Severe skin and soft tissue infection in cohort patients admitted in a teaching hospital in Belgium: identification of risk factors for surgery

BACKGROUND

Necrotizing soft tissue infections (NSTIs) are associated with significant mortality if not promptly diagnosed and surgically treated.

AIM

This study aims to compare patients with severe skin and soft tissue infection treated with or without a surgical intervention and to identify risk factors that can predict the need for early surgery.

METHODS

Demographics, clinical, laboratory, Risk Indicator for Necrotizing Fasciitis (LRINEC) and imaging results were retrospectively collected.

RESULTS

There were 91 non-NSTI (group 1), 26 NSTI who were operated (group 2) and eight suspected NSTI who were not operated (group 3). In the multivariate analysis, skin necrosis, tachycardia, CRP value and hyperglycemia were predictive for surgery. A performance analysis revealed AUC of 0.65 (95%CI: 0.52-0.78) as to the LRINEC score for the use of surgery. The AUC for a predictive model associating four variables (heart rate, skin necrosis, CRP and glycemia at admission) was 0.71 (95%CI: 0.59-0.84). In terms of outcome, the median length of stay (LOS) was statistically higher in group 2 vs. group 1 (seven days (5-15) vs. 34 days (20-42), p < .001) and in group 2 vs. group 3 (34 days (20-42) vs. 14 days (11-19), p = .005). The overall in-hospital mortality at 30 days was 3.2% and did not statistically differ between the three groups.

CONCLUSIONS

Although the LRINEC score performed well in predicting surgery, the AUC of a model combining four predictive variables (glycemia, skin necrosis, CRP and heart rate) was superior. Further research is needed to validate this model.

A Comparison of the Application of Two Different Scoring Systems in a Patient With Upper Limb Necrotizing Fasciitis

Necrotizing fasciitis (NF) is a life-threatening soft-tissue infection that requires early recognition and surgical debridement to ensure the best outcome for patients. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score and the SIARI (Site other than lower limb, Immunosuppression, Age <60 years, Renal Impairment and Inflammatory markers) score are clinical predictor tools that can aid in the timely diagnosis of NF. This case report discusses a male patient who presented with a rash on his arm that was initially thought to be cellulitis. It examines how the application of scoring systems can be beneficial for earlier identification or when the diagnosis is uncertain.

Role of Procalcitonin for Early Discrimination Between Necrotizing Fasciitis and Cellulitis of the Extremities

Introduction Necrotizing fasciitis (NF) is a grave and life-threatening infection of the soft tissues. It is defined by the gradual necrosis of the fascia and subcutaneous tissue, which spreads along the fascial planes. Cellulitis, a prevalent skin infection, has led to suggestions that procalcitonin could serve as a diagnostic tool to distinguish it from other inflammatory skin conditions that resemble cellulitis. The study aims to assess the procalcitonin (PCT) levels in individuals with NF and cellulitis and determine its effectiveness in early differentiation between these two conditions. Methods After obtaining clearance from the institutional ethical committee, the study was conducted in the Department of General Surgery, Sri Devaraj Urs Medical College, over six months. Informed consent was obtained from all 30 patients included in this study. The study compared PCT levels in patients diagnosed with NF and cellulitis. Statistical analysis was performed using SPSS version 22 software (IBM Corp., Armonk, NY, USA). Results The mean age of subjects was 53.23 ± 8.78 years. Among patients, 21 (70%) were diagnosed with cellulitis and 9 (30%) were diagnosed with NF. The mean PCT levels were 0.34 ± 0.32 and 4.89 ± 1.98 among the cellulitis and NF groups, respectively. There was a significant difference (p<0.05). PCT had a sensitivity of 100% and a specificity of 100%, in differentiating cellulitis and necrotizing fasciitis. Conclusion PCT levels were notably elevated in cases of NF compared to cellulitis. Despite the study's limited sample size, it represents the first report highlighting the value of PCT as an early diagnostic tool for identifying necrotizing fasciitis.

Successful Outcome With a Multimodal Approach in the Management of Pediatric Necrotizing Fasciitis: A Report of a Rare Case

Necrotizing fasciitis is a commonly encountered modality by a practicing clinician which needs urgent and vigilant management. To decrease the potential morbidity and mortality of the pathology, an aggressive multimodal approach shows promising results. In our report, we present a case of a three-year-old male child who presented to us with the findings consistent with necrotizing fasciitis. The case report highlights the importance of multimodal approach in such a case.

Is the LRINEC score useful for predicting necrotizing fasciitis as a complication of MRONJ?

INTRODUCTION

Necrotizing fasciitis as a complication of medication-related osteonecrosis of the jaw (MRONJ), which we named "ONJ-NF", has been sometimes reported. This study aimed to investigate the usefulness of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score for predicting ONJ-NF.

