Skin and Soft Tissue Infections: The New Surgical Infection Society Guidelines

LysSYL-Loaded pH-Switchable Self-Assembling Peptide Hydrogels Promote Methicillin-Resistant Staphylococcus Aureus Elimination and Wound Healing

Staphylococcus aureus (S. aureus), especially methicillin-resistant S. aureus (MRSA), causes wound infections, whose treatment remains a clinical challenge. Bacterium-infected wounds often create acidic niches with a pH 4.5-6.5. Endolysin LysSYL, which is derived from phage SYL, shows promise as an antistaphylococcal agent. However, endolysins generally exhibit instability and possess low bioavailability in acidic microenvironments. Here, an array of self-assembling peptides is designed, and peptide L5 is screened out based on its gel formation property and bioavailability. L5 exerted a pH-switchable antimicrobial effect (pH 5.5) and formed biocompatible hydrogels at neutral pH (pH 7.4). The LysSYL-loaded L5 can assemble L5@LysSYL hydrogels, increase thermal stability, and exhibit the slow-release effect of LysSYL. Effective elimination of S. aureus is achieved by L5@LysSYL through bacterial membrane disruption and cell separation inhibition. Moreover, L5@LysSYL hydrogels exhibit great potential in promoting wound healing in a mouse wound model infected by MRSA. Furthermore, L5@LysSYL hydrogels are safe and can decrease the cytokine levels and increase the number of key factors for vessel formation, which contribute to wound healing. Overall, the self-assembling L5@LysSYL can effectively clean MRSA and promote wound healing, which suggests its potential as a pH-sensitive wound dressing for the management of wound infections.

Analysis of host-pathogen gene association networks reveals patient-specific response to streptococcal and polymicrobial necrotising soft tissue infections

BACKGROUND

Necrotising soft tissue infections (NSTIs) are rapidly progressing bacterial infections usually caused by either several pathogens in unison (polymicrobial infections) or Streptococcus pyogenes (mono-microbial infection). These infections are rare and are associated with high mortality rates. However, the underlying pathogenic mechanisms in this heterogeneous group remain elusive.

METHODS

In this study, we built interactomes at both the population and individual levels consisting of host-pathogen interactions inferred from dual RNA-Seq gene transcriptomic profiles of the biopsies from NSTI patients.

RESULTS

NSTI type-specific responses in the host were uncovered. The S. pyogenes mono-microbial subnetwork was enriched with host genes annotated with involved in cytokine production and regulation of response to stress. The polymicrobial network consisted of several significant associations between different species (S. pyogenes, Porphyromonas asaccharolytica and Escherichia coli) and host genes. The host genes associated with S. pyogenes in this subnetwork were characterised by cellular response to cytokines. We further found several virulence factors including hyaluronan synthase, Sic1, Isp, SagF, SagG, ScfAB-operon, Fba and genes upstream and downstream of EndoS along with bacterial housekeeping genes interacting with the human stress and immune response in various subnetworks between host and pathogen.

CONCLUSIONS

At the population level, we found aetiology-dependent responses showing the potential modes of entry and immune evasion strategies employed by S. pyogenes, congruent with general cellular processes such as differentiation and proliferation. After stratifying the patients based on the subject-specific networks to study the patient-specific response, we observed different patient groups with different collagens, cytoskeleton and actin monomers in association with virulence factors, immunogenic proteins and housekeeping genes which we utilised to postulate differing modes of entry and immune evasion for different bacteria in relationship to the patients' phenotype.

Association of sarcopenia with a higher risk of infection in patients with type 2 diabetes

AIMS

This study aimed to determine whether patients with type 2 diabetes and sarcopenia had a higher risk of infection.

STUDY DESIGNS

A cross-sectional study and a follow-up study were performed.

