Burn or trauma scoring: experience of the burn unit of the Queen Astrid Military Hospital during the terror attacks on 22 March 2016.

PURPOSE: On 22 March 2016, the burn unit (BU) of Queen Astrid Military Hospital assessed a surge in severely injured victims from terror attacks at the national airport and Maalbeek subway station according to the damage control resuscitation (DCR) and damage control surgery (DCS) principles. This study delves into its approach to identify a suitable triage scoring system and to determine if a BU can serve as buffer capacity for mass casualty incidents (MCIs). METHODS: The study reviewed retrospectively the origin of explosion, demographic data, sustained injuries, performed surgery, and length of stay of all admitted patients. Trauma scores (Injury Severity Score (ISS) and New Injury Severity Score (NISS)) and triage scores (Revised Trauma Score (RTS), New Trauma Score (NTS), and Trauma Score Injury Severity Score (TRISS)), were compared to burn mortality scores (Osler updated Baux Score and Tobiasen's Abbreviated Burn Severity Index (ABSI)). RESULTS: Of the 23 casualties admitted to the BU, the scores calculated on average 3.5 indications for a level 1 trauma center (ISS 4, NISS 6, RTS 0, T-NTS 4). Nevertheless, no deaths occurred during admission or the 1-year follow-up. CONCLUSION: MCIs create chaos and a high demand for care. Avoiding bottlenecks and adhering to the DCR/DCS principles are necessary to deliver the best care to the largest number of people. This study indicates that a BU can serve as buffer capacity for MCIs. Nevertheless, its integration into the medical resilience plan depends on accurate scoring, comprehensive care availability, and understanding of the DCR/DCS concept. NTS for triage seems the best fit for scoring polytrauma referrals to a BU during MCIs.

Bacteriophages for the treatment of pseudomonas-infected vascular prosthesis.

We present a case report detailing therapeutic application of two lytic antipseudomonal bacteriophages to treat a chronic relapsing Pseudomonas aeruginosa infection of a prosthetic aortic graft. As there are currently no Danish laboratories offering phages for clinical therapy, and this case, to our knowledge represents the first applied phage therapy in Denmark, the practical and regulatory aspects of offering this treatment option in Denmark is briefly reviewed along with the clinical case.

Improving phage therapy by evasion of phage resistance mechanisms.

Antibiotic failure is one of the most worrisome threats to global health. Among the new therapeutic efforts that are being explored, the use of bacteriophages (viruses that kill bacteria), also known as 'phages', is being extensively studied as a strategy to target bacterial pathogens. However, one of the main drawbacks of phage therapy is the plethora of defence mechanisms that bacteria use to defend themselves against phages. This review aims to summarize the therapeutic approaches that are being evaluated to overcome the bacterial defence systems, including the most innovative therapeutic approaches applied: circumvention of phage receptor mutations; modification of prophages; targeting of CRISPR-Cas systems and the biofilm matrix; engineering of safer and more efficacious phages; and inhibition of the anti-persister strategies used by bacteria.

Exploiting phage-antibiotic synergies to disrupt Pseudomonas aeruginosa PAO1 biofilms in the context of orthopedic infections.

IMPORTANCE: Biofilm-related infections are among the most difficult-to-treat infections in all fields of medicine due to their antibiotic tolerance and persistent character. In the field of orthopedics, these biofilms often lead to therapeutic failure of medical implantable devices and urgently need novel treatment strategies. This forthcoming article aims to explore the dynamic interplay between newly isolated bacteriophages and routinely used antibiotics and clearly indicates synergetic patterns when used as a dual treatment modality. Biofilms were drastically more reduced when both active agents were combined, thereby providing additional evidence that phage-antibiotic combinations lead to synergism and could potentially improve clinical outcome for affected patients.

Bacteriophage Production in Compliance with Regulatory Requirements.

