Fluoroquinolones vs beta-lactams for empirical treatment of immunocompetent patients with skin and soft tissue infections: a meta-analysis of randomized controlled trials

Antimicrobial activity of Geranyl acetate against cell wall synthesis proteins of P. aeruginosa and S. aureus using molecular docking and simulation

Incidences of Methicillin-Resistant Staphylococcus aureus and Multi-Drug Resistant Pseudomonas aeruginosa causing skin and soft tissue infections are becoming more prevalent due to repeated mutations and changes in the environment. Coriandrum sativum, a well-known Indian herbal medicinal plant, is shown to have antioxidant, antibacterial, and anti-inflammatory activity. This comparative study focuses on the molecular docking (PyRx v0.9.8) of ligand binding domains of WbpE Aminotransferase involved in O-antigen assembly in Pseudomonas aeruginosa (3NU7) and Beta-Lactamase found in Staphylococcus aureus (1BLC) with selected phytocompounds of Coriandrum sativum along with a known binder and a clinical reference drug. This was followed by molecular dynamics simulation studies (GROMACS v2019.4) for the docked complexes (with Geranyl acetate) with the best binding affinities (-23.4304 kJ/mol with Beta-Lactamase and -28.4512 kJ/mol with WbpE Aminotransferase) and maximum hydrogen bonds. Molecular dynamics simulation studies for both the proteins demonstrated that the complex with Geranyl acetate showed stability comparable to the complex with reference drug observed via Root Mean Square Deviation (RMSD), Root Mean Square Fluctuation (RMSF) and H-bond analyses. Changes in the secondary structural elements indicated that Geranyl acetate could possibly cause improper functioning of WbpE Aminotransferase leading to disrupted cell wall formation. Further, MM/PBSA analyses showed significant binding affinity of Geranyl acetate with WbpE Aminotransferase and Beta-Lactamase. This study aims to provide rationale for further studies of Coriandrum sativum as an antimicrobial, and to contextualise the results in the current scenario of growing antimicrobial resistance. HIGHLIGHTSPhytoconstituents present in Coriandrum sativum show significant binding affinity to the proteins in Pseudomonas aeruginosa and Staphylococcus aureus.Geranyl acetate exhibited the highest binding affinity with WbpE Aminotransferase involved in O-antigen assembly in Pseudomonas aeruginosa (PDB ID:3NU7) and Beta-Lactamase found in Staphylococcus aureus (PDB ID: 1BLC)Molecular dynamics simulation analyses show that the phytoconstituent, Geranyl acetate has an effect similar to the clinical reference drug, thus exhibiting potential antibacterial activity.Communicated by Ramaswamy H. Sarma.

Calculated initial parenteral treatment of bacterial infections: Skin and soft tissue infections

This is the ninth chapter of the guideline "Calculated Parenteral Initial Therapy of Adult Bacterial Disorders - Update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. The chapter contains the first German S2k guidelines for bacterial skin and soft tissue infections. They encompass recommendations on diagnosis and treatment of the defined entities erysipelas (caused by beta-hämolytic streptococci), limited superficial cellulitis (S. aureus), severe cellulitis, abscess, complicated skin and soft tissue infections, infections of feet in diabetic patients ("diabetic foot"), necrotizing soft tissue infection and bite injuries.

S2k guidelines for skin and soft tissue infections Excerpts from the S2k guidelines for "calculated initial parenteral treatment of bacterial infections in adults - update 2018"

