The importance of source control in the management of severe skin and soft tissue infections

The Etiology, Antibiotic Therapy and Outcomes of Bacteremic Skin and Soft-Tissue Infections in Onco-Hematological Patients

OBJECTIVES

to assess the current epidemiology, antibiotic therapy and outcomes of onco- hematological patients with bacteremic skin and soft-tissue infections (SSTIs), and to identify the risk factors for Gram-negative bacilli (GNB) infection and for early and overall mortality.

METHODS

episodes of bacteremic SSTIs occurring in cancer patients at two hospitals were prospectively recorded and retrospectively analyzed.

RESULTS

Of 164 episodes of bacteremic SSTIs, 53% occurred in patients with solid tumors and 47% with hematological malignancies. GNB represented 45.5% of all episodes, led by Pseudomonas aeruginosa (37.8%). Multidrug resistance rate was 16%. Inadequate empirical antibiotic therapy (IEAT) occurred in 17.7% of episodes, rising to 34.6% in those due to resistant bacteria. Independent risk factors for GNB infection were corticosteroid therapy and skin necrosis. Early and overall case-fatality rates were 12% and 21%, respectively. Risk factors for early mortality were older age, septic shock, and IEAT, and for overall mortality were older age, septic shock and resistant bacteria.

CONCLUSIONS

GNB bacteremic SSTI was common, particularly if corticosteroid therapy or skin necrosis. IEAT was frequent in resistant bacteria infections. Mortality occurred mainly in older patients with septic shock, resistant bacteria and IEAT. These results might guide empirical antibiotic therapy in this high-risk population.

Muscular and hepatosplenic candidiasis in a patient with acute myeloblastic leukemia: A case report and literature review

Key Clinical Message

Muscular and subcutaneous candidiasis is a rare entity in immunocompromised patients, but it should be kept in mind when we see multiple cystic soft tissue masses in addition to target-shaped hepatosplenic lesions in neutropenic patients. US and MRI are useful imaging modalities for the diagnosis and follow-up of these patients.

Abstract

Soft tissue candidiasis is an opportunistic infection in immunocompromised patients and must always be diagnosed and treated as soon as possible. In this case report, the patient is a 14-year-old boy with acute myeloid leukemia M3-type who presented with numerous soft tissue and hepatosplenic candidal abscesses.

Factors associated with mortality in patients with extremity necrotizing soft-tissue infections: a single academic center experience

PURPOSE

Necrotizing soft-tissue infection (NSTI) is a surgical emergency associated with high mortality. This study primarily aimed to identify the factors associated with in-hospital mortality due to NSTI in the extremities at a single institution. Secondarily, we aimed to clarify the effectiveness of the optimal combination of hyperbaric oxygen therapy (HBOT) and surgery for NSTI treatment.

STUDY DESIGN

Retrospective observational study.

METHODS

This study included all patients newly diagnosed with NSTI in the extremity from 2003 to 2021 in our hospital. Factors associated with mortality, including patient's characteristics, duration from onset to hospitalization, NSTI type, and clinical data at the initial visit; acute disseminated intravascular coagulation (DIC), laboratory risk indicator for necrotizing fasciitis score, and sequential organ failure assessment score; treatment, initial surgery, surgery times, amputation, HBOT, combined surgery with HBOT, and clinical outcomes; amputation rate, mortality rate, and hospitalization duration were examined.

RESULTS

A total of 37 cases were treated for NSTIs. The median age was 64 years (range: 22-86). Five cases (13.5%) died during hospitalization. Ten patients were diagnosed with DIC at the initial visit, of whom four died. HBOT combined with surgery was performed in 23 cases, and 16 cases underwent multiple surgeries. Factors associated with mortality included DIC (p = 0.015, 95% confidence interval [CI]: 0.015-0.633) and multiple surgeries combined with HBOT (p = 0.028, 95% CI: 1.302-95.418).

