Skin Tissue Infections Research Articles

Population Pharmacokinetics of Tigecycline for Critically Ill Patients Undergoing Continuous Renal Replacement Therapy.

Tigecycline is considered one of the last resorts for treating infections caused by multidrug-resistant bacteria. Continuous renal replacement therapy (CRRT) is widely used in critically ill patients, especially those with acute kidney injury or severe infections. However, pharmacokinetic data for tigecycline in patients receiving CRRT are limited. This was a single-center prospective clinical study with intensive sampling that included critically ill patients who received tigecycline and CRRT. A population pharmacokinetic (PPK) model was developed and evaluated by goodness-of-fit plots, bootstrap analysis, visual predictive checks, and numerical predictive checks. Pharmacokinetic/pharmacodynamic target attainment and cumulative fraction of response analyses were performed to explore the potential need for dose adjustments of tigecycline in CRRT. In total, 21 patients with 167 concentrations were included. A two-compartment model adequately described the tigecycline concentration-time points, but no covariates were found to adequately explain the viability in the pharmacokinetic parameters of tigecycline. The typical values of CL, Q, V1 and V2 were 4.42 L/h, 34.8 L/h, 30.9 L and 98.7 L, respectively. For most infections, the standard regimen of 50 mg/12h was deemed appropriate, expect for skin and soft skin tissue infections and community-acquired pneumonia caused by Acinetobacter baumannii and Klebsiella pneumoniae, which required a dosage regimen of 100 mg/12h or higher. A tigecycline PPK model describing critically ill patients undergoing CRRT was successfully developed. The optimized dosage regimens for various infections are recommended.

1754. Implementation of a targeted antimicrobial stewardship clinical decision support system on outpatient fluoroquinolone prescribing

Abstract Background Fluoroquinolones are broad spectrum antibiotics with several Food and Drug Administration (FDA)-issued black box warnings. Due to these risks, the FDA recommends reserving fluoroquinolones for situations with no alternatives. Beginning in 2020, the Joint Commission required outpatient antimicrobial stewardship activities due to overprescribing and growing resistance to antimicrobials. The role of this study was to implement a clinical decision support system (CDSS) targeting inappropriate outpatient fluoroquinolone prescribing. Methods This was a single center, quasi-experimental study evaluating patients prescribed oral fluoroquinolones in an outpatient ambulatory care setting between December 1, 2020-February 28, 2021 and December 1, 2021-February 28, 2022. Patients included in this study were divided into Pre-CDSS and Post-CDSS groups if they received oral antibiotics for pre-determined indications (see table 2 for the list of indications). The primary outcome was overall reduction in outpatient fluoroquinolone prescribing. Secondary objectives were reduction in outpatient fluoroquinolone prescribing by indication, orders by provider type, appropriate fluoroquinolone dosing per renal function and incidence of an emergency department (ED) visit or hospitalization within 90 days consistent with a fluoroquinolone adverse drug reaction. Results A total of 2,447 (1,105 in Pre-CDSS vs. 1,342 in Post-CDSS) were included for analysis. Fluoroquinolone prescribing significantly decreased in Post-CDSS group compared to Pre-CDSS group (4.9% vs. 3.4%; p = 0.03). There was a significant reduction in fluoroquinolone prescribing in abscess (8.5% vs. 4.9%; p = 0.003), dental abscess (4.4% vs. 0%; p < 0.00001), sinusitis (2.4% vs. 0.2%; p < 0.00001) and soft skin tissue infections (5.3% vs. 0.8%; p < 0.00001). In the fluoroquinolone subgroups, prescribing per provider type and appropriate dosing per renal function were similar, and there were no adverse events leading to an ED visit or hospitalization within 90 days. Conclusion Implementation of a CDSS resulted in a reduction of overall and targeted indication inappropriate fluoroquinolone prescribing. Disclosures Teri Fanizza, Pharm.D., BCPS, BCIDP, Merck & co inc: Stocks/Bonds|Pfizer Inc: Stocks/Bonds.

