Skin, soft tissue and systemic bacterial infections following aquatic injuries and exposures

Analysis of clinical characteristics of infections caused by Shewanella species

PURPOSE

The Shewanella genus is a rare pathogen of marine origin. In recent years, there has been a continuous increase in infection cases caused by this bacterium, and we have observed the uniqueness of infections caused by this microorganism.

MATERIALS AND METHODS

This study conducted a retrospective analysis of the medical history and laboratory examination data of patients infected with the Shewanella genus over the past decade. Additionally, it employed bioinformatics methods to analyze the relevant virulence factors and antibiotic resistance genes associated with the Shewanella genus.

RESULTS

Over the past 10 years, we have isolated 51 cases of Shewanella, with 68.82% being Shewanella putrefaciens (35/51 cases) and 31.37% being Shewanella algae (16/51 cases). Infected individuals often had underlying diseases, with 39.22% (20/51) having malignant tumors and 25.49% (13/51) having liver and biliary system diseases primarily characterized by stones. The majority of patients, 62.74% (32/51), exhibited mixed infections, including one case with a combination of infections from three other types of bacteria and five cases with a combination of infections from two other types of bacteria. The identified microorganisms were commonly resistant to ticarcillin-clavulanic acid (23.5%), followed by cefoperazone-sulbactam (19.6%), ciprofloxacin (17.6%), and cefotaxime (17.6%). Bioinformatics analysis indicates that Shewanella can express bile hydrolysis regulators and fatty acid metabolism regulators that aid in adapting to the unique environment of the biliary tract. Additionally, it expresses abundant catalase, superoxide dismutase, and two-component signal transduction system proteins, which may be related to environmental adaptation. Shewanella also expresses various antibiotic resistance genes, including beta-lactamases and aminoglycoside modification enzymes. Iron carriers may be one of its important virulence factors.

CONCLUSIONS

We speculate that the Shewanella genus may exist as a specific colonizer in the human body, and under certain conditions, it may act as a pathogen, leading to biliary infections in the host.

Marine Envenomation in Okinawa: Overview and Treatment Concept

Okinawa prefecture is a popular tourist destination due to its beaches and reefs. The reefs host a large variety of animals, including a number of venomous species. Because of the popularity of the reefs and marine activities, people are frequently in close contact with dangerous venomous species and, thus, are exposed to potential envenomation. Commonly encountered venomous animals throughout Okinawa include the invertebrate cone snail, sea urchin, crown-of-thorns starfish, blue-ringed octopus, box jellyfish, and fire coral. The vertebrates include the stonefish, lionfish, sea snake, and moray eel. Treatment for marine envenomation can involve first aid, hot water immersion, antivenom, supportive care, regional anesthesia, and pharmaceutical administration. Information on venomous animals, their toxins, and treatment should be well understood by prehospital care providers and physicians practicing in the prefecture.

Enhancing Vibrio vulnificus infection diagnosis for negative culture patients with metagenomic next-generation sequencing

Objective

To evaluate the diagnostic value of metagenomic next-generation sequencing (mNGS) in Vibrio vulnificus (V. vulnificus) infection.

Methods

A retrospective analysis of patients with V. vulnificus infection at the Fifth Affiliated Hospital of Sun Yat-Sen University from January 1, 2020 to April 23, 2023 was conducted. 14 enrolled patients were diagnosed by culture or mNGS. The corresponding medical records were reviewed, and the clinical data analyzed included demographics, epidemiology laboratory findings, physical examination, symptoms at presentation, antibiotic and surgical treatment, and outcome.

Results

In this study, 78.6% (11/14) patients had a history of marine trauma (including fish stab, shrimp stab, crab splints and fish hook wounds), 7.1% (1/14) had eaten seafood, and the remaining 14.3% (2/14) had no definite cause. Isolation of V. vulnificus from clinical samples including blood, tissue, fester and secreta. 9 cases were positive for culture, 5 cases were detected synchronously by mNGS and got positive for V. vulnificus. 85.7% (12/14) cases accepted surgical treatment, with 1 patient suffering finger amputated. 14 enrolled patients received appropriate antibiotic therapy, and all of them had recovered and discharged. 9 strains V. vulnificus isolated in this study were sensitive to most beta-lactam antibiotics, aminoglycosides, quinolones, etc.

Conclusion

Vibrio vulnificus infection is a common water-exposed disease in Zhuhai, which requires identification of a number of pathogens. Of severe infections with unknown pathogen, mNGS can be used simultaneously, and the potential to detect multiple pathogens is of great help in guiding treatment.

