Risk factors associated with methicillin-resistant Staphylococcus aureus skin and soft tissue infections in hospitalized patients in Colombia

An injectable and light curable hyaluronic acid composite gel with anti-biofilm, anti-inflammatory and pro-healing characteristics for accelerating infected wound healing

Bacterial biofilm formation and drug resistance are common issues associated with wound healing. Antimicrobial peptides (AMPs) are a new class of antimicrobial agents with the potential to solve these global health issues. New injectable adhesive antibacterial hydrogels have excellent prospects of becoming the next innovative wound-healing dressings. In this study, the hyaluronic acid was connected to the antibacterial peptide Plantaricin 149 (Pln149), obtaining HAD@AMP. HAD@AMP performed well in efficient antimicrobial activity, good histocompatibility, low drug resistance, low bacterial biofilm formation, and fast wound healing process which are essential for rapid healing of infected wound. During the hydrogel degradation process, Pln149 was released to inhibit bacterial communication and reduce bacterial biofilm formation. Meanwhile, HAD@AMP could up-regulate anti-inflammatory and pro-angiogenic factors, and down-regulate inflammatory factors to promote the healing of infected wounds, which provide a new idea for skin healing strategies.

In Vitro Activity of Ceftaroline and Comparators against Bacterial Isolates Collected Globally from Patients with Skin and Soft Tissue Infections: ATLAS Program 2019-2020

The objective of this study was to assess the in vitro activity of ceftaroline and a panel of comparator agents against isolates causing skin and soft tissue infections (SSTIs) collected in Africa/Middle East, Asia-Pacific, Europe, and Latin America from 2019-2020. Minimum inhibitory concentrations (MIC) were determined using European Committee on Antimicrobial Susceptibility Testing criteria. All the methicillin-susceptible Staphylococcus aureus (MSSA) isolates were susceptible to ceftaroline. Across all regions, ceftaroline demonstrated potent activity against methicillin-resistant S. aureus (MRSA, susceptibility 89.5-93.7%) isolates. Susceptibility to vancomycin, daptomycin, linezolid, teicoplanin, trimethoprim sulfamethoxazole, and tigecycline was ≥94.1% in MSSA and MRSA isolates. Against β-hemolytic streptococci isolates, ceftaroline demonstrated very potent activity (MIC90 0.008-0.03 mg/L) across all regions. All β-hemolytic streptococci isolates were susceptible to linezolid, penicillin, and vancomycin (MIC90 0.06-2 mg/L). Among the extended-spectrum β-lactamases (ESBL)-negative Enterobacterales tested (E. coli, K. pneumoniae, and K. oxytoca), susceptibility to ceftaroline was high (88.2-98.6%) in all regions. All ESBL-negative Enterobacterales were susceptible to aztreonam. Potent activity was observed for amikacin, cefepime, and meropenem (94.1-100%) against these isolates. Overall, ceftaroline showed potent in vitro activity against isolates of pathogens causing SSTIs. Continuous surveillance of global and regional susceptibility patterns is needed to guide appropriate treatment options against these pathogens.

Antibiotic Management of Uncomplicated Skin and Soft Tissue Infections in the Real World

Background: Skin and soft tissue infections are one of the main causes of consultations worldwide. The objective was to determine the treatment of a group of patients with uncomplicated skin and soft tissue infections in Colombia. Methods: Follow-up study of a cohort of patients with skin infections who were treated in the Colombian Health System. Sociodemographic, clinical and pharmacological variables were identified. Treatments were evaluated using clinical practice guidelines for skin infections. Results: A total of 400 patients were analyzed. They had a median age of 38.0 years and 52.3% were men. The most commonly used antibiotics were cephalexin (39.0%), dicloxacillin (28.0%) and clindamycin (18.0%). A total of 49.8% of the subjects received inappropriate antibiotics, especially those with purulent infections (82.0%). Being cared for in an outpatient clinic (OR: 2.09; 95% CI: 1.06-4.12), presenting pain (OR: 3.72; 95% CI: 1.41-9.78) and having a purulent infection (OR: 25.71; 95% CI: 14.52-45.52) were associated with a higher probability of receiving inappropriate antibiotics. Conclusions: Half of patients with uncomplicated skin and soft tissue infections were treated with antibiotics that were not recommended by clinical practice guidelines. This inappropriate use of antibiotics occurred in the vast majority of patients with purulent infections because the antimicrobials used had no effect on methicillin-resistant Staphylococcus aureus.