ODP499 Myxedema Coma: A Challenging Presentation of an Uncommon Disease

Abstract Myxedema coma is a rare diagnosis but if not early recognized, this medical emergency possesses a high mortality rate. Over the years, it has been described predominantly in elderly women with history of hypothyroidism and as a precipitant factor that converges to evolve in a full presentation. We report a case of myxedema coma in a young male without risks for this disease. A 38 y/o Latin-American male with medical history ofhepatitis C virus and intravenous drug abuser that was brought to the emergency department after being found in the streets. The patient was agitated, oriented only to person, had slurred speech and reports last dose of heroin was two days ago. Denied other condition or medications. Vital signs BP 103/90mmHg, pulse: 41 bpm, T: 35.8°C RR: 19 rpm, SPO2: 99% at room air and BMI: 23.9. kg/m 2 . Physical examination pertinent for a disheveled male with anasarca, diffused dry skin with piloerection without surgery scars, non-palpable nor tender thyroid gland, bilateral exophthalmos, decreased bowel sound, positive fluid wave and abdomen diffusely tender to palpation with bilateral lower extremities infected ulcers. Blood workup showed impaired renal function, severe azotemia, hyponatremia, hypoglycemia and normocytic anemia. TSH 147uIU/mL. Imaging studies remarkable for bilateral pleural effusions, intestinal ileus, and negative brain CT scan. Patient was admitted with diagnosis of uremic encephalopathy, drug withdrawal and soft skin tissue infection. Patient was treated with emergent hemodialysis, drug withdrawal measures and IV antibiotics. Despite treatment, patient's clinical condition began to decline. He was found obtunded requiring endotracheal intubation. TSH was persistently elevated in 55.7uIU/mL with suppressed free T4 <0.42ng/dL. Patient noted with persistent sinus bradycardia, hypothermia, ileus, ascites, bilateral pleural effusions, and hypotension. Patient was consulted to endocrinology department who evaluated the overall clinical presentation and myxedema coma was diagnosed. He was treated with levothyroxine 100mg IV for two days, but eventually developed multiorgan failure and unfortunately died. Myxedema coma is a complication of severe hypothyroidism that slows down the functions of multiple organs and directly affects their function. It is an endocrinologic emergency that leads to decline of the clinical presentation of patients. The epidemiology favors this presentation in patients with history of hypothyroidism, more specifically elderly women. Multiple conditions may present with similar signs and symptoms. Physicians must be aware that myxedema coma must be suspected in a patient with altered mental status, hypothermia, hypoglycemia, hypotension, anasarca among others even in the presence of more common conditions and in rare populations like our patient. Opioid Induced Endocrinopathies still remain a complication that is underdiagnosed. The aim of this case is to createmedical awareness on the importanceto consider myxedema coma in patients with Opioid abuse and withdrawal. Presentation: No date and time listed

Transdermal Delivery of High Molecular Weight Antibiotics to Deep Tissue Infections via Droplette Micromist Technology Device (DMTD).

Wound infection by multidrug-resistant (MDR) bacteria is a major disease burden. Systemic administration of broad-spectrum antibiotics colistin methanesulfonate (CMS) and vancomycin are the last lines of defense against deep wound infections by MDR bacteria. However, systemic administration of CMS and vancomycin are linked to life-threatening vital organ damage. Currently there are no effective topical application strategies to deliver these high molecular weight antibiotics across the stratum corneum. To overcome this difficulty, we tested if high molecular weight antibiotics delivered by Droplette micromist technology device (DMTD), a transdermal delivery device that generates a micromist capable of packaging large molecules, could attenuate deep skin tissue infections. Using green fluorescent protein-tagged E. coli and live tissue imaging, we show that (1) the extent of attenuation of deep-skin E. coli infection was similar when treated with topical DMTD- or systemic IP (intraperitoneal)-delivered CMS; (2) DMTD-delivered micromist did not spread the infection deeper; (3) topical DMTD delivery and IP delivery resulted in similar levels of vancomycin in the skin after a 2 h washout period; and (4) IP-delivered vancomycin was about 1000-fold higher in kidney and plasma than DMTD-delivered vancomycin indicating systemic toxicity. Thus, topical DMTD delivery of these antibiotics is a safe treatment for the difficult-to-treat deep skin tissue infections by MDR bacteria.

