Necrotizing soft tissue infections: review and current concepts in treatment, systems of care, and outcomes

Utility of Diagnostic Imaging in the Early Detection and Management of the Fournier Gangrene

Fournier gangrene represents a urologic emergency. It is a rapidly progressing necrotizing fasciitis that comprises the perineal, perianal, and genital regions and has a high mortality rate. Diagnosis is usually made clinically, but radiological diagnostics, such as ultrasound (US), computed tomography (CT), or magnetic resonance imaging (MRI), can determine the extent of the disease in relation to pelvic structures. Early and accurate diagnosis precipitates the initiation of the effective treatment and, thus, affects the outcome of the therapy. The article reports an illustrative case study of a patient with Fournier gangrene, secondary to a perianal fistula and perianal abscess with a massive accumulation of fluid around the anus and testicles, requiring unilateral orchidectomy. Rapid radiological diagnosis via MRI enabled precise assessment of the degree of the disease, early surgical intervention, and a successful outcome.

Impact of Comorbidities on the Cause of Death by Necrotizing Soft Tissue Infections

Background: The aim of this study was to identify the cause of death in patients with necrotizing soft tissue infections (NSTIs) stratified by patient's pre-existing comorbidities (American Society of Anesthesiologists [ASA] classification 3/4 vs. ASA 1/2). Differences in clinical presentation, mortality rate, and factors associated with mortality between those two comorbidity groups were investigated. Patients and Methods: A retrospective multicenter study of patients with NSTIs between 2010 and 2020 was conducted. The primary outcome was the cause of death within the first 30 days. Furthermore, factors associated with mortality were identified. All analysis were stratified by severity of comorbidities (ASA 1/2 or ASA 3/4). Results: Of the 187 patients, 39 patients (21%) died within 30 days. American Society of Anesthesiologists 1/2 patients (overall mortality rate, 11%) died more often as direct result of the infection compared with ASA 3/4 patients (overall mortality rate, 33%) (ASA 1/2 group: 92% vs. ASA 3/4 group: 48%; p = 0.013). American Society of Anesthesiologists 3/4 patients died more often due to withdrawal of life-sustaining therapies based on assumed poor outcome after severe critical illness (ASA 1/2 group: 52% vs. ASA 3/4 group: 8%; p = 0.013). Conclusions: Mortality rates of patients with NSTIs varied from 11% in previously healthy patients to 33% in patients with multiple or severe comorbidities. The predominant cause of mortality was overwhelming infection and associated sepsis in healthy patients whereas in patients with multiple or severe pre-existing medical disease, death most often occurred after treatment limitations based on patient's wishes and prognosis.

Use of a bilayer biodegradable synthetic dermal matrix for the management of defects arising from necrotising fasciitis

The aim of this article is to provide a brief overview of necrotising fasciitis, including causative factors, incidence, diagnosis and clinical outcomes. Various surgical treatment options are outlined, including methods of soft tissue reconstruction after wide excision of infected and necrotic tissues. The role of dermal matrices, including a synthetic biodegradable temporising matrix made of polyurethane, are described in terms of wound bed preparation, surgical application and clinical outcomes.

Retroperitoneal necrotizing soft tissue infections: A case report and literature review

Necrotizing soft tissue infections of the retroperitoneal is a rare disease identity. Here we present a 50‐year‐old male patient who underwent surgical exploration for retroperitoneal necrotizing soft tissue infection. Postoperatively, he was put on broad‐spectrum antibiotics. He passed on after the first exploration and debridement.

Retroperitoneal necrotizing soft tissue infections are rare but deadly entities. Maintain a high index of suspicion in patients with a typical peritoneal signs is mandatory for early detection.

Necrotizing fasciitis of the extremities in high and low Charlson Comorbidity Index: A multi-center retrospective cohort study

BACKGROUND

Necrotizing fasciitis (NF) is a life-threatening and acute progressive soft tissue infection and needs early surgical intervention, that is, debridement or amputation. Surgical strategy or prognosis is influenced by the speed of progression and patients' general condition, which can be calculated by the Charlson Comorbidity Index (CCI). The purpose of this study was to investigate the association between the CCI scores and prognosis of patients with NF of the upper/lower extremities.

METHODS

In the retrospective cohort study, we analyzed patients with NF of the upper/lower extremities who were determined to undergo surgery by orthopedic surgeons at four tertiary hospitals between August 2003 and April 2016. We divided the patients into two groups, Group L (low CCI scores of 0-2) and Group H (high CCI scores of ≥3). The primary event of this study was defined as death or amputation. Mortality cases were included when amputation was informed with documented certification but patients died while waiting for surgery. We compared the patients' background, laboratory data on admission, the laboratory risk indicator for necrotizing fasciitis (LRINEC) score, and primary outcome between the two groups.

RESULTS

Of the 56 patients, 28 patients were classified into Group L and the other 28 patients into Group H. The data in this study showed that patients in Group H had lower white blood cell counts and hemoglobin and higher creatinine than Group L, but there was no difference in LRINEC scores between the two groups. Streptococcus pyogenes was the most common infectious agent in Group L (54%) but not in Group H (11%). Poorer outcome was observed in Group H compared with Group L (4 mortality and 16 amputation vs. no mortality and 9 amputation, P = 0.007).

CONCLUSIONS

Laboratory data and causative microorganisms were different between high CCI and low CCI patients with NF. High CCI scores were associated with limb amputation or death caused by NF of the upper/lower extremities; whereas, low CCI scores were more likely associated with S. pyogenes monoinfection.

Necrotizing Fasciitis of the Upper Extremity – A Review

Necrotizing fasciitis is a soft tissue infection that habitually originates from the fascial sheaths, expands at a volant pace, leads to extensive necrosis of the subcutaneous tissues, and eventually ends up in a life-threatening condition with notably elevated amputation and mortality rates. Factors that induce interruption of skin integrity, such as trauma or intravenous drug use, are the most common inciting events. Specific clinical signs heralding its presence are usually absent in the early stages, often resulting in misdiagnosis. Early recognition, prompt and aggressive surgical debridement, antibiotic use, and supportive care constitute the fundamental principles to lean on for a better prognosis. Necrotizing fasciitis of the upper extremity is relatively rare and consequently holds a limited place in the literature. Only a few studies assess it as a separate entity, with most of them being case reports or small case series. We, therefore, performed a review of the current literature, to assemble the dispersed results of different studies and clarify the various aspects of upper limb necrotizing fasciitis. In this systematic review, we present the epidemiological data, the causative events, the most frequent underlying diseases, the risk factors, the amputation and mortality rates, the pathogenic microorganisms, the clinical characteristics, the diagnostic tools, the medical and surgical management concerning necrotizing fasciitis of the upper limb. Finally, the results indicating its differentiation compared to necrotizing fasciitis of other anatomic sites are remarkably highlighted.

Surgical Management of Necrotizing Fasciitis of the Head and Neck

OBJECTIVE

The purpose of this study was to highlight risk factors and surgeries for necrotizing fasciitis (NF) of the head and neck in the literature. NF is rare but can rapidly progress.

MATERIALS AND METHODS

A literature search was done using PubMed and SCOPUS. Articles that discussed NF of the head and neck and a specific surgical technique were included. A bivariate Pearson correlation was conducted using an α level of 0.05.