In this chapter, we discuss production requirements for therapeutic bacteriophage preparations. We review the current regulatory expectancies and focus on pragmatic production processes, implementing relevant controls to ensure the quality, safety, and efficacy of the final products. The information disclosed in this chapter can also serve as a basis for discussions with competent authorities regarding the implementation of expedited bacteriophage product development and licensing pathways, taking into account some peculiarities of bacteriophages (as compared to conventional medicines), such as their specificity for, and co-evolution with, their bacterial hosts. To maximize the potential of bacteriophages as natural controllers of bacterial populations, the implemented regulatory frameworks and manufacturing processes should not only cater to defined bacteriophage products. But, they should also facilitate personalized approaches in which bacteriophages are selected ad hoc and even trained to target the patient's infecting bacterial strain(s), whether or not in combination with other antimicrobials such as antibiotics.

Guidelines to Compose an Ideal Bacteriophage Cocktail.

Properly designed bacteriophage therapeutics are the cornerstone for a successful outcome of bacteriophage therapy. Here we present an overview of the different strategies and steps that can be taken to develop a bacteriophage cocktail that complies with relevant quality and safety requirements. It is based on empirical bacteriophage therapy knowledge from over a century of experience, more recently performed studies, and emerging technologies. We emphasize the selection of adequate bacteriophages and describe a modified Appelmans' method to improve the overall performance of therapeutic bacteriophages individually and collectively in the cocktail. We present two versions of the method, which differ from each other by the employed techniques to evaluate phage activity and synergy: photometric assessment of bacterial growth versus measurement of bacterial respiration via the Omnilog® system.

Magistral Phage Preparations: Is This the Model for Everyone?

Phage therapy is increasingly put forward as a promising additional tool to help curb the global antimicrobial resistance crisis. However, industrially manufactured phage medicinal products are currently not available on the European Union and United States markets. In addition, it is expected that the business purpose-driven phage products that are supposed to be marketed in the future would mainly target commercially viable bacterial species and clinical indications, using fixed phage cocktails. hospitals or phage therapy centers aiming to help all patients with difficult-to-treat infections urgently need adequate phage preparations. We believe that national solutions based on the magistral preparation of personalized (preadapted) phage products by hospital and academic facilities could bring an immediate solution and could complement future industrially manufactured products. Moreover, these unlicensed phage preparations are presumed to be more efficient and to elicit less bacterial phage resistance issues than fixed phage cocktails, claims that need to be scientifically substantiated as soon as possible. Just like Belgium, other (European) countries could develop a magistral phage preparation framework that would exist next to the conventional medicinal product development and licensing pathways. However, it is important that the current producers of personalized phage products are provided with pragmatic quality and safety assurance requirements, which are preferably standardized (at least at the European level), and are tiered based on benefit-risk assessments at the individual patient level. Pro bono phage therapy providers should be supported and not stopped by the imposition of industry standards such as Good Manufacturing Practice requirements. Keywords: antimicrobial resistance; antibiotic resistance; bacterial infection; bacteriophage therapy; magistral preparation.

Phages and phage-borne enzymes as new antibacterial agents.

BACKGROUND: Persistent and resistant infections caused by bacteria are increasing in numbers and pose a treatment challenge to the medical community and public health. However, solutions with new agents that will enable effective treatment are lacking or delayed by complex development and authorizations. Bacteriophages are known as a possible solution for invasive infections for decades but were seldom used in the Western world. OBJECTIVES: To provide an overview of the current status and emerging use of bacteriophage therapy and phage-based products, as well as touch on the socioeconomic and regulatory issues surrounding their development. SOURCES: Peer-reviewed articles and authors' first-hand experience. CONTENT: Although phage therapy is making a comeback since its early discovery, there are many hurdles to its current use. The lack of appropriate standardized bacterial susceptibility testing; lack of a simple business model and authorization for the need of many phages to treat a single species infection; and the lack of knowledge on predictable outcome measures are just a few examples. In this review, we explore the possible routes for phage use, either based on local specialty centres or by industry; the current status of phage therapy, which is mainly based on single-centre or single-bacterial cohorts, and emerging clinical trials; local country-level frameworks for phage utilization even without full authorization; and the use of phage-derived products as alternatives to antibiotics. We also explore what may be the current indications based on the possible availability of phages. IMPLICATIONS: Although phages are emerging as a potential treatment for non-resolving and life-threatening infections, the models for their use and production still need to be defined by the medical community, regulatory bodies, and industry. Bacteriophages may have a great potential for infection treatment but many aspects still need to be defined before their routine use in the clinic.