Diagnosis and Management of Severe Water-Related Skin and Soft Tissue Sepsis: A Summative Review of the Literature

BACKGROUND

Skin and soft tissue infections (SSTIs) are common presentations in the emergency department. However, this is less common after contact with contaminated saltwater or freshwater. This review presents the diagnosis and management of water-related soft tissue sepsis in this vulnerable and difficult-to-treat subgroup of necrotizing soft tissue sepsis.

METHODS

A summative literature overview is presented regarding bacterial and fungal SSTI after contact with contaminated water, with practical diagnostic and management aspects.

RESULTS

The literature indicates that these wounds and infections remain difficult to treat. An approach using appropriate diagnostic tools with both medical and surgical management strategies is provided.

CONCLUSIONS

SSTIs due to water contamination of wounds involve unusual organisms with unusual resistance patterns, and require a nuanced and directed diagnostic approach with an adaptation of the usual antibiotic or antifungal selection to achieve a successful cure, along with aggressive debridement and wound care.

Antimicrobial efficacy of composite irrigation solution against dominant pathogens in seawater immersion wound and in vivo wound healing assessment

Seawater immersion wound is inevitably accompanied by bacterial infection. Effective irrigation is critical for bacterial infection prevention and wound healing. In this study, the antimicrobial efficacy of a designed composite irrigation solution against several dominant pathogens in seawater immersion wounds was evaluated, and in vivo wound healing assessment was conducted in a rat model. According to the time-kill result, the composite irrigation solution exhibits excellent and rapid bactericidal effect against Vibrio alginolyticus and Vibrio parahaemolyticus within 30 s of treatment while eliminating Candida albicans, Pseudomonas aeruginosa, Escherichia coli, and the mixed microbes after 1 h, 2 h, 6 h, and 12 h of treatment, respectively. Significant bacterial count reduction of Staphylococcus aureus was observed after 5 h treatment. In addition to its skin non-irritating attribute, the in vivo wound healing results further demonstrated that the irrigation solution showed high repair efficiency in the skin defect model inoculated with the mixed microbes. The wound healing rate was significantly higher than that of the control and normal saline groups. It could also effectively reduce the number of viable bacteria on the wound surface. The histological staining indicated that the irrigation solution could reduce inflammatory cells and promote collagen fibers and angiogenesis, thereby promoting wound healing. We believed that the designed composite irrigation solution has great potential for application in the treatment of seawater immersion wounds.

Mycobacterium marinum: A Challenging Cause of Protracted Tenosynovitis

Mycobacterium marinum infections are rare, and they can be difficult to diagnose and treat. This may lead to further spread of the infection and complications, such as tenosynovitis, pyomyositis, and osteomyelitis. A 40-year-old previously healthy man presented with tenosynovitis of the extensor tendons on the second phalanx of his right hand. He was initially treated with steroid injections without any effect. Followingly, ulceration and an abscess developed on the dorsal site of the hand. At this point, it came to the physician's knowledge that the patient had been cleaning an aquarium before onset of symptoms. After progression to massive tenosynovitis, the patient was admitted and underwent multiple surgical debridements. Briefly, after the first surgery, an interferon-γ release assay was positive, and treatment for M. marinum with rifampicin and azithromycin was initiated after eight months of symptoms. Later, a surgical biopsy showed acid-fast bacilli, and a polymerase chain reaction confirmed the diagnosis of M. marinum. In this case story, we highlight the difficulties of diagnosing and managing this complicated infection, describe the considerable morbidity associated with it, and suggest that local tissue concentrations could be useful to improve clinical outcomes, as these concentrations are potentially suboptimal.

Multi-crosslinked hydrogels with strong wet adhesion, self-healing, antibacterial property, reactive oxygen species scavenging activity, and on-demand removability for seawater-immersed wound healing

