AS expected, the UK and Scottish governments have decided, after the first three weeks of restrictions to contain the spread of coronavirus, that they should remain in place. Strictly speaking, that is not an extension, but the default position; the legislation allows for the lockdown to continue for six months (when it must then be renewed by the parliaments). Interim reviews are to see whether the circumstances allow for relaxation, or indeed, require tightening of the measures.

As Westminster’s Health Secretary, Matt Hancock, pointed out yesterday – and as the First Minister readily agreed – Nicola Sturgeon’s comments on the likely steps to be taken in easing lockdown are hardly out of line with the UK government’ s approach to the coronavirus emergency.

WE should be wary of comparing the crisis of war with the crisis of coronavirus, but the 75th anniversary of VE Day is a reminder of what a national emergency can do to a leader. It can reveal their weaknesses and end their career, or it can highlight the qualities and skills that are needed in a time of trouble.

Rocker’s bum note

The efficacy of intravenous immunoglobulin and corticosteroid pulse combination therapy for refractory Kawasaki disease has been established. The Egami score can be used to predict which patients are likely to have refractory Kawasaki disease.

As a new strategy for primary treatment, intravenous immunoglobulin and corticosteroid pulse combination therapy is safe and effective for patients predicted to have refractory Kawasaki disease based on the Egami score. (Read the full article)

Infantile colic affects almost 10% of all infants and is characterized by crying and fussing in an otherwise healthy and well-fed infant. Prenatal exposure to tobacco smoking is a risk factor, but it is unclear whether nicotine causes the association.

Infants exposed to nicotine replacement therapy during pregnancy had elevated infantile colic risk of the same magnitude as infants exposed to tobacco smoking. Intrauterine exposure to nicotine may play a causal role in the pathogenesis of infantile colic. (Read the full article)

Pneumonia is still a significant problem in young children from developing countries where zinc deficiency is prevalent. Although zinc supplementation reduces the risk of childhood pneumonia, the effect of adjunct zinc on severe pneumonia is unclear with conflicting results.

The overall effect, if any, of zinc as adjuvant therapy for World Health Organization–defined severe pneumonia in young children is small. (Read the full article)

We know that many evidence-based treatments for acute asthma are underused, and adherence with treatment guidelines is poor; however, studies have focused on β₂ agonists and corticosteroids, but little is known about intravenous magnesium, which has substantial evidence of benefit.

Magnesium is used infrequently in Canadian pediatric emergency departments in hospitalized children with acute asthma, with variation across sites. More than half of this population does not receive frequent bronchodilators and timely corticosteroids. (Read the full article)

A dose-response relationship exists between light irradiance and decrease of total serum bilirubin concentration (TsB) at relatively low irradiances. It has been questioned whether by increasing irradiance a "saturation point" exists, above which no further decrease of TsB is seen.

We found a linear relation between light irradiance in the range of 20 to 55 μW/cm²/nm and decrease in TsB after 24 hours of therapy, with no evidence of a saturation point. (Read the full article)

There is evidence from both developed and developing countries that antiretroviral treatment significantly reduces mortality in HIV-infected children. However, in sub-Saharan Africa, numerous health system, financial, and human resource obstacles make delivering quality pediatric HIV care a challenge.

We describe the experience of the Baylor International Pediatrics AIDS Initiative in Malawi, Lesotho, and Swaziland. Despite challenges delivering pediatric treatment in these countries, mortality and clinical outcomes approaching those from developed countries are feasible. (Read the full article)

Pediatric osteoarticular infections can be treated with successful microbiologic and clinical outcomes with a transition from parenteral to oral therapy. The best way to determine the timing of this transition is neither well studied nor standardized.

A total of 193 (99.5%) of 194 pediatric patients with acute bacterial osteoarticular infections were successfully transitioned to oral therapy, determined by using a combination of clinical findings and C-reactive protein levels, representing the largest single-center data set analyzed. (Read the full article)

Expedited partner therapy (EPT) is an effective method of partner treatment of sexually transmitted infections but is not used frequently. There are limited data on provider knowledge, practices, and comfort with EPT use in adolescents.

California pediatric residents have knowledge gaps and discomfort providing EPT and presence of an adolescent medicine fellowship is associated with increased EPT knowledge, use, and comfort among residents. Our findings support the need to improve EPT education in pediatric residencies. (Read the full article)

Stressful events adversely affect the immune system, particularly the natural killer (NK) cells. Infants in the NICUs are exposed to stressful stimuli. The effect of massage therapy on the immune system of preterm infants has not been investigated.

This randomized placebo-controlled study found daily massage performed in stable preterm infants for a minimum of 5 days was associated with an increase in NK cell cytotoxicity despite lower absolute NK cell numbers compared with controls. (Read the full article)

Urban children suffer disproportionately from asthma, and suboptimal treatment with preventive medications is common. Although several programs have been developed to reduce morbidity for urban children with asthma, their economic feasibility and sustainability remain unknown.