1361. Actinotignum schaalii an Under-recognized Cause of Infections: A Case Series in Calgary from 2012 - 2020

Abstract Background Actinotignum schaalii is a gram-positive rod that is a fastidious commensal of the urogenital tract. Infections with A. schaalii are underdiagnosed previously because phenotypic methods fail to identify it. Both MALDI-TOF mass spectrometry and 16S rRNA sequencing allow definitive identification of this opportunistic emerging pathogen. A. schaalii is an infrequent but important cause of UTIs in the elderly, particularly with urological abnormalities. The spectrum of invasive disease caused by A. schaalii is not well characterized; however, it has been isolated in severe infections including necrotizing skin and soft tissue infections, bacteremia, osteomyelitis, and endocarditis. We used a population-based approach to characterize and describe the clinical and microbiological features of invasive A. schaalii infections in our region. Methods All adult and pediatric cases enrolled had microbiological isolates of Actinotignum schaalii recovered from blood cultures, sterile fluids and tissue cultures from Jan 2012 to Dec 2020 by APL, a regional centralized microbiology laboratory serving the Calgary Zone in Alberta, Canada. Clinical data were retrieved and linked from administrative health databases, chart review and the laboratory information system. Standard descriptive statistics were used. Results We identified 84 unique A. schaalii infections, 35 were from bloodstream, 32 soft tissue, 7 post-operative infections. Median age and Charslon comorbidity score was higher in BSI. 54.3% of patient with BSI had a genitourinary pathology, with 51.4% caused by a complicated urinary infection, while soft and skin tissue infections caused 65.3% of non-BSI. Using EUCAST MIC cut-offs, 48% and 100% of the isolates were resistant to clindamycin and metronidazole, respectively. In contrast, all specimens were susceptible to penicillin. Hospitalization and 90-days mortality were higher in the BSI group. Conclusion A. schaalii is an anaerobic opportunistic pathogen that can cause life-threatening invasive infections, particularly in older adults with underlying genitourinary pathology. BSI were associated with higher rates of hospitalization and mortality. In contrast, patients with A. schaalii isolated from cutaneous sources were younger and had better clinical outcomes. Disclosures All Authors: No reported disclosures

Diagnosis of infectious factors in patients with chronic glomerular disease using deep learning‐based health information data

AbstractThe study was aimed to explore the effect of information health data based on deep learning of neural network to diagnose the infectious factors of patients with chronic glomerular disease (CGD) and evaluate its diagnostic effect. Ninety patients with CGD were selected and randomly rolled into control group A, control group B, and observation group, with 30 cases in each group. Big data scientific research analysis platform was used for data integration, convolutional neural network (CNN) was employed for feature analysis, correlation analysis, and screening of disease‐related biomarkers. The patients were diagnosed by observation of symptoms and signs, combined diagnosis of blood test and urine test, and information health data diagnosis based on deep learning CNN. As a result, the specificity, sensitivity, and accuracy of information health data diagnosis based on deep learning CNN were 78.9%, 87.6%, and 92.1%, respectively. The main sources of infections in patients were lung infections, bloodstream infections, urinary system infections, skin and soft tissue infections, and upper respiratory tract infections. Amongst them, lung infection accounted for the highest proportion, reaching 65.4%, followed by blood infection (11.2%) and skin tissue infection (9.6%). The pathogens of infection were mainly bacteria, viruses, fungi, tuberculosis, and pneumocystis pneumonia (PCP), amongst which bacterial infections accounted for the highest proportion (31.5%), followed by PCP (25.6%). In short, the information health data based on deep learning CNN had high specificity, sensitivity, and accuracy for the diagnosis of CGD. The main infectious factors of CGD were pulmonary infection and blood infection, and the pathogens were mainly bacteria and viruses.

