Epidemiology and microbiology of skin and soft tissue infections.

PURPOSE OF REVIEW: Skin and soft tissue infections (SSTIs) are a broad spectrum of diseases, including uncomplicated and complicated infections. Herein, we review the current epidemiology and microbiology of SSTIs. RECENT FINDINGS: In the last decades, a significant growing trend of SSTIs both in the community and healthcare settings with a dramatic increase of the economic burden for these diagnoses was observed. Several observational studies found that SSTIs are a substantial cause of ambulatory and emergency department visits, and of hospitalizations. Although, microbiology of SSTIs changes according to the clinical feature and the severity of illness, Staphylococcus aureus being the leading cause of both uncomplicated infections and complicated infections. Moreover, the increasing prevalence of infections because of multidrug-resistant bacteria, mainly methicillin-resistant S. aureus (both community-acquired and healthcare-associated methicillin-resistant S. aureus), are associated with significantly increased morbidity, mortality, length of hospital stay, and costs, compared with infections because of susceptible strains. Moreover, although it is unclear whether high vancomycin minimum inhibitory concentration is associated with a worse outcome, it poses a further challenge for the clinicians. SUMMARY: The understanding of the current epidemiology and microbiology of SSTIs is indicated for an appropriate antimicrobial therapy and an overall optimal management of SSTIs.

Combination antibiotic therapy for the treatment of infective endocarditis due to enterococci.

INTRODUCTION: Enterococci are common causes of infective endocarditis (IE) in both health care and community-based setting. Enterococcal IE requires bactericidal therapy for an optimal outcome. For decades, cell-wall-active antimicrobial agents (penicillins or vancomycin) in combination with aminoglycosides were the cornerstone of the treatment; however, the emergence of antibiotic resistance has significantly reduced the efficacy of these regimens. MATERIALS AND METHODS: Data for this review were identified by searches of MEDLINE and references from relevant articles on antibiotic combination regimens for the treatment of enterococcal IE. Abstracts presented in scientific conferences were not searched for. CONCLUSION: New effective and safe combination treatments, including double-ß-lactam and daptomycin/ß-lactam combination, are proving useful for the management of IE due to enterococci.

Update on treatment of COVID-19: ongoing studies between promising and disappointing results.

The COVID-19 pandemic represents the greatest global public health crisis since the pandemic influenza outbreak of 1918. We are facing a new virus, so several antiviral agents previously used to treat other coronavirus infections such as SARS and MERS are being considered as the first potential candidates to treat COVID-19. Thus, several agents have been used by the beginning of the current outbreak in China first and all over the word successively, as reported in several different guidelines and therapeutic recommendations. At the same time, a great number of clinical trials have been launched to investigate the potential efficacy therapies for COVID-19 highlighting the urgent need to get as quickly as possible high-quality evidence. Through PubMed, we explored the relevant articles published on treatment of COVID-19 and on trials ongoing up to April 15, 2020.

[Skin and soft tissue infections: current therapeutic options]. / Infezioni della cute e dei tessuti molli: opzioni terapeutiche.

In the present review, the authors focus on skin and soft tissue infections (SSTIs), a set of commonly observed pathologies which can present different features in terms of site and localization, clinical characteristics, and the aetiological agent responsible; their severity is related to the depth of the affected sites. After a brief introduction to the diverse classification criteria which are currently adopted by various authors, the aetiology and role of the most frequently occurring pathogen, Staphylococcus aureus, often methicillin-resistant is discussed, as well as the possible therapeutic options. We first present the internationally recommended guidelines, and stress that SSTI management has to conform to different criteria, in accordance with the different clinical settings: mild infections require simple and cost-saving treatments while severe infections make timely and aggressive treatments mandatory. The review then reports the recent data concerning the efficacy of new antimicrobials for treating SSTIs. In particular, results observed with linezolid, tigecycline, and daptomycin are discussed.

New insights into classification, epidemiology and microbiology of SSTIs, including diabetic foot infections.

Skin and soft tissue infections (SSTIs) involve a heterogeneous group of entities with different clinical presentations classified according to several specific criteria. Because of their great variability, their incidence and prevalence is difficult to accurately determine. Yet it is generally thought that the rate of SSTIs is globally increasing due to an aging population, strictly associated with the increase in the number of critical and immunocompromised patients. The aetiology of SSTIs is also extremely variable, reflecting the noteworthy heterogeneity of their clinical presentations and their epidemiology. Gram-positive are far more prevalently than Gram-negative cocci responsible for STTIs globally considered including both aerobe and anaerobe microorganisms. The emergence of multidrug-resistance bacteria represents a serious public health threat which is making antimicrobial therapy less efficacious and more challenging by the day.