RESULTS

The study included 31 articles encompassing 77 patients who presented with head and neck NF. Diabetes mellitus (23.4%) was the most common comorbidity observed. Surgical techniques, such as debridement (96.10%) and incision/exploration (97.40%), were common.

CONCLUSION

Immediate surgical intervention should be performed when treating patients presenting with NF of the head and neck.

Clinical outcome of multidisciplinary treatment of vulvar necrotising fasciitis

OBJECTIVE

Vulvar necrotising fasciitis (VNF) is a severe soft tissue infection associated with substantial morbidity and high mortality. At Stony Brook Medicine, US, patients with known or suspected VNF are treated by a structured multidisciplinary team consisting of members of the Departments of Emergency Medicine and Medicine, the Divisions of Gynecologic Oncology, Burn and Surgical Intensive Care Units, Infectious Disease and Plastic Surgery, and the nursing, nutrition, physical/occupational therapy and social work services.

METHOD

This is a retrospective review of patients presenting to Stony Brook University Hospital with VNF over an 18-month period.

RESULTS

A total of 10 patients were treated for VNF during the study period. All patients were treated by the structured multidisciplinary team, including extensive initial surgical debridement by the gynaecologic oncologists. All patients survived to discharge.

CONCLUSION

The results of this review demonstrated that prompt diagnosis, rapid implementation of appropriate antibiotic coverage, surgical debridement of necrotic tissue, and comprehensive care delivered by a structured multidisciplinary team contributed to positive clinical outcomes and decreased the risk of death from VNF.

Necrotizing Fasciitis: Evaluation of 85 Cases and Usage of LRINEC Score

Objective

The present study aims to define the characteristics of the necrotizing fasciitis (NF) cases followed at our hospital and to compare our results with the literature.

Materials and Methods

In this study, NF cases followed and treated at our hospital from January 2005 to April 2019 were evaluated retrospectively.

Results

A total of 85 cases of NF were included in the study. Of the cases, 33 (39%) were female and the median age was 59.8±13.1 years (range: 26-92 years). Diabetes mellitus (DM) (56%) was the most prevalent comorbid condition. Extremities were the most frequently involved field found in 41 (48%) of the cases followed by Fournier's gangrene found in 34 (40%) of the cases. All of the cases had undergone surgical intervention (debridement and/or amputation) and received broad-spectrum antibiotic therapy. Laboratory risk indicator for necrotizing fasciitis (LRINEC) score was calculated for 60 cases, and it was 6 or higher in 78% of them. Nineteen (22%) of 85 cases had died.

Conclusion

Necrotizing fasciitis affects generally older male patients with DM. In NF cases to avoid the higher risk of mortality, the removal of necrotic tissue via surgical procedure together with antimicrobial therapy is required urgently; therefore, it is very important to differentiate NF from soft tissue infections as soon as possible. As the LRINEC score predicted NF among nearly 80% of our patients, this score could be used as an early diagnostic tool of NF.

Level of Evidence

Level IV, case series.

In-hospital mortality associated with necrotizing soft tissue infection due to Vibrio vulnificus: a matched-pair cohort study

Background

It remains unclear whether Vibrio vulnificus necrotizing soft tissue infection (NSTI) is associated with higher mortality compared with non-Vibrio NSTI. This study’s objective was to compare outcomes including in-hospital mortality and prognosis between patients with V. vulnificus NSTI and those with non-Vibrio NSTI.

Method

A retrospective 1:2 matched-pair cohort study of hospitalized patients with NSTI diagnosed by surgical finding was conducted in two tertiary hospitals in southern Taiwan between January 2015 and January 2020. In-hospital outcomes (mortality, length of stay) were compared between patients with and without V. vulnificus infection. We performed multiple imputation using chained equations followed by multivariable regression analyses fitted with generalized estimating equations to account for clustering within matched pairs. All-cause in-hospital mortality and length of stay during hospitalization were compared for NSTI patients with and without V. vulnificus.

Result

A total of 135 patients were included, 45 in V. vulnificus NSTI group and 90 in non-Vibrio group. The V. vulnificus NSTI patients had higher mortality and longer hospital stays. Multivariable logistic regression analysis revealed that V. vulnificus NSTI was significantly associated with higher in-hospital mortality compared with non-Vibrio NSTI (adjusted odds ratio = 1.52; 95% confidence interval 1.36–1.70; p < 0.01).

Conclusion

Vibrio vulnificus NSTI was associated with higher in-hospital mortality and longer hospital stay which may increase health care costs, suggesting that preventing V. vulnificus infection is essential.

Clostridium perfringens-Induced Necrotic Diseases: An Overview

Clostridium perfringens, a prevalent Gram-positive bacterium, causes necrotic diseases associated with abundant life loss and economic burdens of billions of USD. The mechanism of C. perfringens-induced necrotic diseases remains largely unknown, in part, because of the lack of effective animal models and the presence of a large array of exotoxins and diverse disease manifestations from the skin and deep tissues to the gastrointestinal tract. In the light of the advancement of medical and veterinary research, a large body of knowledge is accumulating on the factors influencing C. perfringens-induced necrotic disease onset, development, and outcomes. Here, we present an overview of the key virulence factors of C. perfringens exotoxins. Subsequently, we focus on comprehensively reviewing C. perfringens-induced necrotic diseases such as myonecrosis, acute watery diarrhea, enteritis necroticans, preterm infant necrotizing enterocolitis, and chicken necrotic enteritis. We then review the current understanding on the mechanisms of myonecrosis and enteritis in relation to the immune system and intestinal microbiome. Based on these discussions, we then review current preventions and treatments of the necrotic diseases and propose potential new intervention options. The purpose of this review is to provide an updated and comprehensive knowledge on the role of the host–microbe interaction to develop new interventions against C. perfringens-induced necrotic diseases.

Diagnostic performance of MRI and CT in diagnosing necrotizing soft tissue infection: a systematic review

OBJECTIVE

To systematically review the accuracy of MRI and CT in diagnosing necrotizing soft tissue infection (NSTI).

METHODS

MEDLINE and Embase were searched for original studies which reported the diagnostic performance of MRI or CT in detecting NSTI. Individual study quality was assessed using the QUADAS-2 tool. Sensitivity and specificity of MRI and CT were calculated and, if supported by data from at least two studies, pooled using a bivariate random-effects model.

RESULTS

Six MRI studies and 7 CT studies were included. There were no major concerns with regard to study quality and applicability. The included studies used multiple diagnostic criteria, with sensitivities and specificities of both MRI and CT ranging between 0 and 100%. T2 hyperintensity of deep fascia was the most commonly used diagnostic MRI criterion (5 studies), yielding a pooled sensitivity of 86.4% (95% confidence interval [CI] 76.1-92.7%) and a pooled specificity of 65.2% (95% CI 35.4-86.6%). Presence of gas was the most commonly used diagnostic CT criterion (3 studies), yielding a pooled sensitivity of 48.6% (95% CI 37.1-60.2%) and a pooled specificity of 93.2% (95% CI 73.3-98.5%).

CONCLUSION

T2 hyperintensity of deep fascia at MRI has high sensitivity and moderate specificity in diagnosing NSTI. Presence of gas at CT has low sensitivity but high specificity. A combination of diagnostic criteria may improve diagnostic performance, but this needs further investigation.