CONCLUSION

This study demonstrates that DIC at the initial visit is associated with mortality in extremity NSTI. Additionally, HBOT might improve prognosis when combined with multiple surgeries.

Evaluation of Antibiotic Duration after Surgical Debridement of Necrotizing Soft Tissue Infection

Background: Necrotizing soft tissue infection (NSTI) is known to be a medical emergency with high morbidity and mortality. Guidelines do not specify the optimal duration of antibiotic agents after completion of surgical debridements of NSTI, which has created variable practice. It was hypothesized that patients with NSTI who receive 48 hours or less of post-operative antibiotic agents after final debridement have similar rates of subsequent intervention or infection recurrence, suggesting that a shorter duration of antibiotic agents may treat NSTI adequately after final surgical debridement. Patients and Methods: This was a retrospective study including adults with NSTI identified through International Classification of Diseases, Ninth Revision (ICD-9), International Classification of Diseases, Tenth Revision (ICD-10), and Current Procedural Terminology (CPT) codes admitted to one academic institution between January 1, 2010 and July 31, 2020. Demographics, surgical practices, antibiotic practices, and clinical outcomes including inpatient mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, total antibiotic days, necrotizing infection clinical composite end point (NICCE) success, and infection recurrence were compared based on the duration of antibiotic agents after final debridement. Results: Three hundred twenty-two patients with NSTI were included and baseline characteristics and clinical severity markers were well balanced between the two groups. In 71 patients (22%) who received less than 48 hours of antibiotic agents after final debridement there was no difference in recurrence (1.4% vs. 3.6%; p = 0.697), mortality (1.4% vs. 4.4%; p = 0.476), or ICU LOS (1 vs. 2 days; p = 0.300], but they did have a shorter hospital LOS (7 vs. 10 days; p = 0.011). Conclusions: Shorter duration of antibiotic therapy after final surgical debridement of NSTI may be appropriate in patients without another indication for antibiotic agents.

Antimicrobial Management of Complicated Skin and Soft Tissue Infections in an Era of Emerging Multi-Drug Resistance: Perspectives from 5 Gulf Countries

The number of complicated skin and soft tissue infections (cSSTIs) in the Arabian Gulf region has risen in recent years, particularly those caused by multi-drug resistant (MDR) pathogens. The high prevalence of diabetes, obesity, and associated cardio-metabolic comorbidities in the region renders medical and surgical management of cSSTI patients with MDR infections challenging. An experienced panel of international and regional cSSTI experts (consensus group on cSSTIs) was convened to discuss clinical considerations for MDR infections from societal, antimicrobial stewardship, and cost perspectives, to develop best practice recommendations. This article discusses antibiotic therapies suitable for treating MDR cSSTIs in patients from the Gulf region and recommends that these should be tailored according to the local bacterial ecology by country and region. The article highlights the need for a comprehensive patient treatment pathway and defined roles of each of the multidisciplinary teams involved with managing patients with MDR cSSTIs. Aligned and inclusive definitions of cSSTIs for clinical and research purposes, thorough and updated epidemiological data on cSSTIs and methicillin-resistant <i>Staphylococcus aureus</i> in the region, clearcut indications of novel agents and comprehensive assessment of comparative data should be factored into decision-making are necessary.

Effect of immunoglobulin G on cytokine response in necrotising soft-tissue infection: A post hoc analysis

BACKGROUND

A marked inflammatory response in necrotising soft-tissue infection (NSTI) may contribute to the severe clinical course. Intravenous polyspecific immunoglobulin G (IVIG) is used by some as adjuvant treatment for NSTI, but in the randomised INSTINCT trial, no effect of IVIG in NSTI patients was seen on physical quality of life. In experimental studies, IVIG may induce immunosuppressive effects by reducing the pro-inflammatory response and neutralising circulating superantigens. However, data on the potential immunomodulatory effects are sparse and remain to be investigated in a clinical setting. In this post hoc analysis of the INSTINCT trial, we aimed to assess the effect of IVIG on various inflammatory cytokines up to day 3 after randomisation.