In general, seawater-immersed wounds are associated with tissue necrosis, infection, prolonged healing period, and high mortality because of high salinity, hyperosmosis, and the presence of various pathogenic bacteria in seawater. However, current wound dressings can hardly achieve strong and stable wet adhesion and antibacterial properties, thus limiting their application to seawater-immersed wounds. Here a multifunctional hydrogel (OD/EPL@Fe) comprising catechol-modified oxidized hyaluronic acid (OD), ε-poly-L-lysine (EPL), and Fe³⁺ was prepared primarily through Schiff-base reaction, metal chelation, cation-π, and electrostatic interaction. The hydrogel with high wet adhesion (about 78 kPa) was achieved by combining the mussel-inspired strategy, dehydration effect, and cohesion enhancement, which is higher than that of commercial fibrin glues and cyanoacrylate glues. Meanwhile, the hydrogel can eliminate Marine bacteria (V. vulnificus and P. aeruginosa) and inhibit their biofilm formation. In addition, the hydrogel demonstrated injectability, self-healing, reactive oxygen species scavenging activity, photothermal effect, seawater isolation, on-demand removal, and hemostatic properties. In vivo results showed that the hydrogel had good adhesion to dynamic wounds in a rat neck full-thickness skin wound model. In particular, the hydrogel exhibited antibacterial, anti-inflammatory, and antioxidant properties in a rat seawater-immersed infected wound model and accelerated the reconstruction of skin structure and functions. The results demonstrated that the OD/EPL@Fe would be a potential wound dressing for seawater-immersed wound healing. STATEMENT OF SIGNIFICANCE: A multifunctional OD/EPL@Fe hydrogel has been prepared for the treatment of seawater-immersed wounds. The hydrogel with high wet adhesion was achieved by combining the mussel-inspired strategy, dehydration effect, and cohesion enhancement. The results revealed that the wet adhesion value of hydrogel was about eight times greater than commercial fibrin glues and 1.5 times greater than commercial cyanoacrylate glues. The hydrogel can be easily removed after being sprayed with deferoxamine mesylate. Notably, the inherent antimicrobial material of the hydrogel combined with the photothermal effect can eliminate marine bacteria and inhibit their biofilm formation. Moreover, the hydrogel can accelerate the healing of seawater-immersed infected wound on mice.

Bacteremia With Oral Prevotella Salivae in an 18-Year-Old After a Water Skiing Fall Into a Freshwater Lake

Freshwater exposure is associated with a diverse range of infections from pathogens present in soil and water. This includes skin and soft tissue infections and wound infections, gastrointestinal infections, and central nervous system infections acquired through recreational exposure or trauma. Case reports of freshwater-associated infections typically focus on waterborne pathogens as the cause of illness; however, patients who experience significant physical trauma during freshwater exposure may also be at increased risk for infection with their own flora if the nature of the injury allows entry of bacteria through a mechanism such as mucosal injury. Here, we present a case of a healthy 18-year-old man who rapidly developed bacteremia with oral flora following several falls submerging his face into lake water while water skiing, as well as acute polymicrobial sinusitis and subsequent pre-septal cellulitis. Shortly after his water skiing falls, the patient developed sinusitis that rapidly progressed to headaches, emesis, and significant periorbital swelling. Blood cultures grew Prevotella salivae, a bacterium naturally found in the oral cavity. Sinus cultures grew Klebsiella aerogenes and Listeria monocytogenes, which may be associated with lake water. The infection improved with antibiotic therapy, and the patient was discharged on a regimen of amoxicillin/clavulanic acid and trimethoprim-sulfamethoxazole. Reports of bacteremia with oral flora following freshwater injury are not typically reported, and to our knowledge, this is the first report describing bacteremia with P salivae.

Envenoming by a Marine Blood Worm (Glycera)

Bites from venomous marine annelid ‘bloodworms’ (e.g., Glycera spp.) do not appear to have been described in the medical literature despite being seemingly well-known to bait diggers and fishermen. The few laboratory study reports describe their venom composition and physiological effects in vitro to be primarily proteolytic enzymes and neurotoxins apparently used for predation and defense. Herein, we present the report of a symptomatic envenoming suffered by a marine ecologist bitten while performing her field research. The local effects included a rapid onset of pain, swelling, and numbness at the bite site “as if injected with local anesthetic”. Additional signs and symptoms appearing over a two-week period were consistent with both delayed venom effects and potentially secondary infection. The late signs and symptoms resolved during a course of antibiotic treatment with doxycycline prescribed as a precaution and lack of resources to consider a wound culture. Comments about annelid bites sporadically appear in the popular literature, especially pertaining to the fishing industry, under names such as ‘bait-diggers hand’. While these bites are not known to be dangerously venomous, they seem to produce painful local symptoms and possibly increase the risk of marine bacterial infections that could be associated with more serious outcomes. More cases need to be formally described to better understand the natural history of these types of envenomation.

Infections following stingray attacks: A case series and literature review of antimicrobial resistance and treatment

BACKGROUND

Injuries sustained following stingray attacks are at high risk of infection and can progress to serious, debilitating consequences for the patient if not appropriately addressed. Antibiotic treatment of such infections is important to minimise the morbidity experienced by patients. However, antibiotic guidelines relating specific to this patient group are not well established. This study aims to report the experience of a single institution at treating stingray associated wound infections and to review the literature for reported cases. Additionally, we review the microbiological risk in these patients and summarise the literature surrounding antibiotic choice.