MATERIALS AND METHODS

We included patients with acute MRONJ who required hospitalization at a single institution from April 2013 to June 2022. They were divided into two groups: patients with ONJ-NF and those with severe cellulitis as a complication of MRONJ, which we named "ONJ-SC." LRINEC scores were compared between the groups and the cut-off value of the score was set by creating a receiver operating characteristic curve.

RESULTS

Eight patients with ONJ-NF and 22 patients with ONJ-SC were included. The LRINEC score was significantly higher in patients with ONJ-NF (median: 8.0 points, range 6-10 points) than in those with ONJ-SC (median: 2.5 points, range 0-6 points). A LRINEC score of ≥ 6 points had a sensitivity of 100.0%, a specificity of 77.3%, and an area under the curve of 0.97. Among 6 parameters of LRINEC score, only C-reactive protein (CRP) and white blood cell count (WBC) had significant differences between two groups. Most of the patients with ONJ-NF were rescued by antibiotic therapy and surgical drainage including debridement of necrotic tissues, but unfortunately, one patient did not survive.

CONCLUSION

Our results suggested that the LRINEC score may be a useful diagnostic tool to predict ONJ-NF but valuating only CRP and WBC may be sufficient particularly in patients with osteoporosis.

The performance of clinical risk scores in the diagnosis of necrotising fasciitis

OBJECTIVE

Necrotising fasciitis (NF) is a quickly progressing and potentially life-threatening infection, involving the fascia and subcutaneous tissues. The diagnosis of this disease is challenging, especially due to a lack of specific clinical signs. In order to ensure a better and quicker identification of NF patients, a laboratory risk indicator score has been developed for NF (LRINEC). A variant has widened this score by adding clinical parameters (modified LRINEC). This study shows current outcomes of NF and compares the two scoring systems.

METHODS

This study was conducted between 2011 and 2018, and included patient demographics, clinical presentations, sites of infection, comorbidities, microbiological and laboratory findings, antibiotic therapies and LRINEC as well as modified LRINEC scores. The primary outcome was in-hospital mortality.

RESULTS

A cohort of 36 patients, diagnosed with NF, were included in this study. The mean hospital stay was 56 days (±38.2 days). The mortality rate in the cohort was 25%. The sensitivity of the LRINEC score was 86%. Calculation of the modified LRINEC score showed an improvement of the sensitivity to 97%. The average LRINEC score and modified LRINEC score for patients who died and who survived were equal (7.4 versus 7.9 and 10.4 versus 10.0, respectively).

CONCLUSION

The mortality rate of NF remains high. The modified LRINEC score increased the sensitivity in our cohort to 97%, and this scoring system could be supportive in the diagnosis of NF for early surgical debridement.

Prospective Validation and Comparison of Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) and Site Other Than Lower Limb, Immunosuppression, Age, Renal Impairment, and Inflammatory Markers (SIARI) Scoring Systems for Necrotizing Fasciitis

INTRODUCTION

Necrotizing fasciitis (NF) is a rapidly progressing infection of the soft tissues associated with high morbidity and mortality and hence it is a surgical emergency. Early diagnosis and treatment are of paramount importance. LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) and SIARI (Site other than lower limb, Immunosuppression, Age, Renal impairment, and Inflammatory markers) scoring systems have been established for early and accurate diagnosis of necrotizing fasciitis. This study compared the two scoring systems for diagnosing NF, predicting management, and elucidating the prognostic performance for re-operation and mortality.

METHODS

This prospective study was conducted in PGIMER Chandigarh, India, between February 2020 and June 2021. The study was approved by the Institutional Review Board (No. INT/IEC/2020-90). The clinical presentation, laboratory parameters, and imaging were used to classify patients into NF or severe cellulitis groups. We also calculated the LRINEC and SIARI scores. Demographic variables and mortality were recorded. The area under the receiver operating characteristic was used to express the accuracy of both scores at a cut-off LRINEC and SIARI scores of ≥6 and ≥ 4, respectively.

RESULTS

The study comprised 41 patients with NF and 11 with severe cellulitis. Informed written consent was taken from all the participants. At LRINEC score ≥6, the C-statistic for NF diagnosis was 0.839 (95% confidence interval [CI] 0.682-0.995, P 0.001), which was better than SIARI score at ≥ 4, C-statistic of 0.608 (95% CI 0.43-0.787, P 0.297). Both scores accurately predicted 30-day mortality. The LRINEC score showed a C-statistic of 0.912 (95% CI 0.798-1, P 0.001). Simultaneously, the SIARI score showed 70% sensitivity and 77% specificity, with a C-statistic of 0.805 (0.62-0.99, P = 0.017).

CONCLUSIONS

LRINEC score is an effective diagnostic tool for distinguishing necrotizing fasciitis from severe cellulitis. Additional research is required to establish the SIARI score's external validity.

The LRINEC Score-An Indicator for the Course and Prognosis of Necrotizing Fasciitis?