METHODS

Tumour necrosis factor (TNF), interleukin-1β, interleukin-6, interleukin-10 and granulocyte colony-stimulating factor were measured at admission, days 1, 2 and 3.

RESULTS

A total of 100 ICU patients with NSTI were included; 50 were allocated to IVIG (25 g/d for 3 days) and 50 to placebo. No difference in the overall inflammatory response was observed between groups except from TNF, which was higher in the IVIG group as compared to the placebo group (area under curve-admission to day 3, 93.6 vs 60.2, P = .02). Similarly, no differences were observed in percentage change from baseline to day 3 in any of the studied cytokines between patients allocated to IVIG group and those allocated to placebo group.

CONCLUSION

In ICU patients with NSTI, IVIG did not reduce the plasma concentration of cytokines in the first 3 days.

High-Dose versus Standard-Dose Tigecycline Treatment of Secondary Bloodstream Infections Caused by Extensively Drug-Resistant Acinetobacter baumannii: An Observational Cohort Study

Background

Extensively drug-resistant Acinetobacter baumannii (XDR-AB) infections have become difficult to treat and are associated with a high mortality rate. Tigecycline is one of the most effective agents used to treat XDR-AB infections, but data from treating bloodstream infection (BSI) in standard dose do not look promising, because of its low plasma concentration. Secondary BSI with primary infection source may indicate tigecycline treatment with a higher dose. Currently, little is known about the application of high-dose tigecycline among patients with secondary BSI caused by XDR-AB. We aimed to investigate the outcomes for high-dose (HD) tigecycline treatment versus standard-dose (SD) treatment of these patients.

Methods

An observational cohort study was conducted at four university affiliated hospitals in mainland China. Adult inpatients who were confirmed as having secondary BSI caused by XDR-AB and received definitive tigecycline treatment were consecutively included. Patients who were treated with 50 mg every 12 h were defined as the SD group, and a twice dose was defined as the HD group.

Results

Of the enrolled patients, 63 received SD and 88 received HD tigecycline treatment. Patients in the two groups had similar with regard to baseline clinical conditions. The 30-day survival was affected by the source of the primary infection. Survival was significantly better in patients with non-pulmonary-infection-related BSI than in patients with pulmonary-infection-related BSI. Multivariate Cox regression confirmed that HD had a protective effect only observed in patients with non-pneumonia-related BSI.

Conclusion

A tigecycline dose that is twice its standard dose is better for the treatment of XDR-AB infection only in BSI associated with non-pulmonary infection.

Current management of necrotizing soft-tissue infections

PURPOSE OF REVIEW

The aim of the article is to present recent epidemiological, microbiological, and clinical data for the surgical, antimicrobial, and adjunctive management of necrotizing soft-tissue infections (NSTI).

RECENT FINDINGS

NSTI can be caused by a broad variety of organisms. Reports about NSTI caused by multidrug-resistant bacteria are increasing. Owing to the rareness of NSTI, general clinical awareness is low and prompt diagnosis is often delayed. New diagnostic instruments (scoring systems, MRI) have either a low accuracy or are time consuming and cannot guide clinicians reliable currently. The value of adjunctive measures (intravenous immunoglobulin, hyperbaric oxygen therapy) is uncertain as well. Morbidity and mortality in NSTI remain high, ranging from 20 up to over 30%.

SUMMARY

Early radical surgical debridement and empirical broad-spectrum antimicrobial treatment remain the cornerstones of therapy in NSTI. Further clinical research is necessary to shorten diagnostic pathways and to optimize surgical, antimicrobial, and adjunctive treatment.

Dynamic Changes in Microbial Composition During Necrotizing Soft-Tissue Infections in ICU Patients

Introduction: Recent studies described the threat of emerging multidrug-resistant (MDR) bacteria in intensive care unit (ICU) patients, but few data are available for necrotizing skin and soft tissue infections (NSTI). In a cohort of ICU patients admitted for NSTI, we describe the dynamic changes of microbial population during repeated surgeries.

