Soft Tissue Infections Research Articles

Application of Flow-through Anterolateral Thigh Perforator Flaps in Replantation of Complex Severed Limb

ObjectiveTo explore the clinical application value of flow-through anterolateral thigh perforator (ALTP) flaps in replantation of complex severed limbs. MethodsThirteen severe vascular, nerve injury, and skin or soft tissue defects in patients with complex severed limbs from August 2017 to January 2019 were enrolled in this retrospective study. The skin flap has covered the wound by using the flow-through ALTP flap technique. The main vascular defect was repaired by using the descending branch of the lateral circumflex femoral artery, and the blood supply of the transplanted limb was reconstructed. The blood supply of the flap and wound healing observed were observed after the operation. Regular follow-up was performed to observe the survival and functional recovery of the replanted limb. ResultsEleven cases of replanted limb and perforator flap survived completely. Limb shortening occurred in 3 patients owing to bone defects caused by distal amputation. After the second stage of bone transplantation, the limb length and function of those 3 patients recovered well. One case showed necrosis of the little finger after replantation of the severed palm. One case showed that the crushed forearm was severed completely. The anastomotic vascular inflammatory embolism was caused by infection and necrosis of soft tissue after replantation for 2 weeks, and then the stump wound was covered with a survived skin flap in the second stage. ConclusionThe flow-through ALTP flap technique has a good therapeutic effect on the functional reconstruction of complex severed limbs with severe skin and vascular injuries.

Antimicrobial Activity of Senna didymobotrya and Thunbergia alata Plant Extracts Against Selected Bacterial Clinical Isolates from Kericho Referral Hospital in Kenya

Bacterial infections are distributed worldwide and cause deadly infectious bacterial diseases such as skin, soft tissue and respiratory tract infections, meningitis, and tuberculosis. Bacterial infections are very common and can be easily acquired since bacteria are ubiquitous. It has challenged modern healthcare providers; conventional drugs are costly and have side effects. Therefore, alternative remedies that are easily available, affordable, and effective are needed. This study was carried out to determine the antimicrobial activity of Senna didymobotrya and Thunbergia alata crude plant extracts against Staphylococcus aureus, Streptococcus pyogenes and pseudomonas aeruginosa common in Kericho County. Plant leaves of the two plants were sourced from two sites (Bomet and Kabianga), dried, milled into powder and solvent extracted using hexane, dichloromethane: methanol ratio (1:1) and methanol. Phytochemicals present in each plant extract were evaluated using standard laboratory procedures. Antimicrobial sensitivity testing, Minimum Inhibitory Concentrations (MICs) and Minimum Bactericidal Concentration (MBC) were determined. Discs impregnated with standard antibacterial drugs were used as positive control. Leaves of T. alata and Senna didymobotrya collected from Bomet contained 7.41% and 10.4% while those from Kabianga contained 8.07% and 17.71% of extracts respectively, suggesting that site conditions do not influence the percentage of extracts. Leave extracts of S. didymobotrya and T. alata were found to be rich in alkaloids, flavonoids, terpenoids, glycosides and tannins irrespective of plant collection site, solvent of extraction. S. didymobotrya and T. alata plant extracts significantly inhibited growth of the exposed microbes in the following order: S. aureus, ≥S. pyogenes and≥ P. aeruginosa bacteria in comparison with commercial antibiotics (penicillin, chloromphenical, and erythromycin). The MIC values of the isolates ranged from 20×10-3 mg/ml to 4.8 ×10-3 mg/ml. However, bacterial inhibition by plant extracts showed re-growth of S. pyogenes after 36 hours, suggesting bacteriostatic nature. These results suggest that S. didymobotrya and T. alata leaves contain significant amounts of alkaloids, flavonoids, terpenoids, glycosides and tannins hence can be used as traditional medicine to manage S. aureus, S. pyogenes and P. aeruginosa bacteria found on human skin

Copper and nitrogen-doped carbon quantum dots as green nano-probes for fluorimetric determination of delafloxacin; characterization and applications