Necrotizing Soft Tissue Infections (NSTI): Pearls and Pitfalls for the Emergency Clinician

BACKGROUND

Skin and soft tissue infections are common emergency department (ED) presentations. These infections cover a wide spectrum of disease, from simple cellulitis to necrotizing fasciitis. Despite the commonality, a subset of skin and soft tissue infections known as necrotizing soft tissue infections (NSTIs) can cause significant morbidity and mortality.

OBJECTIVE

This review evaluates the current evidence regarding the presentation, evaluation, and management of NSTI from the ED perspective.

DISCUSSION

NSTIs are commonly missed diagnoses. History and physical examination findings are inconsistent, and the risk factors for this high mortality disease are common amongst ED populations. Laboratory evaluation and the Laboratory Risk in Necrotizing Fasciitis (LRINEC) score is helpful but is insufficient to rule out the disease. Imaging modalities including ultrasound, computed tomography, and magnetic resonance imaging are highly sensitive and specific, but may delay definitive management. The gold standard for diagnosis includes surgical exploration. Surgical intervention and empiric broad-spectrum antibiotic coverage are the foundations of treatment. Adjuvant therapies including hyperbaric oxygen and intravenous immunoglobulin have not yet been proven to be beneficial or to improve outcome.

CONCLUSION

NSTIs are associated with significant morbidity and mortality. Knowledge of the history, examination, evaluation, and management is vital for emergency clinicians.

Increased Vascular Permeability Due to Spread and Invasion of Vibrio vulnificus in the Wound Infection Exacerbates Potentially Fatal Necrotizing Disease

Vibrio vulnificus is known to cause necrotizing soft tissue infections (NSTIs). However, the pathogenic mechanism causing cellulitis, necrotizing fasciitis, muscle necrosis, and rapidly developing septicemia in humans have not been fully elucidated. Here, we report a multilayer analysis of tissue damage after subcutaneous bacterial inoculation as a murine model of V. vulnificus NSTIs. Our histopathological examination showed the progression of cellulitis, necrotizing fasciitis, and muscle necrosis worsening as the infection penetrated deeper into the muscle tissue layers. The increase in vascular permeability was the primary cause of the swelling and congestion, which are acute signs of inflammation in soft tissue and characteristic of human NSTIs. Most importantly, our sequential analysis revealed for the first time that V. vulnificus not only spreads along the skin and subcutaneous tissues or fascia but also invades deeper muscle tissues beyond the fascia as the crucial process of its lethality. Also, increased vascular permeability enabled V. vulnificus to proliferate in muscle tissue and enter the systemic circulation, escalating the bacterium’s lethality. Our finding may yield important clinical benefits to patients by helping physicians understand the impact of surgical debridement on the patient’s quality of life. Furthermore, this study provides a promising system to accelerate studies of virulence factors and eventually help establish new therapies.

Necrotizing fasciitis a review

Necrotizing fasciitis is an uncommon, rapidly progressive, often aggressive bacterial infection that causes extensive necrosis of the subcutaneous tissue and fascia, relatively sparing the muscle and skin tissues. Rapid diagnosis of the disease is mandatory because the delay in initiation of aggressive treatment negatively influences the outcome. Specific clinical signs may not be always present, which makes an accurate and timely diagnosis difficult. Based on the literature, this article presents a review of the historical background, etiology, pathophysiology, clinical findings, diagnostic strategies, treatment and prognosis of the disease.

The development of surgical risk score and evaluation of necrotizing soft tissue infection in 161 Naja atra envenomed patients

BACKGROUND

Naja atra bites cause wound necrosis, secondary infection, and necrotizing soft tissue infection (NSTI) requiring repetitive surgeries. Little information is known about the predictors for surgery after these bites.

MATERIALS AND METHODS

We retrospectively evaluated 161 patients envenomed by N. atra, 80 of whom underwent surgery because of wound necrosis and infection. We compared the patients' variables between surgical and non-surgical groups. To construct a surgical risk score, we converted the regression coefficients of the significant factors in the multivariate logistic regression into integers. We also examined the deep tissue cultures and pathological findings of the debrided tissue.

RESULTS

A lower limb as the bite site, a ≥3 swelling grade, bullae or blister formation, gastrointestinal (GI) effects, and fever were significantly associated with surgery in the multivariate logistic regression analysis. The surgical risk scores for these variables were 1, 1, 2, 1, and 2, respectively. At a ≥3-point cutoff value, the model has 71.8% sensitivity and 88.5% specificity for predicting surgery, with an area under the receiver operating characteristic curve of 0.88. The histopathological examinations of the debrided tissues supported the diagnosis of snakebite-induced NSTI. Twelve bacterial species were isolated during the initial surgery and eleven during subsequent surgeries.

DISCUSSION AND CONCLUSIONS

From the clinical perspective, swelling, bullae or blister formation, GI effects, and fever appeared quickly after the bite and before surgery. The predictive value of these factors for surgery was acceptable, with a ≥3-point risk score. The common laboratory parameters did not always predict the outcomes of N. atra bites without proper wound examination. Our study supported the diagnosis of NSTI and demonstrated the changes in bacteriology during the surgeries, which can have therapeutic implications for N. atra bites.

Necrotizing Soft Tissue Infections of the Hand and Wrist

Necrotizing soft tissue infections of the upper extremity threaten life and limb. Their presentation is often difficult to recognize and multiple factors contribute to the varied presentation, speed of spread, and morbidity of the disease process. The only treatment to be definitively shown to improve outcomes is prompt surgical treatment. It should be expected to perform multiple debridements as well as reconstructive procedures once the infection and necrosis has been arrested. The use of a multidisciplinary team is mandatory to optimize care for these patients. Despite advances in knowledge and treatment, these infections still have high mortality and morbidity.

Necrotizing Bacterial Myositis as the Initial Presentation of Severe Aplastic Anaemia

Introduction

Necrotizing soft tissue infections are rapidly progressing infections associated with severe inflammation and cytokine release. Early recognition and surgical intervention are key factors to secure survival. The current case presents a patient with multifocal necrotizing soft tissue infection as the initial presentation of severe aplastic anaemia. Case Presentation. A man in his fifties was admitted with septic shock with multiorgan failure and severe pancytopenia, after two days of malaise with high fever and right flank pain. The diagnosis streptococcal necrotizing myositis was significantly delayed due to atypical clinical findings. After initial surgical exploration, the decision was made to defer from surgical debridement due to extensive involvement of several muscle groups, grave pancytopenia, and suspected dismal prognosis. Surprisingly, the patient stabilized after antibiotics and intensive care treatment. Based on severe pancytopenia and hypocellular bone marrow, with no evidence of other bone marrow disorders, the patient was diagnosed with aplastic anaemia. Treatment for aplastic anaemia with antithymocyte globulin, cyclosporine, and eltrombopaq was started, and 2 months later, a partial haematological recovery was observed. The patient could be discharged from hospital without antibiotic treatment.

Conclusions

This case illustrates the crucial role of a multidisciplinary approach on admission and further during the clinical course. Clinical improvement despite severe neutropenia and stabilization during immunosuppressive therapy suggest that immunological factors modulate clinical course in necrotizing soft tissue infections.