Our study demonstrates that the school-based asthma therapy program could be an economically effective program for children aged 3 to 10 years attending preschool or elementary school in a city school district, at the cost of $10/symptom-free day. (Read the full article)

Diuretics are used in preterm infants to treat the symptoms of bronchopulmonary dysplasia (BPD), although there is little evidence of their effectiveness in improving long-term outcomes. Prescribing patterns and frequency of diuretic use in patients with BPD are unknown.

The use of diuretics in infants with BPD, including the specific medications used and length of treatment, varies widely by institution. Long-term diuretic administration to patients with BPD is commonly practiced despite minimal evidence regarding effectiveness and safety. (Read the full article)

Bronchiolitis, a leading cause of infant hospitalization, has few proven treatments. A few small studies have reported the beneficial effects of a mixture of 21% oxygen + 79% helium (Heliox). The 2010 Cochrane Review concluded that additional large randomized controlled trials were needed to determine the therapeutic role of Heliox in bronchiolitis.

The Bronchiolitis Randomized Controlled Trial Emergency-Assisted Therapy with Heliox—An Evaluation (BREATHE) trial is the largest multicenter randomized controlled trial to date to investigate the efficacy of Heliox in acute bronchiolitis. The delivery method for Heliox therapy was found to be crucial to its efficacy. (Read the full article)

Recorded music, parent voices, and sung lullabies have been shown to increase oxygen saturation, nonnutritive sucking, and weight gain in premature infants.

Parent-preferred melodies and entrained live rhythm and breath sounds can enhance quiet alert and sleep states, suck response, and oxygen saturation in premature infants and significantly reduce fear and anxiety perception in parents. (Read the full article)

Extremely preterm infants who receive antihypotensive therapy have worse outcomes than untreated infants. The reasons for this are not clear. High-quality randomized trials have not been performed to date because of logistical challenges, thereby necessitating alternative methods of investigation.

Antihypotensive therapy administration was not associated with improved in-hospital outcomes for any of the 15 definitions of low blood pressure investigated. Alternative methods of deciding who to treat are needed to maximize patient benefit and minimize harm. (Read the full article)

Cognitive behavioral therapy is an effective and safe treatment of chronic fatigue syndrome in children and adolescents. After 6 months, Internet-based cognitive behavioral therapy in the form of FITNET led to an 8 times higher chance of recovery compared with usual care.

The positive effects of FITNET were maintained at long-term follow-up (>2.5 years).Patients following usual-care treatment achieve similar recovery rates at long-term follow-up. (Read the full article)

Cognitive and behavioral problems after pediatric traumatic brain injury lead to poor functioning across multiple settings and can persist long-term after injury. Executive dysfunction is particularly common; however, there is a paucity of evidence-based interventions to guide treatment.

This study is among the largest randomized controlled trials performed in pediatric traumatic brain injury. It demonstrates the ability to use an online problem-solving-based intervention to improve caregiver ratings of executive dysfunction within 12 months after injury. (Read the full article)

Pediatric functional abdominal pain is common and costly. Cognitive behavior therapy (CBT) is a promising treatment for these complaints, but solid evidence for its effectiveness is lacking.

This randomized controlled trial shows that CBT reduces abdominal pain in 60% of children 1 year after treatment. Six sessions of CBT delivered by trained master’s students in psychology were equally effective as 6 visits to an experienced pediatrician. (Read the full article)

Recent guidelines for the management of childhood pneumonia recommend narrow-spectrum antimicrobial agents (eg, ampicillin) for most children; however, few studies have directly compared the effectiveness of narrow-spectrum agents to the broader spectrum third-generation cephalosporins commonly used among children hospitalized with pneumonia.

By using data from 43 children’s hospitals in the United States, we demonstrate equivalent outcomes and costs for children hospitalized with pneumonia and treated empirically with either narrow- (ampicillin/penicillin) or broad-spectrum (ceftriaxone/cefotaxime) antimicrobial therapy. (Read the full article)

Existing data do not demonstrate a need for combination therapy after antimicrobial susceptibility data indicate adequate in vitro activity with β-lactam monotherapy. However, the role of empirical combination therapy for the treatment of Gram-negative bacteremia in children remains unsettled.

We conducted a retrospective, propensity-score matched study demonstrating no improvement in 10-day mortality of children who have Gram-negative bacteremia receiving empirical β-lactam and aminoglycoside combination therapy compared with β-lactam monotherapy, unless the bacteremic episode was attributable to a multidrug-resistant organism. (Read the full article)

Home oxygen has been safely incorporated into emergency department management of bronchiolitis in certain populations. After discharge, a small proportion of patients (2.7%–6%) require subsequent admission. For patients managed successfully as outpatients, pediatricians report variable practice styles and comfort levels.