METHODS

A retrospective review of all patients presenting with injuries sustained following stingray attacks was conducted at a single institution. Additionally, a comprehensive literature review was conducted to identify cases of infected stingray associated trauma and review the causative micro-organisms and antibiotics used to treat such infections.

RESULTS

22 cases of stingray injuries were identified from a single institution. Of these, eight infections were reported. One case grew a highly resistant Vibrio species. Among the literature, 18 cases of infections were identified many of which led to significant complications for patients. The micro-organisms identified were diverse and there was little consistency among the antibiotic regimens utilised.

CONCLUSION

Based on the antibiotic susceptibilities of causative bacteria along with extrapolation from recommendations and guidelines identified in the literature, ciprofloxacin, doxycycline and trimethoprim-sulfamethoxazole appear to be the most appropriate antibiotics choices for prophylaxis or treatment of localised infection. Antibiotic choices for the empiric treatment of systemic infection requires further research and clarification.

Evaluation and Management of Watercraft-Related Injuries for Acute Care Surgeons: Towards Improving Care and Implementing Effective Public Health Prevention Policies

Boating has exposed humans to elemental hazards for centuries. What was once a lifelong craft and time-honored skillset is now, with modern technology, a popular recreational activity. Boating safety has inherent limitations and has been historically challenging to enforce. These circumstances have given way to a rising number of watercraft-associated injuries and fatalities. This review aims to investigate the diagnosis, work-up, and management of watercraft-related injuries, including blunt mechanisms, propeller wounds, water-force trauma, associated marine infections, and submersion injuries, as well as outline gaps in current public health policy on watercraft injuries, potential interventions, and available solutions. Motorboats and personal watercraft differ in size, power modality, and differential risk for injury. Accidents aboard watercraft often share commonalities with motor vehicles and motorcycles, namely: rapid deceleration, ejection, and collision with humans. The complexity of care is added by the austere environment in which many watercraft accidents occur, as well as the added morbidity of drowning and hypothermia. Wounds can also become infected by marine organisms, which require wound care and antimicrobial therapy specific to the aquatic environment in which the injury occurred. The treatment of these patients can be further exacerbated by the prolonged transportation times due to complicated water rescue. There are many measures that can prevent or abate watercraft injuries, but inconsistent regulations and enforcement may impair the success of these interventions. Further research is needed to identify possible solutions to common causes of watercraft injuries, such as inconsistent lifejacket use and bow riding.

Aeromonas hydrophilia Infection in an Immunocompromised Host

Aeromonas hydrophila is an anaerobic, gram-negative rod-shaped bacterium that is commonly found in aquatic environments. This organism can cause a wide range of infections in humans, including gastroenteritis, septicemia, and skin and soft tissue infections. We herein describe a case of bacteremia due to Aeromonas hydrophila secondary to a soft tissue infection of the fingers that resulted in osteomyelitis in an immunocompromised patient.

Watercraft propellers as a mechanism of orthopaedic injuries: injury patterns, management, and complications

INTRODUCTION AND PURPOSE

Recreational watercraft use is popular across the United States, and there is a high rate of injury associated with the use and misuse of these vehicles. Watercraft propeller injuries represent a particularly devastating mechanism of injury. We aim to describe and analyze the range of orthopaedic injuries sustained from a watercraft propeller with a particular focus on the mechanism, injury pattern, management, and complications associated with these unique, high-energy injuries.

MATERIALS AND METHODS

A retrospective review of 42 patients who sustained injuries from watercraft propeller that presented to a level 1 trauma center was performed. Data collected included patient demographics, mechanism of injury, surgical management, antibiotic use, and complications.

RESULTS

Forty-two patients sustained 96 fractures. Ninety-one fractures (94.8%) were open and 5(5.2%) were closed. Twenty (20.8%) were of the upper extremity, 70(72.9%) were of the lower extremity, and 6(6.3%) were of the pelvic ring. The majority of open fractures were Gustilo-Anderson Type IIIA or greater (54, 59.3%). There were 9 total infections affecting 8 of 96 fracture sites (cumulative risk of 8.3%), and other complications included stiffness (3), heterotopic ossification (1), non-union (1), flap failure (1), DVT (2), PE (1), and systemic infection (1) for a total of 19 complications.

CONCLUSIONS

Watercraft propellers often result in devastating injuries with high rates of morbidity. The high rate of open fractures and neurovascular injury, necessity for multiple surgeries, and extended length of hospital stay show the need for continued awareness about boat safety and the danger of propellers.