METHOD

A total of 2562 patients were enrolled and assessed for body composition and infection status. They were classified into four groups according to body fat (BF) and muscle mass index (ASMI): obese, sarcopenic, sarcopenic obese, and normal. Among these, 275 patients were followed for a median follow-up period of 1.84 years to evaluate the relationship of changes in skeletal muscle with infection status.

RESULTS

The sarcopenic and sarcopenic obese groups showed a higher risk of infection, an increase by 49.6% (OR = 1.496, 95% CI 1.102-2.031) and 42.4% (OR = 1.424, 95% CI 1.031-1.967) compared with the normal group, and also had a higher risk of respiratory infection, an increase by 56.0% (OR = 1.560, 95% CI 1.084-2.246) and 57.4% (OR = 1.574, 95% CI 1.080-2.293), respectively. Patients with the increased ASMI (OR = 0.079, 95% CI 0.021-0.298) represented a lower risk of infection than those with the decreased ASMI. Even a minor change (OR = 0.125, 95% CI 0.041-0.378) against age was beneficial to lowering the risk of infection. However, no association was found in the changes of body mass index and BF with infection status.

CONCLUSIONS

Sarcopenia, especially in patients with diabetes who are also obese, increases the risk of infection. Maintaining or improving muscle mass is expected to reduce infections.

Cotrimoxazole and clindamycin in skin and soft tissue infections

PURPOSE OF REVIEW

The aim of this study was to present recent microbiological, experimental, clinical and tolerance data for cotrimoxazole and clindamycin in the specific field of skin and soft tissue infections (SSTIs).

RECENT FINDINGS

Staphylococcus aureus and streptococci remain the leading cause of SSTIs. Cotrimoxazole is a good anti-Gram-positive agent with preserved activity against methicillin-susceptible and methicillin-resistant S. aureus (MRSA) and streptococci. Although clindamycin has good methicillin-susceptible S. aureus activity, a growing number of resistant MRSA and streptococci have been reported. Strong experimental data support the antitoxin activity of clindamycin, but clinical observations remain scarce. Several recent randomized trials involving cotrimoxazole and/or clindamycin demonstrate the efficacy and tolerance of both drugs. The oral formulation of both drugs may facilitate the implementation of early switch and early discharge protocols in clinical practice.

SUMMARY

Recent publications demonstrate that cotrimoxazole and clindamycin remain reliable and realistic therapeutic approaches for SSTIs.

Wound Infections from Taiwan Cobra (Naja atra) Bites: Determining Bacteriology, Antibiotic Susceptibility, and the Use of Antibiotics-A Cobra BITE Study

Wound necrosis and secondary infection are common complications after Naja atra bites. Clinical tools to evaluate the infection risk after Taiwan cobra bites are lacking. In this Cobra BITE study, we investigated the prevalence of wound infection, bacteriology, and corresponding antibiotic usage in patients presenting with Taiwan cobra snakebites. Patients with wound infection lacking tissue necrosis were included in developing Cobra BITE score utilizing univariate and multiple logistic regression, as patients with wound necrosis require antibiotics for infection treatment. 8,295,497 emergency department visits occurred in the span of this study, with 195 of those patients being diagnosed as having cobra bites. Of these patients, 23 had wound necrosis, and 30 had wound infection, resulting in a wound infection rate of 27.2% (53/195). Enterococcus faecalis and Morganella morganii were the main bacteria identified in the culture report regardless of whether patients’ wounds had necrosis. As per our Cobra BITE score, the three factors predicting secondary wound infection after cobra bites are hospital admission, a white blood cell count (in 103/µL) × by neu-trophil-lymphocyte ratio value of ≥114.23, and the use of antivenin medication. The area under the receiver operating characteristic curve for the Cobra BITE score system was 0.88; ideal sensitivity and specificity were 0.89 and 0.76. This scoring system enables the assessment of wound infections after N. atra bites, and it could be modified and improved in the future for other Naja spp. bites.