Our results define the clinical course and outpatient burden associated with discharge on home oxygen. By using an integrated health care system, we captured slightly higher rates (9.4%) of subsequent admission and found fever to be associated with this outcome. (Read the full article)

Hypothermia treatment of neonatal encephalopathy reduces death and disability from 66% to 50%; additional neuroprotective therapies are needed. We previously found in animal models that adding 50% xenon to the breathing gas during cooling doubled neuroprotection.

This clinical feasibility study used 50% xenon for 3 to 18 hours in 14 cooled infants with cardiovascular, respiratory, and amplitude-integrated EEG monitoring. This depressed seizures, with no blood pressure reduction. Xenon is ready for randomized clinical trials in newborns. (Read the full article)

Chorioamnionitis (CAM) is a major risk factor for early-onset neonatal sepsis. The Committee on the Fetus and Newborn recommends extending the duration of antimicrobial therapy in neonates exposed to CAM and intrapartum antibiotics if laboratory data are abnormal, even if culture results are sterile.

When managed by using a strategy similar to recent Committee on the Fetus and Newborn guidelines, a large number of term and late-preterm infants exposed to CAM who had sterile blood culture findings were treated with prolonged antibiotic therapy, subjected to additional invasive procedures, and had prolonged hospitalization. (Read the full article)

Animal studies document dose-dependent and duration-of-therapy-dependent fluoroquinolone cartilage toxicity in weight-bearing joints. Preliminary pediatric data collected after fluoroquinolone treatment and up to 1 year posttreatment in blinded and unblinded studies suggest the possibility of cartilage toxicity in children.

These are the first prospectively collected data on fluoroquinolone musculoskeletal safety collected posttherapy from randomized, comparative studies of respiratory tract infections and analyzed at 5 years. Long-term musculoskeletal adverse events occurred with equal frequency in both levofloxacin and comparator groups. (Read the full article)

In HIV-infected children, decisions to start antiretroviral therapy must weigh immunologic benefits against potential risks. Current guidelines recommend using CD4 percentage and age when deciding to start treatment. Population-level effects of these factors on immunologic recovery are unknown.

Starting antiretroviral therapy at higher CD4 percentages and younger ages maximizes potential for immunologic recovery. However, not all benefits are sustained, and viral failure may occur. Our results help clinicians better weigh immunologic benefits against viral failure risks. (Read the full article)

Phototherapy decreases bilirubin concentration in skin more rapidly than in blood. During and after phototherapy, transcutaneous bilirubin measurements are considered unreliable and therefore discouraged.

Transcutaneous bilirubin underestimates total serum bilirubin by 2.4 mg/dL (SD, 2.1 mg/dL) during the first 8 hours after phototherapy. This gives a safety margin of ~7 mg/dL below the treatment threshold to omit confirmatory blood sampling. (Read the full article)

Infants with Prader-Willi syndrome suffer from hypotonia, muscle weakness, and motor developmental delay and have increased fat mass combined with decreased muscle mass. Growth hormone improves body composition and motor development.

Ultrasound scans confirmed decreased muscle thickness in infants with Prader-Willi syndrome, which improved as result of growth hormone treatment. Muscle thickness was correlated to muscle strength and motor performance. Catch-up growth in muscle thickness was related to muscle use independent of growth hormone. (Read the full article)

Necrotizing enterocolitis is associated with high mortality and morbidity in premature infants. Anaerobic antimicrobial therapy has been associated with increased risk of intestinal strictures in a small randomized trial. Optimal antimicrobial therapy for necrotizing enterocolitis is unknown.

Anaerobic antimicrobial therapy was associated with increased risk of stricture formation. Infants with surgical necrotizing enterocolitis treated with anaerobic antimicrobial therapy had lower mortality. For infants with medical necrotizing enterocolitis, there was no added benefit associated with anaerobic antimicrobial therapy. (Read the full article)

Pediatric traumatic brain injury (TBI) contributes to impairments in functioning across multiple settings. Online family problem-solving therapy may be effective in reducing adolescent behavioral morbidity after TBI. However, less is known regarding maintenance of effects over time.

This large randomized clinical trial in adolescents with TBI is the only study to examine maintenance of treatment effects. Findings reveal that brief, online treatment may result in long-term improvements in child functioning, particularly among families of lower socioeconomic status. (Read the full article)

Smoking has been found to increase the risk of some specific congenital anomalies; however, results remain inconsistent. Nicotine replacement therapy (NRT) is increasingly being used as for smoking cessation in pregnancy although little is known about its association with congenital anomalies.

