Background. Recurrent therapeutic failures reported for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infective endocarditis (IE) with vancomycin may be due to poor bactericidal ...activity. Alternative antibacterial approaches using bacteriophages may overcome this limitation. Objectives. An experimental rat model of MRSA IE (EE) was used to examine the efficacy of vancomycin combined with a 1:1 bacteriophage (phage) cocktail composed of Herelleviridae vB_SauH_2002 and Routreeviridae 66. Methods. Six hours after inoculation with ca. 5 log10 colony forming units (CFU) of MRSA strain AW7, animals were treated with either: (i) saline, (ii) an equimolar two-phage cocktail (bolus of 1 mL followed by a 0.3 mL/h continuous infusion of 10 log10 plaque forming units (PFU)/mL phage suspension), (iii) vancomycin (at a dose mimicking the kinetics in humans of 0.5 g b.i.d.), or (iv) a combination of both. Bacterial loads in vegetations, and phage loads in vegetations, liver, kidney, spleen, and blood, were measured outcomes. Results. Phage cocktail alone was unable to control the growth of strain AW7 in cardiac vegetations. However, when combined with subtherapeutic doses of vancomycin, a statistically significant decrease of ∆4.05 ± 0.94 log10 CFU/g at 24 h compared to placebo was detected (p < 0.001). The administration of vancomycin was found to significantly impact on the local concentrations of phages in the vegetations and in the organs examined. Conclusions. Lytic bacteriophages as an adjunct treatment to the standard of care antibiotics could potentially improve the management of MRSA IE. Further studies are needed to investigate the impact of antibiotics on phage replication in vivo.
Background The potential of phage therapy for the treatment of endovascular
infections remains to be evaluated. Methods and Results The efficacy of a phage cocktail combining
phage vB_SauH_2002 and
...phage 66 was evaluated against a methicillin-sensitive
strain in vitro and in vivo in a rodent model of experimental endocarditis. Six hours after bacterial challenge, animals were treated with (1) the phage cocktail. (2) subtherapeutic flucloxacillin dosage, (3) combination of the phage cocktail and flucloxacillin, or (4) saline. Bacterial loads in cardiac vegetations at 30 hours were the primary outcome. Secondary outcomes were phage loads at 30 hours in cardiac vegetations, blood, spleen, liver, and kidneys. We evaluated phage resistance 30 hours post infection in vegetations of rats under combination treatment. In vitro, phages synergized against
planktonic cells and the cocktail synergized with flucloxacillin to eradicated biofilms. In infected animals, the phage cocktail achieved bacteriostatic effect. The addition of low-dose flucloxacillin elevated bacterial suppression (∆ of -5.25 log
colony forming unit/g CFU/g versus treatment onset,
<0.0001) and synergism was confirmed (∆ of -2.15 log
CFU/g versus low-dose flucloxacillin alone,
<0.01). Importantly, 9/12 rats given the combination treatment had sterile vegetations at 30 hours. In vivo phage replication was partially suppressed by the antibiotic and selection of resistance to the
component of the phage cocktail occurred. Plasma-mediated inhibition of phage killing activity was observed in vitro. Conclusions Combining phages with a low-dose standard of care antibiotic represents a promising strategy for the treatment of
infective endocarditis.
Acinetobacter pittii is a species that belong to the Acinetobacter calcoaceticus-baumannii complex, increasingly recognized as major nosocomial bacterial pathogens, often associated with multiple ...drug-resistances. The capsule surrounding the bacteria represents a main virulence factor, helping cells avoid phage predation and host immunity. Accordingly, a better understanding of the phage infection mechanisms is required to efficiently develop phage therapy against Acinetobacter of different capsular types. Here, we report the isolation of the novel A. pittii-infecting Fri1-like phage vB_Api_3043-K38 (3043-K38) of the Podoviridae morphotype, from sewage samples. Its 41,580 bp linear double-stranded DNA genome harbours 53 open reading frames and 302 bp of terminal repeats. We show that all studied Acinetobacter Fri1-like viruses have highly similar genomes, which differentiate only at the genes coding for tailspike, likely to adapt to different host receptors. The isolated phage 3043-K38 specifically recognizes an untapped Acinetobacter K38 capsule type via a novel tailspike with K38 depolymerase activity. The recombinant K38 depolymerase region of the tailspike (center-end region) forms a thermostable trimer, and quickly degrades capsules. When the K38 depolymerase is applied to the cells, it makes them resistant to phage predation. Interestingly, while K38 depolymerase treatments do not synergize with antibiotics, it makes bacterial cells highly susceptible to the host serum complement. In summary, we characterized a novel phage-encoded K38 depolymerase, which not only advances our understanding of phage-host interactions, but could also be further explored as a new antibacterial agent against drug-resistant Acinetobacter.