Wound Infections of Snakebites from the Venomous Protobothrops mucrosquamatus and Viridovipera stejnegeri in Taiwan: Bacteriology, Antibiotic Susceptibility, and Predicting the Need for Antibiotics-A BITE Study

Snakebites from Taiwan habus (Protobothrops mucrosquamatus) and green bamboo vipers (Viridovipera stejnegeri) account for two-thirds of all venomous snakebites in Taiwan. While there has been ongoing optimization of antivenin therapy, the proper management of superimposed bacterial wound infections is not well studied. In this Bacteriology of Infections in Taiwanese snake Envenomation (BITE) study, we investigated the prevalence of wound infection, bacteriology, and corresponding antibiotic usage in patients presenting with snakebites from these two snakes. We further developed a BITE score to evaluate the probability of wound infections and guide antibiotic usage in this patient population. All snakebite victims who presented to the emergency departments of seven training and research hospitals and received at least one vial of freeze-dried hemorrhagic antivenin between January 2001 and January 2017 were identified. Patient biodata, laboratory investigation results, and treatment modalities were retrieved. We developed our BITE score via univariate and multiple logistic regression analyses. The receiver operating characteristic (ROC) curve was plotted to evaluate the predictive performance of the BITE score. Out of 8,295,497 emergency department visits, 726 patients presented with snakebites from a Taiwan habu or a green bamboo viper. The wound infection rate was 22.45%, with seven positive wound cultures, including six polymicrobial infections. Morganella morganii, Enterococcus spp., Bacteroides fragilis, and Aeromonas hydrophila were most frequently cultured. There were no positive blood cultures. A total of 33.0% (n = 106) of snakebite patients who received prophylactic antibiotics nevertheless developed wound infections, while 44.8% (n = 73) of wound infection patients were satisfactorily treated with one of the following antibiotics: amoxicillin/clavulanic acid, oxacillin, cefazolin, and ampicillin/sulbactam. With the addition of gentamicin, the success of antibiotic therapy increased by up to 66.54%. The prognostic factors for the secondary bacterial infection of snakebites were white blood cell counts, the neutrophil lymphocyte ratio, and the need for hospital admission. The area under the ROC curve for the BITE score was 0.839. At the optimal cut-off point of 5, the BITE score had a 79.58% accuracy, 82.31% sensitivity, and 79.71% specificity when predicting infection in snakebite patients. Our BITE score may help with antibiotic stewardship by guiding appropriate antibiotic use in patients presenting with snakebites. It may also be employed in further studies into antibiotic prophylaxis in snakebite patients for the prevention of superimposed bacterial wound infections.

Early switch/early discharge opportunities for hospitalized patients with methicillin resistant Staphylococcus aureus complicated skin and soft tissue infections: Saudi Arabia and United Arab Emirates

OBJECTIVES

To describe opportunities for early switch (ES) from intravenous (IV) to oral (PO) antibiotics and early discharge (ED) of patients hospitalized in the Kingdom of Saudi Arabia (KSA) and the United Arab Emirates (UAE) with methicillin-resistant Staphylococcus aureus (MRSA) complicated skin and soft tissue infections (cSSTIs).

METHODS

This retrospective medical chart review study enrolled physicians from 16 KSA and UAE sites to collect data for 107 MRSA cSSTI patients.

RESULTS

Actual length of MRSA-active treatment was 13.3±9.3 mean days in KSA and 11.2±3.9 mean days in UAE, with a mean of 11.8±9.3 days of MRSA-targeted IV therapy in KSA and 10.7±4.3 days in UAE. 12.5% in KSA met ES criteria and potentially could have discontinued IV therapy 4.0±2.9 days sooner; 44.0% in UAE could have discontinued 6.6±3.6 days sooner. Patients were hospitalized for a mean 28.6±45.0 days in KSA and 13.1±5.9 days in UAE. 25.0% in KSA and 48.0% in UAE met ED criteria and potentially could have been discharged 6.1±8.0 days earlier in KSA and 7.9±5.0 days earlier in UAE.