Effectiveness and safety of Liuhedan for treating cellulitis: A protocol for systematic review and meta-analysis.

Background:Liuhedan is a famous traditional Chinese Medicine formula used to treat cellulitis in China. However, there are no systematic reviews for the evidence and the therapeutic effectiveness and safety of Liuhedan for treating cellulitis. The aim of this study is to summarize previous evidence, assessing the efficacy and safety of Liuhedan treating cellulitis.Methods:We will search the EMBASE, WANFANG DATA, Web of Knowledge, CNKI, PubMed, ClinicalTrials.gov, and Cochrane Library from inception to June 30, 2021 to retrieve relevant studies using the search strategy: (“Liuhedan” OR “Liuhe Pill” OR “Liu-He-Dan”) AND (“cellulitis” OR “phlegmon” OR “skin and soft tissue infection” OR “skin tissue infection” OR “soft tissue infection”). Two authors independently judged study eligibility and extracted data. Heterogeneity will be examined by computing the Q statistic and I2 statistic.Results:This study assessed the efficiency and safety of Liuhedan for treating cellulitis.Conclusions:This study will provide reliable evidence-based evidence for the clinical application of Liuhedan for treating cellulitis.Ethics and dissemination:Ethical approval is unnecessary as this protocol is only for systematic review and does not involve privacy data. The findings of this study will be disseminated electronically through a peer-review publication or presented at a relevant conference.

Recurrence of Skin and Soft Tissue Infections

Skin and soft tissue infections (SSTIs) are a common manifestation of Staphylococcus aureus (SA) and have widely variable recurrence rates. To

Isolation and Laboratory Diagnosis of Antibiotic-resistant E. coli from Surgical Wounds of Inpatients at Zagazig University Hospitals, Egypt

E. coli is one of the most common community and nosocomial pathogens and it mainly causes skin and soft tissue infections. So, the current study aimed to study the isolation of antibiotic-resistant E.coli strains in Egypt, Hospitals. Study their antibiotic susceptibility profile and therapy to control and present the transmission of E. coli strains among the health care settings.120 pus samples were collected from post-operation wounds of a study group of inpatients in Egypt, Hospitals. Bacteria colonizing the wounds were isolated on specific culture media thereafter purified and divided into 4 groups depending on their morphological characters and Gram's stain reaction Isolated bacteria were divided into 4 groups. Group (I) represented 40% of total isolates; while group (II) & (III) represented 25% and group (IV) 22%. Isolated bacteria related to groups I, II, III & IV were preliminary identified as S. aureus. E. coli, K. pneumoniae and P. aeruginosa, respectively. Antibiotic susceptibility of the 4 groups of isolated bacteria against 10 different antibiotics revealed that Ciprofloxacin showed the highest activity against E. coli. Data revealed that strain encoded E.coli 6 is a multi-resistant strain as it resisted 13 antibiotics out of 15 (86.7%).

Skin and Soft-Tissue Infections

Sorting through the myriad of causes of soft tissue infections can be a daunting diagnostic challenge to even the astute clinician. While much is written about empiric treatment of skin and soft tissue infections, it is important to make a correct diagnosis, since clinical findings in common versus exotic and mild versus life-threatening infections have significant overlap. Historical information, such as the temporal progression of signs and symptoms, travel history, animal exposure, age, occupation, bite history, underlying diseases, and lifestyle, is important in focusing the differential diagnosis toward specific causes. Still, clinical assessment is frequently not sufficient and laboratory tests, radiographic imaging, and surgical intervention may be necessary to establish a specific diagnosis and to provide the rationale for definitive management.

A Very Uncommon Case of Infective Endocarditis

Acinetobacter is a gram-negative coccobacillus associated with various hospital-acquired infections and community-acquired infections including pneumonia as well as urinary tract, skin, and soft tissue infections. Acinetobacter is a rare cause of infective endocarditis reported mainly in hospitalized patients with risk factors, and typically presents with severe disease.