Necrotizing fasciitis of the chest wall: A clinical case report and literature review

Necrotizing fasciitis of the chest wall is a very rare pathology, but with significant mortality, representing a therapeutic challenge. All international reports indicate the need for early diagnosis and an aggressive medical-surgical attitude in order to improve the prognosis. In addition to a review of literature, we present a case developed secondary to a thoracic pleural drainage for pyopneumothorax associated with significant bronchopleural fistula in a destroyed tuberculous left lung. Along with medical treatment, extensive surgical debridement was required. Despite drainage incisions and negative pressure wound therapy (NPWT), the evolution of the fasciitis was difficult, due to bronchopleurocutaneous fistula. Thus, the Azorin procedure (transcervical mediastinoscopic closure of the left main bronchus) was performed. Once this procedure was completed, the inflammatory phenomena were controlled which allowed for a second step consisting of left pneumonectomy, with the application of specific methods for the prevention of bronchial fistula. The clinical case was a therapeutic challenge requiring a complex, staged, multidisciplinary approach due to both the immunocompromised terrain and the severity of the lesions. In conclusion, early recognition and aggressive and combined application of medical and surgical treatment methods can ensure therapeutic success.

Impact of Early Surgical Intervention of Plastic Surgeons on the Prognosis of Necrotizing Soft Tissue Infection

Background

Necrotizing soft tissue infection (NSTI) is a rare, severe bacterial infection that causes rapidly progressive soft tissue necrosis from the skin to the muscle. The gold standard for treating NSTI is a prompt diagnosis, early surgical debridement of necrotic tissue, and antimicrobial therapy. This study investigated the relationship between the involvement of plastic surgeons and the clinical course of NSTI cases treated at Yokosuka General Hospital Uwamachi.

Methodology

This study involved 28 patients with NSTI who were treated at Yokosuka General Hospital Uwamachi. Patient background, outcomes (mortality and amputation), and days to the first surgery were compared in the early and nonearly plastic surgery intervention groups. Moreover, the duration of treatment was also compared in surviving patients. Differences between the two groups were analyzed using Fisher’s direct probability test, Mann-Whitney U test was used for comparison of continuous variables between the two groups, and Spearman’s rank correlation analysis was used for the bivariate correlation coefficient. The significance level was set at <5%.

Results

There were eight and 20 patients in the early and nonearly plastic surgery intervention groups (14 in later intervention and six in nonintervention), respectively. A difference in the median number of days to the first surgery between the early (zero days) and the nonearly (two days) intervention groups was significant (p = 0.002). In the survival groups, the median treatment duration in the early (n = 8) and nonearly (n = 13) intervention groups was 44 and 82 days, respectively, which was significantly shorter in the early intervention group (p = 0.003).

Conclusions

The number of days until the first surgery and the length of the treatment period were significantly shorter in the early plastic surgery intervention group than in the nonearly intervention group.

Novel Clinical Risk Scoring Model for Predicting Amputation in Patients With Necrotizing Fasciitis: The ANF Risk Scoring System

Background: Necrotizing fasciitis (NF) is a life-threatening infection of the skin and soft tissue that spreads quickly and requires immediate surgery and medical treatment. Amputation or radical debridement of necrotic tissue is generally always required. The risks and benefits of both the surgical options are weighed before deciding whether to amputate or debride. This study set forth to create an easy-to-use risk scoring system for predicting the risk scoring system for amputation in patients with NF (ANF).

Methods: This retrospective study included 1,506 patients diagnosed with surgically confirmed NF at three general hospitals in Thailand from January 2009 to December 2012. All diagnoses were made by surgeons who strictly observed the guidelines for skin and soft tissue infections produced by the Infectious Diseases Society of America. Patients were randomly allocated to either the derivation (n = 1,193) or validation (n = 313) cohort. Clinical risk factors assessed at the time of recruitment were used to create the risk score, which was then developed using logistic regression. The regression coefficients were converted into item scores, and the total score was calculated.

Results: The following four clinical predictors were used to create the model: female gender, diabetes mellitus, wound appearance stage 3 (skin necrosis and gangrene), and creatinine ≥1.6 mg/dL. Using the area under the receiver operating characteristic curve (AuROC), the ANF system showed moderate power (78.68%) to predict amputation in patients with NF with excellent calibration (Hosmer-Lemeshow χ² = 2.59; p = 0.8586). The positive likelihood ratio of amputation in low-risk (score ≤ 4) and high-risk (score ≥ 7) patients was 2.17 (95%CI: 1.66–2.82) and 6.18 (95%CI: 4.08–9.36), respectively. The ANF system showed good performance (AuROC 76.82%) when applied in the validation cohort.

Conclusion: The developed ANF risk scoring system, which includes four easy to obtain predictors, provides physicians with prediction indices for amputation in patients with NF. This model will assist clinicians with surgical decision-making in this time-sensitive clinical setting.

The characteristics of oro-cervical necrotizing fasciitis-Comparison with severe cellulitis of oro-cervical region and necrotizing fasciitis of other body regions

Background

Necrotizing fasciitis (NF) is an acute and life-threatening soft-tissue infection however rarely seen in oro-cervical region. Therefore, the details of oro-cervical NF (OCNF) are not well known. The purpose of this study was to investigate the characteristics of OCNF by comparing it with severe cellulitis of oro-cervical region (OCSC) or NF of other body regions (e.g., limb, perineum, and trunk) (BNF), respectively.

Materials and methods

At first, various risk factors for OCNF in oro-cervical severe infection (OCSI; composed of OCNF and OCSC), including neutrophil-to-lymphocyte ratio (NLR) and Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score, were investigated by univariate and multivariate analyses. Next, the differences between OCNF and BNF, including inflammatory markers and mortality, were investigated.

Results

In the present study, 14 out of 231 OCSI patients had OCNF. Multivariate analyses of OCSI patients showed that NLR ≥15.3 and LRINEC score ≥6 points were significantly related to OCNF. During the same period, 17 patients had BNF. The OCNF group had significantly higher inflammatory markers than the BNF group when diagnosis, but significantly lower clinical stages at the time and mortality as outcomes.

Conclusion

We found that compared to BNF, OCNF can be detected at lower clinical stage by using indexes, such as NLR and LRINEC score, besides clinical findings, which may help contributing to patient’s relief.

Point of Care Ultrasound in the Diagnosis of Necrotizing Fasciitis

BACKGROUND

Necrotizing fasciitis (NF) is a severe, life-threatening soft tissue infection requiring prompt diagnosis and immediate surgical debridement. Imaging, including a computed tomography (CT) scan, can often aid in the diagnosis, though it can prolong time to treatment and diagnosis. Point-of-care ultrasound (POCUS) is often used in the ED to identify soft tissue infections. The objective of this study is to evaluate the use of POCUS to identify NF in patients presenting to the emergency department.

METHODS

We prospectively enrolled patients who presented to the emergency department (ED) with suspected soft tissue infection who received a computed tomography and/or surgical consult. POCUS images of the suspected site of infection were obtained by the emergency medicine physician and interpreted based on sonographic findings of NF. These findings were compared with CT scan or surgical impression.

RESULTS

We enrolled 64 patients in this study. Eight were determined to be at high risk of having NF based on CT scan and/or surgical impression. All of these patients also had POCUS images interpreted as concerning for NF. Furthermore, 56 patients were classified as being low risk for having NF based on CT scan and/or surgical impression. All but one of these patients had POCUS images interpreted as not concerning for NF.