IntroductionDuring pandemics, such as the SARS-CoV-2, filtering facepiece respirators plays an essential role in protecting healthcare personnel. The recycling of respirators is possible in case of ...critical shortage, but it raises the question of the effectiveness of decontamination as well as the performance of the reused respirators.MethodDisposable respirators were subjected to ultraviolet germicidal irradiation (UVGI) treatment at single or successive doses of 60 mJ/cm2 after a short drying cycle (30 min, 70°C). The germicidal efficacy of this treatment was tested by spiking respirators with two staphylococcal bacteriophages (vB_HSa_2002 and P66 phages). The respirator performance was investigated by the following parameters: particle penetration (NaCl aerosol, 10–300 nm), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry and mechanical tensile tests.ResultsNo viable phage particles were recovered from any of the respirators after decontamination (log reduction in virus titre >3), and no reduction in chemical or physical properties (SEM, particle penetrations <5%–6%) were observed. Increasing the UVGI dose 10-fold led to chemical alterations of the respirator filtration media (FTIR) but did not affect the physical properties (particle penetration), which was unaltered even at 3000 mJ/cm2 (50 cycles). When respirators had been used by healthcare workers and undergone decontamination, they had particle penetration significantly greater than never donned respirators.ConclusionThis decontamination procedure is an attractive method for respirators in case of shortages during a SARS pandemic. A successful implementation requires a careful design and particle penetration performance control tests over the successive reuse cycles.
Background. Recurrent therapeutic failures reported for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infective endocarditis (IE) with vancomycin may be due to poor bactericidal ...activity. Alternative antibacterial approaches using bacteriophages may overcome this limitation. Objectives. An experimental rat model of MRSA IE (EE) was used to examine the efficacy of vancomycin combined with a 1:1 bacteriophage (phage) cocktail composed of Herelleviridae vB_SauH_2002 and Routreeviridae 66. Methods. Six hours after inoculation with ca. 5 logsub.10 colony forming units (CFU) of MRSA strain AW7, animals were treated with either: (i) saline, (ii) an equimolar two-phage cocktail (bolus of 1 mL followed by a 0.3 mL/h continuous infusion of 10 logsub.10 plaque forming units (PFU)/mL phage suspension), (iii) vancomycin (at a dose mimicking the kinetics in humans of 0.5 g b.i.d.), or (iv) a combination of both. Bacterial loads in vegetations, and phage loads in vegetations, liver, kidney, spleen, and blood, were measured outcomes. Results. Phage cocktail alone was unable to control the growth of strain AW7 in cardiac vegetations. However, when combined with subtherapeutic doses of vancomycin, a statistically significant decrease of ∆4.05 ± 0.94 logsub.10 CFU/g at 24 h compared to placebo was detected (p < 0.001). The administration of vancomycin was found to significantly impact on the local concentrations of phages in the vegetations and in the organs examined. Conclusions. Lytic bacteriophages as an adjunct treatment to the standard of care antibiotics could potentially improve the management of MRSA IE. Further studies are needed to investigate the impact of antibiotics on phage replication in vivo.
Infections caused by multidrug-resistant bacteria are a major clinical challenge. Phage therapy is a promising alternative antibacterial strategy.
To evaluate the efficacy of intravenous phage ...therapy for the treatment of ventilator-associated pneumonia due to methicillin-resistant
in rats.