Materials and Methods: This retrospective study compiled consecutive cases admitted for the management of severe NSTI. Clinical characteristics, NSTI features, morbidity and mortality data were collected. The microbiological characteristics of surgical samples obtained during initial surgery were compared with those obtained during the first reoperation, including persistence of initial pathogens and/or emergence of microorganisms. Risk factors for emergence of microorganisms and MDR bacteria were assessed by univariable and multivariable analyses.

Results: Among 100 patients {63% male, 58 years old [interquartile ratio (IQR) 50–68]} admitted for NSTI, 54 underwent reoperation with a median [IQR] delay of 3 (1–7) days. Decreased proportions of susceptible strains and emergence of Gram-negative bacteria, including Pseudomonas aeruginosa, staphylococci and enterococci strains, were reported based on the cultures of surgical specimen collected on reoperation. On reoperation, 22 (27%) of the isolated strains were MDR (p < 0.0001 vs. MDR bacteria cultured from the first samples). Broad-spectrum antibiotic therapy as first-line therapy was significantly associated with a decreased emergence of microorganisms. Adequate antibiotic therapy from the initial surgery did not modify the frequency of emergence of microorganisms (p = 0.79) and MDR bacteria (p = 1.0) or the 1-year survival rate.

Conclusion: The emergence of microorganisms, including MDR bacteria, is frequently noted in NSTI without affecting mortality.

Surgical Infection Society 2020 Updated Guidelines on the Management of Complicated Skin and Soft Tissue Infections

Background: The Surgical Infection Society (SIS) Guidelines for the treatment of complicated skin and soft tissue infections (SSTIs) were published in October 2009 in Surgical Infections. The purpose of this project was to provide a succinct update on the earlier guidelines based on an additional decade of data. Methods: We reviewed the previous guidelines eliminating bite wounds and diabetic foot infections including their associated references. Relevant articles on the topic of complicated SSTIs from 2008-2020 were reviewed and graded individually. Comparisons were then made between the old and the new graded recommendations with review of the older references by two authors when there was disparity between the grades. Results: The majority of new studies addressed antimicrobial options and duration of therapy particularly in complicated abscesses. There were fewer updated studies on diagnosis and specific operative interventions. Many of the topics addressed in the original guidelines had no new literature to evaluate. Conclusions: Most recommendations remain unchanged from the original guidelines with the exception of increased support for adjuvant antimicrobial therapy after drainage of complex abscess and increased data for the use of alternative antimicrobial agents.

The Efficacy and Safety of High-dose Daptomycin in the Treatment of Complicated Skin and Soft Tissue Infections in Asians

OBJECTIVE

To compare the efficacy and safety of standard-dose (SD) daptomycin with those of high-dose (HD) daptomycin in complicated skin and soft tissue infections (cSSTIs) in an Asian population.

MATERIALS AND METHODS

Patients from three medical centers diagnosed with cSSTIs were screened in the clinical information system. Patients included in the analysis were divided into two groups: those who received daptomycin at doses ≥ 6 mg/kg (HD group) and those receiving 4 mg/kg (SD group). The demographics and clinical treatment information were analyzed.

RESULTS

Overall, 155 patients were recruited, including 108 patients in the SD group and 47 patients in the HD group. The rate of healthcare-associated infections was higher in the HD group (61.70% vs. 37.04%), demonstrating a statistically significant difference (P = 0.005). Compared with the SD group, the HD group had statistically significant early clinical stabilization (72.34% vs 52.78%, P = 0.023). The results of the multivariate analysis indicated that HD daptomycin was an independent effector for early clinical stabilization (HR=0.394, P < 0.001). The rate of drug-related adverse events was equally distributed in the HD and SD groups (36.17% vs. 26.85%, P = 0.243).