CONCLUSIONS

Our data indicates that POCUS can be used to identify NF with a high sensitivity and specificity.

Necrosis-induced apoptosis promotes regeneration in Drosophila wing imaginal discs

Regeneration is a complex process that requires a coordinated genetic response to tissue loss. Signals from dying cells are crucial to this process and are best understood in the context of regeneration following programmed cell death, like apoptosis. Conversely, regeneration following unregulated forms of death, such as necrosis, have yet to be fully explored. Here, we have developed a method to investigate regeneration following necrosis using the Drosophila wing imaginal disc. We show that necrosis stimulates regeneration at an equivalent level to that of apoptosis-mediated cell death and activates a similar response at the wound edge involving localized JNK signaling. Unexpectedly, however, necrosis also results in significant apoptosis far from the site of ablation, which we have termed necrosis-induced apoptosis (NiA). This apoptosis occurs independent of changes at the wound edge and importantly does not rely on JNK signaling. Furthermore, we find that blocking NiA limits proliferation and subsequently inhibits regeneration, suggesting that tissues damaged by necrosis can activate programmed cell death at a distance from the injury to promote regeneration.

Short Courses of Antibiotics Are Safe in Necrotizing Soft Tissue Infections

INTRODUCTION

Necrotizing soft tissue infections (NSTIs) carry high morbidity and mortality. While early aggressive surgical debridement is well-accepted treatment for NSTIs, the optimum duration of adjunct antibiotic therapy is unclear. An increasing focus on safety and evidence-based antimicrobial stewardship suggests a value in addressing this knowledge gap.

OBJECTIVE

To determine whether shorter antibiotic courses have similar outcomes compared to longer courses in patients with NSTI following adequate source control.

POPULATION

142 consecutive patients with surgically managed NSTI were identified on retrospective chart review between December 2014 and December 2018 at two academic medical centers.

RESULTS

Patients were predominately male (74%) with a median age of 52 and similar baseline characteristics. The median number of debridements to definitive source control was 2 (IQR 1-3) with the short course group undergoing a greater number of debridements control 2.57 ± 1.8 vs 1.9 ± 1.2, (P = .01). Of 142 patients, 34.5% received a short course and the remaining 65.5% received a longer course of antibiotics. There was no significant difference in the incidence of bacteremia or wound culture positivity between groups. There was also no significant difference in in-hospital mortality, 8% vs 6% (P = .74), incidence of C. difficile infection, median length of stay, or 30-day readmission.

CONCLUSION

Provided adequate surgical debridement, similar outcomes in morbidity and mortality suggest antibiotic courses of 7 days or less are equally safe compared to longer courses.

Necrotizing Soft Tissue Infection of Left Shoulder and Upper Limb Following Intravenous Injection of Non-steroidal Anti-inflammatory Drug

Necrotizing soft tissue infection (NSTI) is a rapidly spreading and fulminant infection that may occur within any layer of skin and soft tissue and may result in sepsis and multiorgan failure. Cases of intravenous injection of drugs causing NSTIs have been reported, especially involving injection of illicit drugs or insulin. NSTI can be due to polymicrobial or monomicrobial infection and infection involving Klebsiella species has been rising, especially in patients with diabetes mellitus. This is a case of an extensive upper limb and shoulder Klebsiella pneumoniae NSTI following an injection of a non-steroidal anti-inflammatory drug in a diabetic patient. NSTI diagnosis is based on history and clinical examination, supplemented with imaging and laboratory investigations. Early recognition, extensive and serial debridement, antibiotics, and wound management are crucial for the better outcome of the disease. This patient underwent emergent debridement with antibiotics coverage, followed by serial debridement and wound care. The wound healed within the stipulated time, with good function of the affected limb following the rehabilitation program. 

Necrotizing Soft Tissue Infections, the Challenge Remains

Background: Necrotizing Soft Tissue Infections (NSTIs) are uncommon rapidly spreading infection of the soft tissues for which prompt surgical treatment is vital for survival. Currently, even with sufficient awareness and facilities available, ambiguous symptoms frequently result in treatment delay.

Objectives: To illustrate the heterogeneity in presentation of NSTIs and the pitfalls entailing from this heterogeneity.

Discussion: NSTI symptoms appear on a spectrum with on one side the typical critically ill patient with fast onset and progression of symptoms combined with severe systemic toxicity resulting in severe physical derangement and sepsis. In these cases, the suspicion of a NSTI rises quickly. On the other far side of the spectrum is the less evident type of presentation of the patient with gradual but slow progression of non-specific symptoms over the past couple of days without clear signs of sepsis initially. This side of the spectrum is under represented in current literature and some physicians involved in the care for NSTI patients are still unaware of this heterogeneity in presentation.

Conclusion: The presentation of a critically ill patient with evident pain out of proportion, erythema, necrotic skin and bullae is the classical presentation of NSTIs. On the other hand, non-specific symptoms without systemic toxicity at presentation frequently result in a battery of diagnostics tests and imaging before the treatment strategy is determined. This may result in a delay in presentation, delay in diagnosis and delay in definitive treatment. This failure to perform an adequate exploration expeditiously can result in a preventable mortality.

[New Therapeutic Strategies and Future Issues in Hyperbaric Medicine]

Hyperbaric medicine includes two different medical fields: hyperbaric oxygenation (HBO) as emergency and intensive care, and diving medicine. Recent topics in hyperbaric therapy include radiation oncology and regenerative medicine. Of special interest are clinical studies of radiotherapy after HBO that were conducted at some institutes to evaluate its therapeutic effects for cancer patients. A few studies have shown that HBO improves memory disturbance following traumatic brain injury and hypoxic and ischemic events. There is a great possibility that HBO enhances the therapeutic effects of radiotherapy and potentiates regenerative medicine. Randomized controlled trials, however, have indicated the re-examination of its viable treatment effects in some conditions, including decompression illness, carbon monoxide poisoning, and serious soft tissue infection. As recent trends in the treatment of decompression illness have changed on the basis of clinical series, the laws related to diving and caisson work should be amended in the future.

Lactate based Scoring System in the diagnosis of necrotizing fasciitis

INTRODUCTION

Necrotizing fasciitis (NF) is a rare and quickly progressing infection and leads to 100% mortality if untreated. Quick diagnosis and an early and radical surgical treatment are essential for stopping bacterial progression. Unfortunately, the absence of clear clinical signs makes the diagnosis often challenging. Therefore, we searched for easy determinable predictive laboratory markers for NF. This is the first study which includes lactate values in a new score.

MATERIAL AND METHODS

A retrospective analysis of patients with NF (n = 44) and patients with erysipelas (n = 150) was performed. Lactate values, patients` demographics, clinical presentations, site of infection, comorbidities, microbiological and laboratory findings, antibiotic therapies and LRINEC and modified LRINEC Scores were analyzed. Logistic regression analysis was used to derive adjusted weights, and final simple point score was assessed with a ROC curve analysis.

RESULTS

Patients with NF had a mean age of 57 years, patients with erysipelas 65 years. The median hospital length of stay was 8 and 49 days in patients with erysipelas and NF, respectively. While only one patient (0.7 %) in the group of erysipelas died, the mortality rate of patients with NF was 9/44 (20.5 %). The lactate values were statistically significant higher in the NF group 4.1 vs. 2.0 mmol/l (p < 0.001). The new created CologNe-FaDe-Score shows the highest AUC-value with 0.907.