Isolation of Lytic Bacteriophage Cocktail Against Methicillin-Resistant Staphylococcus Aureus Isolated From Human Skin Infections

Methicillin-resistant Staphylococcus aureus MRSA is a S. aureus that resistant to β-lactam antibiotics (e.g., Cefoxitin and Oxacillin). MRSA has a tremendous capacity to develop resistance to other classes of antibiotics and forming a real threat to patients. The process of exploring a new tactic of non-antibiotic treatments has become an urgent need. A bacteriophage is one of the possible treatments that strongly suggested. Bacteriophages are viruses that infect bacteria as a natural host with a bactericidal capability against multidrug-resistant bacteria that do not respond to conventional antibiotics. The current study investigates the lytic efficacy of phage-cocktail in vitro, specifically against S. aureus isolated from skin infections and find out the possible association of phage-antibiotic resistance. A total of 43 isolates of Methicillin-resistant staphylococcus aureus were isolated from skin infections. The isolates are distributed as (10 isolates of burn, 4 isolates of diabetic foot ulcer, 7 isolates of surgical wounds, 3 isolates of pressure ulcer, and 19 of skin and soft tissue infection). The isolates exhibited variant antibiotic susceptibility against 12 antibiotics (Cefoxitin FOX, Vancomycin VAN, Oxacillin OX, Rifampin RA, Chloramphenicol C, Nitrofurantoin F, Clindamycin DA, Azithromycin AZM, Amikacin AK, Trimethoprim-sulfamethoxazole SXT, Ciprofloxacin CIP, and Gentamicin CN). A bacteriophage cocktail was isolated using a phage-enrichment technique, high titer phage lysate (5*109 pfu/ml) was obtained and investigated against 43 MRSA isolates. The phage-cocktail showed high specificity to S. aureus but variable susceptibility to 43 MRSA isolates. It was observed that there was no association (p greater than 0.05) between phage and antibiotic resistance of (FOX, OX, VAN, RA, C, F, and DA) where the significant association was observed (p less thaN 0.05) with (AZM, AK, SXT, CIP, and CN). Significantly, the more antibiotic-resistant isolates exhibited more sensitivity to phage-cocktail, which represents a promising alternative to antibiotics that do not affect with increasing antibiotic resistance. How to cite this article: Hantoosh, S.M. and Jarallah, E.M. (2019). Isolation of Lytic Bacteriophage Cocktail Against Methicillin-Resistant Staphylococcus Aureus Isolated From Human Skin Infections. International Journal of Drug Delivery Technology, 9(4): 623-629. Source of support: Nil. Conflict of interest: None.

Potential savings through single-dose intravenous Dalbavancin in long-term MRSA infection treatment - a health economic analysis using German DRG data.

Complicated infections such as osteomyelitis, skin and soft tissue infections or endocarditis often require antibiotic therapies that can last up to several weeks. The prolonged hospital length of stay (LOS) leads to a dramatic increase in costs. Single-dose intravenous Dalbavancin is a novel antimicrobial agent for the treatment of acute bacterial skin, skin structure and soft tissue infections (ABSSSI) that allows an earlier discharge of patients, resulting in potential savings. Joint, bone and prostheses infections (JBPI) are also related with long LOS. The aim of this study is to determine the economic effects of single-dose intravenous Dalbavancin in suitable patients with Methicillin-resistant Staphylococcus aureus infections in Germany. For this purpose, an analysis with real-world patient treatment data was performed, which was subsequently validated in a large German hospital. In total, ABSSSI patients with MRSA infections could stay 6.45 days shorter and 2,865 € could be saved while JBPI patients could be discharged eventually 10.6 days earlier and 3,909 € could be saved. Single-dose intravenous Dalbavancin is thus an option for patients with ABSSSI and JBPI who are eligible for discharge.