CONCLUSION

Compared with SD daptomycin, HD daptomycin increased the rate of early clinical stabilization in Asian patients with cSSTIs, whereas the incidence of adverse events did not increase.

Acute wound infections management: the 'Don'ts' from a multidisciplinary expert panel

Introduction: The management of acute wounds may be affected by malpractices leading to poor outcome, prolonged hospital stay and inappropriate use of antibiotic therapy.Areas covered: Acute wound infections are represented by surgical site and post-traumatic infections. The aim of this expert opinion is to identify a list of inadvisable actions and to provide a guide for an optimal management of acute wound infections. A literature search using Pubmed/MEDLINE database was performed. Articles pertaining to areas covered published until December 2019 were selected. We identified the most common malpractices in this setting and, using the Choosing Wisely methodology, we proposed a list of "Don'ts" for an easy use in clinical practice.Expert opinion: Malpractices may occur from the surgical prophylaxis to the discharge of patient. A prolonged surgical prophylaxis, the underestimation of signs and symptoms, the omission of source control, the inappropriate collection of wound swab, the improper use of clinical microbiology and pharmacology, the lack of hygiene measures and the delay of discharge are all factors that may lead to unfavorable outcome. A multidisciplinary approach is needed to optimally manage these patients. The "Don'ts" refer to all professional figures involved in the management of patients with acute wound infections.

When to switch to an oral treatment and/or to discharge a patient with skin and soft tissue infections

PURPOSE OF REVIEW

Skin and soft tissue infections prevalence is increasing and represent a frequent cause of hospital admission. New guidelines have become available in order to better define these infections and their response to antimicrobial treatment. Gram-positive bacteria, in particular Staphylococcus aureus, remain the most frequently isolated pathogens in skin and soft tissue infections. To treat complicated forms and infections caused by drug-resistant bacteria, hospital admission and administration of intravenous antibiotics are often required, impacting on healthcare costs and patients' morbidity.

RECENT FINDINGS

New therapeutic options offer efficacy against drug-resistant Gram-positive bacteria as well as potential to favor early patients' discharge, including the possibility for intravenous to oral switch and infrequent drug administration because of prolonged drug half-life. Although data from real-world studies on new antimicrobials is awaited, clinicians need clear direction on how to optimize the treatment of skin and soft tissue infections in order to avoid prolonged hospitalizations and extra costs. Early assessment of patient's clinical conditions and response to treatment appear useful in order to facilitate patients' discharge.

SUMMARY

We have reported the evidence for early intravenous to oral switch and early hospital discharge for patients with skin and soft tissue infections. New therapeutic options that represent promising tools in promoting an optimized management of these infections have also been reviewed.

Combination of Girdlestone Pseudoarthroplasty and Negative Pressure Wound Therapy with Instillation and Dwell in the Treatment of Invasive Osteomyelitis of the Proximal Femur

Osteomyelitis is a progressively destructive invasive infection of the bone that can result in both localized and systemic illness. This includes an acute suppurative infection, generalized weakness, a failure to thrive, a pathological fracture, and non-healing ulcers. When chronic osteomyelitis develops, therapeutic options are limited, as antimicrobial agents cannot penetrate the necrotic bone, and repeated surgical debridement may be needed. Re-establishing full thickness coverage of the wounds and ulcers associated with osteomyelitis is challenging due to factors such as ongoing pressure injury, malnutrition, and resistant microorganisms. Classically, Girdlestone pseudoarthroplasty has been used to manage a resistant and invasive infection of the acetabular cavity and proximal femur, but it is now rarely employed because of the morbidity of removing the femoral head and leaving a wound to heal by secondary intention. Negative pressure wound therapy with instillation and dwell (NPWTi-d) offers a powerful adjunct to the management of complex infections and wound healing. In this case series of invasive osteomyelitis of the proximal femur in non-ambulatory patients, we demonstrate that the combination of the Girdlestone and negative pressure wound therapy with instillation and dwell allows for delayed closure within a week of the initial procedure, with favorable outcomes and no recurrence of osteomyelitis.