Efficacy of Vaporized Hydrogen Peroxide Combined with Silver Ions against Multidrug-Resistant Gram-Negative and Gram-Positive Clinical Isolates

Antimicrobial resistance (AMR) is a serious public health problem that results in high morbidity and mortality rates. In particular, multidrug-resistant (MDR) strains circulating in hospital settings pose a major threat as they are associated with serious nosocomial infections. Therefore, regular cleaning and disinfection procedures, usually using chemical disinfectants, must be implemented in these facilities. Hydrogen peroxide (HP)-based disinfectants have proven high microbicidal activity and several comparative advantages over conventional disinfectants. We assessed the in vitro biocidal activity of an 8% HP solution combined with 30 mg/L silver ions (HP + Ag) against MDR clinical isolates of Klebsiella pneumoniae (MDRKp) and Pseudomonas aeruginosa (MDRPa), and methicillin-resistant Staphylococcus aureus (MRSA). Accordingly, the in vitro antibacterial activity was determined using the macrodilution method, and the efficacy was determined for 30 min in terms of (1) activity on bacteria in suspension and (2) activity on surfaces using vaporized HP + Ag on a 20 cm2 stainless steel surface. A strong bactericidal effect of HP + Ag was observed against MDRKp, MDRPa, and MRSA strains, with minimum inhibitory concentrations and minimum bactericidal concentrations between 362.5 and 5800 mg/L. A strong effect was observed during the 30 min of HP + Ag exposure to the resistant clinical isolates, with over 4-Log10 reduction in CFUs. Regarding the efficacy of the disinfectant on surfaces, bacterial load reductions of >99% were observed. These results suggest that HP + Ag is potentially useful as an effective disinfectant for decontaminating surfaces in hospital settings suspected of contamination with MDR bacteria.

Multifunctional polyethylene imine hybrids decorated by silica bioactive glass with enhanced mechanical properties, antibacterial, and osteogenesis for bone repair

Inorganic/organic hybrids and bioactive glasses demonstrate promising potential as bone substitute biomaterials. A sol-gel hybrid consisting of silica bioactive glass and biodegradable polymer can combine the high bioactivity of a glass with the toughness of a polymer. In this study, multifunctional hybrids with a combination of organic-inorganic hybrid structure class II consisting of polyethyleneimine (PEI) generation 4 (G4) and bioactive glass with enhanced mechanical properties, mineralization, antibacterial, and osteogenesis activities were synthesized by the sol-gel method. Glycidoxypropyl) trimethoxysilane (GPTMS) with different concentrations was used as a covalent bonding agent between PEI polymer and bioactive glass. The effect of GPTMS content was assessed in the presence and absence of calcium in the hybrid structures in terms of morphology, wettability, mechanical properties, antibacterial activity, cell viability, and in vitro osteogenic differentiation properties. By increasing the amount of GPTMS, the compressive strength increased from 1.95 MPa to 2.34 MPa, which was comparable to human trabecular bone. All the hybrids presented antibacterial activity against Staphylococcus aureus, forming an inhibition zone of 13-16 mm. An increase in cell viability of 82.22% in PSCaG90 was obtained after 1 day of MG-63 cell culture. Alkaline phosphatase expression and mineralization of MG-63 cells increased in the PSCaG90 hybrid in the absence of an osteogenic medium compared to PSG60 and PSG90. The PSCaG90 hybrid indicated considerable in vitro osteogenic capacity in the absence of a differentiation medium, expressing high levels of bone-specific proteins including collagen I (COL1A1), Runt-related transcription factor 2 (RUNX2), osteopontin (OPN), and osteocalcin (OCN), compared to calcium-free hybrids. Overall, our results suggest that the presence of calcium in the PSCaG90 leads to a significant increase in osteogenic differentiation of MG-63 cells even in the absence of differentiation medium, which suggests these hybrid structures with multifunctional properties as promising candidates for bone repair.

Community-genotype methicillin-resistant Staphylococcus aureus skin and soft tissue infections in Latin America: a systematic review

Background

Community-genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) emerged in the 1990s as a global community pathogen primarily involved in skin and soft tissue infections (SSTIs) and pneumonia. To date, the CG-MRSA SSTI burden in Latin America (LA) has not been assessed.

Objective

The main objective of this study was to report the rate and genotypes of community-genotype methicillin-resistant Staphylococcus aureus (CG-MRSA) causing community-onset skin and soft tissue infections (CO-SSTIs) in LA over the last two decades. In addition, this research determined relevant data related to SSTIs due to CG-MRSA, including risk factors, other invasive diseases, and mortality.

Data sources

Relevant literature was searched and extracted from five major databases: Embase, PubMed, LILACS, SciELO, and Web of Science.

Methods

A systematic review was performed, and a narrative review was constructed.