Background: The Laboratory Risk Indicator for Necrotizing Fasciitis score (LRINEC) is a simple tool used to support early diagnosis of Necrotizing Fasciitis (NF). The aim of this study was to investigate whether the LRINEC is suitable as a progression and prognosis parameter in patients with NF. Methods: In this retrospective study, laboratory data of 70 patients with NF were analyzed. The LRINEC was calculated for every patient at the time of hospital admission and postoperatively after surgical interventions. Furthermore, the LRINEC was examined as a prognostic factor for survival. Results: The overall lethality of our series was 20 out of 70 (28.6%). A highly significant LRINEC decrease was found for serial debridements. The largest decrease was observed after the first debridement. There was a significant difference between the initial LRINEC of deceased and surviving patients. A cut off value of >6.5 (7 LRINEC points) resulted in an optimal constellation of sensitivity (70%) and specificity (60%) to predict lethality in patients with NF. Conclusions: The LRINEC significantly decreases after surgical debridement. An initial LRINEC equal or greater than seven is an independent prognostic marker for lethality and can help to identify high-risk patients.

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.

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.

Differentiating Lower Extremity Necrotizing Soft Tissue Infection from Severe Cellulitis by Laboratory Parameters and Relevant History Points

Background

Necrotizing soft tissue infection (NSTI) of the lower extremity (LE) is a rapidly progressing infection that requires early diagnosis and prompt treatment to decrease risks of loss of limb or life. Clinical presentation, particularly of early NSTI, can appear similar to severe cellulitis. The purpose of this study is to identify factors that are associated with NSTI rather than severe cellulitis to differentiate patients with similar clinical presentation.

Methods

This retrospective cohort design study compares patients finally diagnosed with LE NSTI versus those diagnosed with severe cellulitis. Cohorts were matched using the modified Laboratory Risk Indicator for Necrotizing Fasciitis (m-LRINEC) score in the setting of LE soft tissue infection. Laboratory values, vital signs, subjective symptoms, and social factors including substance abuse were recorded. Univariate and multivariate analyses were performed.

Results

Multivariate statistical analysis and clinical interpretation of data identified four factors more associated with a diagnosis of NSTI than severe cellulitis: elevated lactate, a patient-reported history of fever, male gender, and intravenous substance user.

Conclusion

In patients with lower extremity infections, the clinical presentation of NSTI and severe cellulitis may appear similar. In this retrospective cohort of patients matched with m-LRINEC scores, elevated lactate, subjective fever, male gender, and intravenous substance abuser were significantly associated with NSTI rather than severe cellulitis. Further studies of these factors in the clinical setting can help tailor the differential diagnosis in the care of patients with severe lower extremity infections. Matched with m-LRINEC scores, elevated lactate, subjective fever, male gender, and intravenous substance abuser were significantly associated with NSTI rather than severe cellulitis. Further studies of these factors in the clinical setting can help tailor the differential diagnosis in the care of patients with severe lower extremity infections.

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.

Necrotizing fasciitis: Usefulness of the LRINEC score in a third-level hospital

AIM

To review patients seen in the emergency room, diagnosed with necrotizing fasciitis (NF) and the correlation of such complications with the Laboratory Risk Indicator for Necrotizing fasciitis scale (LRINEC). The purpose of this study is to assess the use of the LRINEC score for early diagnosis of NF and its prognostic use in a consecutive series of cases treated at our hospital.

METHODS

Retrospective observational study including patients with a diagnosis of NF in the emergency room of a tertiary hospital over 11 years. The results are shown as median, interquartile range and absolute range for quantitative variables. In the case of qualitative variables, the results are shown as absolute and relative frequency. The comparison between the categories of the LRINEC scale was performed through a post-hoc comparison from a non-parametric rank-ANOVA analysis. Comparisons between LRINEC groups in the qualitative variables were performed using Fisher's exact test.

RESULTS

A total of 45 patients with a mean age of 51 years were identified. There was a 20% mortality rate (9 cases). The highest mortality rate was registered in the high-risk group (LRINEC greater than 8) with 4 deceased individuals (44.44%), while in the low and moderate-risk groups, 3 and 2 deceased individuals (33% and 22%) were registered, respectively, without considering this result statistically significant (p=0.811). There was an amputation rate of 15.6% (7 cases). The average LRINEC score was greater in the cases that required amputation 9 (95% CI 7; 13) in comparison to the other patients, 6 (95% CI 5; 8), p=0.044. The average hospital stay lasted 32.5 days (95% CI: 25; 40); 30 days in the low-risk group, 41 days in the moderate-risk group and 40 days in the high-risk group. Mortality was associated to a smaller number of interventions (p=0.005) and was preceded by septic shock in all cases.

CONCLUSIONS

The LRINEC score may be useful to aid diagnosis. However, clinical suspicion is the most important in diagnosis. A LRINEC low score does not exclude NF. In this retrospective series, 35.71% of cases presented a low LRINEC score, making the rate of false negatives high. In view of these results, The LRINEC score cannot be used as a prognostic value since an initial low score does not rule out serious evolution.