The case log of a single surgeon was analyzed retrospectively over an 18-month period. The case series includes all patients who underwent the Girdlestone procedure for invasive osteomyelitis of the femoral head after failed antibiotic management, were non-ambulatory, and were greater than age 18.

A total of 10 patients with 11 Girdlestone operations were found. Patients were predominantly male. The average age was 40 years. All patients were treated with NPWTi-d and then underwent a delayed primary or partial closure on an average of 4.5 days after the initial debridement. All four patients with no pre-existing pressure ulceration of the greater trochanter underwent primary closure without wound complication. Of the remaining patients with pre-operative ulcers of the greater trochanter, three were closed successfully or completely healed secondarily and four had substantial wound healing and reduction in size in the post-operative time period. All but one patient who had pre-operative ulcers of the ipsilateral ischium also had a noted improvement of ulcer dimensions in the postoperative follow-up period. Two patients developed new pressure ulcers on the contralateral side and two patients had a worsening of their pre-existing contralateral pressure ulcers more than 30 days post-operatively. No patient had a recurrence of their osteomyelitis. During the same time period, one patient refused surgical intervention and died secondary to overwhelming sepsis.

Girdlestone pseudoarthroplasty is a radical therapy for refractory invasive osteomyelitis. While it has been historically associated with prolonged or failed wound healing, combining this surgery with negative pressure wound therapy with instillation and dwell allows for the successful eradication of infection. In addition, this facilitates wound healing and closure, providing a powerful alternative to the challenge of refractory invasive osteomyelitis of the hip, an ultimately life-threatening infection.

Clinical, diagnostic, and therapeutic features of patients admitted to acute care hospitals with trunk compared to lower limb cellulitis

The objective of this study is to report the clinical course and risk factors of trunk cellulitis, to identify diagnostic and therapeutic approaches, and compare them to patients with lower limb cellulitis. Medical records of adult patients with trunk cellulitis were reviewed and compared to an equal number of randomly selected patients with lower limb cellulitis. Demographic, clinical, and laboratory data were collected and analyzed using binary univariate and multivariate logistic regression analyses. Primary outcome was surgical drainage. Secondary outcomes were use of imaging studies, length of stay, readmission within 30 days, and 30-day mortality. During the study period, 74 patients were diagnosed with trunk cellulitis. Compared to patients with lower limb cellulitis, there are more women (57 vs. 39%, p = 0.032) and they are younger (mean age 59.7 vs. 68.4 years, p = 0.005). The only co-morbidity found as a significant risk factor for trunk cellulitis is malignancy (p = 0.017). These variables remain independent risk factors for trunk cellulitis after multivariate regression analysis. There is a trend toward more surgical interventions in the study group [6 (8%) patients vs. 1 (1%) with leg cellulitis, p = 0.116], and a longer hospital stay (5.8 days in the study group vs. 4.3 days in the control group, p = 0.025). Laboratory data are similar in both groups. There are risk factors for trunk cellulitis compared to lower limb cellulitis. However, diagnostic and therapeutic approaches are similar, except for a trend for more surgical interventions.

Current understanding in source control management in septic shock patients: a review

Sepsis and septic shock is one of the leading causes of death worldwide. Antibiotics, fluid resuscitation support of vital organ function and source control are the cornerstones for the treatment of these patients. Source control measures include all those actions taken in the process of care to control the foci of infection and to restore optimal function of the site of infection. Source control represents the multidisciplinary team required in order to optimize critical care for septic shock patients. In the last decade an increase interest on fluids, vasopressors, antibiotics, and organ support techniques in all aspects whether time, dose and type of any of those have been described. However information of source control measures involving minimal invasion and new techniques, time of action and outcome without it, is scarce. In this review the authors resumes new information, recommendations and future directions on this matter when facing the more common types of infections.