These first German S2k guidelines for bacterial skin and soft tissue infections were developed as one chapter of the recommendations for "calculated initial parenteral treatment of bacterial infections" issued under the auspices of the Paul-Ehrlich Society, of which the main part is presented here. Well-calculated antibiotic therapies require precise diagnostic criteria. Erysipelas is defined as non-purulent infection considered to be caused by beta-hemolytic strepto-cocci. It is diagnosed clinically by its bright-red erythema and early fever or chills at disease onset. Penicillin is the treatment of choice. Limited soft tissue infection (cellulitis) is usually caused by Staphylococcus (S.) aureus, frequently originates from chronic wounds and presents with a more violaceous-red hue and only rarely with initial fever or chills. Treatment consists of first- or second--generation cephalosporins or flucloxacillin (IV). Severe cellulitis is a purulent, partially necrotic infection which extends through tissue boundaries to fascias and requires surgical management in addition to antibiotics. Moreover, it frequently fulfills the criteria for "complicated soft tissue infections", as previously defined by the Food and Drug Administration for use in clinical trials (they include comorbidities such as uncontrolled diabetes, peripheral artery disease, neutropenia). It requires antibiotics which besides S. aureus target anaerobic and/or gramnegative bacteria. The rare so-called necrotizing skin and soft tissue infections represent a distinct entity. They are characterized by rapid, life-threatening progression due to special bacterial toxins that cause ischemic necrosis and shock and need rapid and thorough debridement in addition to appropriate antibiotics. For cutaneous abscesses the first-line treatment is adequate drainage. Additional antibiotic therapy is required only under certain circumstances (e.g., involvement of the face, hands, or anogenital region, or if drainage is somehow complicated). The present guidelines also contain consensus-based recommendations for higher doses of antibiotics than those approved or usually given in clinical trials. The goal is to deliver rational antibiotic treatment that is both effective and well-tolerated and that exerts no unnecessary selection pressure in terms of multidrug resistance.

Mining social media data to assess the risk of skin and soft tissue infections from allergen immunotherapy

BACKGROUND

Allergen immunotherapy (AIT) treatment for allergic rhinitis and asthma is used by 2.6 million Americans annually. Clinical and sterility testing studies identify no risk of contamination or infection from extracts prepared using recommended aseptic techniques, but regulatory concerns persist. Social media can be used to investigate rare adverse effects not captured by traditional studies.

OBJECTIVE

We sought to investigate large social media databases for suggestion of AIT skin and soft tissue infection (SSTI) risk and compare this risk to a comparator procedure with a sterile pharmaceutical.

METHODS

We analyzed US-restricted data from more than 10 common text-based social media platforms including Facebook, Twitter, and Reddit between 2012 and 2016. We used natural language processing (NLP) to identify posts related to AIT and, separately, influenza vaccination (comparator procedure). NLP was followed by manual review to identify posts suggesting a possible SSTI associated with either AIT or influenza vaccination. SSTI frequencies with 95% CIs were compared.

RESULTS

We identified 25,126 AIT posts, which were matched by social media platform to 25,126 influenza vaccination-related posts. NLP identified 4088 (16.3%) AIT posts that required manual review, with 6 posts (0.02%; 95% CI, 0.005%-0.043%) indicative of possible AIT-related SSTI. NLP identified 2689 (10.7%) influenza posts that required manual review, with 7 posts (0.03%; 95% CI, 0.007%-0.048%) indicative of possible influenza vaccination-related SSTI.

CONCLUSIONS

Social media data suggest that SSTI from AIT and influenza vaccination are equally rare events. Given that AIT's SSTI risk appears comparable to the risk using a sterile pharmaceutical based on social media data, current aseptic technique procedures seem safe.

Frequent bacterial skin and soft tissue infections: diagnostic signs and treatment