Modified Laboratory Risk Indicator for Necrotizing Fasciitis (m-LRINEC) Score System in Diagnosing Necrotizing Fasciitis: A Nested Case-Control Study

Aim

This study aims to present a modified Laboratory Risk Indicator for Necrotizing Fasciitis (m-LRINEC) scoring system and to evaluate its ability in discriminating necrotizing fasciitis (NF) from other severe soft-tissue infections.

Methods

Patients with NF diagnosed by surgical findings in our institution between January 2014 and December 2020 were included as the case group, matched by controls with severe soft-tissue infections other than NF in a ratio of 2:1, based on demographics, calendar time and immunosuppressant status. Patients’ demographics, comorbidities and laboratory test results were extracted from medical records. Logistic regression analyses were used to determine the association with NF after adjustment for confounders, whereby m-LRINEC was developed. Receiver operating characteristics (ROC) curves and the area under the curve (AUC) were used to evaluate its discriminating ability.

Results

There were 177 patients included, 59 in the NF group and 118 in the non-NF group. We added comorbid diabetes and kidney disease to the original LRINEC scoring system, used high-sensitivity C-reactive protein (HCRP) to replace the CRP and redefined the cut-off values for the other four variables, to develop the m-LRINEC system. The cut-off value for m-LRINEC was 17 points, with corresponding sensitivity of 93.2% and specificity of 86.9%, and the AUC was 0.935 (95% CI 0.892 to 0.977; p<0.001).

Conclusion

The m-LRINEC scoring system shows a high sensitivity and specificity in discriminating NF from other severe soft-tissue infections. Patients with an m-LRINEC score of >17 points should have a high index of suspicion for the presence of NF. The validity of the m-LRINEC needs to be confirmed in studies with larger samples and better design.

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 Soft Tissue Infections in Intensive Care

Background:

Necrotizing soft tissue infections (NSTIs) are typically characterized by extensive soft tissue destruction with systemic signs of toxicity, ranging from sepsis to septic shock. Our aim was to analyze the clinical characteristics, microbiological results, laboratory data, therapies, and outcome of patients with NSTIs admitted to an intensive care unit (ICU).

Methods:

A monocentric observational study of patients admitted to the ICU of a university hospital between January 2009 and December 2017. The demographic characteristics, comorbidities, clinical features, microbiology and laboratory results, organ dysfunctions, therapies, and outcome were retrospectively analyzed.

Results:

There were 59 patients and 70% males. The mean age (± SD) was 55 ± 18; type II (monomicrobial) NSTI was present in 36 patients (61%); the most common isolated pathogen was Streptococcus pyogenes in 28 patients (48%). Septic shock was diagnosed in 41 patients (70%). The most common organ dysfunctions were circulatory and renal in 42 (71%) and 38 patients (64%). The mean value (± SD) of serum lactate at admission to the ICU was 4.22 ± 5.42 mmol/l, the median SOFA score and SAPS II were 7 (IQR 4 - 10) and 46 (IQR 30.5 - 53). ICU mortality rate was 25%. Both SOFA score and serum lactate demonstrated a good prognostic value regarding ICU outcome (OR 1.29, 95%CI 1.07-1.57, P < 0.007 and OR 1.53, 95%CI 1.19-1.98, P < 0.001). A cut-off value for serum lactate of 6.55 mmol/L positively predicted mortality with 67% sensitivity and 97% specificity.

Conclusion:

NSTIs carry a high risk of septic shock and multiple organ dysfunction syndrome and thus are still associated with high mortality. In our study, the value of serum lactate at admission to the ICU correlated well with mortality. This easy-to-measure parameter could play a role in the decision-making process regarding prognosis and continuation of care.

Necrotizing Soft Tissue Infections

Necrotizing soft tissue infections occur after traumatic injuries, minor skin lesions, nonpenetrating injuries, natural childbirth, and in postsurgical and immunocompromised patients. Infections can be severe, rapidly progressive, and life threatening. Survivors often endure multiple surgeries and prolonged hospitalization and rehabilitation. Despite subtle nuances that may distinguish one entity from another, clinical approaches to diagnosis and treatment are highly similar. This review describes the clinical and laboratory features of necrotizing soft tissue infections and addresses recommended diagnostic and treatment modalities. It discusses the impact of delays in surgical debridement, antibiotic use, and resuscitation on mortality, and summarizes key pathogenic mechanisms.

