, small size PEG-EuOF:¹⁵³Sm nanocrystals (∼5 nm) (PEG = poly(ethylene glycol)bis(carboxymethyl)ether) combined with the radioactive and X-ray absorption properties were synthesized. The distribution of the PEG-EuOF nanocrystals in living animals was studied by ex vivo radioassay, inductively coupled plasma-atomic emission spectrum (ICP-AES) analysis and in vivo SPECT imaging, which indicated that the small size PEG-EuOF:¹⁵³Sm had long blood retention time (blood half-life (t_1/2) reach to 4.65 h) and were eliminated significantly through biliary/gastrointestinal pathway in vivo. Meanwhile, benefiting from the high attenuation ability of Eu, the small size PEG-EuOF was successfully applied for lymph node CT imaging, extending the bio-applications of these small nanocrystals. The results of cytotoxicity and in vivo toxicity also showed that the PEG-EuOF nanocrystals have relatively low toxicity, which suggest their safety for in vivo imaging. The studies provide preliminary validation for the use of PEG-EuOF nanocrystals for in vivo bioimaging applications.     

Ribosomal RNA-based panbacterial polymerase chain reaction for rapid diagnosis of septicaemia in Intensive Care Unit patients

Early diagnosis and treatment of sepsis by appropriate antibiotics is of utmost importance. Therefore, we evaluated 16S rRNA panbacterial polymerase chain reaction (PCR) for rapid diagnosis of sepsis in 49 adult patients in Intensive Care Units (ICUs) and compared it with an automated blood culture. 8 ml of 10 ml blood collected was inoculated into BACTEC® aerobic bottle and the remaining 2 ml was used for DNA extraction and PCR. 109 of 115 (93%) episodes of suspected sepsis showed concordant results between automated culture and PCR. Six episodes were positive by PCR only. Panbacterial PCR reduces turnaround time with rapid differentiation between systemic inflammatory response syndrome and sepsis.     

Compliance with severe sepsis bundles and its effect on patient outcomes of severe community-acquired pneumonia in a limited resources country

Introduction

Validation of compliance with severe sepsis bundles is still needed. The purpose of this study was to determine compliance and its outcomes in severe community-acquired pneumonia (CAP) patients in a limited resources country.

Material and methods

A prospective cohort study of 212 severe CAP patients was carried out. The implementation programme was organized into two continuous phases. The primary outcomes were compliance and hospital mortality.

Results

Compliance with administration of antibiotics and vasopressors as well as plateau pressure on average < 30 cm H₂O was high in both groups. In the bundles group, patients received more serum lactate monitoring (62.3% vs. 11.3%), more blood cultures (47.1% vs. 24.5%), more fluid resuscitation (63.2% vs. 26.4%) and volumes infused (1319.8 ±1107.4 ml vs. 461.9 ±799.3 ml), more inotropic dobutamine and/or packed red blood cells (21.7% vs. 10.0%), more low-dose steroids (56.5% vs. 15.0%), and more glucose control (51.9% vs. 6.6%) compared with such patients in the control group. The rates of total compliance with 6-hour, 24-hour, and 6/24-hour bundles in the prospective period were 47.1%, 51.9%, and 42.5%, respectively. Hospital mortality was reduced from 44.3% to 29.2% (p = 0.023) in the bundles group, and the compliant subgroup had a more than twofold decrease in mortality (17.8% vs. 37.7%, p = 0.003). Serum lactate measured, blood cultures, and fluid resuscitation showed independent relationships with decreased mortality.

Conclusions

Total compliance was relatively low, but the implementation of severe sepsis bundles could clearly reduce mortality from severe CAP.