In a randomized, blinded, controlled experimental study, we compared intravenous teicoplanin (3 mg/kg,
= 12), a cocktail of four phages (2-3 × 10
plaque-forming units/ml of 2003, 2002, 3A, and K;
= 12), and a combination of both (
= 11) given 2, 12, and 24 hours after induction of pneumonia, and then once daily for 4 days. The primary outcome was survival at Day 4. Secondary outcomes were bacterial and phage densities in lungs and spleen, histopathological scoring of infection within the lungs, and inflammatory biomarkers in blood.
Treatment with either phages or teicoplanin increased survival from 0% to 58% and 50%, respectively (
< 0.005). The combination of phages and antibiotics did not further improve outcomes (45% survival). Animal survival correlated with reduced bacterial burdens in the lung (1.2 × 10
cfu/g of tissue for survivors vs. 1.2 × 10
cfu/g for nonsurviving animals;
< 0.0001), as well as improved histopathological outcomes. Phage multiplication within the lung occurred during treatment. IL-1β increased in all treatment groups over the course of therapy.
Phage therapy was as effective as teicoplanin in improving survival and decreasing bacterial load within the lungs of rats infected with methicillin-resistant
. Combining antibiotics with phage therapy did not further improve outcomes.
•Bacteraemia can be caused by Acinetobacter baumannii.•Extensively drug-resistant Acinetobacter baumannii (XDRAB) strains have emerged.•A lack of new antimicrobials has led to a renewed interest in ...phage therapy.•Phage therapy rescued mice with bacteraemia induced by an XDRAB strain.
Bacteraemia can be caused by Acinetobacter baumannii (A. baumannii), with clinical manifestations ranging from transient bacteraemia to septic shock. Extensively drug-resistant A. baumannii (XDRAB) strains producing the New Delhi metallo-ß-lactamase, which confers resistance to all ß-lactams including carbapenems, have emerged. Infected patients suffer increased mortality, morbidity and length of hospitalisation. The lack of new antimicrobials has led to a renewed interest in phage therapy, the so-called forgotten cure. Accordingly, we tested new lytic bacteriophages in a Galleria mellonella and a mouse model of XDRAB-induced bacteraemia.
Galleria mellonella were challenged with 5.105 CFU of the XDRAB strain FER. Phages vB_AbaM_3054 and vB_AbaM_3090 were administrated alone or in combination 30min after bacterial challenge. Saline and imipenem were injected as controls. Mice were intraperitoneally (i.p.) challenged with 6.107 CFU of A. baumannii FER. vB_AbaM_3054 and vB_AbaM_3090 were administrated i.p. alone or in combination 2h after bacterial challenge. Saline and imipenem were injected as controls. Larvae and mice survival were followed for 7 days and compared with Log-Rank (Mantel-Cox) and Gehan-Breslow-Wilcoxon tests.
Phage-based treatments showed high efficacy in larvae (ca. 100% survival at 80h) and mice (ca. 100% survival at day 7) compared with the untreated controls (0% survival at 48h and 24h in larvae and mice, respectively).
The present data reporting efficacy of phage therapy in a mouse model of bacteraemia support the development of phage-based drugs to manage infection due to multi-drug resistant A. baumannii and particularly XDRAB.
A retrospective cohort study of prospectively collected data.
As an initial effort to address readmissions after lumbar discectomy, reasons for hospital readmission are identified and discussed.
...Lumbar discectomy is a commonly performed procedure. The Affordable Care Act codifies penalties for hospital readmissions. New quality-based reimbursements tied to readmissions call for a better understanding of the causes of readmission after procedures such as lumbar discectomy.
Lumbar discectomies performed in 2012 to 2014 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Patient demographics, surgical variables, and reasons for readmissions within 30 days were recorded. Pearson chi square was used to compare rates of demographics and surgical variables between readmitted and nonreadmitted patients. Multivariate regression was used to identify risk factors for readmission.