Stability of magistral phage preparations before therapeutic application in patients with chronic rhinosinusitis, sepsis, pulmonary, and musculoskeletal infections.

IMPORTANCE: As antimicrobial resistance becomes more prevalent, the application of (bacterio)phage therapy as an alternative treatment for difficult-to-treat infections is (re)gaining popularity. Over the past decade, numerous promising case reports and series have been published demonstrating the therapeutic potential of phage therapy. However, important questions remain regarding the optimal treatment protocol and, unlike for medicinal products, there are currently no predefined quality standards for the stability of phage preparations. Phage titers can be influenced by several factors which could lead to reduced titers after preparation and storage and, ultimately, subtherapeutic applications. Determining the stability of different phages in different recipients according to the route of administration is therefore one of the first important steps in establishing a standardized protocol for phage therapy.

Preanalytical variables influencing the interpretation and reporting of biological tests on blood samples of living and deceased donors for human body materials.

With the present paper, the Working Group on Cells, Tissues and Organs and other experts of the Superior Health Council of Belgium aimed to provide stakeholders in material of human origin with advice on critical aspects of serological and nucleic acid test (NAT) testing, to improve virological safety of cell- and tissue and organ donation. The current paper focusses on a number of preanalytical variables which can be critical for any medical biology examination: (1) sampling related variables (type of samples, collection of the samples, volume of the sample, choice of specific tubes, identification of tubes), (2) variables related to transport, storage and processing of blood samples (transport, centrifugation and haemolysis, storage before and after centrifugation, use of serum versus plasma), (3) variables related to dilution (haemodilution, pooling of samples), and (4) test dependent variables (available tests and validation). Depending on the type of donor (deceased donor (heart-beating or non-heart beating) versus living donor (allogeneic, related, autologous), and the type of donated human material (cells, tissue or organs) additional factors can play a role: pre- and post-mortem sampling, conditions of sampling (e.g. morgue), haemodilution, possibility of retesting.

Phage Therapy for Diabetic Foot Infection: A Case Series.

PURPOSE: Infected diabetic foot ulcers can be difficult to treat and, despite appropriate antibiotic therapy, some diabetic foot infections (DFIs) require amputation. Bacteriophages (phages) are viruses that infect and kill bacteria. Phage therapy has been repeatedly used to successfully treat DFIs and other chronic wounds. METHODS: This article reports the provision of topical adjunctive anti-staphylococcal phage therapy to 10 patients with DFI at high risk of amputation at two UK hospitals as part of clinical care; tolerability and efficacy were clinically assessed. FINDINGS: The opinion of the experienced clinical teams caring for these patients was that 9 of the 10 patients appeared to benefit from adjunctive phage therapy. No adverse effects were reported by clinicians or patients. In 6 of 10 patients the clinical impression was that phage therapy facilitated clinical resolution of infection and limb salvage. Resolution of soft tissue infection was observed in a 7th patient but unresolved osteomyelitis required amputation. An 8th patient demonstrated eradication of Staphylococcus aureus from a polymicrobial infection and a 9th showed signs of clinical improvement before early cessation of phage therapy due to an unrelated event. One patient, with a weakly susceptible S aureus isolate, had no significant response. IMPLICATIONS: This report describes the largest application of phage therapy in the United Kingdom to date and the first application of phage therapy for DFI in the United Kingdom and offers subjective hints toward impressive tolerability and efficacy. Phage therapy has the potential to transform the prevention and treatment of DFIs.

Case report: Analysis of phage therapy failure in a patient with a Pseudomonas aeruginosa prosthetic vascular graft infection.

Clinical case of a patient with a Pseudomonas aeruginosa multidrug-resistant prosthetic vascular graft infection which was treated with a cocktail of phages (PT07, 14/01, and PNM) in combination with ceftazidime-avibactam (CZA). After the application of the phage treatment and in absence of antimicrobial therapy, a new P. aeruginosa bloodstream infection (BSI) with a septic residual limb metastasis occurred, now involving a wild-type strain being susceptible to ß-lactams and quinolones. Clinical strains were analyzed by microbiology and whole genome sequencing techniques. In relation with phage administration, the clinical isolates of P. aeruginosa before phage therapy (HE2011471) and post phage therapy (HE2105886) showed a clonal relationship but with important genomic changes which could be involved in the resistance to this therapy. Finally, phenotypic studies showed a decrease in Minimum Inhibitory Concentration (MIC) to ß-lactams and quinolones as well as an increase of the biofilm production and phage resistant mutants in the clinical isolate of P. aeruginosa post phage therapy.