CONCLUSIONS

A significant proportion of patients hospitalized for MRSA cSSTI could be eligible for ES or ED opportunities, resulting in potential for reductions in IV and bed days.

Aquatic Orthopaedic Injuries

Extremity injuries sustained in aquatic environments require unique considerations compared with injuries sustained on land. Knowledge of these considerations is becoming more important as aquatic recreational activities increase in popularity. Aquatic injuries may occur through mechanical contact with a variety of different objects or surfaces, such as a recreational device or watercraft part, or may occur through contact with marine animals. Marine animal injuries can be further categorized into bites, stings, or blunt contact, as well as venomous or nonvenomous, distinctions that should be used to guide clinical management. Numerous instances of retained foreign bodies after marine animal stings exist, which can result in infection and prolonged envenomization; thus, radiographic examination should be routinely performed in aquatic sting injuries to prevent these harmful sequelae. Any aquatic injury resulting in an open wound has an increased risk for infection, and prophylactic antibiotics must be given with consideration for the unique microbiologic flora of the aquatic environment.

Skin and soft tissue infections after breast surgery

PURPOSE OF REVIEW

Breast surgery is considered a clean surgical procedure; nevertheless, infection rates are often higher than those reported after other similarly considered clean surgeries (e.g., thyroid, hernia). Acute bacterial skin and soft tissue infections, mostly surgical site infections and implant-associated infections are commonest events that could complicate postoperative care.

RECENT FINDINGS

Risk of infection is closely related to surgery procedure itself and patients host factors. Gram-positive bacteria with pattern of antimicrobial resistance are increasingly isolated and before today less frequent causes such as gram negative and mycobacteria infections. Impact of postoperative complications is underestimated and lacking an appropriate care and education for local and systemic management.

SUMMARY

We report the current evidence on the management of infections after breast surgery. New drugs options for methicillin-resistant Staphylococcus aureus and other gram positive should have a place in this setting. Stewardship activities aiming at reducing infections risks with the correct considerations of host, microbiological and surgical risk factors.

Management of complicated skin and soft tissue infections with a special focus on the role of newer antibiotics

Complicated skin and soft tissue infections (cSSTIs) represent the severe form of infectious disease that involves deeper soft tissues. Involvement of methicillin-resistant Staphylococcus aureus (MRSA) further complicates cSSTI with increased hospitalization, health care costs, and overall mortality. Various international guidelines provide recommendations on the management of cSSTIs, with the inclusion of newer antibiotics. This literature-based review discusses the overall management of cSSTI, including appropriate use of antibiotics in clinical practice. Successful treatment of cSSTIs starts with early and precise diagnosis, including identification of causative pathogen and its load, determination of infection severity, associated complications, and risk factors. The current standard-of-care for cSSTIs involves incision, drainage, surgical debridement, broad-spectrum antibiotic therapy, and supportive care. In recent years, the emergence of newer antibiotics (eg, ceftaroline, tigecycline, daptomycin, linezolid, etc) has provided clinicians wider options of antimicrobial therapy. Selection of antibiotics should be based on the drug characteristics, effectiveness, safety, and treatment costs, alongside other aspects such as host factors and local multidrug resistance rates. However, larger studies on newer antibiotics are warranted to refine the decision making on the appropriate antimicrobial therapy. Local Antimicrobial Stewardship Program strategies in health care settings could guide clinicians for early initiation of specific treatments to combat region-specific antimicrobial resistance, minimize adverse effects, and to improve outcomes such as reduction in Clostridium difficile infections. These strategies involving iv-to-oral switch, de-escalation to narrow-spectrum antibiotics, and dose optimization have an impact on the overall improvement of cSSTI therapy outcomes, especially in countries like Singapore that has a high disease burden.