Being prescribed NRT while pregnant was not associated with major congenital anomalies (MCA), except a small increase in respiratory anomalies (3/1000 births). This must be considered in context of the rarity of MCAs and higher morbidities in the NRT group. (Read the full article)

Two prospective studies of children with septic arthritis have shown that the addition of dexamethasone to antibiotic therapy contributes to clinical and laboratory improvement. Nevertheless, the mainstay of treatment remains antibiotics alone.

This study, which was conducted outside a randomized controlled trial, demonstrates that children with septic arthritis treated early with a short course of adjuvant dexamethasone show earlier improvement in clinical and laboratory parameters than children treated with antibiotics alone. (Read the full article)

The future choices made by airlines matter a great deal for the oil market, say Liam Denning and Brooke Sutherland.

Objectives. The aim of this study was to assess the safety of early oral switch (EOS) prior to 14 days for low-risk Staphylococcus aureus bacteremia (LR-SAB), which is the primary treatment strategy employed at our institution. Usually recommended therapy is 14 days of intravenous (IV) antibiotics.

Methods. All patients with SAB at our hospital were identified between 1 January 2014 and 31 December 2018. Those meeting low-risk criteria (healthcare-associated, no evidence of deep infection or demonstrated involvement of prosthetic material, and no further positive blood cultures after 72-hours) were included in the study. The primary outcome was occurrence of a SAB-related complication within 90 days.

Results. There were 469 SAB episodes during the study period, 100 (21%) of whom met inclusion criteria. EOS was performed in 84 patients. In this group, line infection was the source in 79%, methicillin-susceptible S. aureus caused 95% of SABs and 74% of patients received IV flucloxacillin. The median duration of IV and oral antibiotics in the EOS group was 5 (IQR 4-6) and 10 days (IQR 9-14), respectively. Seventy-one percent of patients received flucloxacillin as their EOS agent. Overall, 86% of oral step-down therapy was with beta-lactams. One patient (1%) undergoing EOS had SAB relapse within 90 days. No deaths attributable to SAB occurred within 90 days.

Conclusions. In this low MRSA prevalence LR-SAB cohort, EOS was associated with a low incidence of SAB-related complications. This was achieved with oral beta-lactam therapy in most patients. Larger prospective studies are needed to confirm these findings.

Leishmania major is the causative agent of cutaneous leishmaniasis (CL). No human vaccine is available for CL and current drug regimens present several drawbacks such as emerging resistance, severe toxicity, medium effectiveness, and/or high cost. Thus, the need for better treatment options against CL is a priority. In the present study, we validate the enzyme methionine aminopeptidase-1 (MetAP1), a metalloprotease that catalyzes the removal of N-terminal methionine from peptides and proteins, as a chemotherapeutic target against CL infection. The in vitro antileishmanial activity of eight novel MetAP1 inhibitors (OJT001-OJT008) were investigated. Three compounds OJT006, OJT007, and OJT008 demonstrated potent anti-proliferative effect in macrophages infected with L. major amastigotes and promastigotes at submicromolar concentrations, with no cytotoxicity against host cells. Importantly, the leishmanicidal effect was diminished by almost 10-fold in transgenic L. major promastigotes overexpressing MetAP1_LM in comparison to wild-type promastigotes. Furthermore, the in vivo activity of OJT006, OJT007, and OJT008 were investigated in L. major-infected BALB/c mice. In comparison to the control group, OJT008 significantly decreased footpad parasite load by 86%, and exhibited no toxicity against in treated mice. We propose MetAP1 inhibitor OJT008 as a potential chemotherapeutic candidate against CL infection caused by L. major infection.

Since 2012, single low dose of primaquine (SLDPQ, 0.25mg/kg) has been recommended with artemisinin-based combination therapies, as first-line treatment of acute uncomplicated Plasmodium falciparum malaria, to interrupt its transmission, especially in low transmission settings of multidrug, including artemisinin, resistance. Policy makers in Cambodia have been reluctant to implement this recommendation due to primaquine safety concerns and lack of data on its efficacy.

In this randomized controlled trial, 109 Cambodians with acute uncomplicated P. falciparum malaria received dihydroartemisinin-piperaquine (DP) alone or combined with SLDPQ on the first treatment day. Transmission-blocking efficacy of SLDPQ was evaluated on Days 0, 1, 2, 3, 7, 14, 21, 28 and recrudescence by reverse transcriptase polymerase chain reaction (RT-PCR) (gametocyte prevalence) and membrane-feeding assays with Anopheles minimus mosquitoes (gametocyte infectivity). Without the influence of recrudescent infections, DP+SLDPQ reduced gametocyte carriage 3 fold compared to DP. Of 48 patients tested on Day 0, only three patients were infectious to mosquitoes (~6%). Post-treatment, three patients were infectious: on D14 (3.5%, 1/29), and on the first and seventh day of recrudescence (8.3%, 1/12 for each); this overall low infectivity precluded our ability to assess its transmission blocking efficacy.