BackgroundCarbon quantum dots (CQDs) have gained much interest recently for being efficient probes. Their cost-effectiveness, eco-friendliness, and unique photocatalytic activities made them distinctive alternatives to other luminescent approaches like fluorescent dyes and luminous derivatization. Meanwhile, delafloxacin (DLF) is a recently approved antibacterial medicine. DLF has been authorized for the treatment of soft-tissue and skin infections as well as pneumonia. Therefore, new eco-friendly, cost-effective, and sensitive tools are needed its estimation in different matrices. ResultsIn the proposed study, green copper and nitrogen carbon dots (Cu-N@CDs) were synthesized from a green source (plum juice with copper sulphate). Cu-N@CQDs were then characterized using multiple tools including X-ray photon spectroscopy (XPS), FTIR and UV-VIS spectroscopy, Zeta potential measurements, High-resolution transmission electron microscopy (HRTEM), and fluorescence spectroscopy. After gradually adding DLF, the developed quantum dots’ fluorescence was significantly enhanced within the working range of 0.5–100.0 ng mL−1. The limits of detection and quantification were 0.08 and 0.27 ng mL−1, respectively. The accuracy of the proposed method ranged from 96.00 to 99.12 % in recovery%, when recovered from milk and plasma samples. SignificanceCu-N@CDs were utilized and validated for selectively determining DLF in several matrices including pharmaceutical forms, human plasma and in milk samples using spectrofluorimetric technique. The bio-analytical method is simple and could be used in content uniformity testing as well as in therapeutic drug monitoring in human plasma.

Assessment of De-Escalation of Empirical Antimicrobial Therapy in Medical Wards with Recognized Prevalence of Multi-Drug-Resistant Pathogens: A Multicenter Prospective Cohort Study in Non-ICU Patients with Microbiologically Documented Infection.

Antimicrobial resistance poses a major threat to human health worldwide and the implementation of antimicrobial stewardship programs (ASPs), including antimicrobial de-escalation (ADE), is a multifaceted tool for minimizing unnecessary or inappropriate antibiotic exposure. This was a prospective observational study of 142 non-Intensive Care Unit (ICU) patients with microbiologically documented infection who were initially administered empirical antimicrobial therapy and admitted to the medical wards of 6 tertiary-care hospitals in Greece from January 2017 to December 2018. Patients were divided into two groups, the ADE and non-ADE group, based on whether ADE was applied or not, respectively. Exploratory end-points were ADE feasibility, safety and efficacy. ADE was applied in 76 patients at a median time of 4 days (IQR: 3, 5). An increased likelihood of ADE was observed in patients with urinary tract (OR: 10.04, 95% CI: 2.91, 34.57; p < 0.001), skin and soft tissue (OR: 16.28, 95% CI: 1.68, 158.08; p = 0.016) and bloodstream infections (OR: 2.52, 95% CI: 1, 6.36; p = 0.05). Factors significantly associated with higher rates of ADE were clarithromycin administration, diagnosis of urinary tract infection (UTI), isolation of E. coli, age and symptoms type on admission. Mortality was lower in the ADE group (18.4% vs. 30.3% p < 0.1) and ADE was not significantly associated with the probability of death (p = 0.432). ADE was associated with favorable clinical outcomes and can be performed even in settings with high prevalence of multi-drug resistant (MDR) pathogens without compromising safety.

Is overweight a predictor for a more severe course of disease in cases of necrotizing fasciitis?

