Infectious Complications After Battlefield Injuries: Epidemiology, Prevention, and Treatment

PLGA Nanoparticles Formulations Loaded With Antibiotics Induce Sustained and Controlled Antibiotics Release for Prolonged Antibacterial Action Against MRSA, and Pseudomonas aeruginosa FRD1

The purpose of the present study was to create resorbable nanoparticles (NPs) using poly(lactic-co-glycolic acid) (PLGA) to develop novel antibacterial therapeutics for the treatment of chronic wound infections that are susceptible to recurrent infections. By first performing a release study, it was possible to predict the behavior of the different PLGA NP formulations and assess the efficacy of the nanocomposite drug delivery system. These PLGA NP formulations consisted of varying ratios of PLGA without polyvinyl alcohol (PVA) and PLGA with PVA (PLGA-PVA) (i.e., 25:75[PLGA25], 50:50[PLGA50], and 75:25[PLGA75]). Then, different antibiotics (i.e., ciprofloxacin and gentamicin) were incorporated into the PLGA NP formulations to test the antibacterial efficacy of these antimicrobial NPs against different pathogens (i.e., methicillin-resistant Staphylococcus aureus USA300 [MRSA], Pseudomonas aeruginosa FRD1, and Acinetobacter baumannii BAA1605). Of particular interest was testing against the MRSA strain USA300 and the P. aeruginosa strain FRD1. This was possible by measuring the zone of inhibition. A 3-day period was used to monitor the antibacterial efficacy of the different PLGA NP formulations (i.e., PLGA25, PLGA50, and a 1:1 combination of PLGA25:PLGA50) against A. baumannii BAA1605, MRSA, and P aeruginosa FRD1. Throughout the study, A. baumannii was a negative control and was resistant to all the PLGA NP formulations loaded with ciprofloxacin and gentamicin. At the end of the 3-day period, the PLGA and PLGA50 ciprofloxacin-loaded formulations produced zones of inhibition of 27 mm and 23 mm, respectively, against P. aeruginosa FRD1. This indicated that P. aeruginosa FRD1 was susceptible to both formulations. The mixed formulations with equal parts PLGA25:PLGA50 loaded with ciprofloxacin produced a zone of inhibition (i.e., 25 mm). This again indicated that P. aeruginosa FRD1 was susceptible to ciprofloxacin. The formulations tested against MRSA showed that only gentamicin-loaded formulations produced intermediate results, and that ciprofloxacin-loaded formulations were ineffective. The PLGA25 and the PLGA50 NP formulations loaded with gentamicin both produced zones of inhibition of 13 mm. This indicated that MRSA was intermediate to both the formulations. The PLGA25:PLGA50 loaded with gentamicin produced a zone of inhibition of 14 mm, which again showed that MRSA was intermediate to this formulation. Overall, these PLGA NP formulations showed the sustained antibacterial potential of a burst release, followed by a sustained release of antibiotics from antibiotics loaded PLGA NPs in a controlled manner. In the future, this can help prevent the emergence of recurrent infections in the treatment of chronic wounds and reduce the number of medical dressing changes.

A Review of Omadacycline for Potential Utility in the Military Health System for the Treatment of Wound Infections

INTRODUCTION

Combat-related wound infections complicate the recovery of wounded military personnel, contributing to overall morbidity and mortality. Wound infections in combat settings present unique challenges because of the size and depth of the wounds, the need to administer emergency care in the field, and the need for subsequent treatment in military facilities. Given the increase in multidrug-resistant pathogens, a novel, broad-spectrum antibiotic is desired across this continuum of care when the standard of care fails. Omadacycline was FDA-approved in 2018 for treatment of adults with acute bacterial skin and skin structure infections (ABSSSI), as well as community-acquired bacterial pneumonia (CABP). It is a broad-spectrum antibiotic with activity against gram-positive, gram-negative, and atypical bacterial pathogens, including multidrug-resistant species. Omadacycline can overcome commonly reported tetracycline resistance mechanisms, ribosomal protection proteins, and efflux pumps, and is available in once-daily intravenous or oral formulations. In this review, we discuss the potential role of omadacycline, which is included in the Department of Defense Formulary, in the context of combat wound infections.

MATERIALS AND METHODS

A literature review was undertaken for manuscripts published before July 21, 2023. This included a series of publications found via PubMed and a bibliography made publicly available on the Paratek Pharmaceuticals, Inc. website. Publications presenting primary data published in English on omadacycline in relation to ESKAPEE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Escherichia coli, and Enterobacter species) pathogens and Clostridioides difficile, including in vitro, in vivo, and clinical data were included.