Skin and soft tissue infections rank among the most frequent infections worldwide. Classic erysipelas is defined as a non-purulent infection by beta-hemolytic streptococci. The typical signs are tender, warm, bright erythema with tongue-like extensions and early systemic symptoms such as fever or at least chills. Erysipelas always and best responds to penicillin. Limited soft tissue infection or limited cellulitis are the terms we have introduced for infections frequently caused by S. aureus and often originating from chronic wounds or acute trauma. Clinically, they are marked by tender, erythematous swelling which, unlike erysipelas, exhibit a darker red hue and is not always accompanied by fever or chills at onset. Severe cellulitis is a purulent, partially necrotic infection extending to the fascia, with general symptoms of infection, requiring surgical management in addition to antibiotics. It often fulfils criteria of so-called complicated soft tissue infections according to the definition of the FDA, due to their frequent association with e.g. severe diabetes mellitus, peripheral arterial occlusive disease or severe immunosuppression. In contrast, the rare necrotizing skin and soft tissue infections represent a distinct entity, characterized by rapid progression to ischemic necroses and shock due to special bacterial toxins. Limited cellulitis should be treated with cephalosporins group 1 or 2, or, when S.aureus is the isolated or highly likely causative agent, isoxazolyl-penicillins (exploiting their minimal selection pressure on other bacteria). For severe cellulitis, initial antibiotic treatment (mostly iv) includes - depending on the location - agents also active against gram-negative and/or anaerobic bacteria. (e.g. clindamycine, aminopeniclilline with inhibitors of betalaktamase, fluochinolons, cephalosporines group 4). For cutaneous abscesses, drainage presents the therapy of choice. Only under certain conditions additional antibiotic therapy is required. Adherence to the diagnostic criteria and to evidence-based or consensus-derived treatment recommendations as presented herein should allow for an antibiotic therapy with a good balance of efficacy, tolerability by patients and low selection pressure for highly resistant bacteria.

Bacterial skin and soft tissue infections in adults: A review of their epidemiology, pathogenesis, diagnosis, treatment and site of care

Skin and soft tissue infections (SSTIs) involve microbial invasion of the skin and underlying soft tissues. They have variable presentations, etiologies and severities. The challenge of SSTIs is to efficiently differentiate those cases that require immediate attention and intervention, whether medical or surgical, from those that are less severe. Approximately 7% to 10% of hospitalized patients are affected by SSTIs, and they are very common in the emergency care setting. The skin has an extremely diverse ecology of organisms that may produce infection. The clinical manifestations of SSTIs are the culmination of a two-step process involving invasion and the interaction of bacteria with host defences. The cardinal signs of SSTIs involve the features of inflammatory response, with other manifestations such as fever, rapid progression of lesions and bullae. The diagnosis of SSTIs is difficult because they may commonly masquerade as other clinical syndromes. To improve the management of SSTIs, the development of a severity stratification approach to determine site of care and appropriate empirical treatment is advantageous. The selection of antimicrobial therapy is predicated on knowledge of the potential pathogens, the instrument of entry, disease severity and clinical complications. For uncomplicated mild to moderate infections, the oral route suffices, whereas for complicated severe infections, intravenous administration of antibiotics is warranted. Recognition of the potential for resistant pathogens causing SSTIs can assist in guiding appropriate selection of antibiotic therapy.

Treatment of skin and soft tissue infections in the elderly: A review

BACKGROUND

Skin and soft tissue infections (SSTIs) have become the second most common type of infection among persons residing in long-term care facilities.

OBJECTIVE

The purpose of this article was to review the latest information on SSTIs among the elderly, including age-related changes, challenges, and treatment strategies in the era of emerging bacterial resistance.

METHODS

Relevant information was identified through a search of MEDLINE (1970-April 2010), International Pharmaceutical Abstracts (1970-April 2010), and Google Scholar using the terms skin and soft tissue infection, skin and skin structure infection, cellulitis, treatment guidelines, and elderly. Additional publications were found by searching the reference lists of the identified articles. Trials published since 1970 were selected for this review if they prospectively evaluated mostly adults (≥18 years of age), included >50 patients, and reported diagnostic criteria as well as clinical outcomes in patients treated for simple or complicated SSTIs.