CONCLUSION

With the help of lactate values the CologNe-FaDe-Score consists of easily practicable and highly available parameters, which could sensitize diagnosis.

A large epidemic of a necrotic skin infection in the Democratic Republic of São Tomé and Principe: an epidemiological study

INTRODUCTION

In 2016-18, the Democratic Republic of São Tomé and Príncipe suffered a necrotic skin infection epidemic.

METHODS

A surveillance system was established after increased hospitalisations for this infection. Microbiology results were available for samples analysed in December 2016 and March 2017 using whole genome sequencing and metagenomics. Negative binomial regression was used to study the association of weather conditions with monthly case counts in a time-series analysis.

RESULTS

From October 2016 to October 2018, the epidemic cumulative attack rate was 1.5%. The first peak lasted 5 months, accounting for one-third of total cases. We could not conclusively identify the aetiological agent(s) due to the country's lack of microbiology capacity. Increased relative humidity was associated with increased monthly cases (incidence rate ratio (IRR) 1.05, 95% CI 1.02-1.09), and higher precipitation in the previous month with a higher number of cases in the following month (months with 0-49 mm rainfall compared with months with 50-149 mm and ≥150 mm: IRR 1.44, 95 % CI 1.13-1.78 and 1.50, 95% CI 1.12-1.99, respectively).

DISCUSSION

This epidemic was favoured by increased relative humidity and precipitation, potentially contributing to community-based transmission of ubiquitous bacterial strains superinfecting skin wounds.

FUNDING

World Health Organization Regional Office for Africa, Ministry of Health.

Pre and retroperitoneal necrotizing fasciitis after COVID-19 infection: A case report

Necrotizing fasciitis is a serious infection that originates in the subcutaneous tissues. We present a case of 52 years old male patient who developed preperitoneal and retroperitoneal necrotizing fasciitis 2 weeks after the start of Coronavirus-19 infection. Preoperative abdominal computed tomography with intravenous and oral contrast revealed pre and retroperitoneal spread of air loculi with turbid fluid patches within necrotic tissues. After surgical excision of the lesion, histopathological and microbiological examinations of the samples revealed necrotizing fasciitis. This is the first report of preperitoneal and retroperitoneal necrotizing fasciitis after Coronavirus-19 infection in 52 years old male with no history of trauma or immunocompromised condition. Coronavirus-19 infection may increase the liability of patients to develop overwhelming infection and it may also delay the patient presentation causing serious health-related emergencies. The findings of necrotizing fasciitis on clinical grounds or imaging studies can help in diagnosis as well as the surgical intervention and appropriate antibiotics can highly impact the prognosis and survival of the patient.

Emergency hip disarticulations for severe necrotising fasciitis of the lower limb: a series of rare cases from a rural district general hospital

Hip disarticulation is the removal of the entire lower limb through the hip joint by detaching the femur from the acetabulum. This major ablative procedure is rarely performed for infection but may be required in severe necrotising fasciitis. We present a single centre retrospective review of all cases of emergency hip disarticulations in patients with necrotising fasciitis between 2010 and 2020. All five patients included in the review presented with acute lower limb pain and sepsis. Three patients had comorbidities predisposing them to necrotising fasciitis. Three were deemed to be high risk and two were at intermediate risk of developing necrotising fasciitis. There were two deaths in the postoperative period. Of the three survivors, two required revision surgery for a completion hindquarter amputation and one for flap closure. All three survivors had good functional outcomes after discharge from hospital. Despite its associated morbidity, emergency amputation of the entire lower limb is a life-saving treatment in cases of rapidly progressing necrotising fasciitis and should be considered as a first-line option in managing this condition.

Clinical and Financial Outcomes of Necrotizing Soft-Tissue Infections in Safety-Net Hospitals

Background Prior work has demonstrated inferior outcomes for a multitude of medical and surgical conditions at hospitals with high burdens of underinsured patients (safety-net). The present study aimed to evaluate trends in incidence, clinical outcomes and resource utilization in the surgical management of necrotizing soft-tissue infections (NSTI) at safety-net hospitals. Materials and methods Adults requiring surgical debridement/amputation following NSTI-related hospitalizations were identified in the 2005-2018 National Inpatient Sample. Safety-net status (SNH) was assigned to institutions in the top tertile for annual proportion of underinsured patients. Logistic multivariable regression was utilized to evaluate the association of SNH with mortality, hospitalization duration (LOS), costs and discharge disposition. Results Of an estimated 212,692 patients, 76,719 (36.1%) were managed at SNH. The annual incidence of NSTI admissions increased overall while associated mortality declined. After adjustment, SNH status was associated with greater odds of mortality (adjusted odds ratios: 1.14, 95% CI: 1.03-1.26), LOS (β: +1.8 d, 95% CI: 1.3-2.2) and costs (β: +$4,400, 95% CI: 2,900-5,800). SNH patients had similar rates of amputation but lower likelihood of care facility or home health discharge. Conclusion With a rising incidence and overall reduction in mortality, safety-net hospitals persistently exhibit greater mortality and resource use for surgical NSTI admissions. Variation in access, disease presentation and timeliness of operative intervention may explain the observed findings.

Empagliflozin Use and Fournier’s Gangrene: Case Report and Systematic Literature Review

Background: Fournier’s gangrene (FG) is a rare necrotising soft tissue infection localised in the genital areas with possible dramatic outcomes. Recently, sodium glucose co-transporter-2 (SGLT2) inhibitors were identified as a risk factor. Methods: We present a case report of a 57-year-old female patient with type 2 diabetes mellitus (T2DM) in treatment with empagliflozin which led to the development of FG. Moreover, we performed a systematic review assessing the association between empagliflozin use and FG. Results: The female patient with 15-years treated diabetes presented a massive FG after 6 months from starting empagliflozin. Over the period of two months, she was successfully treated in a low-income setting. The systematic review included two studies with a total of 9915 participants. Although no participant had FG, there was an increased rate of urinary and genital infection in patients treated with empagliflozin compared to those treated with other antidiabetics or placebo. Conclusions: FG should be considered as a possible complication in patients using SGLT2. Patients should be educated to report early signs of genital infection and healthy behaviours as well as a balanced diet should be promoted to aid in the prevention of FG.

Utility of modified Laboratory Risk Indicator for Necrotizing Fasciitis (MLRINEC) score in distinguishing necrotizing from non-necrotizing soft tissue infections

Background

We conducted this study to promote a modified Laboratory Risk Indicator for Necrotizing Fasciitis (MLRINEC) score and evaluate the utility in distinguishing necrotizing fasciitis (NF) from other soft-tissue infections.

Method

A retrospective cohort study of hospitalized patients with NF diagnosed by surgical finding was conducted in two tertiary hospital in southern Taiwan between January 2015 and January 2020. Another group was matched by controls with non-necrotizing soft tissue infections based on time, demographics, and immune status. Data such as infectious location, comorbidities, and laboratory findings were recorded and compared. Logistics regression were used to determine the association with NF after adjustment for confounders and MLRINEC score was developed by then. Receiver operating curve (ROC) and the area under the curve (AUC) were used to evaluate its discriminating ability.