Necrotizing fasciitis is a rare but severe soft tissue infection, and its diagnosis is difficult and often delayed. Immediate treatment comprising extensive debridement, highly dosed broad-spectrum antibiotic therapy and intensive care is necessary to prevent fatal outcomes. Considering the global rise in overweight patients and the known negative effects of obesity on the immune system, the aim of this study was to analyze whether overweight results in a more severe course of necrotizing fasciitis, worse outcomes and an increased mortality rate among overweight patients compared than in normal weight patients. The present study involved a retrospective analysis of 29 patients who were treated for necrotizing fasciitis in our level one trauma center during the eight-year period between 2013 and 2020. Based on their BMIs, the patients were assigned to either the overweight group (BMI > 25) or the normal weight group. In the study population, being overweight appeared to be a predictor for a more severe course of necrotizing fasciitis. Overweight patients suffered from sepsis significantly more often than normal weight patients (13 vs. 5; p = 0.027). Furthermore, they were dependent on invasive ventilation (26.6 ± 33.8 vs. 5.9 ± 11.9 days; p = 0.046) as well as catecholamine support (18.4 ± 23.7 vs. 3.6 ± 5.7 days; p = 0.039) for significantly longer. Necrotizing fasciitis remains a challenging and potentially fatal disease. Within the patient collective, the severity of the disease and treatment effort were increased among overweight patients.

From Lab to Clinic: The Potential of Nanobubble Ozone Stored in Liposome with Pantothenic Acid (NOSLIP) in Treating Vaginal Infections with Long-lasting Effectiveness

Every year, 5-10 million women apply to various centers for sexually transmitted diseases due to infectious vaginitis (1). The three most notable causes of infectious vaginitis are bacterial vaginosis (BV), trichomoniasis, and vulvovaginal candidiasis (VVC). BV and VVC, which are endogenous genital infections, are the agents most responsible for the etiology of vaginal discharge (2). The most common symptoms of infectious vaginitis are vaginal discharge, itching, and a burning sensation. However, some cases are asymptomatic and are untreated (3). Group B streptococci (Streptococcus agalactiae; GBS) are gram-positive encapsulated bacteria that can colonize the intestinal and vaginal flora in 10-30% of healthy adults (4). Streptococcus agalactiae causes serious infections such as meningitis, sepsis, skin and soft tissue infections, pneumonia, urinary tract infections, and postpartum endometritis in newborns, pregnant women and adults with underlying diseases (4-6). Ozone is a highly reactive form of oxygen composed of three oxygen atoms. It is generated through the interaction of UV light and high-pressure diatomic oxygen. Ozone is widely acknowledged for its potent antibacterial properties due to its strong oxidative nature. Ozone therapy has garnered growing interest in recent years and is widely recognized for its beneficial impact on infection, reperfusion injury, cancer, and dental caries (7-8). At present, ozone therapy is an emerging approach in the clinical management of vaginitis. The medical ozone therapy device utilizes an ozone generator to produce a specific concentration of ozone, which is subsequently combined with filtered tap water to create ozonated water. Ozone and reactive chemicals exist in a liquid state and have a significant impact on vaginal sterilization (9).

A surge in the incidence of invasive Group A Streptococcus hand infections: a single Hand Unit experience.

We highlight an increase in the number of invasive Group A streptococcal soft tissue infections and present the impact of those on the hand surgery service, based on a single Hand Unit experience at the Pulvertaft Hand Centre.

Diagnosis, treatment and prognosis of Fournier’s gangrene in Africa: a scoping review protocol

Abstract Fournier’s gangrene is a rare necrotizing soft-tissue infection affecting the perineal, perianal and genital regions. It constitutes a genuine medical, surgical and urological emergency. Despite a better understanding of the etiology and pathophysiology of Fournier’s gangrene, mortality rates reported in the literature remain high. Still very common in Africa, it seems to occur mainly during hot, dry months and particularly affects people of low socio-economic status. This explains why the diagnosis is often made at a late stage. To our knowledge, there is no literature evaluating the epidemiology, clinical presentation, management and prognosis of Fournier’s gangrene in Africa, necessitating a review of the scope. This literature review protocol describes how the authors intend to study the available data on the presentation, management and prognosis of Fournier’s gangrene in Africa. Databases such as PubMed/Medline, Embase, Google Scholar and African Journal Online will be searched for articles published on Fournier’s gangrene in Africa and covering clinical, therapeutic and prognostic outcomes. The sociodemographic profile of all included studies will be examined. Results will include epidemiological, clinico-biological, severity score, management and prognostic data. Based on the analyzed results, the various parameters linked to the specific objectives of the African and non-African studies will be discussed and compared. This discussion will focus on clinical presentation, management and prognosis. This scoping review will be the first to address this research question, which has yet to be reported serially by African authors.