Antibiotic resistance in long-term care facilities.

Long-term-care facilities (LTCFs) comprise a heterogeneous group of institutions that provide a wide variety of services to diverse groups of patients, most of whom are elderly. Infections are common in LTCFs and these are complicated by antimicrobial-resistant pathogens. The residents in LTCFs have a high frequency of colonization with antimicrobial-resistant organisms, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, penicillin-resistant pneumococci, extended spectrum P-lactamase-producing gram-negative organisms, and fluoroquinolone-resistant gram-negative organisms. Although several control programs have been published, up to now there still is a long way to go in this area of health care. This review will briefly touch upon the clinical relevance of antimicrobial resistance in LTCFs.

Deep tissue biopsy vs. superficial swab culture, including microbial loading determination, in the microbiological assessment of Skin and Soft Tissue Infections (SSTIs).

Thirty-two patients affected by SSTIs including DFIs were enrolled between 2013 and 2014. Superficial swab was obtained before and after cleansing with sterile saline, and after ultrasonic debridement; deep tissue biopsy was obtained from ulcer base. Samples were diluted with 1 mL of saline, serial 10-fold dilutions to 10-6 were made and 50 µL of each dilution was plated onto appropriate media. Bacteria were identified by Vitek II system. Microbial load was expressed as CFU/mL. Statistical analysis was performed by χ2. Incidence of Gram positives was higher than Gram negatives (S. aureus and P. aeruginosa being the most frequent); concordance (same bacteria isolated before and after debridement) never exceeded 60%. Ultrasonic debridement significantly reduced bacterial load or even suppressed bacterial growth. While reliability of superficial swab is poor for microbiological diagnosis of SSTIs, swabbing after ultrasonic debridement and biopsy of the ulcer base may be equally reliable.

[In vitro activity of prulifloxacin, levofloxacin and ciprofloxacin against urinary pathogens]. / Attività in vitro di prulifoxacina, levofoxacina e ciprofloxacina nei confronti di patogeni urinari.

The present investigation aimed to compare the in vitro antimicrobial activity of prulifloxacin to that of levofloxacin and ciprofloxacin against recently urinary pathogens. From our large bacterial collection, 978 non-duplicated clinical isolates, derived from patients urinary infections, maintained with minimal sub-culture deep frozen at -70 degrees C in a matrix of Brain Heart Infusion broth +20 % glycerol were tested to determine MICs of prulifloxacin, levolfoxacin and ciprofloxacin by means of broth microdilution technique. For Gram negartive bacteria, no significant diffrences was observed between all three antibiotics. Enterobacteria showed a resistance rate ranging between 6% (Enterobacter spp) and approximately 20% (Escherichia coli). Antibiotic resistance of Pseudomas spp was higher (30.3%). For Gram positive, all methicillin-susceptible Stalphylococcus aureus strains were sensitive whereas 30% of methicillin-resistant and enterococci were resistant to all three antibiotics. Purification exerts its antibacterial activity at lower concentrations than ciprofloxacin and levofloxacin. The in vitro activity of prulifloxacin against urinary pathogens and its high and prolonged urinary concentration following a single oral dose, suggest that for treatment of urinary prulifloxacin is an alternative to other flouroquinolones for treatment of urinary tract infections.

Changing modalities of outpatient parenteral antimicrobial therapy use over time in Italy: a comparison of two time periods.

This study aimed to assess the extent and nature of recent changes in the management of outpatient parenteral antimicrobial therapy (OPAT) in Italy. We reviewed our previously reported data from 1999 to 2003 and compared them with data from patients who received OPAT from 2005 to 2010. Data for 1175 patients who received OPAT were analysed. Skin and soft tissue infections (SSTIs) were the most common infection treated with OPAT in both time periods, but an increase in patients with SSTIs receiving OPAT was observed. By contrast, a decline over time of OPAT use was found for patients affected by pneumonia. Furthermore, ceftriaxone use declined, whereas teicoplanin increased over time. In conclusion, OPAT use has significantly changed over time in Italy.

Diagnostic and therapeutic appropriateness in bone and joint infections: results of a national survey.