Eudragit® FS Microparticles Containing Bacteriophages, Prepared by Spray-Drying for Oral Administration.

Phage therapy is recognized to be a promising alternative to fight antibiotic-resistant infections. In the quest for oral dosage forms containing bacteriophages, the utilization of colonic-release Eudragit® derivatives has shown potential in shielding bacteriophages from the challenges encountered within the gastrointestinal tract, such as fluctuating pH levels and the presence of digestive enzymes. Consequently, this study aimed to develop targeted oral delivery systems for bacteriophages, specifically focusing on colon delivery and employing Eudragit® FS30D as the excipient. The bacteriophage model used was LUZ19. An optimized formulation was established to not only preserve the activity of LUZ19 during the manufacturing process but also ensure its protection from highly acidic conditions. Flowability assessments were conducted for both capsule filling and tableting processes. Furthermore, the viability of the bacteriophages remained unaffected by the tableting process. Additionally, the release of LUZ19 from the developed system was evaluated using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) model. Finally, stability studies demonstrated that the powder remained stable for at least 6 months when stored at +5 °C.

Characterization of a Bacteriophage GEC_vB_Bfr_UZM3 Active against Bacteroides fragilis.

Bacteroides fragilis is a commensal gut bacterium that is associated with a number of blood and tissue infections. It has not yet been recognized as one of the drug-resistant human pathogens, but cases of the refractory infections, caused by strains that are not susceptible to the common antibiotic regimes established for B. fragilis, have been more frequently reported. Bacteriophages (phages) were found to be a successful antibacterial alternative to antibiotic therapy in many cases of multidrug-resistant (MDR) bacterial infections. We have characterized the bacteriophage GEC_vB_Bfr_UZM3 (UZM3), which was used for the treatment of a patient with a chronic osteomyelitis caused by a B. fragilis mixed infection. Studied biological and morphological properties of UZM3 showed that it seems to represent a strictly lytic phage belonging to a siphovirus morphotype. It is characterized by high stability at body temperature and in pH environments for about 6 h. Whole genome sequencing analysis of the phage UZM3 showed that it does not harbor any known virulence genes and can be considered as a potential therapeutic phage to be used against B. fragilis infections.

Successful Bacteriophage-Antibiotic Combination Therapy against Multidrug-Resistant Pseudomonas aeruginosa Left Ventricular Assist Device Driveline Infection.

There is considerable interest in the use of bacteriophages (phages) to treat Pseudomonas aeruginosa infections associated with left ventricular assist devices (LVADs). These infections are often challenging to manage due to high rates of multidrug resistance and biofilm formation, which could potentially be overcome with the use of phages. We report a case of a 54-year-old man with relapsing multidrug-resistant P. aeruginosa LVAD driveline infection, who was treated with a combination of two lytic antipseudomonal phages administered intravenously and locally. Treatment was combined with LVAD driveline repositioning and systemic antibiotic administration, resulting in a successful outcome with clinical cure and eradication of the targeted bacteria. However, laboratory in vitro models showed that phages alone could not eradicate biofilms but could prevent biofilm formation. Phage-resistant bacterial strains evolved in biofilm models and showed decreased susceptibility to the phages used. Further studies are needed to understand the complexity of phage resistance and the interaction of phages and antibiotics. Our results indicate that the combination of phages, antibiotics, and surgical intervention can have great potential in treating LVAD-associated infections. More than 21 months post-treatment, our patient remains cured of the infection.

Foundation of the Belgian Society for Viruses of Microbes and Meeting Report of Its Inaugural Symposium.