Pathogenomic profile and clonal diversity of potential zoonotic MRSA-CC7-ST789-t091-SCCmecV from human skin and soft tissue infections

The whole genome sequence (WGS) of prevalent MRSA strains harboring mecA gene obtained from skin and soft tissue infections (SSTIs) in Nigerian hospitals were profiled for pathogenomic structure and evaluated for clonal diversity. The two MRSA strains identified among 66 isolated multi-drug resistant S. aureus from a collection of 256 clinical samples were phenotyped for antibiotic resistance and genotyped for mecA, SCCmec, and spa types. The mecA positive MRSA was analysed using whole-genome sequencing for resistomes, virulomes, phylogenomic profiles and clonal diversity. The identified MRSA-CC7-ST789-t091-SCCmecV strains from a female child (aged 1 year) with severe otorrhea and an adult male (aged 23) with purulent wound abscess showed high-level resistance to streptomycin, vancomycin, kanamycin, sulfamethoxazole and ciprofloxacin. Both strains harbored abundant resistomes, inherent plasmids, chromosomal replicons and typical seven housekeeping genes (arc3, aroE4, glpF1, gmk4, pta4, tpi6, yqiL3). The most abundant putative virulomes were pathogenesis-associated proteins (included hemolysin gamma, leucocidins, proteases, staphylococcal superantigen/enterotoxin-like genes (Set/Ssl), capsule- and biofilm-associated genes, and hyaluronate lyase). Comparative phylogenomic analysis revealed the relatedness of the two clonal strains with prevalent MRSA-CC7 pathotypes observed in Italy (2013 and 2014), Denmark (2014), Thailand (2015 and 2016), USA (2018), and Nigeria (2016 and 2020); and share high genetic similarities with livestock strains from cow milk and cattle. Identified MRSA-CC7-ST789-t091-SCCmecV pathotypes implicated in SSTIs from Nigeria harboring repertoires of antibiotic resistance and virulence genes, and genetic relatedness with livestock strains; show the possibility of gene transfer between animal and human. Adequate hospital MRSA infection control and geno-epidemiological surveillance for animal and human transfer is required.

PLASMA CALPROTECTIN VERSUS CONVENTIONAL INFECTION BIOMARKERS IN HIP FRACTURE PATIENTS: A PROSPECTIVE COHORT STUDY

After a hip fracture, infections are common, but signs of infection resemble those of systemic inflammatory response to trauma and surgery, and conventional infection markers lack specificity. Plasma-calprotectin, a novel marker of neutrophil activation, has shown potential as an infection marker in ER and ICU settings.To investigate if plasma-calprotectin is superior compared to conventional infection biomarkers after hip fracture.Prospective cohort study of hip fracture patients admitted to our department. Calprotectin, procalcitonin (PCT), C-reactive protein (CRP), and white blood cell (WBC) count were measured in blood plasma upon admission and on day 3 post-surgery. Patients with infection (pneumonia, UTI, sepsis, SSI, other soft tissue infections) pre- or post-surgery were compared to a control group without infection within 30 days.Statistics: Wilcoxon rank-sum test, medians with interquartile range, and area under the curve (AUC) with 95% confidence intervals.Pilot study comprises calprotectin obtained at least once for 60 patients at admission and 48 on day 3. Mean age 84 years (SD 8.4), 65% women.9/60 patients (23%) were admitted with infections. They had higher levels of CRP (median 111 [73-149]) and PCT (0.35 [0.18–0.86]) compared to the control group (29 [16-64], p=0.037; 0.10 [0.07–0.17], p=0.007). Calprotectin (2.67 vs 2.51) and WBC (12.2 vs 9.3) did not differ significantly. AUC was highest for PCT (0.79 [CI 0.60–0.97]), followed by CRP (0.71 [0.46–0.96]), WBC (0.60 [0.35–0.84]), and calprotectin (0.58, [0.33–0.83]).Day 3, 6/48 (13%) had infections, without significant differences between groups in any marker. The median levels were: calprotectin 3.5 vs 3.1, CRP 172 vs 104, WBC 12 vs 9, PCT 0.16 vs 0.17. Calprotectin had highest AUC 0.68 (0.41–0.93, n.s.). AUC for WBC was 0.67 (0.31–1.00), CRP 0.66 (0.38–0.94), PCT 0.56 (0.29–0.82).Preliminary data show no significant associations with postoperative infection for any of the studied biomarkers. However, plasma-calprotectin might perform slightly better compared to conventional markers.