RESULTS

Of 260 identified records, 66 were included for evidence review. Omadacycline has in vitro activity against almost all the ESKAPEE pathogens, apart from P. aeruginosa. Importantly, it has activity against the four most prevalent bacterial pathogens that cause wound infections in the military healthcare system: S. aureus, including methicillin-resistant S. aureus, A. baumannii, K. pneumoniae, and E. coli. In vivo studies in rats have shown that omadacycline is rapidly distributed in most tissues, with the highest tissue-to-blood concentration ratios in bone mineral. The clinical efficacy of omadacycline has been assessed in three separate Phase 3 studies in patients with ABSSSI (OASIS-1 and OASIS-2) and with CABP (OPTIC). Overall, omadacycline has an established safety profile in the treatment of both ABSSSI and CABP.

CONCLUSIONS

Omadacycline has broad-spectrum activity, the option to be orally administered and an established safety profile, making it a potentially attractive replacement for moxifloxacin in the military individual first aid kit, especially when accounting for the increasing resistance to fluoroquinolones. Further studies and clinical evaluation are warranted to support broader use of omadacycline to treat combat wound infections in the military healthcare system.

Antibiotic susceptibility patterns at the Médecins Sans Frontières (MSF) Acute Trauma Hospital in Aden, Yemen: a retrospective study from January 2018 to June 2021

Background

Antimicrobial resistance (AMR) is an urgent global health concern, especially in countries facing instability or conflicts, with compromised healthcare systems. Médecins Sans Frontières (MSF) established an acute trauma hospital in Aden, Yemen, treating mainly war-wounded civilians, and implemented an antimicrobial stewardship (AMS) programme. This study aimed to describe clinical characteristics and identify antibiotic susceptibility patterns representative of patients treated with antibiotics.

Methods

Retrospective cross-sectional study using routinely collected data from all patients treated with antibiotics in the MSF-Aden Acute Trauma hospital between January 2018 and June 2021. Routine clinical data from patients' files was entered into an AMS electronic database and microbiological data were entered into WHONET. Both databases were imported and merged in REDCap and analysed using RStudio.

Results

Three hundred and sixty-three of 481 (75%) included patients were injured by violence-related trauma. Most were men aged 19-45 years (n = 331; 68.8%). In total, 598 infections were diagnosed and treated. MDR organisms were identified in 362 (60.5%) infections in 311 (65%) patients. Skin and soft-tissue infections (SSTIs) (n = 143; 24%) were the most common, followed by osteomyelitis (n = 125; 21%) and intra-abdominal-infections (IAIs) (n = 116; 19%), and 111 (19%) secondary bloodstream infections were identified. Escherichia coli was the most frequently identified pathogen, causing IAI (n = 87; 28%) and SSTI (n = 43; 16%), while Staphylococcus aureus caused mainly osteomyelitis (n = 84; 19%). Most Gram-negatives were ESBL producers, including E. coli (n = 193; 81.4%), Klebsiella pneumoniae (n = 72; 77.4%) and Enterobacter cloacae (n = 39; 50%) while most S. aureus were methicillin resistant (n = 93; 72.6%).

Conclusions

High rates of MDR were found. This information will facilitate a comprehensive review of the empirical antibiotic treatment guidelines.

Modified intermittent low negative pressure wound therapy for complex injuries: A case series

INTRODUCTION AND IMPORTANCE

Combat wounds can be difficult to manage and can lead to disfigurement and infection. The closure of these wounds is crucial, as delayed closure also increases the risk of further complications. Military medicine has introduced negative pressure wound therapy, which modulates wounds perfectly through the microscopic and macroscopic configurations of the wound environment. It is expensive and not available worldwide, and several modifications using low cast materials were mentioned in literature.

METHODS

We present a case series of four patients using the previously mentioned modified technique in combat wound management, and discuss the results, outcome, and justification for choosing this modality of treatment. All patients underwent a thorough debridement, followed by a modified negative pressure wound treatment for three weeks, employing readily available medical devices.

RESULTS

All wounds healed successfully without complication and a simple closure was used to cover the resultant wound.

CONCLUSION

Modified NPWT with limited resources is capable of promoting healing in conflict-related wounds through multifactorial properties and transforming reconstructive methods from complex to simple procedures in areas with a shortage of medical supplies and surgeons in addition to busy operating rooms.