Early Enteral Nutrition is Associated with Reduced Morbidity in Critically Ill Soft Tissue Patients

Soft tissue diseases including necrotizing soft tissue infections are associated with high mortality and morbidity with hospital-acquired infection rates up to 76 per cent. Critically ill patients with soft tissue infections have increased metabolic requirements; however, the effect of early nutrition on inhospital morbidity including nosocomial infection rates remains unclear. We hypothesized that enteral nutrition within 48 hours of intensive care unit admission would be associated with fewer hospital-acquired infections. We conducted a retrospective review of patients with soft tissue infection requiring intensive care unit admission for >72 hours from January 2013 through December 2014 to a high-volume, dedicated soft tissue service. Variables were compared using chisquared, Student's t test, linear regression, and binary logistic regression analysis. Eighty-five patients met inclusion criteria; 80 per cent started enteral nutrition within 48 hours. Twenty-six per cent had a hospital-acquired infection postadmission requiring treatment. Patients started on enteral nutrition within 48 hours had fewer ventilator days (mean 5 vs 12) and shorter hospital length of stay (mean 18 vs 40 days) when adjusted for age, gender, and confounding variables present on admission. Patients receiving early nutrition also had fewer hospital-acquired infections (18 vs 59%) when adjusted for confounding factors (aOR 0.15, P = 0.045). No significant difference in mortality (13.2% early vs 5.9% late, P = 0.4) or for inhospital morbidity when evaluating percentage of goal calories or protein received or time to goal tube feed rate was found. Early enteral feeding is associated with reduced inhospital morbidity in critically ill soft tissue patients, including fewer hospital-acquired infections and ventilator days, and shorter total length of stay.

Impact of Intravenous Immunoglobulin on Survival in Necrotizing Fasciitis With Vasopressor-Dependent Shock: A Propensity Score-Matched Analysis From 130 US Hospitals

Background

Shock frequently complicates necrotizing fasciitis (NF) caused by group A Streptococcus (GAS) or Staphylococcus aureus. Intravenous immunoglobulin (IVIG) is sometimes administered for presumptive toxic shock syndrome (TSS), but its frequency of use and efficacy are unclear.

Methods

Adult patients with NF and vasopressor-dependent shock undergoing surgical debridement from 2010 to 2014 were identified at 130 US hospitals. IVIG cases were propensity-matched and risk-adjusted. The primary outcome was in-hospital mortality and the secondary outcome was median length of stay (LOS).

Results

Of 4127 cases of debrided NF with shock at 121 centers, only 164 patients (4%) at 61 centers received IVIG. IVIG subjects were younger with lower comorbidity indices, but higher illness severity. Clindamycin and vasopressor intensity were higher among IVIG cases, as was coding for TSS and GAS. In-hospital mortality did not differ between matched IVIG and non-IVIG groups (crude mortality, 27.3% vs 23.6%; adjusted odds ratio, 1.00 [95% confidence interval, .55-1.83]; P = .99). Early IVIG (≤2 days) did not alter this effect (P = .99). Among patients coded for TSS, GAS, and/or S. aureus, IVIG use was still unusual (59/868 [6.8%]) and lacked benefit (P = .63). Median LOS was similar between IVIG and non-IVIG groups (26 [13-49] vs 26 [11-43]; P = .84). Positive predictive values for identifying true NF and debridement among IVIG cases using our algorithms were 97% and 89%, respectively, based on records review at 4 hospitals.

Conclusions

Adjunctive IVIG was administered infrequently in NF with shock and had no apparent impact on mortality or hospital LOS beyond that achieved with debridement and antibiotics.