Comparative analysis of healthcare resource utilization: necrotizing soft tissue infections versus burn injuries

Comparative analysis of healthcare resource utilization: necrotizing soft tissue infections versus burn injuries

Isolation of Staphylococcus pseudintermedius in Immunocompromised Patients from a Single Center in Spain: A Zoonotic Pathogen from Companion Animals.

Staphylococcus pseudintermedius, a commensal opportunistic bacterium predominantly residing in the skin of companion animals, particularly dogs, has the potential to induce skin and soft tissue infections in pets, and zoonotic infections, including catheter-related complications. This study documents four cases of S. pseudintermedius infection or colonization in patients who had close contact with dogs or cats. Identification of the bacterial species was performed using MALDI-TOF mass spectrometry, and antibiotic susceptibility was determined using microdilution assay. DNA was sequenced using Nanopore technology followed by in silico analysis. Three isolates were multidrug resistant, including resistance to methicillin, with one belonging to the prevalent European lineage ST551, and the other two were attributed to a novel multilocus sequence type, ST2672. The remaining isolate was attributed to the novel multilocus sequence type ST2673 and was methicillin susceptible. All four isolates exhibited an array of virulence factors that contributed to colonization, damage to host immune cells, and biofilm formation. All the ST551 isolates included in the comparative analysis displayed clonality within the European continent. The importance of describing zoonotic infections associated with S. pseudintermedius resides in the scarcity of available scientific literature, further accentuated by its heightened resistance profile and potential complications, particularly in the context of catheter-related infections.

Antimicrobial activity of apricot kernel extract loaded carboxymethyl chitosan nanoparticles against multidrug resistant wound-skin infection bacteria

In recent years, skin and soft-tissue infections, particularly due to multidrug resistance bacteria (MDR) are generating a serious health crisis to human health. Thus, the current investigation tried to find new promising alternatives such as herbal therapy and biopolymer nanotechnology to combat MDR microbes. Apricot kernels extract was prepared and its amygdalin content was determined by HPLC analysis. Carboxymethyl chitosan nanoparticles (CMC NPs) encapsulated with amygdalin extract (Am ext) were synthesized and characterized through their morphology, particle size, zeta potential and thermal analysis. The antibacterial activity of Am ext, CMC NPs and CMC-Am ext NPs were evaluated against MDR bacteria. Moreover, to confirm the antibacterial action of the samples, bacterial DNA fragmentation analysis was performed. Furthermore, the cyanide ions released from bacterial breakdown of amygdalin was confirmed using Nanocolor Cyanide 08 Test 0–31 kits. The HPLC analysis indicated that amygdalin extracted efficiently from the apricot kernels. The CMC-Am ext NPs exhibited spherical shaped and mono dispersed particles of size 28 nm; physical stability and thermal compatibility. Additionally, CMC-Am ext NPs have significant antibacterial action on all MDR microbes in synergy with Am ext. Moreover, the results confirmed that the cyanide ions were released from amygdalin breakdown by the action of bacteria. Furthermore, the DNA fragmentation analysis confirmed that both Am ext and its nano-encapsulated form caused bacterial cell death by inducing DNA damage. Therefore, these findings demonstrate CMC-Am ext NPs as a novel potential therapeutic agent which can be used as an alternative to the current antibiotics against MDR bacteria.