Clinical characteristics of elderly patients with sepsis combined with heart failure and the risk factors analysis

Objective To investigate clinical characteristics of elderly patients with sepsis combined with congestive heart failure and risk factors for short-term mortality. Methods Clinical data of elderly patients with sepsis combined with congestive heart failure who were admitted in our hospital from January 2013 to January 2018 were selected and retrospectively analyzed.They were divided into the survival group(n=134)and the death group(n=83)according to survival status during hospitalization.The clinical characteristics and risk factors for mortality were analyzed and compared. Results A total of 217 elderly patients were enrolled, with 113 males and a mean age of(72.3±7.5)years.The death rate of sepsis was 38.3%(83/217 cases), and 29 cases died of sepsis and 54 cases died of other diseases.Pneumonia accounted for 78.8%(171/217 patients)in all patients of two groups, and skin and soft tissue infection for 12.9%(28/217 cases). There were significant differences between two groups in age, body mass index, smoking, diabetes, chronic obstructive pulmonary disease, mean arterial pressure, arterial oxygen partial pressure(PaO2), C-reactive protein, white blood cell counts, neutrophil and lymphocyte counts, glomerular filtration rate, serum sodium level, albumin level, lactate level, and left ventricular ejection fraction(P<0.05). Furthermore, the rates of invasive mechanical ventilation and continuous renal replacement therapy were higher in the death group than in the survival group(χ2=13.209 and 7.402, P<0.001 and 0.007). Multivariate Cox regression analysis showed that advanced age, chronic obstructive pulmonary disease, low albumin level and low glomerular filtration rate were risk factors for mortality(P<0.05). Conclusions Elderly patients with sepsis combined with congestive heart failure often have severe pneumonia and violent skin and soft tissue infection, with worse heart and renal function.Advanced age, chronic obstructive pulmonary disease, low albumin level and low glomerular filtration rate are risk factors for mortality. Key words: Sepsis; Heart failure; Risk factor

Molecular characteristics and antimicrobial susceptibility to Staphylococcus aureus strains isolated from children with skin and soft tissue infections

Objective To investigate the molecular characteristics, virulence genes and antimicrobial susceptibility to Staphylococcus aureus strains isolated from children with skin and soft tissue infections(SSTIs) in Beijing. Methods A total of 52 Staphylococcus aureus isolates were collected from children with SSTIs in Beijing Children′s Hospital, Capital Medical University, and the clinical data were collected and analyzed.Methicillin-resistant Staphylococcus aureus(MRSA) and methicillin-susceptible Staphylococcus aureus(MSSA) were identified by using the cefoxi-tin disc method and the detection of mecA gene.Multilocus sequence typing (MLST) and staphylococcal protein A(spa) typing were analyzed by the PCR method, and the staphylococcal chromosomal cassette mec (SCCmec) type was analyzed for the MRSA isolates.The pvl, eta, etb, tsst-1 and hlg genes were also detected by PCR.The susceptibility strains to 16 antibiotics were evaluated by using the agar dilution method. Results A total of 52 Staphylococcus aureus SSTIs patients, 30 with MRSA infections and 22 with MSSA infections were included in the study.There were 23 patients (44.2%) less than 1 year old.The most frequent infections were the newborn omphalitis (12/52 strains, 23.1%)and abscess(11/52 strains, 21.2%). ST59-MRSA-SCCmecⅣa-t437 was the most predominant clones of MRSA isolates.Among the MSSA isolates(14/30 strains, 46.7%), no significant epidemic clone was found.Ten sequence types (STs) and 14 spa types were identified in MSSA, and the most common types were ST22(6/22 strains, 27.3%)and t309(5/22 strains, 22.7%), respectively.Notably, the multidrug resistant rates of MRSA and MSSA isolates were all >85%.The percentages of the Staphylococcus aureus SSTIs strains resistant to Erythromycin, Penicillin, Chloramphenicol and Clindamycin were 100.0%, 94.2%, 69.2% and 63.5%, respectively.The tested isolates were susceptible to Trimethoprim/Sulfamethoxazole, Mupirocin, Fusidic acid, Tigecycline, Linezolid and Vancomycin.The pvl gene′s positive rate was 40.4%, and no significant difference between MRSA and MSSA was observed (P>0.05). Eta and etb genes were detected in 2 patients with staphylococcal scalded skin syndrome. Conclusions The Staphylococcus aureus SSTIs strains are most frequently isolated from newborn omphalitis and abscess in Beijing.The multidrug resistant rate is relatively high, so the erythromycin and clindamycin should not be preferred in empiric treatment of children with Staphylococcus aureus SSTIs.The prevalence of pvl gene is 40.1%.ST59-MRSA-SCCmecⅣa-t437 is the common clone of MRSA, while the MSSA isolates have a more diverse genetic background. Key words: Staphylococcus aureus; Skin and soft tissue infections; Molecular characteristics; Virulence; Antimicrobial susceptibility; Child