Leclercia adecarboxylata causing necrotising soft tissue infection in an immunocompetent adult

A 72-year-old woman presented with concern for a necrotising soft tissue infection (NSTI) 6 days after a tree branch impaled her left lower extremity while hiking in Hawaii. The wound was irrigated and closed at a local clinic in Hawaii. She completed a 5-day course of clindamycin. She presented to our emergency department 1 day after completion of antibiotics due to worsening erythema and malodorous drainage. Local wound exploration revealed bullae and easy dissection of fascial planes. CT scan revealed complex heterogeneous fluid and inflammatory stranding in the posterior calf. Clinical and radiographic findings raised concern for NSTI prompting initiation of broad spectrum antibiotics and urgent operative debridement. Wound cultures and deep tissues cultures returned positive for pansusceptible Leclercia adecarboxylata She underwent two additional operative debridements and transitioned to negative pressure wound therapy during her hospitalisation. She was discharged home on oral amoxicillin/clavulanate on hospital day 6.

Edwardsiella tarda as a Cause for Limb- and Life- threatening Soft Tissue Infections: What All Plastic Surgeons Need to Know

Edwardsiella tarda (ET), a Gram-negative bacterium, causes an extremely uncommon, yet highly aggressive, soft tissue infection. Although plastic surgeons are frequently involved in the primary care, debridement, and secondary reconstruction of difficult soft tissue infections, infections caused by ET have received scant attention in the plastic surgery literature, perhaps because of the rarity of occurrence. We present a case of a 58-year-old man with alcohol abuse and hepatitis C who developed an upper extremity soft tissue infection after a catfish injury, which rapidly deteriorated to cause multiorgan failure and death within 5 days of admission. We will discuss the management of this rare but potentially lethal infection as well as the review of the current literature.

Prolonged Brackish Water Exposure: A Case Report

Exposure to and consumption of brackish water are associated with an elevated risk of infection, hypernatremia, and hypothermia. Minimal data exist to support the diagnosis and treatment of patients with long-term brackish water exposure. We present a case of a patient who spent 5 to 10 d semisubmerged in the Elizabeth River in coastal Virginia. A 55-y-old male presented via ambulance after 5 to 10 d of being "stuck in the mud." He was hypernatremic, with a sodium of 176 mEq·L^-1, hypothermic to 34.5°C (94.1°F), and hypotensive at 88/50 mm Hg, with a sodium concentration of 176 mEq·L^-1 and an osmolality of 412 mosm·kg^-1. He developed pneumonia, with respiratory cultures growing Vibrio parahemolyticus, Klebsiella oxytoca, and Shewanella algae. He had pustules, which grew Aeromonas hydrophilia and Aeromonas caviae. A nasogastric tube was placed. Using suction, 500 mL of coarse sand and gravel was removed from his stomach. Antibiotics and intravenous fluids were given. The patient fully recovered after 3 wk and was discharged to rehabilitation. Exposure to brackish water can present a unique set of infectious and metabolic complications. Initial care should include treatment of metabolic derangements, such as hypovolemia, hypernatremia, and hypothermia, and treatment of infections with antibiotics based on knowledge of the most likely causative organisms.

Infecção marinha

Introdução: Cidades litorâneas possuem atividades econômicas como a pesca e o turismo que promovem o contato com a água do mar e, consequentemente, a exposição a microrganismos raramente encontrados em outros contextos e muitas vezes de diagnóstico tardio, podendo resultar em morbidade ou morte significativa. Objetivo: Essa revisão da literatura objetiva mostrar a importância da suspeição da infecção marinha na Atenção Primária, sua etiologia, manifestações clínicas, tratamento, complicações e prevenção. Métodos: Foi realizada pesquisa em bases de dados eletrônicos (SciELO, Google Acadêmico, MEDLINE e PubMed). Resultados: Foram encontrados 135 artigos e vinte foram selecionados, referentes aos anos de 2003 a 2018. Observou-se escassez de estudos que avaliam a efetividade de esquemas de antibioticoterapia e sua duração necessária. Além disso, verificou-se a ausência de classificação no Código Internacional de Doenças (CID-10) e Descritores em Ciências da Saúde (DeCS), fato que prejudica a notificação e estudos epidemiológicos sobre o assunto. Conclusão: É preciso incluir a infecção marinha no diagnóstico diferencial de casos de ferimentos crônicos de difícil diagnóstico, principalmente se houver histórico de exposição a ambiente marinho. Novos estudos se fazem necessários para avaliação da terapêutica adequada. Outrossim, é fundamental conscientizar a população quanto ao risco de infecção marinha e seus métodos de prevenção.