The Belgian Society for Viruses of Microbes (BSVoM) was founded on 9 June 2022 to capture and enhance the collaborative spirit among the expanding community of microbial virus researchers in Belgium. The sixteen founders are affiliated to fourteen different research entities across academia, industry and government. Its inaugural symposium was held on 23 September 2022 in the Thermotechnical Institute at KU Leuven. The meeting program covered three thematic sessions launched by international keynote speakers: (1) virus-host interactions, (2) viral ecology, evolution and diversity and (3) present and future applications. During the one-day symposium, four invited keynote lectures, ten selected talks and eight student pitches were given along with 41 presented posters. The meeting hosted 155 participants from twelve countries.

Isolation and Characterization of Lytic Pseudomonas aeruginosa Bacteriophages Isolated from Sewage Samples from Tunisia.

Bacteriophages could be a useful adjunct to antibiotics for the treatment of multidrug-resistant Pseudomonas aeruginosa infections. In this study, lytic P. aeruginosa myoviruses PsCh, PsIn, Ps25, and Ps12on-D were isolated from Tunisian sewage samples. Phage Ps12on-D displayed an adsorption time of ~10 min, a short latency period (~10 min), and a large burst size (~115 PFU per infected cell) under standard growth conditions. All phages were active at broad temperature (4 °C to 50 °C) and pH (3.0 to 11.0) ranges and were able to lyse a wide variety of P. aeruginosa strains isolated from clinical and environmental samples worldwide. Illumina sequencing revealed double-stranded DNA genomes ranging from 87,887 and 92,710 bp with high sequence identity to Pseudomonas phage PAK_P1. All four phages based on sequence analysis were assigned to the Pakpunavirus genus. The presented characterization and preclinical assessment are part of an effort to establish phage therapy treatment as an alternative strategy for the management of multidrug-resistant P. aeruginosa infections in Tunisia.

Determination of phage susceptibility as a clinical diagnostic tool: A routine perspective.

As the global burden of disease caused by multidrug resistant bacteria is a major source of concern, credible clinical alternatives to antibiotic therapy, such as personalized phage therapy, are actively explored. Although phage therapy has been used for more than a century, the issue of an easy to implement diagnostic tool for determining phage susceptibility that meets current routine clinical needs is still open. In this Review, we summarize the existing methods used for determining phage activity on bacteria, including the three reference methods: the spot test, the double agar overlay plaque assay, and the Appelmans method. The first two methods rely on the principle of challenging the overnight growth of a lawn of bacteria in an agar matrix to a known relative phage to bacteria concentration and represent good screening tools to determine if the tested phage can be used for a "passive" and or "active" treatment. Beside these methods, several techniques, based on "real-time" growth kinetics assays (GKA) have been developed or are under development. They all monitor the growth of clinical isolates in the presence of phages, but use various detection methods, from classical optical density to more sophisticated techniques such as computer-assisted imagery, flow-cytometry, quantitative real-time polymerase chain reaction (qPCR) or metabolic indicators. Practical considerations as well as information provided about phage activity are reviewed for each technique. Finally, we also discuss the analytical and interpretative requirements for the implementation of a phage susceptibility testing tool in routine clinical microbiology.

Bacteriophage-antibiotic combination therapy against extensively drug-resistant Pseudomonas aeruginosa infection to allow liver transplantation in a toddler.

Post-operative bacterial infections are a leading cause of mortality and morbidity after ongoing liver transplantation. Bacteria causing these infections in the hospital setting can exhibit high degrees of resistance to multiple types of antibiotics, which leads to major therapeutic hurdles. Alternate ways of treating these antibiotic-resistant infections are thus urgently needed. Phage therapy is one of them and consists in using selected bacteriophage viruses - viruses who specifically prey on bacteria, naturally found in various environmental samples - as bactericidal agents in replacement or in combination with antibiotics. The use of phage therapy raises various research questions to further characterize what determines therapeutic success or failure. In this work, we report the story of a toddler who suffered from extensively drug-resistant Pseudomonas aeruginosa sepsis after liver transplantation. He was treated by a bacteriophage-antibiotic intravenous combination therapy for 86 days. This salvage therapy was well tolerated, without antibody-mediated phage neutralization. It was associated with objective clinical and microbiological improvement, eventually allowing for liver retransplantation and complete resolution of all infections. Clear in vitro phage-antibiotic synergies were observed. The occurrence of bacterial phage resistance did not result in therapeutic failure, possibly due to phage-induced virulence tradeoffs, which we investigated in different experimental models.