RESULTS

Fifty-eight of 664 identified studies were selected and included in this review. A search of the literature did not identify any prospective clinical trials that were conducted exclusively in the elderly. Information on the treatment of SSTIs in the elderly was based solely on clinical studies that were conducted in adults in general. As recommended by the Infectious Diseases Society of America (IDSA) 2008 update, SSTIs should be suspected in elderly patients who have skin lesions and present with a decline in functional status, with or without fever. Patients who present with symptoms of systemic toxicity should be hospitalized for further evaluation. Current challenges in the management of SSTIs include the rapid emergence of community-acquired, methicillin-resistant Staphylococcus aureus (CA-MRSA), the emergence of macrolide-resistant streptococci within the past decade, and the lack of a reliable algorithm to differentiate potentially life-threatening SSTIs that require aggressive interventions and prompt hospitalization from those that can be managed in an outpatient setting. S aureus was the most common cause of SSTIs, being isolated in 42.8% (5015/11,723) of wounds, followed by streptococci. Common SSTIs in the elderly such as shingles, diabetic foot infections, infected pressure ulcers, and scabies, and their treatment were also discussed. Based on reviews of published trials, treatment of simple SSTIs generally consisted of administration of agents with activity against S aureus and Streptococcus species such as a penicillinase-resistant β-lactam, a first-generation cephalosporin, or clindamycin. Broadening of the antimicrobial spectrum to include gram-negative and anaerobic organisms should be implemented for complicated SSTIs such as diabetic foot infections and infected pressure ulcers. Local rates of MRSA, CA-MRSA, and macrolide-resistant streptococci should be considered when selecting empiric therapy.

CONCLUSIONS

A search of the literature did not identify any prospective clinical trials on the treatment of SSTIs in the elderly; therefore, it is recommended to follow treatment based on the current IDSA guidelines. More research and publications are needed to establish proper selection of antimicrobial agents, treatment strategies, and duration of therapy of SSTIs in the elderly population.

Infectious Disease Concepts and Considerations in the Diabetic Patient

Diabetic patients present their providers with unique clinical challenges when dealing with prevention and treatment of infectious diseases. By the very nature of their diabetes, these patients are at much higher risk of complications from seemingly benign infections as well as increasingly susceptible to more resistant or invasive disease. Targeted prevention where possible, regular follow-up, and early, aggressive treatment are crucial to diabetic patients’ longevity and quality of life. This review will focus on key vaccine-preventable issues as well as management of common conditions such as urinary tract infection and skin and soft tissue infection often seen in diabetic patients.

Respiratory fluoroquinolones for the treatment of community-acquired pneumonia: a meta-analysis of randomized controlled trials

BACKGROUND

We investigated whether the use of respiratory fluoroquinolones was associated with better clinical outcomes compared with the use of macrolides and beta- lactams among adults with pneumonia.

METHODS

We searched PubMed, Current Contents, Scopus, EMBASE, ClinicalTrials.gov and Cochrane with no language restrictions. Two reviewers independently extracted data from published trials that compared fluoroquinolones (levofloxacin, moxifloxacin, gemifloxacin) with macrolides or beta-lactams or both. A meta-analysis was performed with the clinical outcomes of mortality, treatment success and adverse outcomes.

RESULTS

We included 23 trials in our meta-analysis. There was no difference in mortality among patients who received fluoroquinolones or the comparator antibiotics (OR 0.85, 95% CI 0.65-1.12). Pneumonia resolved in more patients who received fluoroquinolones compared with the comparator antibiotics for the included outcomes in the intention-to-treat population (OR 1.17, 95% CI 1.00-1.36), clinically evaluable population (OR 1.26, 95% CI 1.06-1.50) and the microbiologically assessed population (OR 1.67, 95% CI 1.28-2.20). Fluoroquinolones were more effective than a combination of beta-lactam and macrolide (OR 1.39, 95% CI 1.02-1.90). They were also more effective for patients with severe pneumonia (OR 1.84, 95% CI 1.02-3.29), those who required admission to hospital (OR = 1.30, 95% CI 1.04-1.61) and those who required intravenous therapy (OR = 1.44, 15% CI 1.13-1.85). Fluoroquinolones were more effective than beta-lactam and macrolide in open-label trials (OR = 1.35, 95% CI 1.08-1.69) but not in blinded randomized controlled trials (OR = 1.13, 95% CI 0.85-1.50).

INTERPRETATION

Fluoroquinolones were associated with higher success of treatment for severe forms of pneumonia; however, a benefit in mortality was not evident. A randomized controlled trial that includes patients with severe pneumonia with or without bacteremia is needed.