Our study confirms effective gametocyte clearance of SLDPQ when combined with DP in multidrug resistant P. falciparum and the negative impact of recrudescent infections due to poor DP efficacy. Artesunate-mefloquine (ASMQ) has replaced DP and ASMQ-SLDPQ has been deployed to treat all P. falciparum symptomatic patients to further support the elimination of multidrug resistant P. falciparum in Cambodia.

Objectives: Antibiotic combination therapy is used for severe infections caused by multidrug-resistant (MDR) Gram-negative bacteria. Yet, data of which combinations are most effective is lacking. This study aimed to evaluate the in vitro efficacy of polymyxin B in combination with 13 other antibiotics against four clinical strains of MDR Pseudomonas aeruginosa.

Methods: We evaluated the interactions of polymyxin B in combination with amikacin, aztreonam, cefepime, chloramphenicol, ciprofloxacin, fosfomycin, meropenem, minocycline, rifampicin, temocillin, thiamphenicol or trimethoprim by automated time-lapse microscopy using predefined cut-off values indicating inhibition of growth (≤10⁶ CFU/mL) at 24 h. Promising combinations were subsequently evaluated in static time-kill experiments.

Results: All strains were intermediate or resistant to polymyxin B, anti-pseudomonal β-lactams, ciprofloxacin and amikacin. Genes encoding β-lactamases (e.g., bla_PAO and bla_OXA-50) and mutations associated with permeability and efflux were detected in all strains. In the time-lapse microscopy experiments, positive interactions were found with 39 of 52 antibiotic combination/bacterial strain setups. Enhanced activity was found against all four strains with polymyxin B used in combination with aztreonam, cefepime, fosfomycin, minocycline, thiamphenicol and trimethoprim. Time kill experiments showed additive or synergistic activity with 27 of the 39 tested polymyxin B combinations, most frequently with aztreonam, cefepime, and meropenem.

Conclusion: Positive interactions were frequently found with the tested combinations, also against strains that harboured several resistance mechanisms to the single drugs and with antibiotics that are normally not active against P. aeruginosa. Further study is needed to explore the clinical utility of these combinations.

Carbapenems are currently the preferred agents for the treatment of serious Acinetobacter infections. However, whether cefepime/cefpirome can be used to treat Acinetobacter bloodstream infection (BSI) if it is active against the causative pathogens is not clear. This study aimed to compare the efficacy of cefepime/cefpirome and carbapenem monotherapy in patients with Acinetobacter BSI. The population included 360 patients with monomicrobial Acinetobacter BSI receiving appropriate antimicrobial therapy admitted to four medical centres in Taiwan in 2012–2017. The predictors of 30-day mortality were determined by Cox regression analysis. The overall 30-day mortality rate in the appropriate antibiotic treatment group was 25.0% (90/360 patients), respectively. The crude 30-day mortality rates for cefepime/cefpirome and carbapenem therapy were 11.5% (7/61 patients) and 26.3% (21/80 patients), respectively. The patients receiving cefepime/cefpirome/carbapenem therapy were infected by Acinetobacter nosocomialis (51.8%), A. baumannii (18.4%) and A. pittii (12.1%). After adjusting for age, Sequential Organ Failure Assessment (SOFA) score, invasive procedures, and underlying diseases, cefepime/cefpirome therapy was not independently associated with a higher or lower 30-day mortality compared to the carbapenem therapy. SOFA score (hazard ratio [HR], 1.324; 95% confidence interval [CI], 1.137–1.543; P < 0.001) and neutropenia (HR, 7.060; 95% CI, 1.607–31.019; P = 0.010) were independent risk factors for 30-day mortality of patients receiving cefepime/cefpirome or carbapenem monotherapy. The incidence density of 30-day mortality for cefepime/cefpirome versus carbapenem therapy was 0.40% versus 1.04%. The therapeutic response of cefepime/cefpirome therapy was comparable to that of carbapenems among patients with Acinetobacter BSI receiving appropriate antimicrobial therapy.