Results

An analysis of 11 studies identified epidemiological data across LA, with Argentina presenting the highest percentage of SSTIs caused by CG-MRSA (88%). Other countries had rates of CG-MRSA infection ranging from 0 to 51%. Brazil had one of the lowest rates of CG-MRSA SSTI (4.5–25%). In Argentina, being younger than 50 years of age and having purulent lesions were predictive factors for CG-MRSA CO-SSTIs. In addition, the predominant genetic lineages in LA belonged to sequence types 8, 30, and 5 (ST8, ST30, and ST5).

Conclusion

There are significant regional differences in the rates of CG-MRSA causing CO-SSTIs. It is not possible to conclude whether or not CG-MRSA CO-SSTIs resulted in more severe SSTI presentations or in a higher mortality rate.

Drug resistance of pathogens causing nosocomial infection in orthopedics from 2012 to 2017: a 6-year retrospective study

Background

Hospital-acquired infections (HAIs) are an emerging global problem that increases in-hospital mortality, length of stay, and cost. We performed a 6-year retrospective study to provide valuable insight into appropriate antibiotic use in HAI cases. We also aimed to understand how hospitals could reduce pathogen drug resistance in a population that overuses antibiotics.

Methods

All data (2012–2017) were obtained from the hospital information warehouse and clinical microbiology laboratory.

Results

We isolated 1392 pathogen strains from patients admitted to the orthopedics department during 2012–2017. Escherichia coli (14.7%, 204/1392), Enterobacter cloacae (13.9%, 193/1392), and Staphylococcus aureus (11.3%, 157/1392) were the most common pathogens causing nosocomial infections. The dominant Gram-negative bacterium was E. coli, with high resistance to ampicillin, levofloxacin, cotrimoxazole, gentamicin, and ciprofloxacin, in that order. E. coli was least resistant to amikacin, cefoperazone-sulbactam. The most dominant Gram-positive bacterium was S. aureus, highly resistant to penicillin and ampicillin, but not resistant to fluoroquinolones and cotrimoxazole. Analysis of risk factors related to multidrug-resistant bacteria showed that patients with open fractures (Gustillo III B and IIIC) were significantly more susceptible to methicillin-resistant S. aureus infections (p < 0.05). Additionally, extended-spectrum β-lactamase-producing E. coli infections occurred significantly more often in patients with degenerative diseases (p < 0.05). Elderly patients tended to be more susceptible to multidrug-resistant bacterial infections, but this outcome was not statistically significant.

Conclusions

Antimicrobial resistance is a serious problem in orthopedics. To effectively control antimicrobial resistance among pathogens, we advocate extensive and dynamic monitoring of MDR bacteria, coupled with careful use of antibiotics.

Sex differences in hospitalized adult patients with cellulitis: A prospective, multicenter study

OBJECTIVES

Sex differences in adult cellulitis, a frequent cause of hospitalization, have not been analyzed. These differences were investigated in a large cellulitis series.

METHODS

This was a prospective observational study of 606 Spanish hospitalized cellulitis patients. Different comorbidities, clinical, diagnostic, and treatment data were compared between the sexes. Multiple logistic regression modeling was performed to determine the variables independently associated with sex.

RESULTS

Overall 606 adult cellulitis patients were enrolled; 314 (51.8%) were male and 292 (48.2%) were female. Females were older (mean age 68.8 vs 58.9 years, p < 0.0001), less likely to have prior wounds (p = 0.02), and more likely to have venous insufficiency (p = 0.0002) and edema/lymphedema (p = 0.0003) than males. The location of the infection differed between the sexes (p = 0.02). Males were more likely to have positive pus cultures (p = 0.0008), the causing agent identified (p = 0.04), and higher rates of Staphylococcus aureus infection (p = 0.04) and received longer antibiotic treatment (p = 0.03). Factors independently associated with female sex in the multivariate analysis were older age (p < 0.0001), prior cellulitis (p = 0.01), presence of edema/lymphedema as the predisposing factor (p = 0.004), negative versus positive pus culture (p = 0.0002), and location of cellulitis other than in the lower extremities (p = 0.035).

CONCLUSIONS

Differences between male and female patients with cellulitis were age, recurrence, presence of edema/lymphedema, positivity of pus culture, and topography of the infection.

Staphylococcus aureus Nasal Colonization in Spanish Children. The COSACO Nationwide Surveillance Study

Objective

To assess the prevalence and risk factors for S. aureus and methicillin-resistant S. aureus (MRSA) nasal colonization in Spanish children.

Methods

Cross-sectional study of patients <14 years from primary care centers all over Spain. Clinical data and nasal aspirates were collected from March to July 2018.