Severe Sepsis and Wet Gangrene Requiring Foot Amputation Caused by an Emerging Human Pathogen - Shewanella algae

A 69-year-old woman with type 2 diabetes mellitus, peripheral vascular disease, and other comorbidities presented with recurrent syncopal episodes. Cellulitic skin changes in her right lower extremity were noted, as well as a large hemorrhagic bulla on the dorsum of her right foot. Severe sepsis was determined to be the reason for her syncopal episodes. Blood cultures and the bulla aspirate culture were positive for Shewanella algae that was pan-sensitive to antibiotics. Her clinical status was stabilized with a regimen of intravenous fluids and broad-spectrum antibiotics. However, due to the development of right foot gangrene, she underwent debridement and eventually required transmetatarsal open amputation.

Aquatic Orthopaedic Injuries

Extremity injuries sustained in aquatic environments require unique considerations compared with injuries sustained on land. Knowledge of these considerations is becoming more important as aquatic recreational activities increase in popularity. Aquatic injuries may occur through mechanical contact with a variety of different objects or surfaces, such as a recreational device or watercraft part, or may occur through contact with marine animals. Marine animal injuries can be further categorized into bites, stings, or blunt contact, as well as venomous or nonvenomous, distinctions that should be used to guide clinical management. Numerous instances of retained foreign bodies after marine animal stings exist, which can result in infection and prolonged envenomization; thus, radiographic examination should be routinely performed in aquatic sting injuries to prevent these harmful sequelae. Any aquatic injury resulting in an open wound has an increased risk for infection, and prophylactic antibiotics must be given with consideration for the unique microbiologic flora of the aquatic environment.

In Vitro Antimicrobial Activities of Commercially Available Tea Tree (Melaleuca alternifolia) Essential Oils

Melaleuca alternifolia tea tree oil (TTO) is largely used in cutaneous infections. Clinical observations reported antibacterial, antifungal, and antiviral activities, whereas in vitro experiments ascribed most of biological properties to terpinen-4-ol. Since different plant chemotypes and storage conditions result in variations of chemical composition of commercially available TTO, in this study we investigated the antimicrobial activity and the chemical profile of ten commercially available TTO products. The antimicrobial activity was assessed against Candida glabrata, Herpes simplex virus type 1 (HSV-1), methicillin-resistant Staphylococcus aureus (MRSA), and Pseudomonas aeruginosa grown in planktonic mode or biofilms. Only five out of ten TTO batches reported significant antimicrobial activity. The identified TTO products reduced bacterial survival in biofilms, generated oxidative damage in C. glabrata, and diminished HSV-1 infectivity. GC-MS analysis revealed that all the analyzed TTO batches fitted into the terpinen-4-ol chemotype even if we reported great variability in composition of nine major ISO-specified TTO components. Overall, we were not able to ascribe the antimicrobial activity to the content in terpinen-4-ol. We therefore conclude that the antimicrobial activity of TTO results from complex interaction among different components.

Preparation of hydroxylated lecithin complexed iodine/carboxymethyl chitosan/sodium alginate composite membrane by microwave drying and its applications in infected burn wound treatment

Improving the antibacterial properties of membrane wound dressings of natural polymers is crucial. Iodine is an important safe inorganic antibacterial agent, but was confined in the composition with polymer membranes due to the challenges of homogeneity and stability during drying. In the present work, iodine was complexed with hydroxylated lecithin (HL) to improve its stability and complexing efficiency for the composition with carboxymethly chitosan/sodium alginate. With the aid of microwave drying, hydroxylated lecithin complexed iodine/carboxymethly chitosan/sodium alginate (HLI/CMCS/SA) composite membranes with homogeneously distributions of HLI, high contents of activated iodine, good mechanical and swelling properties, proper water vapor permeability, pH controllable iodine release and excellent antibacterial properties were prepared. The composite membranes exhibited high repairing efficiencies for the infection of a rat model of the seawater immersed wound infection of deep partial-thickness burns. This novel antibacterial composite membrane can be potentially used as a high performance wound dressing for treating and repairing open trauma infections.

Infectious Diseases After Hydrologic Disasters

Hydrologic disasters, including hurricanes, tsunamis, and severe flooding, have been associated with infectious diseases, particularly among vulnerable and displaced populations in resource-poor settings. Skin and soft tissue infections, gastrointestinal infections, respiratory infections, zoonotic infections, and vector-borne diseases each present unique threats to human health in this setting. Increased emergency physician awareness of these infectious diseases and their diagnosis and management helps optimize medical care for survivors after a hydrologic disaster and safeguard the health of disaster responders.