Carbapenem-resistant Gram-negative pathogens are a critical public health threat and there is an urgent need for new treatments. Carbapenemases (β-lactamases able to inactivate carbapenems) have been identified in both serine β-lactamase (SBL) and metallo β-lactamase (MBL) families. The recent introduction of SBL carbapenemase-inhibitors has provided alternative therapeutic options. Unfortunately, there are no approved inhibitors of MBL-mediated carbapenem-resistance and treatment options for infections caused by MBL-producing Gram-negatives are limited. Here, we present ZN148, a zinc-chelating MBL-inhibitor capable of restoring the bactericidal effect of meropenem and in vitro clinical susceptibility to carbapenems in >98% of a large international collection of MBL-producing clinical Enterobacterales strains (n=234). Moreover, ZN148 was able to potentiate the effect of meropenem against NDM-1-producing Klebsiella pneumoniae in a murine neutropenic peritonitis model. ZN148 showed no inhibition of the human zinc-containing enzyme glyoxylase II at 500 μM and no acute toxicity was observed in an in vivo mouse model with cumulative dosages up to 128 mg/kg. Biochemical analysis showed a time-dependent inhibition of MBLs by ZN148 and removal of zinc ions from the active site. Addition of exogenous zinc after ZN148 exposure only restored MBL activity by ~30%, suggesting an irreversible mechanism of inhibition. Mass-spectrometry and molecular modelling indicated potential oxidation of the active site Cys221 residue. Overall, these results demonstrate the therapeutic potential of a ZN148-carbapenem combination against MBL-producing Gram-negative pathogens and that ZN148 is a highly promising MBL inhibitor, capable of operating in a functional space not presently filled by any clinically approved compound.

Ibrexafungerp (formerly SCY-078) is a semisynthetic triterpenoid and potent (1->3)-β-D-glucan synthase inhibitor. We investigated the in vitro activity, pharmacokinetics, and in vivo efficacy of ibrexafungerp (SCY) alone and in combination with anti-mould triazole isavuconazole (ISA) against invasive pulmonary aspergillosis (IPA). The combination of ibrexafungerp and isavuconazole in in vitro studies resulted in an additive and synergistic interactions against Aspergillus spp. Plasma concentration-time curves of ibrexafungerp were compatible with linear dose proportional profile. In vivo efficacy was studied in a well established persistently neutropenic NZW rabbit model of experimental IPA. Treatment groups included untreated rabbits (UC) and rabbits receiving ibrexafungerp at 2.5(SCY2.5) and 7.5(SCY7.5) mg/kg/day, isavuconazole at 40(ISA40) mg/kg/day, or combinations of SCY2.5+ISA40 and SCY7.5+ISA40. The combination of SCY+ISA produced in vitro synergistic interaction. There was significant in vivo reduction of residual fungal burden, lung weights, and pulmonary infarct scores in SCY2.5+ISA40, SCY7.5+ISA40, and ISA40-treatment groups vs that of SCY2.5-treated, SCY7.5-treated and UC (p<0.01). Rabbits treated with SCY2.5+ISA40 and SCY7.5+ISA40 had prolonged survival in comparison to that of SCY2.5-, SCY7.5-, ISA40-treated or UC (p<0.05). Serum GMI and (1->3)-β-D-glucan levels significantly declined in animals treated with the combination of SCY7.5+ISA40 in comparison to those treated with SCY7.5 or ISA40 (p<0.05). Ibrexafungerp and isavuconazole combination demonstrated prolonged survival, decreased pulmonary injury, reduced residual fungal burden, lower GMI and (1->3)-β-D-glucan levels in comparison to those of single therapy for treatment of IPA. These findings provide an experimental foundation for clinical evaluation of the combination of ibrexafungerp and an anti-mould triazole for treatment of IPA.

Background: Intensive care unit (ICU) patients may experience ceftriaxone underexposure but clinical outcomes data are lacking. The objective of this study was to determine the impact of ceftriaxone dosing on clinical outcomes amongst ICU patients without central nervous system (CNS) infection.

Methods: A retrospective study of ICU patients receiving intravenous, empiric ceftriaxone for non-CNS infections was conducted. Patients ≥18 years of age who received ≤2 grams of ceftriaxone daily for ≥72 hours were included and categorized as receiving ceftriaxone 1 gram or 2 grams daily. The primary, composite outcome was treatment failure: inpatient mortality and/or antibiotic escalation due to clinical worsening. Propensity score matching was performed based on the probability of receiving ceftriaxone 2 grams daily. Multivariable logistic regression determined the association between ceftriaxone dose and treatment failure in a propensity-matched cohort.

Results: A total of 212 patients were included in the propensity-matched cohort. The most common diagnoses (83.0%) were pneumonia and urinary tract infection. Treatment failure occurred in 17.0% and 5.7% of patients receiving 1 gram and 2 grams daily, respectively (p=0.0156). Overall inpatient mortality was 8.5%. Ceftriaxone 2 gram dosing was associated with a reduced likelihood of treatment failure (adjusted odds ratio=0.190; 95% confidence interval: 0.059 – 0.607). Other independent predictors of treatment failure included sequential organ failure assessment score (aOR 1.440, 95% CI 1.254 – 1.653) and creatinine clearance at 72 hours from ceftriaxone initiation (aOR 0.980, 95% CI (0.971 – 0.999).