Utility of Magnetic Resonance Imaging for Differentiating Necrotizing Fasciitis from Severe Cellulitis: A Magnetic Resonance Indicator for Necrotizing Fasciitis (MRINEC) Algorithm

We developed a new magnetic resonance indicator for necrotizing fasciitis (MRINEC) algorithm for differentiating necrotizing fasciitis (NF) from severe cellulitis (SC). All adults with suspected NF between 2010 and 2018 in a tertiary hospital in South Korea were enrolled. Sixty-one patients were diagnosed with NF and 28 with SC. Among them, 34 with NF and 15 with SC underwent magnetic resonance imaging (MRI). The MRINEC algorithm, a two-step decision tree including T2 hyperintensity of intermuscular deep fascia and diffuse T2 hyperintensity of deep peripheral fascia, diagnosed NF with 94% sensitivity (95% confidence interval (CI), 80–99%) and 60% specificity (95% CI, 32–84%). The algorithm accurately diagnosed all 15 NF patients with a high (≥8) laboratory risk indicator for necrotizing fasciitis (LRINEC) score. Among the five patients with an intermediate (6–7) LRINEC score, sensitivity and specificity were 100% (95% CI, 78–100%) and 0% (95% CI, 0–84%), respectively. Finally, among the 29 patients with a low (≤5) LRINEC score, the algorithm had a sensitivity and specificity of 88% (95% CI, 62–98%) and 69% (95% CI, 39–91%), respectively. The MRINEC algorithm may be a useful adjuvant method for diagnosing NF, especially when NF is suspected in patients with a low LRINEC score.

Subcutaneous emphysema or necrotizing fasciitis after insect bite?

Background

The rapid form of subcutaneous emphysema after an insect bite is hard to distinguish from necrotizing fasciitis.

Case presentation

Here we report a case of benign subcutaneous emphysema after an insect bite on the hand of an 18-year-old Caucasian man. The puncture area in the first web space of his hand was erythematous and swollen. After 4 h, he began to hear crackling sounds in the hand. Although conservative management was provided, he experienced gradually increasing pain and rapid progression in swelling and crepitation. The symptoms regressed after fasciotomy.

Conclusion

This is the fourth reported case of benign subcutaneous emphysema after an insect bite in the literature. Although benign emphysema has a good prognosis after treatment, it is similar to necrotizing fasciitis. Proper diagnosis can only be established with histological and microbiological investigations, but in cases where early histological and microbiological investigations cannot be performed, biochemistry and radiological test should be used.

What Demographic and Clinical Factors Are Associated with In-hospital Mortality in Patients with Necrotizing Fasciitis?

BACKGROUND

Necrotizing fasciitis is a rare infection with rapid deterioration and a high mortality rate. Factors associated with in-hospital mortality have not been thoroughly evaluated. Although predictive models identifying the diagnosis of necrotizing fasciitis have been described (such as the Laboratory Risk Indicator for Necrotizing Fasciitis [LRINEC]), their use in predicting mortality is limited.

QUESTIONS/PURPOSES

(1) What demographic factors are associated with in-hospital mortality in patients with necrotizing fasciitis? (2) What clinical factors are associated with in-hospital mortality? (3) What laboratory values are associated with in-hospital mortality? (4) Is the LRINEC score useful in predicting mortality?

METHODS

We retrospectively studied all patients with necrotizing fasciitis at our tertiary care institution during a 10-year period. In all, 134 patients were identified; after filtering out patients with missing data (seven) and those without histologically confirmed necrotizing fasciitis (12), 115 patients remained. These patients were treated with early-initiation antibiotic therapy and aggressive surgical intervention once the diagnosis was suspected. Demographic data, clinical features, laboratory results, and treatment variables were identified. The median age was 56 years and 42% of patients were female. Of the 115 patients analyzed, 15% (17) died in the hospital. Univariate and receiver operating characteristic analyses were performed due to the low number of mortality events seen in this cohort.

RESULTS

The demographic factors associated with in-hospital mortality were older age (median: 64 years for nonsurvivors [interquartile range (IQR) 57-79] versus 55 years for survivors [IQR 45-63]; p = 0.002), coronary artery disease (odds ratio 4.56 [95% confidence interval (CI) 1.51 to 14]; p = 0.008), chronic kidney disease (OR 4.92 [95% CI 1.62 to 15]; p = 0.006), and transfer from an outside hospital (OR 3.47 [95% CI 1.19 to 10]; p = 0.02). The presenting clinical characteristics associated with in-hospital mortality were positive initial blood culture results (OR 4.76 [95% CI 1.59 to 15]; p = 0.01), lactic acidosis (OR 4.33 [95% CI 1.42 to 16]; p = 0.02), and multiple organ dysfunction syndrome (OR 6.37 [95% CI 2.05 to 20]; p = 0.002). Laboratory values at initial presentation that were associated with in-hospital mortality were platelet count (difference of medians -136 [95% CI -203 to -70]; p < 0.001), serum pH (difference of medians -0.13 [95% CI -0.21 to -0.03]; p = 0.02), serum lactate (difference of medians 0.90 [95% CI 0.40 to 4.80]; p < 0.001), serum creatinine (difference of medians 1.93 [95% CI 0.65 to 3.44]; p < 0.001), partial thromboplastin time (difference of medians 8.30 [95% CI 1.85 to 13]; p = 0.03), and international normalized ratio (difference of medians 0.1 [95% CI 0.0 to 0.5]; p = 0.004). The LRINEC score was a poor predictor of mortality with an area under the receiver operating characteristics curve of 0.56 [95% CI 0.45-0.67].