War-related traumatic brain injuries during the Syrian armed conflict in Damascus 2014-2017: a cohort study and a literature review

BACKGROUND

The decade-long Syrian armed conflict killed or injured more than 11% of the Syrian population. Head and neck injuries are the most frequent cause of war-related trauma, about half of which are brain injuries. Reports about Syrian brain trauma victims were published from neighboring countries; However, none are available from Syrian hospitals. This study aims to report war-related traumatic brain injuries from the Syrian capital.

METHODS

We conducted a retrospective cohort study between 2014 and 2017 at Damascus Hospital, the largest public hospital in Damascus, Syria. Target patients were the victims of combat-related traumatic brain injuries who arrived alive and were admitted to the neurosurgery department or to another department but followed by the neurosurgery team. The collected data included the mechanism, type, and site of injury based on imaging findings; types of invasive interventions; intensive-care unit (ICU) admissions; as well as neurological status at admission and discharge including several severity scales.

RESULTS

Our sample consisted of 195 patients; Ninety-six of them were male young adults, in addition to 40 females and 61 children. Injuries were caused by shrapnel in 127 (65%) cases, and by gunshots in the rest, and most of them (91%) were penetrating. Sixty-eight patients (35%) were admitted to the ICU, and 56 (29%) underwent surgery. Neurological impairment was reported in 49 patients (25%) at discharge, and the mortality rate during hospitalization was 33%. Mortality and neurological impairment associated significantly with higher values on clinical and imaging severity scores.

CONCLUSIONS

This study captured the full spectrum of war-related brain injuries of civilians and armed personnel in Syria without the delay required to transport patients to neighboring countries. Although the clinical presentation of injuries at admission was not as severe as that in previous reports, the inadequate resources (i.e., ventilators and operation rooms) and the lack of previous experience with similar injuries might have resulted in the higher mortality rate. Clinical and imaging severity scales can provide a handy tool in identifying cases with low probability of survival especially with the shortage of personal and physical resources.

Management of conflict injuries to the upper limb. Part 1: assessment and early surgical care

Upper limb injuries are common in conflict zones. The functions of the upper limb are impossible to replicate with prosthetic replacement and wherever possible attempts should be made to preserve the limb with further secondary reconstruction aimed at restoration of function. Casualty assessment, haemorrhage control and resuscitation are simultaneously undertaken at the receiving medical facility. Primary surgical management involves decontamination and debridement, skeletal stabilization, restoration of vascularity, compartment fasciotomy where indicated and wound temporization with dressings. Operative findings and interventions should be documented and if evacuation of the casualty is possible, copies should be provided in the medical records to facilitate communication in the chain of care. Secondary procedures are required for further assessment and debridement prior to planning reconstruction and definitive fracture stabilization, nerve repair, wound cover or closure.

Healing features of experimental injuries of soft tissues that contain foreign bodies in the form of fragments of military personnel uniforms

INTRODUCTION

The healing of combat wounds can be complicated by the presence of foreign bodies. The present research aimed to study the regeneration of soft tissue injuries complicated by foreign bodies in the form of fragments of military uniforms.

METHODS

60 rats were divided into four groups: intact (Int), control (Con) and two experimental (EG1, EG2). In Con, wounds were sutured without implantation of foreign bodies. A uniform consisting of 100% cotton was used as foreign bodies for EG1 and a uniform consisting of 65% cotton and 35% polyester for EG2. Histological studies were performed according to generally accepted methods. The growth factors wеre determined by ELISA.

RESULTS

In EG1, the inflammatory reaction proceeded protractedly, which complicated the development of granulation tissue. In EG2, considering the moderate inflammatory reactions, healing of the wounds became possible. The increase of the growth factors content in Con was maximal at the 15th day: basic fibroblast growth factor (bFGF)-2.2 times and vascular endothelial growth factor (VEGF)-1.6 times (p<0.001). In experimental groups, the bFGF content was maximal at the 60th day and exceeded the normal values by 1.7 times in EG1 and by 2.6 times in EG2 (p<0.001); the level of VEGF was slightly higher than that in healthy animals.

CONCLUSIONS

The study showed wound healing in all groups. The repair of injuries in rats of EG1 and EG2 was complicated by the textile implant and took longer. The dynamics of the content of growth factors reflected the impairment of wound healing processes. These violations were more pronounced in the EG1 group.