Orthopaedic Watercraft Injuries: Characterization of Mechanisms, Fractures, and Complications in 216 Injuries

OBJECTIVE

To review the orthopaedic injuries from watercraft treated surgically at our institution and report the mechanisms, fractures, and complications encountered.

DESIGN

Retrospective case series.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

There were 216 fractures from watercraft in 146 patients. Average age was 33 years (range 4-78 years), there were 68% males (99/146), and 16% of the injuries occurred in children.

INTERVENTION

Operative fracture fixation.

MAIN OUTCOME MEASUREMENTS

After IRB approval, data were collected from January 1, 1998, to December 31, 2015, for patients including demographics, watercraft type, mechanism of injury, fracture pattern, infection, organisms, union, and amputation. Descriptive statistics were used.

RESULTS

There were 130 closed fractures (60%) and 86 open fractures (40%). There were 146 (67%) lower extremity injuries, 49 (23%) upper extremity injuries, and 21 (10%) pelvic injuries. The overall postoperative infection rate was 9% (20/216) and was commonly polymicrobial in nature. The postoperative infection rate in closed fractures was 4% (5/130) and the postoperative infection rate in open fractures was 17% (15/86). Open fractures also had a high proportion of nonunion (8%) and amputation (16%).

CONCLUSIONS

This is the largest reported series of orthopaedic injuries from watercraft. These injuries can be devastating in nature and difficult to manage, particularly when they are open (40%). There is a high rate of postoperative infection (17%), nonunion (8%), and amputation (16%) associated with open orthopaedic watercraft fractures.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The antibacterial effect of topical ozone on the treatment of MRSA skin infection

Skin can be infected by many types of microorganisms, most commonly by gram‑positive strains of Staphylococcus and Streptococcus spp. Treatment of Staphylococcus aureus (S. aureus) infections, particularly that of methicillin resistant Staphylococcus aureus (MRSA), is a challenge in clinical practice. Ozone therapy has proven to be one of the strongest antiseptics against the majority of microorganisms involved in skin infections. The purpose of the present study was to evaluate the microbicidal effects of topical ozone therapy on S. aureus and MRSA, and determine the clinical efficacy of ozone therapy on patients with MRSA skin infection. Microbicidal effects of ozonated oil and ozonated water were determined by plating and Kirby Bauer methods. Clinical efficacy and safety of topical ozone were evaluated in two cases with skin MRSA infection. The killing rates of ozonated oil for S. aureus and MRSA were greater when compared with the control oil group. Almost 100% of S. aureus were eliminated by ozonated oil following 5 min. Almost 100% MRSA were eliminated by ozonated oil following 15 min. In addition, 100% S. aureus and 100% MRSA were eliminated by ozonated water in 1 min. The inhibition zone diameters of ozonated oil for S. aureus and MRSA were 17 and 13 mm, respectively, which were significantly larger than the control group. Both cases of skin MRSA infection were completely healed with ozone therapy. In conclusion, ozone therapy is a potential treatment for S. aureus and MRSA skin infection as it has great efficacy, few side effects and low‑costs.

Skin and Soft Tissue Infections

The skin is colonized by a diverse collection of microorganisms which, for the most part, peacefully coexist with their hosts. Skin and soft tissue infections (SSTIs) encompass a variety of conditions; in immunocompromised hosts, SSTIs can be caused by diverse microorganisms-most commonly bacteria, but also fungi, viruses, mycobacteria, and protozoa. The diagnosis of SSTIs is difficult because they may commonly masquerade as other clinical syndromes or can be a manifestation of systemic disease. In immunocompromised hosts, SSTI poses a major diagnostic challenge, and clinical dermatological assessment should be initially performed; to better identify the pathogen and to lead to appropriate treatment, etiology should include cultures of lesions and blood, biopsy with histology, specific microbiological analysis with special stains, molecular techniques, and antigen-detection methodologies. Here, we reviewed the epidemiology, pathophysiology, clinical presentation, and diagnostic techniques, including molecular biological techniques, used for SSTIs, with a focus on the immunocompromised host, such as patients with cellular immunodeficiency, HIV, and diabetic foot infection.