Drug use practices and wound care experiences in the age of xylazine adulteration

Exposure to xylazine has been associated with wounds distinct from typical injection-related skin and soft tissue infections. We sought to understand drug use and wound care practices, and treatment experiences of people who use drugs (PWUD) in a high-prevalence area of xylazine adulteration. In August 2023, we surveyed adult PWUD reporting at least one past-year drug use-related wound across three Massachusetts syringe service programs. Using a representative illustration, participants indicated if they had experienced a xylazine wound in the past 90 days. We compared demographic, drug use factors, wound care, and medical treatment experiences among those with and without xylazine wounds. We also conducted additional content analysis of open-ended responses. Of the 171 respondents, 87 % (n=148) had a xylazine wound in the past 90 days. There were no statistically significant demographic differences between those with and without xylazine wounds. Among those primarily injecting (n=155), subcutaneous injection was nearly ten times more likely among people with xylazine wounds. For those with xylazine wounds (n=148), many engaged in heterogeneous wound self-treatment practices, and when seeking medical care, 74 % experienced healthcare stigma and 58 % had inadequate pain and withdrawal management. People with self-identified xylazine wounds were more likely to engage in subcutaneous injection and faced several barriers seeking medical wound treatment. Programs serving people exposed to xylazine should work to support safer injection practices, including alternatives to injecting and improving access to high-quality, effective wound care. Further study is warranted to understand the causes, promoters, and prevention of xylazine-related wounds.

Infections after musculoskeletal injuries in earthquake survivors.

This study aimed to investigate the infections following musculoskeletal injuries in earthquake survivors, offering a future clinical point of reference for the handling of musculoskeletal injuries resulting from earthquakes. In this single-center retrospective observational study, 225 earthquake survivors (120 females, 105 males; median: 39 years; range, 18 to 94 years) admitted between February 2023 and April 2023 were evaluated. Patients with musculoskeletal injuries and patients who had at least one month of follow-up data were included in the study. Diagnosis of healthcare-associated infections was verified by an infection control physician in accordance with the Centers for Disease Control and Prevention. Among all cultures, the most isolated pathogen was Acinetobacter baumannii (49.4%), followed by enterococci (28.6%). Colistin sensitivity of A. baumannii was 36 (94.7%). However, sensitivity rate was 5.3% for ciprofloxacin, 10.5% for piperacillin-tazobactam, and 26.4% for carbapenems, which are frequently used for skin and soft tissue infections. Among all, 76% of the microorganisms isolated from wound culture and 58% of the microorganisms isolated from deep tissue culture were found to be multidrug-resistant pathogens. During the follow-up, 12 (5.3%) patients had hospital-acquired urinary tract infections, 13 (5.7%) patients had hospitalacquired bloodstream infections, one (0.4%) patient had hospital-acquired pneumonia, and 74 (32.8%) patients had surgical site infections. Eighty (35.6%) of the patients were followed up in the intensive care unit, and the overall mortality rate was 2.7%. While gram-positive microorganisms are frequently the causative microorganisms in infections after traumatic injuries, this study revealed that gram-negative microorganisms could be observed more frequently in postearthquake traumatic injuries. Most causative microorganisms are resistant to commonly prescribed antibiotics in clinical settings, which makes them more challenging to treat.

A Comprehensive Analysis of Liposomal-Based Nanocarriers for Treating Skin and Soft Tissue Infection.