The impact of infectious diseases (ID) specialist consultation in the management of many types of bacterial infections has been fully demonstrated but not for bone and joint infections (BJIs). Nineteen ID Italian centres collected of data from June 2009 to May 2012. Italian guidelines (2009) were used to determine the appropriateness of the diagnostic and therapeutic process of BJIs before and after consulting an ID specialist. Data on 311 patients were collected: 111 cases of prosthetic joint infection, 99 osteomyelitis, 64 spondylodiscitis and 37 fixation device infection. A significant increase of microbiological investigations, imaging techniques and blood inflammation markers were noted after consulting the ID specialist. Moreover, inappropriateness of treatment duration, dosage, and number of administrations significantly decreased after consultation. Infectious disease specialist intervention in the management of BJIs significantly increases the appropriateness both in performing instrumental and laboratory analysis, but especially in determining the correct therapy.

[Treatment of acute otitis media in paediatrics: a meta-analysis]. / Trattament dell'otite media acuta in età pediatrica: una metanalisi.

Otitis represents the second most common infection of the upper respiratory tract, its treatment being the most common cause for prescribing antibiotics in the United States. A large number of antimicrobials, especially beta-lactams and macrolides, are generally used for treating acute otitis media (AOM) in paediatric patients, owing to their antibacterial spectrum including the main aetiological pathogens. Efficacy, safety and compliance of Cefaclor were compared with those of other antibiotics in the treatment of paediatric AOM in a meta-analysis of randomized controlled trials published between 1981 and 2004. Overall, evaluations were performed on 24 studies (Medline/PubMed, keywords "Cefaclor and otitis") which proved eligible (jadad score > or = 1); sixteen out of the 24 studies were multicentre, seven were double-blind. Mostly, the comparator agent was a beta-lactam, in four and three cases it was a macrolide or the association trimethoprim-sulfamethoxazole, respectively. Efficacy and safety were end-points of all studies whereas only 9 studies evaluated compliance. For the majority of studies (16/24) Cefaclor was administered for 10-day course. The analysis was based on a 2 x 2 contingency table with classification by treatment and number of improvements/cures, side-effects, and compliance of individual studies. The global estimate of the effective treatments was obtained with the weighted mean of the log OR (Odd Ratio) according to Mantel-Haenszel and associated confidence intervals (CI) at 95%. All the calculations were performed using SAS v.8. Chi-square test was performed. Clinical efficacy evaluation, number of improvements/cures, did not evidence a statistically significant difference among Cefaclor and comparators (86.8% vs 88.7%; Odds Ratio 0.77, IC 0.61/0.94). In the Cefaclor-treated patients, adverse events were observed in a statistically significant lower percentage compared to other antibiotics: 13.3% vs 19.4% (P < 0.0001), diarrhoea and gastro-intestinal disturbances being the most frequently observed. Compliance was observed in a similar proportion in the two patient groups, Cefaclor and comparators (Cefaclor 88.1; comparators 91.1%) and the slight difference was not statistically significant (Odds Ratio 0.77, IC 0.39-1.15). The present meta-analysis proves that in the treatment of paediatric AOM Cefaclor exhibits a clinical efficacy equal to other antibiotics usually employed in this setting, similar compliance but superior safety.

[Changes in intestinal microflora following levofloxacin administration in laboratory animals]. / Modificazioni della flora batterica intestinale a seguito di somministrazione di levofloxacina in animali da laboratorio.

Administration of antimicrobial agent is the most frequent and significant cause of modifications to gastrointestinal bacterial microflora. The aim of the present study was to evaluate the impact on Gram-negative aerobic bacterial intestinal flora, the possible colonization of Candida spp. and the possible emergence of resistant bacterial strains in a ten rats group receiving levofloxacin at the dosage of 10mg/kg one a day for 5 consecutive days. Our result are in agreement with those of other studies and the reveal that Gram-negative aerobic bacteria are strongly suppressed during levofloxacin treatment. Neither colonization by Candida spp. nor emergence of resistant micro-organism to levofloxacin were observed. After 7 days from completing treatment, bacterial intestinal flora was restored in 8 out of 9 rats. Levofloxacin does not significantly affect intestinal microflora. Therefore, it may be suitable for selective decontamination of the gastrointestinal tract in immunocompromised patients, for prophylaxis of urinary tract infections and for treatment of intestinal bacterial infections.

Dalbavancin for the treatment of acute bacterial skin and skin structure infections.