Management of acute bacterial skin and skin structure infections with a focus on patients at high risk of treatment failure

Over the last 25 years, the terminology of skin and soft tissue infections, as well as their classification for optimal management of patients, has changed. The so-called and recently introduced term 'acute bacterial skin and skin structure infections' (ABSSSIs), a cluster of fairly common types of infection, including abscesses, cellulitis, and wound infections, require an immediate effective antibacterial treatment as part of a timely and cautious management. The extreme level of resistance globally to many antibiotic drugs in the prevalent causative pathogens, the presence of risk factors of treatment failure, and the high epidemic of comorbidities (e.g. diabetes and obesity) make the appropriate selection of the antibiotic for physicians highly challenging. The selection of antibiotics is primarily empirical for ABSSSI patients which subsequently can be adjusted based on culture results, although rarely available in outpatient management. There is substantial evidence suggesting that inappropriate antibiotic treatment is given to approximately 20-25% of patients, potentially prolonging their hospital stay and increasing the risk of morbidity and mortality. The current review paper discusses the concerns related to the management of ABSSSI and the patient types who are most vulnerable to poor outcomes. It also highlights the key management time-points that treating physicians and surgeons must be aware of in order to achieve clinical success and to discharge patients from the hospital as early as possible.

Fungal Infections Increase the Mortality Rate Three-Fold in Necrotizing Soft-Tissue Infections

BACKGROUND

Necrotizing soft-tissue infections (NSTIs) result in significant morbidity and mortality rates, with as many as 76% of patients dying during their index admission. Published data suggest NSTIs rarely involve fungal infections in immunocompetent patients. However, because of the recent recognition of fungal infections in our population, we hypothesized that such infections frequently complicate NSTIs and are associated with higher morbidity and mortality rates.

METHODS

A prospectively maintained Acute and Critical Care Surgery (ACCS) database spanning 2008-2015 and including more than 7,000 patients was queried for patients with NSTIs. Microbiologic data, demographics, and clinical outcomes were abstracted. Risk factors and outcomes associated with NSTI with positive intra-operative fungal cultures were determined. Frequencies were compared by χ² and continuous variables by the Student t-test using SPSS. Because the study included only archived data, no patient permission was needed.

RESULTS

A total of 230 patients were found to have NSTIs; 197 had intra-operative cultures, and 21 (10.7%) of these were positive for fungi. Fungal infection was more common in women, patients with higher body mass index (BMI), and patients who had had prior abdominal procedures. There were no significant differences in demographics, co-morbidities, or site of infection. The majority of patients (85.7%) had mixed bacterial and fungal infections; in the remaining patients, fungi were the only species isolated. Most fungal cultures were collected within 48 h of hospital admission, suggesting that the infections were not hospital acquired. Patients with positive fungal cultures required two more surgical interventions and had a three-fold greater mortality rate than patients without fungal infections.

CONCLUSIONS

This is the largest series to date describing the impact of fungal infection in NSTIs. Our data demonstrate a three-fold increase in the mortality rate and the need for two additional operations. Consideration should be given to starting patients on empiric anti-fungal therapy in certain circumstances.

Current and future trends in antibiotic therapy of acute bacterial skin and skin-structure infections

In 2013 the US Food and Drug Administration (FDA) issued recommendations and guidance on developing drugs for treatment of skin infection using a new definition of acute bacterial skin and skin-structure infection (ABSSSI). The new classification includes cellulitis, erysipelas, major skin abscesses and wound infection with a considerable extension of skin involvement, clearly referring to a severe subset of skin infections. The main goal of the FDA was to better identify specific infections where the advantages of a new antibiotic could be precisely estimated through quantifiable parameters, such as improvement of the lesion size and of systemic signs of infection. Before the spread and diffusion of methicillin-resistant Staphylococcus aureus (MRSA) in skin infections, antibiotic therapy was relatively straightforward. Using an empiric approach, a β-lactam was the preferred therapy and cultures from patients were rarely obtained. With the emergence of MRSA in the community setting, initial ABSSSI management has been changed and readdressed. Dalbavancin, oritavancin and tedizolid are new drugs, approved or in development for ABSSSI treatment, that also proved to be efficient against MRSA. Dalbavancin and oritavancin have a long half-life and can be dosed less frequently. This in turn makes it possible to treat patients with ABSSSI in an outpatient setting, avoiding hospitalization or potentially allowing earlier discharge, without compromising efficacy. In conclusion, characteristics of long-acting antibiotics could represent an opportunity for the management of ABSSSI and could profoundly modify the management of these infections by reducing or in some cases eliminating both costs and risks of hospitalization.