Molecular characteristics of Staphylococcus aureus isolated from intensive care units of children's hospital

Objective To study the molecular characteristics of the Staphylococcus aureus isolated from the intensive care units (ICUs) of children's hospital. Methods From January 2016 to December 2016, a total of 39 S. aureus strains were collected and identified from various clinical specimens that were obtained from patients who were confined in the neonatal and pediatric ICUs of Beijing Children's Hospital. Methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) were identified using the cefoxitin disc method and the detection of the mecA gene. Multilocus sequence typing (MLST) and spa typing were analyzed using the PCR, and the staphylococcal chromosomal cassette mec (SCCmec) type was analyzed for the MRSA isolates. Twenty-one superantigen genes and the Panton-Valentine leukocidin (pvl) gene were also detected by PCR. Their susceptibility to 12 antibiotics was evaluated using the E-test method. The differences in prevalence of virulence genes and antimicrobial resistance were compared between the MRSA and MSSA isolates by Fisher's exact test. Results All the S. aureus strains were isolated from secretion inside the airway of pneumonia (including severe pneumonia), the blood of patients with bacteremia, and exudate of skin and soft tissue infections. ST59-SCCmecⅣa-t437 (55.6%) and ST398-t571 (28.6%) were the most predominant clones of MRSA and MSSA, respectively. Of the 39 isolates, 26 strains (66.7%) had at least one superantigen gene, and seb (38.5%), sek (30.8%), and seq (20.5%) were the most common genes; seb-sek-seq (18.0%) was the main virulence genotype. The pvl gene's positive rate was 25.6%, and no significant difference between MRSA and MSSA was observed (P>0.05). Notably, 79.9% of the S. aureus isolates were multidrug resistant, and 94.9%, 53.8%, and 51.3% of the isolates were resistant to erythromycin, clindamycin, and chloramphenicol, respectively. The tested isolates were susceptible to trimethoprim/sulfamethoxazole, rifampicin, and vancomycin. Conclusions The S. aureus strains from the ICUs of children's hospital were isolated from the secretion inside the airway of pneumonia (including severe pneumonia), the blood of patients with bacteremia, and exudate of skin and soft tissue infections. ST59-SCCmecⅣa-t437 (55.6%) and ST398-t571 (28.6%) were the common clones of MRSA and MSSA, respectively. The prevalence of superantigen genes and the multidrug resistant rate were relatively high. Key words: Staphylococcus aureus; Methicillin-resistant Staphylococcus aureus; Pediatric; Intensive care unit; Molecular characteristics; Virulence; Antimicrobial susceptibility; Multidrug resistance

Multicenter study on the molecular characteristics of community-associated Methicillin-resistant Staphylococcus aureus in children with skin and soft tissue infection