Results

A total of 1876 patients were enrolled. Prevalence of S. aureus and MRSA colonization were 33% (95% CI 30.9–35.1) and 1.44% (95% CI 0.9–2), respectively. Thirty-three percent of the children (633/1876) presented chronic conditions, mainly atopic dermatitis, asthma and/or allergy (524/633). Factors associated with S. aureus colonization were age ≥5 years (OR 1.10, 95% CI 1.07–1.12), male sex (OR 1.43, 95% CI 1.17–1.76), urban setting (OR 1.46, 95% CI 1.08–1.97) and the presence of asthma, atopic dermatitis or allergies (OR 1.25; 95% CI: 1.093–1.43). Rural residence was the only factor associated with MRSA colonization (OR 3.62, 95% CI 1.57–8.36). MRSA was more frequently resistant than methicillin-susceptible S. aureus to ciprofloxacin [41.2% vs 2.6%; p<0.0001], clindamycin [26% vs 16.9%; p=0.39], and mupirocin [14.3% vs 6.7%; p=0.18]. None of the MRSA strains was resistant to tetracycline, fosfomycin, vancomycin or daptomycin.

Conclusions

The main risk factors for S. aureus colonization in Spanish children are being above five years of age, male gender, atopic dermatitis, asthma or allergy, and residence in urban areas. MRSA colonization is low, but higher than in other European countries and is associated with rural settings.

Phylogeny of hospital acquired MRSA, and its comparative phenotypic clinico-epidemiology with vancomycin resistant S. aureus (VRSA)

Staphylococcus aureus is emerging as complicated pathogen because of its wide-ranging origin, multiple variants, and compromised antibiotic susceptibilities. Current study was planned to find lineage of hospital acquired methicillin resistant Staphylococcus aureus (HA-MRSA), and its comparative phenotypic clinico-epidemiology with vancomycin resistant S. aureus (VRSA). A total of (n = 200) samples were aseptically collected from wound, nose, and cerebrospinal fluid of patients from metropolitan and rural background hospitals along with on spot filling in of questionnaire. Phylogenetic analysis of HA-MRSA was identified by targeting mecA gene in S. aureus. At optimal tree branch length of 1.91 and evolutionary distance 0.1, high level sequence similarity (97%-99%) was observed with different strains of S. aureus isolated from both human and animal. Non-descriptive statistics at 5% probability found 61% S. aureus, while 43.44% of them were HA-MRSA, 92.62% VRSA, and 42.62% were both MRSA and VRSA. Among assumed risk factors, use of antibiotics, venous catheterization, chronic disease, pre-hospital visits, and ICU admitted patients showed significant association (p<0.05) with pathogen. HA-MRSA was 37.50%, 80%, and 37.50% sensitive to chloramphenicol, gentamicin, and oxacillin, respectively. While <50% of VRSA were sensitive against oxacillin, enoxacin, and chloramphenicol. A significant difference (p<0.05) of percentage responses of MRSA and VRSA at resistant, intermediate, and sensitive cadre against all antibiotics except chloramphenicol was obvious in this study. The Current study concluded higher prevalence of MRSA & VRSA, significant association of risk factors, limiting antibiotic susceptibility profile, and genetic transfer at animal-human interface which suggests further studies cum preventive strategies to be planned.

Diagnosis and Treatment of Lip Infections

PURPOSE

Staphylococcus aureus is a gram-positive, facultative anaerobic, cocci bacterium that naturally colonizes the skin. S aureus can cause a mild to severe infection depending on the location, depth of invasion, and immune status. Guidelines regarding treatment of patients with lip infections are scant. The purpose of this study was to present the diagnosis, management, and outcome of a cohort of patients with lip infections caused by S aureus.

MATERIALS AND METHODS

This was a retrospective cohort study of patients with a lip infection caused by S aureus treated by Emory Oral and Maxillofacial Surgery Service (Atlanta, GA). Predictor variables were patient demographic characteristics, clinical presentation, laboratory findings, imaging characteristics, intervention, and length of stay. The outcome variable was infection resolution or persistence. Data were collected using a standardized collection form. Descriptive statistics were computed.

RESULTS

Seven patients (mean age, 38 years) with lip swelling met the inclusion criteria. The patients did not undergo recent hospitalization and/or recent surgery. Patients had immunodeficiency virus or other medical comorbidities. Radiographic findings were consistent with abscess formation. Management consisted of antibiotics only or surgical intervention with antibiotics. Lip cultures showed S aureus with methicillin-sensitive or -resistant S aureus. Treatment was intravenous followed by oral antibiotics. The average length of inpatient stay was 4 days. There were no postoperative complications. All lip infections achieved complete clinical resolution.

CONCLUSIONS

In this cohort, treatment of lip swelling caused by S aureus required surgical intervention and/or antibiotics. Immune compromise and antibiotic resistance should be considered in a patient with a similar presentation.