Efficacy of oral beta-lactam versus non-beta-lactam treatment of uncomplicated cellulitis

BACKGROUND

Preferred therapy for purulent skin and soft tissue infections is incision and drainage, but many infections cannot be drained. Empiric therapies for these infections are ill-defined in the era of community-acquired methicillin-resistant Staphylococcus aureus.

METHODS

A multicenter retrospective cohort study of outpatients treated for cellulitis was conducted to compare clinical failure rates of oral beta-lactam and non-beta-lactam treatments. Exclusion criteria included purulent infection requiring incision and drainage, complicated skin and soft tissue infection, chronic ulceration, and intravenous antibiotics. Failure rates were compared using logistic regression to adjust for both covariates associated with failure and a propensity score for beta-lactam treatment.

RESULTS

Of 2977 patients, 861 met inclusion criteria and were classified by treatment: beta-lactam (n = 631) or non-beta-lactam therapy (n = 230). Failure rates were 14.7% versus 17.0% (odds ratio [OR] 0.85, 95% confidence interval [CI], 0.56-1.31) for beta-lactam and non-beta-lactam therapy, respectively. Failure was associated with: age (P = .02), acute symptom severity (P = .03), animal bites (P = .03), Charlson score > 3 (P = .02), and histamine-2 receptor antagonist use (P = .09). Relative efficacy of beta-lactam therapy was greater after adjustment for factors associated with failure but remained statistically insignificant (adjusted OR 0.81, 95% CI, 0.53-1.24); adjusted including propensity score covariate (OR 0.71, 95% CI, 0.45-1.13). Discontinuation due to adverse effects differed between beta-lactam (0.5%) and non-beta-lactam (2.2%) therapies (P = .04).

CONCLUSION

There was no significant difference in clinical failure between beta-lactam and non-beta-lactam antibiotics for the treatment of uncomplicated cellulitis. Increased discontinuation due to adverse events with non-beta-lactam therapy was observed.

Fluoroquinolones compared with beta-lactam antibiotics for the treatment of acute bacterial sinusitis: a meta-analysis of randomized controlled trials

BACKGROUND

The presumed superiority of newer fluoroquinolones for the treatment of acute bacterial sinusitis is based on laboratory data but has not yet been established on clinical grounds.

METHODS

We performed a meta-analysis of randomized controlled trials comparing the effectiveness and safety of fluoroquinolones and beta-lactams in acute bacterial sinusitis.

RESULTS

We identified 8 randomized controlled trials investigating the newer "respiratory" fluoroquinolones moxifloxacin, levofloxacin and gatifloxacin. In the primary effectiveness analysis involving 2133 intention-to-treat patients from 5 randomized controlled trials, the extent of clinical cure and improvement did not differ between fluoroquinolones and beta-lactams (odds ratio [OR] 1.09, 95% confidence interval [CI] 0.85-1.39) at the test-of-cure assessment, which varied from 10 to 31 days after the start of treatment. Fluoroquinolones were associated with an increased chance of clinical success among the clinically evaluable patients in all of the randomized controlled trials (OR 1.29, 95% CI 1.03-1.63) and in 4 blinded randomized controlled trials (OR 1.45, 95% CI 1.05-2.00). There was no statistically significant difference between fluoroquinolones and amoxicillin-clavulanate (OR 1.24, 95% CI 0.93-1.65). Eradication or presumed eradication of the pathogens isolated before treatment was more likely with fluoroquinolone treatment than with beta-lactam treatment (OR 2.11, 95% CI 1.09-4.08). In the primary safety analysis, adverse events did not differ between treatments (OR 1.17, 95% CI 0.86-1.59). However, more adverse events occurred with fluoroquinolone use than with beta-lactam use in 2 blinded randomized controlled trials. The associations described here were generally consistent when we included 3 additional studies involving other fluoroquinolones (ciprofloxacin and sparfloxacin) in the analysis.

INTERPRETATION

In the treatment of acute bacterial sinusitis, newer fluoroquinolones conferred no benefit over beta-lactam antibiotics. The use of fluoroquinolones as first-line therapy cannot be endorsed.