Of 20,376 lumbar discectomies, 533 patients (2.62%) were readmitted within 30 days of surgery. The most common reasons for readmission were surgical site infections (n = 130, 0.64% of all discectomies, 24.4% of all readmissions), followed by pain issues (n = 89, 0.44%, 16.7%), and thromboembolic events (43, 0.21%, 8.1%). Overall time to readmission was 13.0 ± 8.0 days (mean ± standard deviation). Factors most associated with readmission after lumbar discectomy were higher American Society of Anesthesiologists class (relative risk = 1.49, P < 0.001) and prolonged operative time (relative risk = 1.41, P = 0.002).
Surgical site infection, postoperative pain, and thromboembolic events were the most common reasons for readmission after lumbar discectomy. These findings identify potential areas for quality improvement initiatives.
3.
Background & Aims The incidence of esophageal and junctional adenocarcinoma has increased 6-fold in the past 30 years and 5-year survival remains approximately 20%. Current staging is limited in its ...ability to predict survival which has ramifications for treatment choices. The aim of this study was to generate and validate a molecular prognostic signature for esophageal adenocarcinoma. Methods Gene expression profiling was performed and the resulting 42,000 gene signatures correlated with clinical and pathologic features for 75 snap-frozen esophageal and junctional resection specimens. External validation of selected targets was performed on 371 independent cases using immunohistochemistry to maximize clinical applicability. Results A total of 119 genes were associated significantly with survival and 270 genes with the number of involved lymph nodes. Filtering of these lists resulted in a shortlist of 10 genes taken forward to validation. Four genes proved to be prognostic at the protein level (deoxycytidine kinase DCK, 3′-phosphoadenosine 5′-phosphosulfate synthase 2 PAPSS2, sirtuin 2 SIRT2, and tripartite motif-containing 44 TRIM44) and were combined to create a molecular prognostic signature. This 4-gene signature was highly predictive of survival in the independent external validation cohort (0/4 genes dysregulated 5-year survival, 58%; 95% confidence interval CI, 36%–80%; 1–2/4 genes dysregulated 5-year survival, 26%; 95% CI, 20%–32%; and 3–4/4 genes dysregulated 5-year survival, 14%; 95% CI, 4%–24% ( P = .001). Furthermore, this 4-gene signature was independently prognostic in a multivariable model together with the existing clinical TNM staging system ( P = .013). Conclusions This study has generated a clinically applicable prognostic gene signature that independently predicts survival in an external validation cohort and may inform management decisions.
Prospective cohort study.
To determine the effects of insurance type (Medicaid vs. a specific private insurance) on patient access to spine surgeons for lumbar disc herniation as measured by (A) ...acceptance of insurance, (B) need for a referral, and (C) wait time for appointment.
Limited studies have been conducted to examine the issue of patient access to spine surgeons based on different insurance types (Medicaid vs. a specific private insurance), especially in relation to the Medicaid expansion that resulted from the Affordable Care Act.
Appointment success rates, the need for a referral, and waiting periods were compared between Medicaid and a specific private insurance for patients needing an evaluation for a herniated lumbar disc. The waiting period was studied in the context of comparing states that have expanded Medicaid eligibility to ones that have not, and the surgical training of the spine surgeon (orthopaedic surgeons vs. neurosurgeons).
Appointment success rate for patients seeking access to lumbar spine care was significantly higher for patients with BlueCross insurance (95.0%) versus patients with Medicaid insurance (0.8%) (P <0.001). The need for referrals was significantly higher for patients with Medicaid insurance (93.3%) versus patients with BlueCross insurance (4.2%) (P <0.001). Among BlueCross patients, wait times were longer in Medicaid-expanded states. However, the same trend was not seen among patients with Medicaid insurance.
Patients with Medicaid were less successful at scheduling an appointment and faced more barriers to care, such as the need for a referral, compared with the private insurance studied. In the states with expanded Medicaid, wait times for appointments were longer for BlueCross patients, but were not longer for patients with Medicaid insurance. Overall, this study suggests that increased coverage resulting from Medicaid expansion does not necessarily equate to increased access to care.
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