Conclusions: Ceftriaxone 2 grams daily when used as appropriate antimicrobial coverage may be appropriate for ICU patients with lower mortality risk.

Mucormycosis is a life-threatening infection with high mortality that occurs predominantly in immunocompromised patients. Manogepix (MGX) is a novel antifungal that targets Gwt1, an early step in the conserved glycosylphosphotidyl inositol (GPI) post-translational modification pathway of surface proteins in eukaryotic cells. Inhibition of inositol acylation by MGX results in pleiotropic effects including inhibition of maturation of GPI-anchored proteins necessary for growth and virulence. MGX has been previously shown to have in vitro activity against some strains of Mucorales. Here we assessed the in vivo activity of the prodrug fosmanogepix, currently in clinical development for the treatment of invasive fungal infections, against two Rhizopus arrhizus strains with high (4.0 μg/ml) and low (0.25 μg/ml) minimum effective concentration (MEC) values. In both invasive pulmonary infection models, treatment of mice with 78 mg/kg or 104 mg/kg fosmanogepix, along with 1-aminobenzotriazole to enhance the serum half-live of MGX in mice, significantly increased median survival time and prolonged overall survival by day 21 post infection when compared to placebo. In addition, administration of fosmanogepix resulted in a 1-2 log reduction in both lung and kidney fungal burden. For the 104 mg/kg fosmanogepix dose, tissue clearance and survival were comparable to clinically relevant doses of isavuconazole (ISA), which is FDA approved for the treatment of mucormycosis. These results support continued development of fosmanogepix as a first in class treatment for invasive mucormycosis.

Telacebec (Q203) is a new anti-tubercular drug with extremely potent activity against Mycobacterium ulcerans. Here, we explored the treatment-shortening potential of Q203 alone or in combination with rifampin (RIF) in a mouse footpad infection model. The first study compared Q203 at 5 and 10 mg/kg doses alone and with rifampin. Q203 alone rendered most mouse footpads culture-negative in 2 weeks. Combining Q203 with rifampin resulted in relapse-free cure 24 weeks after completing 2 weeks of treatment, compared to a 25% relapse rate in mice receiving RIF+clarithromycin, the current standard of care, for 4 weeks.

The second study explored the dose-ranging activity of Q203 alone and with RIF, including the extended activity of Q203 after treatment discontinuation. The bactericidal activity of Q203 persisted for ≥ 4 weeks beyond the last dose. All mice receiving just 1 week of Q203 at 2-10 mg/kg were culture-negative 4 weeks after stopping treatment. Mice receiving 2 weeks of Q203 at 0.5, 2 and 10 mg/kg were culture-negative 4 weeks after treatment. RIF did not increase the efficacy of Q203. A pharmacokinetics sub-study revealed that Q203 doses of 2-10 mg/kg in mice produce plasma concentrations similar to those produced by 100-300 mg doses in humans, with no adverse effect of RIF on Q203 concentrations.

These results indicate the extraordinary potential of Q203 to reduce the duration of treatment necessary for cure to ≤ 1 week (or 5 doses of 2-10 mg/kg) in our mouse footpad infection model and warrant further evaluation of Q203 in clinical trials.

Objectives: Carbapenemase-producing Enterobacterales and specifically KPC-producing Klebsiella pneumoniae (KPC-Kp) are rapidly spreading worldwide. The prognosis of ventilator-associated pneumonia (VAP) caused by KPC-producing Klebsiella pneumoniae (KPC-Kp) is not well known. Our study tries to assess whether ventilator-associated pneumonia caused by a KPC-Kp strain is associated with higher all-cause mortality than if caused by carbapenem-susceptible isolates.

Study design and methods: This is a retrospective cohort study of patients with VAP due to K. pneumoniae from a 35-bed polyvalent Intensive Care Unit in a university hospital (> 40,000 annual admissions) between January 2012 and December 2016. Adjusted multivariate analysis was used to study the association of KPC-Kp with 30-day all-cause mortality (Cox regression).

Results. We analyze 69 cases of K. pneumoniae VAP of which 39 were produced by a KPC-Kp strain with high-level resistance to meropenem (MIC > 16 mg/mL). All-cause mortality at 30 days was 41% in the KPC-Kp group (16/39) and 33.3% in the carbapenem-susceptible cases (10/30). KPC-Kp etiology was not associated with higher mortality when controlled for confounders (adjusted hazard ratio [lsqb]HR[rsqb] 1.25; 95% CI: 0.46–3.41). Adequate targeted therapy (HR 0.03; 95% CI: <0.01–0.23) was associated with all-cause mortality.

Conclussion. Assuming the limitations due to the available sample size, the prognosis of VAP caused by KPC-Kp is similar to VAPs caused by carbapenem-susceptible K. pneumoniae when appropriate treatment is used.