Dalbavancin is a novel parenteral lipoglycopeptide antibiotic approved for the treatment of acute bacterial skin and skin structure infections (ABSSSIs) in adults. Dalbavancin is highly active against common Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). Dalbavancin has a prolonged half-life that allows for once weekly dosing. Phase III trials have demonstrated non-inferiority compared with vancomycin/linezolid in the treatment of ABSSSIs, including those sustained by MRSA.

Methicillin-resistant Staphylococcus aureus infections: role of daptomycin/ß-lactams combination.

Methicillin-resistant Staphylococcus aureus (MRSA) associated infection has become a worrisome issue worldwide. Glycopeptides are the backbone antibiotics for the treatment of MRSA infections. However, several reports have highlighted the limitations of vancomycin. Daptomycin is successfully used for the treatment of serious MRSA infections, however selection of resistant strains has been reported during daptomycin-monotherapy. This review will briefly discuss the available data on daptomycin/beta-lactam combination therapies for the treatment of MRSA infections.

Epidemiology and antibiotic resistance in a large Italian teaching hospital.

We focused our attention on susceptibility profile of Acinetobacter spp., Pseudomonas spp., and Klebsiella spp. isolated from biological specimens at the University Hospital of Salerno between June 2011 and October 2012. Acinetobacter, with a prevalence of Acinetobacter baumannii (97%) presented a high range of resistance to the antimicrobials considered, excluding colistin (COL). Klebsiella spp. isolates, with a prevalence of Klebsiella pneumoniae (90%), presented a variable pattern of resistance [from 9·8% for COL to 50% for levofloxacin (LEV)]. Extended-spectrum beta-lactamases production was detected in 15% of isolates. Most Pseudomonas isolates were P. aeruginosa with a high rate of resistance (95% to amoxicillin/clavulanate and trimethoprim/sulfamethoxazole, and <50% to the other antibiotics). Colistin remained the most effective drug tested. This study provided useful information of the local bacterial epidemiology hopefully permitting to establish a more effective empirical therapy, preventing the inappropriate use of antibacterial agents and possibly limiting the diffusion of antibacterial resistance.

Bacterial Epidemiology and Antimicrobial Resistance in the Surgery Wards of a Large Teaching Hospital in Southern Italy.

OBJECTIVES: Surgical infections represent an increasingly important problem for the National Health System. In this study we retrospectively evaluated the bacterial epidemiology and antimicrobial susceptibility of the microorganisms concerned as well as the utilization of antibiotics in the General and Emergency Surgery wards of a large teaching hospital in southern Italy in the period 2011-2013. METHODS: Data concerning non-duplicate bacterial isolates and antimicrobial susceptibility were retrieved from the Vitek 2 database. The pharmacy provided data about the consumption of antibiotics in the above reported wards. Chi-square or Fisher's exact test were used. RESULTS: In all, 94 Gram-negative were isolated in 2011, 77 in 2012, and 125 in 2013, Escherichia coli, Acinetobacter baumannii and Pseudomonas aeruginosa always being the most frequently isolated microorganisms. A. baumannii showed high rates of resistance to carbapenems (with values of 100% in 2011 and 2012) and low rates of resistance to tigecycline, colistin and amikacin. In the same years, there were respectively 105, 93, and 165 Gram-positive isolated. The rate of MRSA isolates ranged from 66% to 75% during the study period. CONCLUSIONS: Our results show no significant increase in antimicrobial resistance over the period in question, and a higher rate of both MRSA isolates and resistance to carbapenems in A. baumannii compared with other European data.

Macrolide-resistance genes in clinical isolates of Streptococcus pyogenes.

Macrolide-resistance genes were investigated in 103 macrolide-resistant strains of Streptococcus pyogenes, isolated from children with pharyngotonsillitis. The presence of mef(A), erm(B), and erm(TR) genes was detected by PCR. mef(A) was found in 48 out of 103 (46.6%) strains, whereas erm(B) was detected in 43 isolates (41.7%). All mef(A) strains showed a typical M phenotype (resistance to 14- and 15-membered macrolides, and sensitivity to lincosamides and streptogramin B), whereas erm(B) strains had the MLSB phenotype (resistance to macrolides, lincosamides, and streptogramin B antibiotics). erm(TR) was found in 10 strains, always together with other resistance genes. In seven cases erm(TR) was associated with erm(B), and three cases with mef(A). In two isolates with the M phenotype (1.9%), it was not possible to detect the presence of any of the three macrolide resistance genes tested. Inducible resistance to macrolides was shown for 24 out of the 53 MLSB strains. Analysis of macrorestriction fragment patterns by pulsed-field gel electrophoresis showed that erythromycin-resistant S. pyogenes are polyclonal, however each phenotype, MLSB and M, formed essentially homogeneous groups.