CONCLUSIONS

Factors aiding clinical recognition of necrotizing fasciitis are not consistently helpful in predicting mortality of this infection. Identifying patients with potentially compromised organ function should lead to aggressive and expedited measures for diagnosis and treatment. Future multicenter studies with larger populations and a standardized algorithm of treatment triggered by high clinical suspicion can be used to validate these findings to better help prognosticate this potentially fatal diagnosis.Level of Evidence Level III, therapeutic study.

Prospective Validation of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) Score for Necrotizing Fasciitis of the Extremities

OBJECTIVES

The Laboratory Risk Indicator for Necrotizing Fasciitis score was developed as a clinical decision tool for distinguishing necrotizing fasciitis from other soft tissue infections. We prospectively evaluated the performance of the Laboratory Risk Indicator for Necrotizing Fasciitis score for the diagnosis of patients with necrotizing fasciitis in the extremities.

METHODS

We conducted a prospective and observational cohort study of emergency department patients with necrotizing fasciitis or severe cellulitis in the extremities between April 2015 and December 2016. The Laboratory Risk Indicator for Necrotizing Fasciitis score was calculated for every enrolled patient. The sensitivity, specificity, positive predictive value, and negative predictive value of cut-off scores of 6 and 8 were evaluated. The accuracy of the Laboratory Risk Indicator for Necrotizing Fasciitis score was expressed as the area under the receiver operating characteristic curve.

RESULTS

A total of 106 patients with necrotizing fasciitis and 825 patients with cellulitis were included. With an Laboratory Risk Indicator for Necrotizing Fasciitis cut-off score ≥6, the sensitivity was 43% (95% confidence interval 34% to 53%), specificity was 83% (95% confidence interval 80% to 86%), positive predictive value was 25% (95% confidence interval 20% to 30%), and negative predictive value was 92% (95% confidence interval 91% to 93%); with an Laboratory Risk Indicator for Necrotizing Fasciitis cut-off score ≥8, the sensitivity was 27% (95% confidence interval 19% to 37%), specificity was 93% (95% confidence interval 91% to 94%), positive predictive value was 33% (95% confidence interval 25% to 42%), and negative predictive value was 91% (95% confidence interval 90% to 92%). The area under the receiver operating characteristic curve for accuracy of the Laboratory Risk Indicator for Necrotizing Fasciitis score was 0.696 (95% CI 0.640 to 0.751).

CONCLUSION

The Laboratory Risk Indicator for Necrotizing Fasciitis score may not be an accurate tool for necrotizing fasciitis risk stratification and differentiation between severe cellulitis and necrotizing fasciitis in the emergency department setting based on our study.

Usefulness of a risk scale based on procalcitonin for early discrimination between necrotising fasciitis and cellulitis of the extremities

BACKGROUND AND OBJECTIVE

To assess the usefulness of a risk scale based on serum procalcitonin (PCT) compared to the Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) scale in the early discrimination between necrotising fasciitis (NF) and cellulitis of the extremities.

MATERIALS AND METHODS

Retrospective study of consecutive patients with confirmed diagnosis of NF in one limb (n=11). This study group was compared with 23 consecutive patients with a diagnosis of severe limbs cellulitis during the same period. The clinical data and laboratory parameters were analysed, the main variable was the serum level of PCT upon admission. The capacity for NF diagnosis of the two methods, PCT level and LRINEC scale score, were evaluated by ROC curve and determined by the calculation of the area under the curve (AUC).

RESULTS

The AUC was significantly higher with PCT measurement, both as a continuous variable and when the risk was categorised. The cut-off point for the PCT level with the highest AUC under the curve was from 0.87ng/ml (sensitivity 90.9%, specificity 82.6%), whereas it was a score of 5 on the LRINEC scale (sensitivity 72.7%, specificity 82.6%).

CONCLUSION

PCT measurement was a more effective method than the LRINEC score for early discrimination between NF and cellulitis of the extremities. A low level of PCT, associated with the patient's clinical status and physical examination is especially useful to rule out an early diagnosis of NF.

Necrotizing Soft Tissue Infection: Diagnostic Accuracy of Physical Examination, Imaging, and LRINEC Score: A Systematic Review and Meta-Analysis

OBJECTIVE

We sought to summarize accuracy of physical examination, imaging, and Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score in diagnosis of necrotizing soft tissue infection (NSTI) in adults with a soft tissue infection clinically concerning for NSTI.

SUMMARY OF BACKGROUND DATA

NSTI is a life-threatening diagnosis. Delay to diagnosis and surgical management is associated with increased mortality.

METHODS

We searched 6 databases from inception through November 2017. We included English-language studies reporting diagnostic accuracy of testing or LRINEC Score. Outcome was NSTI confirmed by surgery or histopathology. Two reviewers screened all citations and extracted data independently. Summary measures were obtained from the Hierarchical Summary Receiver Operating Characteristic model.