Contezolid (MRX-I), a new oxazolidinone, is an antibiotic in development for treating complicated skin and soft tissue infections (cSSTI) caused by resistant Gram-positive bacteria. This was a thorough QT study conducted in 52 healthy subjects who were administered oral contezolid at a therapeutic (800 mg) dose, a supratherapeutic (1600 mg) dose, placebo, and oral moxifloxacin 400 mg in 4 separate treatment periods. The pharmacokinetic profile of contezolid was also evaluated. Time-point analysis indicated that the upper bounds of the two-sided 90% confidence interval (CI) for placebo-corrected change-from-baseline QTc (QTc) were <10 ms for the contezolid therapeutic dose at each time point. The upper bound of the 90% CI for QTc were slightly more than 10 ms with the contezolid supratherapeutic dose at 3 and 4 hours postdose, and the prolongation effect on the QT/QTc interval was less than that of the positive control, moxifloxacin 400 mg. At 3 and 4 h after the moxifloxacin dose, the moxifloxacin group met the assay sensitivity criteria outlined in ICH Guidance E14 with having a lower confidence bound ≥5 ms. The results of a linear exposure-response model which were similar to that of a time point analysis demonstrated a slightly positive relationship between contezolid plasma levels and QTcF interval with a slope of 0.227 ms per mg/L (90% CI: 0.188 to 0.266). In summary, contezolid did not prolong the QT interval at a therapeutic dose and may have a slight effect on QT interval prolongation at a supratherapeutic dose.

Mycobacterium abscessus lung infections remain difficult to treat. Recent studies have recognized the power of new combinations of antibiotics such as bedaquiline and imipenem although in vitro data have questioned this combination. We report that the efficacy of the bedaquiline plus imipenem treatment relies essentially on the activity of bedaquiline in a C3HeB/FeJ mice model of infection with a rough variant of M. abscessus. The addition of imipenem contributed at clearing the infection in the spleen.

The human diseases caused by the fungal pathogens Cryptococcus neoformans and C. gattii are associated with high indices of mortality, and toxic and/or cost-prohibitive therapeutic protocols. The need for affordable antifungals to combat cryptococcal disease is unquestionable. Previous studies suggested benzimidazoles as promising anti-cryptococcal agents combining low cost and high antifungal efficacy, but their therapeutic potential has not been demonstrated so far. In this study, we investigated the antifungal potential of fenbendazole, the most effective anti-cryptococcal benzimidazole. Fenbendazole was inhibitory against 17 different isolates of C. neoformans and C. gattii at a low concentration. The mechanism of anti-cryptococcal activity of fenbendazole involved microtubule disorganization, as previously described for human parasites. In combination with fenbendazole, the concentrations of the standard antifungal amphotericin B required to control cryptococcal growth were lower than those required when this antifungal was used alone. Fenbendazole was not toxic to mammalian cells. During macrophage infection, the anti-cryptococcal effects of fenbendazole included inhibition of intracellular proliferation rates and reduced phagocytic escape through vomocytosis. Fenbendazole deeply affected the cryptococcal capsule. In a mice model of cryptococcosis, the efficacy of fenbendazole to control animal mortality was similar to that observed for amphotericin B. These results indicate that fenbendazole is a promising candidate for the future development of an efficient and affordable therapeutic tool to combat cryptococcosis.

Carbapenem pharmacokinetic profiles are significantly changed in critically ill patients because of the drastic variability of the patients' physiological parameters. Published population PK studies have mainly focused on specific diseases and the majority of these studies had small sample sizes. The aim of this study was to develop a population PK model of imipenem in critically ill patients that estimated the influence of various clinical and biological covariates and the use of Extracorporeal Membrane Oxygenation (ECMO) and Continuous Renal Replacement Therapy (CRRT). A two-compartment population PK model with Creatinine clearance (CrCL), body weight (WT), and ECMO as fixed effects was developed using the non-linear mixed effect model (NONMEM). A Monte Carlo simulation was performed to evaluate various dosing schemes and different levels of covariates based on the pharmacokinetic/pharmacodynamic index (f%T>MIC) for the range of clinically relevant minimum inhibitory concentrations(MICs). The results showed that there may be insufficient drug use in the clinical routine drug dose regimen, and 750mg Q6h could achieve a higher treatment success rate. The blood concentrations of imipenem in ECMO patients were lower than that of non-ECMO patients, therefore dosage may need to be increased. The dosage may need adjustment for patients with CrCL ≤ 70ml/min, but dose should be lowered carefully to avoid the insufficient drug exposure. Dose adjustment is not necessary for patients within the WT ranging from 50-80 kg. Due to the large variation in PK profile of imipenem in critically ill patients, TDM should be carried out to optimize drug regimens.