Current guidelines and recommendations for the management of skin and soft tissue infections

PURPOSE OF REVIEW

The incidence of severe skin and soft tissue infections (SSTIs) has significantly increased over the last years. In addition, major ecological changes have been reported with the emergence of community-acquired methicillin-resistant Staphylococcus aureus (MRSA), involved in a large proportion of these cases. A large number of expert opinions, guidelines, and recommendations for the management of SSTIs have been published over the last decade. The purpose of this review is to compare these guidelines.

RECENT FINDINGS

A total of six official publications have presented recommendations for the management of SSTIs. During the same period, other guidelines for the management of MRSA infections have also been published, including some recommendations for SSTIs.

SUMMARY

The applicability of the guidelines is questionable in many ways. The distinction between necrotizing/nonnecrotizing infections is valuable but difficult to apply prior to surgical management. The prescribers should choose a pragmatic approach to empirical antibiotic therapy, taking into account the patient's initial severity, the extent of infection and risk factors for resistant microorganisms essentially related to healthcare-associated circumstances.

Skin and soft-tissue infections: a critical review and the role of telavancin in their treatment

Skin and soft-tissue infections (SSTIs) are an important cause of morbidity and mortality among hospitalized patients and a major therapeutic challenge for clinicians. Although uncomplicated SSTIs are managed successfully on an outpatient basis, more serious infections extending to the subcutaneous tissue, fascia, or muscle require complex management. Early diagnosis, selection of appropriate antimicrobials, and timely surgical intervention are key to successful treatment. Surgical-site infections, an important category of SSTI, occur in approximately half a million patients in North America annually. SSTIs are also a potential source for life-threatening bacteremia and metastatic abscesses. Gram-positive organisms, such as Staphylococcus aureus and Streptococcus pyogenes, are the dominant organisms isolated early in the infectious process, whereas gram-negative organisms are found in chronic wounds. Methicillin-resistant S. aureus (MRSA) is a potential bloodstream invader that requires aggressive antimicrobial treatment and surgery. Recent concerns regarding vancomycin activity include heteroresistance in MRSA and increase in the minimum inhibitory concentrations (>1 or 2 µg/mL); however, alternative agents, such as telavancin, daptomycin, linezolid, ceftaroline, dalbavancin, oritavancin, and tedizolid, are now available for the treatment of severe MRSA infections. Here, we present a review of the epidemiology, etiology, and available treatment options for the management of SSTIs.

Multidrug-Resistant Gram-Negative Bacterial Infections in the Hospital Setting: Overview, Implications for Clinical Practice, and Emerging Treatment Options

The increasing prevalence of infections due to multidrug-resistant (MDR) gram-negative bacteria constitutes a serious threat to global public health due to the limited treatment options available and the historically slow pace of development of new antimicrobial agents. Infections due to MDR strains are associated with increased morbidity and mortality and prolonged hospitalization, which translates to a significant burden on healthcare systems. In particular, MDR strains of Enterobacteriaceae (especially Klebsiella pneumoniae and Escherichia coli), Pseudomonas aeruginosa, and Acinetobacter baumannii have emerged as particularly serious concerns. In the United States, MDR strains of these organisms have been reported from hospitals throughout the country and are not limited to a small subset of hospitals. Factors that have contributed to the persistence and spread of MDR gram-negative bacteria include the following: overuse of existing antimicrobial agents, which has led to the development of adaptive resistance mechanisms by bacteria; a lack of good antimicrobial stewardship such that use of multiple broad-spectrum agents has helped perpetuate the cycle of increasing resistance; and a lack of good infection control practices. The rising prevalence of infections due to MDR gram-negative bacteria presents a significant dilemma in selecting empiric antimicrobial therapy in seriously ill hospitalized patients. A prudent initial strategy is to initiate treatment with a broad-spectrum regimen pending the availability of microbiological results allowing for targeted or narrowing of therapy. Empiric therapy with newer agents that exhibit good activity against MDR gram-negative bacterial strains such as tigecycline, ceftolozane-tazobactam, ceftazidime-avibactam, and others in the development pipeline offer promising alternatives to existing agents.