RESULTS

From 2,290 citations, we included 23 studies (n = 5982). Of physical examination signs, pooled sensitivity and specificity for fever was 46.0% and 77.0% respectively, for hemorrhagic bullae 25.2% and 95.8%, and for hypotension 21.0% and 97.7%. Computed tomography (CT) had sensitivity of 88.5% and specificity of 93.3%, while plain radiography had sensitivity of 48.9% and specificity of 94.0%. Finally, LRINEC ≥ 6 had sensitivity of 68.2% and specificity of 84.8%, while LRINEC ≥ 8 had sensitivity of 40.8% and specificity of 94.9%.

CONCLUSIONS

Absence of any 1 physical examination feature (eg, fever or hypotension) is not sufficient to rule-out NSTI. CT is superior to plain radiography. LRINEC had poor sensitivity, and should not be used to rule-out NSTI. Given the poor sensitivity of these tests, a high clinical suspicion warrants early surgical consultation for definitive diagnosis and management.

Necrotizing Soft Tissue Infections: A Focused Review of Pathophysiology, Diagnosis, Operative Management, Antimicrobial Therapy, and Pediatrics

Background: Necrotizing fasciitis is a major health problem throughout the world. The purpose of this review is to assist providers with the care of these patients through a better understanding of the pathophysiology and management options. Methods: This is a collaborative review of the literature between members of the Surgical Infection Society of North America and World Society of Emergency Surgery. Results: Necrotizing fasciitis continues to be difficult to manage with the mainstay being early diagnosis and surgical intervention. Recognition of at-risk populations assists with the initiation of treatment, thereby impacting outcomes. Conclusions: Although there are some additional treatment strategies available, surgical debridement and antimicrobial therapy are central to the successful eradication of the disease process.

The SIARI Score: A Novel Decision Support Tool Outperforms LRINEC Score in Necrotizing Fasciitis

BACKGROUND

The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) scoring system was developed to aid the diagnosis of necrotizing fasciitis and guide management [1].

AIM

To validate the LRINEC score and identify clinical predictors to develop a refined diagnostic scoring tool for the diagnosis of necrotizing fasciitis at Middlemore Hospital, New Zealand.

METHODS

This was a retrospective case-control study of patients admitted to Middlemore Hospital with necrotizing fasciitis and severe cellulitis between January 2000 and December 2010. The LRINEC scores at admission were evaluated for performance in discriminating between cases of necrotizing fasciitis and severe cellulitis. Cases and controls were randomized into developmental and validation cohorts. Univariate and multivariate logistic regression analysis of demographic, clinical, and laboratory variables for the diagnosis of necrotizing fasciitis was performed. The identified independent predictors were used to develop a new diagnostic scoring tool.

RESULTS

The area under the receiver operating characteristic curve (C-statistic) of a LRINEC score ≥6 for the diagnosis of necrotizing fasciitis was 0.679. The newly developed SIARI score [Site other than the lower limb, Immunosuppression, Age < 60 years, Renal impairment (creatinine > 141), and Inflammatory markers (CRP ≥ 150, WCC > 25] demonstrated superior diagnostic ability compared with the LRINEC score in both the developmental (C-statistic: 0.832 vs. 0.691, p < 0.001) and validation cohorts (C-statistic: 0.847 vs. 0.667, p < 0.001).

CONCLUSION

The LRINEC score exhibited only modest discriminative performance in this cohort, while the SIARI score is a simplified tool that demonstrates superior diagnostic ability for detecting necrotizing fasciitis. Future external validation studies are required to confirm the trends observed in this study.

A case of streptococcus necrotizing fasciitis secondary to acute tonsillitis and review of literatures

Necrotizing fasciitis, officially named by Wilson in 1952, was a rare potentially life-threatening necrotizing soft tissue infections disease. The main lesions showed subcutaneous fat and fascia layer in progressive necrosis, generally not involving muscles. It was characterized by acute onset, rapid progress, and dangerous condition, often accompanied by systemic toxin shock, which was a relatively rare clinical acute critical disease with high mortality rate. Necrotizing fasciitis is a rare but clinical critical disease. The overall incidence of necrotizing fasciitis is approximately 0.04 cases per 1000 persons in the United States, the 30-day mortality is 27%, and necrotizing fasciitis–related mortality in Asian region is about 28%. Streptococcus pyogenes (group A streptococcus) are human-specific pathogens that can cause upper respiratory tract infection such as tonsillitis, associated with post-infection diseases such as rheumatic fever, and also can induce severe invasive diseases such as necrotizing fasciitis and streptococcus toxin shock syndrome. This article reports a case of streptococcus necrotizing fasciitis secondary to suppurative tonsillitis, which was seldom reported before and our successful management with delayed debridement. This study was anonymous and was approved by the local Research Ethics Committee. Informed consent was obtained from the patient.

Necrotizing skin and soft-tissue infections in the intensive care unit

BACKGROUND

Necrotizing skin and soft-tissue infections (NSTI) are rare but potentially life-threatening and disabling infections that often require intensive care unit admission.