Objective To explore the molecular characteristics of community-associated Methicillin-resis-tant Staphylococcus aureus (CA-MRSA) from children with skin and soft tissue infection (SSTIs) in China. Methods CA-MRSA was collected from the outpatients in Department of Dermatology in 13 Children′s Hospitals of China.Genotypic characteristics of CA-MRSA isolates were tested by adopting multilocus sequence typing (MLST), staphylococcal protein A (spa) typing and Staphyloccoccal cassette chromosome mec (SCCmec) typing.And the presence of Panton-Valentine leukocidin genes(pvl) was determined also. Results Overall, 1 705 strains of Staphylococcus aureus were isolated from SSTIs children, and CA-MRSA accounted for 2.6% (44/1 705 strains). Two types of SCCmec were detected in all the CA-MRSA strains, and the main types were SCCmec Ⅳ and SCCmec Ⅴ, accounting for 45.5% (20/44 strains) and 54.5% (24/44 strains), respectively.Thirteen MLST types (STs) and 15 spa types were detected among CA-MRSA.The most prevalent MLST was ST121 (18/44 strains, 40.9%), followed by ST59 (9/44 strains, 20.5%). Additionally, t437 was predominant, accounting for 40.9% (18/44 strains). ST121 strain had 8 spa types, and t2086 was the most common type (6/18 strains, 33.3%); while ST59 had only 1 spa type, t437.No ST121, ST59 and t437 strains were found in Central and Eastern region of China.Only 4 (9.1%) of the 44 CA-MRSA strains harbored pvl genes which were all from Southern region. Conclusions The most common clone of SSTIs CA-MRSA in children is MRSA-ST121- SCCmec Ⅳ/Ⅴ, as the molecular epidemiology of CA-MRSA strain has changed, ST121 has replaced ST59 to become the main epidemic strains. Key words: Community-associated Methicillin-resistant Staphylococcus aureus; Skin and soft tissue infection; Molecular characteristics; Child; China

Methicillin-resistant Staphylococcus aureus strains carrying Panton-Valentine leukocidin genes: clinical and molecular characteristics

Objective To isolate and identify the methicillin-resistant Staphylococcus aureus (MRSA) strains carrying Panton-Valentine leukocidin genes (pvl+ -MRSA) from clinical samples and to further understand their molecular characteristics and infections caused by them. Methods Drug susceptibility test was performed to detect the drug resistance in 259 MRSA strains. pvl+ -MRSA strains were screened out from those MRSA strains using cefoxitin slip test and mecA gene detection by PCR. Multiple PCR and multilocus sequence typing (MLST) were used for SCCmec and ST typing. Pulsed-field gel electrophoresis (PFGE) and cluster analysis were used to understand the genetic and epidemic features of the pvl+ -MRSA strains. Different types of infections and diseases caused by the pvl+ -MRSA strains were analyzed. Results Among the 259 MRSA strains, 51 pvl+ -MRSA strains were identified (19.7%, 51/259), of which 29 and 22 strains were respectively isolated from patients with community-acquired and hospital-acquired infections. ST59-SCCmecⅢ (35.3%, 18/51) was the predominant type of the 51 pvl+ -MRSA strains, followed by ST59-SCCmecⅣ(25.5%, 13/51). But no predominant clone among those strains was revealed by the result of PFGE. Children, young- and middle-aged patients (≤44 years old) had a significantly higher positive rate of pvl+ -MRSA than patients aged ≥45 years (P<0.05). Skin and soft tissue infection (47.1%, 24/51) was the most common disease caused by the pvl+ -MRSA strains (P<0.05), followed by pneumonia (17.6%, 9/51). The pvl+ -MRSA strains showed lower resistance to levofloxacin, gentamycin and rifampicine (7.8%-21.6%). No moxifloxacin-, nitrofurantoin- or linezolid-resistant pvl+ -MRSA strains were identified. Conclusion The rate of pvl+ -MRSA infection is high in the local population. ST59-SCCmecⅢ and ST59-SCCmecⅣ are the predominant types of pvl+ MRSA strains. Children, young- and middle-aged persons are the susceptible population. Skin and soft tissue infection and pneumonia are the common diseases caused by pvl+ -MRSA. Key words: Methicillin-resistant Staphylococcus aureus; Infection; Panton-Valentine leucocidin; Molecular typing; Disease type

Molecular characterization of Staphylococus aureus isolated from Greek adults with Soft Skin Tissue Infections (SSTIs)

Molecular characterization of Staphylococus aureus isolated from Greek adults with Soft Skin Tissue Infections (SSTIs)

Molecular characteristics and virulence factors of Staphylococcus aureus isolated from skin and soft tissue infections in Urumqi

Molecular characteristics and virulence factors of Staphylococcus aureus isolated from skin and soft tissue infections in Urumqi