Result

A total of 303 patients were included; 101 in NF group and 202 in non-NF group. We added serum lactate and comorbid liver disease to the original LRINEC score and re-defined the cut-off values for 3 variables to develop the MLRINEC score. The cut-off value for MLRINEC score was 12 points with corresponding sensitivity of 91.8% and a specificity of 88.4%, and the area under ROC (AUC) was 0.893 (95% CI, 0.723 to 0.948; p < 0.01).

Conclusion

MLRINEC score shows a high sensitivity and specificity in distinguishing NF from non-necrotizing soft-tissue infections. Patients with a MLRINEC score > 12 points should be highly suspected of presence of necrotizing fasciitis.

Necrotizing Fasciitis: a Clinical Case and a Review of the Literature

Necrotizing fasciitis is a soft tissue, life-threatening infection with a fulminant and often fatal course. Early diagnosis is usually delayed as the onset of the disease is often masked in the form of erysipelas or cellulite. The condition is characterized by necrosis of the skin, subcutaneous tissue and underlying fascia. We describe a case of a 42-year-old man with a complaint of erythema, fever and severe pain in his right leg 4 days before hospitalization. The patient was admitted and treated with a diagnosis of erysipelas. A few hours after admission, in connection with a drastic deterioration in the general condition and dermatological status, he was transferred to a purulentseptic ward with a fulminant picture of necrotizing fasciitis. Debridement and fasciotomy were performed successfully and timely. Good prognosis and survival in patients with NF correlate directly with the complex of measures. Appropriate antibiotics and intensive general support avoid massive systemic diffusion. Early and adequate surgical debridement and fasciotomy are associated with improved survival.

Chemotactic invasion in deep soft tissue by Vibrio vulnificus is essential for the progression of necrotic lesions

Necrotizing soft tissue infections (NSTI) progress to severe necrosis and result in fatal sepsis within a short time. Vibrio vulnificus is a causative agent and can spread from the initial infection site through soft tissue finally to the systemic circulation of the host. The motility and chemotaxis of this bacterium are essential for proliferation and lethality in a murine model of the infection, but their role in pathogenicity has not been characterized. In this study, we revealed the roles of motility and chemotaxis during the process of V. vulnificus infection. We compared a nonmotile mutant and two nonchemotactic mutants with their parent strain (WT) with regard to bacterial spread using an in vivo imaging system (IVIS) and invasion by detection of bacteria from the muscle and spleen of a murine infection model. WT rapidly spread throughout the infected thigh and invaded deep muscle causing severe tissue damage. The detection rate in the systemic circulation and the lethality were high. On the other hand, the nonmotile mutant stayed at the inoculation site, and the nonchemotactic mutants spread only slowly through the soft tissue of the infected thigh. Detection in the systemic circulation, the degree of tissue damage, and the lethality of nonchemotactic mutants were significantly reduced in mice compared with WT. This study demonstrated that chemotaxis is essential for invasion from the infection site to the deep and distant tissues and the main pathogenic factor for the rapid progression leading to sepsis in V. vulnificus NSTI.

Adjunctive hyperbaric oxygen treatment for necrotising soft-tissue infections: A systematic review and meta-analysis

INTRODUCTION

Surgical intervention, broad-spectrum antibiotics and intensive care support are the standard of care in the treatment of necrotising soft-tissue infections (NSTI). Hyperbaric oxygen treatment (HBOT) may be a useful adjunctive treatment and has been used for almost 60 years, but its efficacy remains unknown and has not been systematically appraised. The aim was to systematically review and synthesise the highest level of clinical evidence available to support or refute the use of HBOT in the treatment of NSTI.

METHODS

The review was prospectively registered (PROSPERO; CRD42020148706). MEDLINE, EMBASE, CENTRAL and CINAHL were searched for eligible studies that reported outcomes in both HBOT treated and non-HBOT treated individuals with NSTI. In-hospital mortality was the primary outcome. Odds ratio (ORs) were pooled using random-effects models.

RESULTS

The search identified 486 papers of which 31 were included in the qualitative synthesis and 21 in the meta-analyses. Meta-analysis on 48,744 patients with NSTI (1,237 (2.5%) HBOT versus 47,507 (97.5%) non-HBOT) showed in-hospital mortality was 4,770 of 48,744 patients overall (9.8%) and the pooled OR was 0.44 (95% CI 0.33-0.58) in favour of HBOT. For major amputation the pooled OR was 0.60 (95% CI 0.28-1.28) in favour of HBOT. The dose of oxygen in these studies was incompletely reported.

CONCLUSIONS

Meta-analysis of the non-random comparative data indicates patients with NSTI treated with HBOT have reduced odds of dying during the sentinel event and may be less likely to require a major amputation. The most effective dose of oxygen remains unclear.

Early and aggressive surgical debridement and negative pressure wound therapy to treat necrotizing fasciitis in three dogs

OBJECTIVE

To report the management and outcomes of dogs with necrotizing fasciitis (NF) treated with early, aggressive surgical debridement and negative pressure wound therapy (NPWT).

STUDY DESIGN

Short case series.

ANIMALS

Three dogs surgically treated for NF.

METHODS

Clinical signs in the three dogs included an identified wound, severe pain, fever, and progressive erythema. A tentative diagnosis of NF was based on the presence of suppurative inflammation and intracellular bacteria seen in fine needle aspirates and clinical progression in each case. Each dog was treated with surgical debridement within 6 hours of clinical suspicion for NF. Necrosis affected multiple tissue layers was noted surgical exploration. Systemic supportive care and antibiotherapy were also provided for 3 to 4 weeks postoperatively.

RESULTS

Three surgical debridements were required in two dogs, and four surgical debridements were required in one dog. All of the surgical sites were managed with NPWT until final primary closure was possible at 4, 5, and 6 days after initial surgery. Results of histopathology and culture of the surgical sites were consistent with NF as described in each case. All dogs survived to discharge and long-term follow up.

CONCLUSION

Management with early surgery, multiple debridements, and the use of NPWT led to resolution of NF in three dogs.

Hyperbaric oxygen treatment is associated with a decrease in cytokine levels in patients with necrotizing soft-tissue infection

BACKGROUND

The pathophysiological understanding of the inflammatory response in necrotizing soft-tissue infection (NSTI) and its impact on clinical progression and outcomes are not resolved. Hyperbaric oxygen (HBO₂ ) treatment serves as an adjunctive treatment; however, its immunomodulatory effects in the treatment of NSTI remains unknown. Accordingly, we evaluated fluctuations in inflammatory markers during courses of HBO₂ treatment and assessed the overall inflammatory response during the first 3 days after admission.

METHODS

In 242 patients with NSTI, we measured plasma TNF-α, IL-1β, IL-6, IL-10, and granulocyte colony-stimulating factor (G-CSF) upon admission and daily for three days, and before/after HBO² in the 209 patients recieving HBO² . We assessed the severity of disease by Simplified Acute Physiology Score (SAPS) II, SOFA score, and blood lactate.