Application of a uniform anatomic grading system to measure disease severity in eight emergency general surgical illnesses

BACKGROUND

Emergent general surgical diseases encompass a broad spectrum of anatomy and pathophysiology, creating challenges for outcomes assessment, research, and surgical training. The goal of this study was to measure anatomic disease severity for eight emergent general surgical diseases using the uniform grading system of the American Association for the Surgery of Trauma (AAST).

METHODS

The Committee on Patient Assessment and Outcomes of AAST applied the previously developed uniform grading system to eight emergent general surgical diseases using a consensus of experts. It was then reviewed and approved by the Board of Managers of AAST.

RESULTS

Severity grades for eight commonly encountered emergent general surgical conditions were created: breast abscess, esophageal perforation, infectious colitis, pelvic inflammatory disease, perirectal abscess, pleural space infections, soft tissue infections, and surgical site infections. The range of grades from I through V, reflect progression from mild disease, limited to within the organ itself, to widespread severe disease.

CONCLUSION

This article provides a uniform grading system for measuring anatomic severity of eight emergent general surgical diseases. Consistent adoption of these grades could improve standardization for quality assurance, outcomes research, and surgical training.

Necrotizing soft tissue infections

Necrotizing soft tissue infections (NSTIs) are infrequent yet highly lethal infections, and a high index of suspicion is required for early diagnosis. Diagnosing NSTIs early can be challenging, and knowledge of the available tools is essential to provide appropriate treatment. The mainstay of treatment is early and complete surgical debridement combined with antimicrobial therapy, close monitoring with further debridement as needed, and physiologic support. Mortality continues to be high, and delayed surgical treatment is the most important risk factor. For the long-term recovery of patients with NSTI, providing early physiologic and nutritional support and physical rehabilitation is essential.

Ceftaroline fosamil use in hospitalized patients with acute bacterial skin and skin structure infections: Budget impact analysis from a hospital perspective

PURPOSE

The budgetary impact of adding ceftaroline fosamil to a hospital formulary for the treatment of acute bacterial skin and skin structure infections (ABSSSIs) was evaluated.

METHODS

A three-year hospital budget impact model was constructed with three initial treatment options for ABSSSIs: ceftaroline fosamil, vancomycin plus aztreonam, and other vancomycin-containing regimens. The target population was hospitalized adult patients with an ABSSSI. Clinical cure rates with initial treatment were assumed to be similar to those from ceftaroline fosamil clinical trials. Patients who did not respond to initial treatment were assumed to be treated successfully with second-line antimicrobial therapy. Length of stay and cost per hospital day (by success or failure with initial treatment) were estimated based on a large database from more than 100 U.S. hospitals. Other model inputs included the annual number of ABSSSI admissions, projected annual case growth rate, proportion of ABSSSI target population receiving vancomycin-containing regimen, expected proportion of ABSSSI target population to be treated with ceftaroline fosamil, drug acquisition cost, cost of antibiotic administration, and cost of vancomycin monitoring. Sensitivity analysis using 95% confidence limits of clinical cure rates was also performed.

RESULTS

The estimated total cost of care for treating a patient with an ABSSSI was $395 lower with ceftaroline fosamil ($15,087 versus $15,482) compared with vancomycin plus aztreonam and $72 lower ($15,087 versus $15,159) compared with other vancomycin-containing regimens.

CONCLUSION

Model estimates indicated that adding ceftaroline fosamil to the hospital formulary would not have a negative effect on a hospital's budget for ABSSSI treatment.