Bacterial skin and soft tissue infections (SSTIs) are widespread microbic invasions of the skin and deeper tissues. Topical drug delivery systems are the most favored administration pathway when treating SSTIs. This is down to their minimal risk of inducing systemic adverse events, reduced development of bacterial resistance, and ease of application. However, they have several drawbacks, including the lack of control over the drug release profile, skin irritations, and the limited permeability of certain compounds through the skin. To address these limitations, several nanocarrier systems were developed, with nanoliposomes standing out as the leading delivery system for the topical management of SSTIs. Despite considerable research into liposomes over the past decade, there remains a gap in detailed knowledge about designing these carriers specifically for SSTIs. Consequently, there is a pressing need for comprehensive research that focuses on the use of nanoliposomes for SSTIs and offers an extensive understanding of both SSTIs and liposomal formulations. This review explores bacterial SSTIs, covering their epidemiology, classification, microbiology, and management. It emphasizes the contribution of liposome-based nanovesicles in enhancing the local administration of antibiotics and natural antibacterial compounds for SSTI management. It also delves into the effects of liposomal formulation changes on the disease therapeutic outcomes. Additionally, it provides a guide for aligning the characteristics of the liposomes with the infection types, depths, properties, and causative agents. This signifies a substantial leap forward in the domains of drug design, development, and delivery.

Necrotizing soft tissue infections

Necrotizing soft tissue infections are aheterogeneous group of severe infections of the skin, connective tissue and muscles in which necrotic destruction of the tissue occurs at the site of infection. Various bacteria are known as "typical" triggering pathogens and the infection can occur on the entire surface of the body. Necrotizing soft tissue infections are always atime-sensitive emergency associated with high mortality. Many affected patients are critically ill and require treatment in an intensive care unit. The rapid and radical surgical treatment is an essential part of management and in addition an adequate and timely antimicrobial treatment is of great importance. The health consequences for surviving patients are often severe, as extensive soft tissue damage leads to functional impairments. In many cases extensive plastic surgery follow-up is necessary. Therefore, necrotizing soft tissue infections are "complicated" in every phase of the disease and require interprofessional treatment. This review article provides a current overview of various aspects of the diagnostics, treatment and aftercare of necrotizing soft tissue infections.

In vitro activity of delafloxacin against clinical levofloxacin-resistant Helicobacter pylori isolates.

Increasing antibiotic resistance in Helicobacter pylori necessitates research on new active molecules. In 2017, delafloxacin, a new fluoroquinolone with chemical properties of activity under acidic conditions, was approved for treatment of community-acquired bacterial pneumonia and acute bacterial skin and soft-tissue infections. Mutations in gyrA are responsible for fluoroquinolone resistance, but certain clinical isolates of H. pylori appear to display a dual phenotype: resistance to levofloxacin associated with very low delafloxacin MICs. To estimate epidemiological cut-off (ECOFF) values and to identify mutations in the gyrA gene, specific to FQ resistance, without increasing the MICs of delafloxacin. Clinical strains (n = 231) were collected in the bacteriology laboratory of Poitiers University Hospital over a 2 year period to determine the ECOFF of delafloxacin. Retrospectively, 101 clinical strains with an levofloxacin-resistant phenotype (MIC > 1 mg/L) were selected from 2018 to 2022 for delafloxacin MIC determination and QRDR (gyrA) sequencing. The estimated ECOFF of delafloxacin was ≤0.125 mg/L. No H. pylori isolate showed a levofloxacin-sensitive phenotype with a delafloxacin MIC of >0.125 mg/L. Among the levofloxacin-resistant H. pylori isolates, 53.5% had delafloxacin MICs of ≤0.125 mg/L. The N87I mutation was associated with dual levofloxacin/delafloxacin resistance (P < 0.001) in contrast to the N87K and D91N mutations (P > 0.05). Mutations D91G and D91Y were not associated with a delafloxacin resistance phenotype (P > 0.05). Delafloxacin seems to be a therapeutic alternative for levofloxacin-resistant strains with greater in vitro activity. However, further clinical/biological investigations are required to determine its efficacy in H. pylori eradication.

The Impact of a Methicillin-Resistant Staphylococcus Aureus Nasal Polymerase Chain Reaction Protocol on Vancomycin Length of Therapy Among Patients With Skin and Soft Tissue Infections.