RESULTS

In paired analyses, HBO₂ treatment was associated with a decrease in IL-6 in patients with Group A-Streptococcus NSTI (first HBO₂ treatment, median difference -29.5 pg/ml; second HBO₂ treatment, median difference -7.6 pg/ml), and overall a decrease in G-CSF (first HBO₂ treatment, median difference -22.5 pg/ml; 2^- HBO₂ treatment, median difference -20.4 pg/ml). Patients presenting with shock had significantly higher baseline cytokines values compared to non-shock patients (TNF-α: 51.9 vs. 23.6, IL-1β: 1.39 vs 0.61, IL-6: 542.9 vs. 57.5, IL-10: 21.7 vs. 3.3 and G-CSF: 246.3 vs. 11.8 pg/ml; all p < 0.001). Longitudinal analyses demonstrated higher concentrations in septic shock patients and those receiving renal-replacement therapy. All cytokines were significantly correlated to SAPS II, SOFA score, and blood lactate. In adjusted analysis, high baseline G-CSF was associated with 30-day mortality (OR 2.83, 95% CI: 1.01-8.00, p = 0.047).

CONCLUSION

In patients with NSTI, HBO₂ treatment may induce immunomodulatory effects by decreasing plasma G-CSF and IL-6. High levels of inflammatory markers were associated with disease severity, whereas high baseline G-CSF was associated with increased 30-day mortality.

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.

Utility of the Laboratory Risk Indicator for Necrotizing Fasciitis Score: Comorbid Conditions Do Matter

Background: The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) has been proposed as a diagnostic tool for necrotizing soft tissue infection (NSTI). However, its utility remains underreported, particularly in patients with comorbid conditions. The purpose of this study was to identify the test characteristics of LRINEC for patients with various comorbid conditions. Patients and Methods: We conducted a retrospective study including patients with suspected NSTI. Our study patients were then relegated into the subgroups; intravenous drug use (IVDU), end-stage liver disease (ESLD), and diabetes mellitus (DM). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of a positive LRINEC score (≥ 6 or 8) were calculated in reference to intra-operative findings or results of the pathologic examination. Area under the curve (AUC) using receiver operating characteristic (ROC) plots were compared between each subgroup and the overall study population using DeLong test. Results: A total of 220 patients were included for the analysis. Overall, the sensitivity was 76%, specificity of 52%, PPV of 32%, and NPV of 88%. The subgroup analysis showed low PPVs in all subgroups. The DM and ESLD groups had a high NPV (90.5% and 88.0%, respectively), whereas NPV in the IVDU group was 70.6%. The AUC and DeLong test for the subgroups were 0.649 (p = 0.902) for ESLD, 0.699 (p = 0.683) for DM, and 0.565 (p = 0.034) for IVDU. Conclusions: The LRINEC can be a useful adjunct to rule out the diagnosis of NSTI with exception of IVDU. In contrast, further diagnostic workup might be still required in those patients with positive LRINEC.

Necrotizing fasciitis, causative agents and management: a five-year retrospective study in two tertiary care hospitals in Central Malaysia

PURPOSE

Necrotizing fasciitis (NF) is a rapidly progressive inflammatory infection of the fascia, with secondary necrosis of the subcutaneous tissues. The severity of the disease depends on the virulence of the organism and host immunity. There is a paucity of reports on the prevalence of NF causing pathogens and management.

METHODS

Retrospective data of patients treated for NF were collected from two tertiary care hospitals in Central Malaysia between January 2014 and December 2018.

RESULTS

A total of 469 NF patients were identified. More than half of the NF patients were males (n = 278; 59.28%). The highest number of cases was found among age groups between 30 and 79, with mean age of 56.17. The majority of the NF cases (n = 402; 85.72%) were monomicrobial. Streptococcus spp. (n = 89; 18.98%), Pseudomonas aeruginosa (n = 63; 13.44%) and Staphylococcus spp. (n = 61; 13.01%) were identified as the top three microorganisms isolated. Among the 469 NF cases, 173 (36.8%) were amputated or dead while 296 (63.1%) recovered. Proteus spp. (n = 19; 12.93%), Klebsiella pneumoniae (n = 18; 12.24%) and Escherichia coli (n = 14; 9.52%) were associated with all types of amputations. The most common antibiotic prescribed was unasyn (n = 284; 60.56%), followed by clindamycin (n = 56; 11.94%) and ceftazidime (n = 41; 8.74%). A total of 239 (61.8%) recovered while 148 (38.2%) were either amputated or dead when managed with the unasyn, clindamycin or ceftazidime.

CONCLUSION

This study represents the largest NF cases series in Malaysia highlighting the causative agents and management.

Temporal and seasonal trends of hospitalization and mortality associated with necrotizing fasciitis: A retrospective study of 12 years (2002-2013)

Background: Necrotizing fasciitis (NF) is a rare but aggressive infection that affects the superficial fascia and progressively destroys the tissue between the skin and underlying muscles. It is a surgical emergency with significant morbidity and mortality. This study aimed to explore the temporal and seasonal trends in NF infection in Qatar. Methods: A total of 327 patients diagnosed with NF, aged ≥ 18 years, and admitted to the Hamad General Hospital, Qatar, in 2002-2013 were retrospectively reviewed. The hospitalization and mortality rates in the general population in Qatar and the case fatality rate (CFR) were calculated for each year. The patients were grouped into summer, autumn, winter, and spring admissions based on their admission dates. Seasonality was studied by comparing the characteristics, bacteriological status, and outcomes of the patients admitted in different seasons. Results: The hospitalization rate of NF in Qatar was 2.9 per 100,000 population; in the study duration, this rate decreased from 2.8 to 1.6 per 100,000 population in 2002 and 2013, respectively. The mortality rate among NF cases increased from 1.9 to 3.6 per million population, and the CFR increased from 6.7 to 23 per 100 admissions in the same duration. No temporal trends in the hospitalization and mortality rates or CFR were evident in the study duration. Polybacterial infections were higher in autumn than in other seasons. Monobacterial Gram-positive infections were higher in spring than in other seasons, and monobacterial Gram-negative infections were higher in summer than in other seasons (p = 0.02). However, seasonality was not evident after further analysis in terms of species, severity, complications, length of hospital stays, and CFR in patients with NF. Conclusion: No clear trend or seasonality was observed in terms of outcomes; however, seasonality in NF-causing bacteria was evident, as polybacterial infections were significantly higher in autumn than in other seasons, whereas monobacterial infections were more frequent in spring and summer than in other seasons. However, the severity of infections, length of hospital stay, and mortality did not significantly vary. Further microbiological studies are needed to obtain confirmatory data regarding the temporal and seasonal trends of NF.

Expansion of Necrosis Depending on Hybrid Motor-Driven Motility of Aeromonas hydrophila in a Murine Wound Infection Model

The gram-negative bacterium Aeromonas hydrophila is a cause of fulminant and lethal necrotizing soft tissue infections (NSTIs). Suppressing the rapid proliferation of the pathogen and expansion of the necrosis caused in the host is an important issue in clinical practice, but the pathogenic mechanism for the rapid aggravation has not been clarified. In this study, we characterized the function of two types of motor stators in A. hydrophila and explored the role of motility during wound infection. In vitro analysis showed that the motility was reliably maintained while being complemented by the stators. We created a non-motile strain that lacked genes encoding two types of motor stators and analyzed the role of motility in a murine wound infection model. Examination of the bacterial burden in the local infection site and systemic circulation revealed that motility was not essential for the proliferation of A. hydrophila in the host. However, the extent of necrosis at the lesions was lower, and survival times were prolonged in mice infected with the non-motile strain compared with mice infected with the parent strain. These results provide evidence that the rapid expansion of necrosis and the progression to death within a short time period is dependent on the motility of A. hydrophila.