Shewanella species as the origin of blaOXA-48 genes: insights into gene diversity, associated phenotypes and possible transfer mechanisms

Chromosome-encoded beta-lactamases of Shewanella spp. have been indicated as probable progenitors of bla_OXA-48-like genes. However, these have been detected in few Shewanella spp. and dissemination mechanisms are unclear. Thus, our main objective was to confirm the role of Shewanella species as progenitors of bla_OXA-48-like genes. In silico analysis of Shewanella genomes was performed to detect bla_OXA-48-like genes and context, and 43 environmental Shewanella spp. were characterised. Clonal relatedness was determined by BOX-PCR. Phylogenetic affiliation was assessed by 16S rDNA and gyrB sequencing. Antibiotic susceptibility phenotypes were determined. The bla_OXA-48-like genes and genetic context were inspected by PCR, hybridisation and sequence analysis. Gene variants were cloned in Escherichia coli and MICs were determined. Shewanella isolates were screened for integrons, plasmids and insertion sequences. Analysis of Shewanella spp. genomes showed that putative bla_OXA-48-like is present in the majority and in an identical context. Isolates presenting unique BOX profiles affiliated with 11 Shewanella spp. bla_OXA-48-like genes were detected in 22 isolates from 6 species. Genes encoded enzymes identical to OXA-48, OXA-204, OXA-181, and 7 new variants differing from OXA-48 from 2 to 82 amino acids. IS1999 was detected in 24 isolates, although not in the vicinity of bla_OXA-48 genes. Recombinant E. coli strains presented altered MICs. The presence/absence of bla_OXA-48-like genes was species-related. Gene variants encoded enzymes with hydrolytic spectra similar to OXA-48-like from non-shewanellae. From the mobile elements previously described in association with bla_OXA-48-like genes, only the IS1999 was found in Shewanella, which indicates its relevance in bla_OXA-48-like genes transfer to other hosts.

Effect of vacuum sealing drainage on the expression of VEGF and miRNA-17-5p in seawater-immersed blast-injury wounds

The aim of the present study was to compare and observe the expression levels of vascular endothelial growth factor (VEGF) and miRNA-17-5p during the treatment of seawater-immersed blast-injury wounds (SIBIW) under different conditions of vacuum sealing drainage (VSD), and to identify the optimized range of VSD treatment and partially explain its mechanisms. The bilateral hips and scapulae of experimental pigs (weight, 25-30 kg) were subjected to blast-injury wounds, followed by the seawater immersion. The animals then underwent conventional dressing treatment under 120, 180 and 240 mmHg VSD. Visual observation, in addition to histological, immunohistochemical and molecular biological techniques were applied to compare and observe the extent of wound healing and expression levels of VEGF and miRNA-17-5p. The wound healing of the VSD treatment group was improved compared with the control group, with 120 mmHg negative pressure producing the most marked effect. miR-17-5p expression was detected in the SIBIW granulation tissues. There was significant difference between each VSD treatment group and control group at each time point (P<0.05). Thus, the present results show that miR-17-5p can be expressed in SIBIW granulation tissues, and this effect is most evident under 120 mmHg negative pressure, which may inform the optimized negative range for the treatment of SIBIW.

Erysipelothrix rhusiopathiae Suppurative Arthritis in a 12-year-old Boy After an Unusual Fresh Water Exposure

We report the case of a 12-year-old boy who experienced recurrent suppurative arthritis of the distal interphalangeal joint after near simultaneous exposure to a frog, a dog bite and lake water. Anaerobic cultures of synovial fluid obtained during operative debridement grew small round gray colonies ultimately identified as Erysipelothrix rhusiopathiae by routine laboratory tests and mass spectrometry.

Can patients with a CSF shunt SCUBA dive?

BACKGROUND

Shunt placement for cerebrospinal fluid (CSF) diversion is one of the most commonly performed procedures in neurosurgery. Pleasure or sports diving is a popular sport enjoyed by millions. At present, no guidelines exist to affirm the safety of diving in the presence of a CSF shunt.

METHODS

Literature search and review of medical fitness regulations used by diving organisations.

RESULTS

Although the available evidence is anecdotal, no reports of shunt-related complications exist and in vitro studies show lasting functionality.

CONCLUSIONS

Patients with CSF shunts should undergo careful evaluation including assessment of their cognitive and physical needs as well as co-morbidities. Having a CSF shunt in situ is not in itself a contraindication to SCUBA diving.

Traumatic Amputation of Finger From an Alligator Snapping Turtle Bite

Legend states that the alligator snapping turtle (Macrochelys temminckii) should be handled with extreme caution as it has jaw strength powerful enough to bite a wooden broomstick in half. Tales of bite injuries from what is the largest freshwater turtle in North America exist anecdotally, yet there are few descriptions of medical encounters for such. The risk of infection from reptilian bites to the hand in an aquatic environment warrants thorough antibiotic treatment in conjunction with hand surgery consultation. We present the first case report of a near total amputation of an index finger in an adolescent boy who had been bitten by a wild "gator snapper."