Objective: We evaluated the impact of a methicillin-resistant Staphylococcus aureus (MRSA) nasal polymerase chain reaction (PCR) protocol on the vancomycin length of therapy (LOT) for skin and soft tissue infections (SSTIs). Design: Retrospective quasi-experimental pre- and post- MRSA nasal PCR protocol implementation study. Setting: Tertiary-care academic medical center in Jacksonville, Florida. Patients: Eligible patients received empiric vancomycin for SSTIs from January 1st to September 30th 2020 (pre-implementation group) and from January 1st to September 30th 2022 (post-implementation group). Intervention: The electronic health system software was modified to provide a best-practice advisory (BPA) prompt to the pharmacist upon order verification of vancomycin for patients with SSTIs. Methods: We reviewed patient records to determine the time from vancomycin prescription to de-escalation. The secondary outcomes were incidence of acute kidney injury (AKI), number of vancomycin levels collected, and hospital length of stay (LOS). Results: The study included 131 patients (pre-implementation, n = 86 and post-implementation, n = 45). There was no significant difference in vancomycin length of therapy (LOT) between implementation groups: mean LOT in days and standard deviation (SD) were 2.7 (1.9) and 2.6 (1.3), respectively, p-value 0.493. Of significance, in the post-implementation group, vancomycin LOT between patients with a negative and positive MRSA PCR were 2.3 (1.1) and 3.9 (1.6), p-value 0.006. There was no difference in secondary outcomes. Conclusion: The utilization of the MRSA nasal PCR to guide vancomycin de-escalation did not significantly change the vancomycin LOT, however in the post-implementation group there was a significant difference in vancomycin LOT between negative and positive MRSA PCRs.

Antimicrobial Peptide-Based Sensor for the Electrochemical Detection of Methicillin-Resistant Staphylococcus Aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a gram-positive bacterium that colonizes on the skin and nasal track of humans, which can lead to serious illnesses such as skin and soft tissue infections, pneumonia, and septicemia.MRSA is resistant to an entire class of antibiotics called beta-lactams, including penicillin, amoxicillin, and oxacillin, making it more difficult to treat. Culture based methods and molecular based methods like PCR are currently being used for the detection of MRSA, but these methods possess the drawbacks of being slow and expensive, respectively. Thus, we focused on developing a reagentless, cost-effective, near real-time detection method for intact MRSA cells.Antimicrobial peptides (AMPs) possess the ability to interact with bacterial cells by inhibiting their growth or by lysing them.However, this initial interaction between the cationic AMPs and the negatively charged bacterial cells can be used for the detection of pathogens like MRSA. Here, we used a MRSA-specific antimicrobial peptide, DP7, to fabricate an electrochemical peptide-based (E-PB) sensor. The DP7 probe was further modified with a methylene blue redox label and an alkanethiol chain which allows for the formation of a thiol-gold self-assembled monolayer. The sensor surface was passivated with both 6-mercapto-1-hexanol and a thiolated tetra-thymine sequence to prevent surface fouling. Electrochemical detection of MRSA was accomplished using alternating current voltammetry. Control experiments were performed using two gram-positive bacteria, Bacillus subtilis and Staphylococcus epidermidis, and two gram-negative bacteria, Escherichia coli and Pseudomonas aeruginosa. The DP7 sensor responded to MRSA in a concentration-dependent manner and was proven to be selective for MRSA over the other four microbes. Specifically, the % signal suppression obtained for MRSA was much larger when compared to those obtained for the other microbes. The same behavior was observed in pure buffer and 5% synthetic wound fluid. In addition, the detection time was relatively short, with signal saturation in less than 60 min. Overall, the DP7 sensor has demonstrated to possess attributes similar to other E-PB sensors. It has the potential to be developed as a rapid, reliable, and cost-effective diagnostic tool for MRSA, which will be useful in preventing the spread of the pathogen in the community. Furthermore, this sensing platform is versatile and can be redesigned for detection of other pathogenic bacteria.