The decision-making process in antibacterial treatment of pediatric upper respiratory infections: a national prospective office-based observational study.

BACKGROUND: The identification of patient management practices and the sources of medical information is crucial for rationalizing the treatment of respiratory tract infections, whose high incidence, especially in children, makes them one of the maior areas of unnecessary health expenditure. MATERIALS AND METHODS: This national prospective study was designed to investigate the diagnostic and prescribing habits of 100 office-based pediatricians managing upper respiratory tract infections in 1111 pediatric patients (604 males, mean age 6.7962.77 years; 507 females, mean age 6.7362.8 years) sequentially enrolled when an antibiotic treatment was deemed necessary. RESULTS: The most frequently diagnosed diseases were acute tonsillopharyngitis (56.2%) and acute otitis media (18.1%). Penicillins were prescribed in 34.3% of the cases, cephalosporins in 38.1%, and macrolides in 26.1%: oral drugs accounted for 92.2% of the prescriptions. The treatments were administered once or twice daily in 75.8% of the patients, and prescribed for 8 days in more than 80%; 76.7% also received supportive or symptomatic treatment (antipyretics, corticosteroids, cough suppressants and non-steroidal anti-inflammatory drugs). Laboratory or radiologic investigations were rarely requested. The main sources of medical information indicated by the participating pediatricians were pharmaceutical companies (35.6%) and meeting or congress reports (27.3%). CONCLUSIONS: The results indicate that more active education is still needed to improve the decision-making processes of office-based pediatricians.

Ceftriaxone versus Other Antibiotics for Surgical Prophylaxis : A Meta-Analysis.

OBJECTIVE: To investigate possible differences in prophylaxis with ceftriaxone compared with other antimicrobial agents for surgical-site infections and remote infections such as respiratory tract infections (RTIs) and urinary tract infections (UTIs). METHODS: The efficacy of ceftriaxone was compared with that of other antibiotics in the perioperative prophylaxis of local (surgical wound) and remote (RTIs and UTIs) infections in a meta-analysis of randomised controlled trials published between 1984 and 2003. The analysis was based on a 2 x 2 contingency table with classification by treatment and number of infections obtained from individual studies. RESULTS: Evaluations were performed on 48 studies, for a total of 17 565 patients. Overall, 406 patients (4.8%) in the ceftriaxone group and 525 (6.3%) in the comparator group developed a surgical-site infection (log odds ratio [OR] -0.30 [CI -0.50 to -0.13]; p < 0.0001). RTIs were observed in 292 (6.01%) patients in the ceftriaxone group and in 369 (7.6%) patients in the comparator group, (log OR -0.30 [CI -0.55 to -0.09]; p = 0.0013). UTIs were reported for 2.2% of the ceftriaxone prophylaxis patients compared with 3.74% of the comparator group patients (log OR -0.54 [CI -1.18 to -0.16]; p < 0.0001). Overall, in clean surgery 195 (5.1%) and 234 (6.2%) patients developed a surgical site infection in the ceftriaxone and comparator groups, respectively (log OR -0.22 [CI -0.51 to 0.01]; p = 0.0476). RTIs were prevented for all but 1.57% of patients in the ceftriaxone group and 2.62% of patients in the comparator group (p = 0.01) in clean surgery, and for 9.54% of the ceftriaxone group versus 11.6% of the comparator group (p = 0.01) in clean-contaminated surgery. While results observed in clean surgery did not show statistically significant superiority of ceftriaxone in preventing UTI insurgence (log OR -0.21 [CI 0.0-0.65]; p = 0.7702), this was clearly shown in the clean-contaminated surgery. In fact, 4.47% of patients in the ceftriaxone group versus 7.52% of patients in the comparator group developed a UTI (log OR -0.56 [CI -1.25 to -0.16]; p < 0.0001). Adverse events were observed in a similar proportion in the ceftriaxone prophylaxis and the comparator groups (0.35% and 0.23%, respectively). Duration of prophylaxis did not influence outcome of infection. CONCLUSIONS: The meta-analysis showed that ceftriaxone is statistically superior to other antibiotics in preventing both local and remote postoperative infections.