OBJECTIVES

To review all aspects of care for a critically ill individual with NSTI.

SOURCES

Literature search using Medline and Cochrane library, multidisciplinary panel of experts.

CONTENT

The initial presentation of a patient with NSTI can be misleading, as features of severe systemic toxicity can obscure sometimes less impressive skin findings. The infection can spread rapidly, and delayed surgery worsens prognosis, hence there is a limited role for additional imaging in the critically ill patient. Also, the utility of clinical scores is contested. Prompt surgery with aggressive debridement of necrotic tissue is required for source control and allows for microbiological sampling. Also, prompt administration of broad-spectrum antimicrobial therapy is warranted, with the addition of clindamycin for its effect on toxin production, both in empirical therapy, and in targeted therapy for monomicrobial group A streptococcal and clostridial NSTI. The role of immunoglobulins and hyperbaric oxygen therapy remains controversial.

IMPLICATIONS

Close collaboration between intensive care, surgery, microbiology and infectious diseases, and centralization of care is fundamental in the approach to the severely ill patient with NSTI. As many aspects of management of these rare infections are supported by low-quality data only, multicentre trials are urgently needed.

A Systematic Review of the Laboratory Risk Indicator for Necrotizing Fasciitis Score and Its Utility in Orthopedics for Diagnosing Necrotizing Fasciitis in Adults

Given its association with trauma and surgery, necrotizing fasciitis is a disease orthopedists are likely to encounter. The laboratory risk indicator for necrotizing fasciitis score is an adjunct diagnostic test designed to help diagnose early necrotizing fasciitis infections, but studies evaluating the scoring system have reported conflicting results. The purpose of this systematic review was to provide clarity on the laboratory risk indicator for necrotizing fasciitis score's capabilities and when it is best used. [Orthopedics. 2019; 42(3):e288-e294.].

Distinguishing necrotizing from non-necrotizing fasciitis: a new predictive scoring integrating MRI in the LRINEC score

OBJECTIVES

To develop and validate a scoring system integrating MRI and laboratory findings to differentiate necrotizing fasciitis (NF) from non-necrotizing fasciitis (non-NF).

METHODS

This retrospective study included 144 subjects who underwent surgery in one of three tertiary referral centers for NF or cellulitis with non-NF. The development cohort consisted of 96 subjects (NF = 47; non-NF = 49) from one center, and the validation cohort consisted of 48 subjects (NF = 23; cellulitis with non-NF = 25) from two different centers. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) scoring system and five MRI findings (thickening of the intermuscular deep fascia ≥ 3 mm, extensive involvement of the deep fascia, multi-compartmental involvement in one extremity, presence of gas, and contrast-enhancement pattern) were included in univariate and multivariate logistic regression analysis to identify independent predictors of NF. An additive scoring system was developed using the coefficients of the final regression model. Model performance was assessed for discrimination and calibration. The scoring system was externally validated.

RESULT

The final scoring system consisted of three variables: thickening of the deep fascia ≥ 3 mm, multi-compartmental involvement, and LRINEC score. The new predictive model showed improved performance (area under the receiver operating characteristic curve [AUC], 0.862; positive and negative predictive values, 82% and 79%, respectively), compared with the LRINEC score alone (0.814, 77% and 67%, respectively). The model also showed good discrimination with the external validation dataset (AUC, 0.933).

CONCLUSIONS

Differentiation of NF from severe cellulitis with non-NF can be achieved with the new predictive scoring system.

KEY POINTS

• The new predictive scoring system integrating two MRI findings with the LRINEC score can help in the differentiation of necrotizing fasciitis from severe cellulitis with non-necrotizing fasciitis. • Thickening of the deep fascia ≥ 3 mm and multi-compartmental involvement were the most important MRI findings for the differentiation.

Chance to cut: defining a negative exploration rate in patients with suspected necrotizing soft tissue infection

Background

Necrotizing soft tissue infections (NSTI) are aggressive infections associated with significant morbidity and mortality. Despite multiple predictive models for the identification of NSTI, a subset of patients will not have an NSTI at the time of surgical exploration. We hypothesized there is a subset of patients without NSTI who are clinically indistinguishable from those with NSTI. We aimed to characterize the differences between NSTI and non-NSTI patients and describe a negative exploration rate for this disease process.

Methods

We conducted a retrospective review of adult patients undergoing surgical exploration for suspected NSTI at our county-funded, academic-affiliated medical center between 2008 and 2015. Patients were identified as having NSTI or not (non-NSTI) based on surgical findings at the initial operation. Pathology reports were reviewed to confirm diagnosis. The NSTI and non-NSTI patients were compared using χ² test, Fisher's exact test, and Wilcoxon rank-sum test as appropriate. A p value <0.05 was considered significant.

Results

Of 295 patients undergoing operation for suspected NSTI, 232 (79%) were diagnosed with NSTI at the initial operation and 63 (21%) were not. Of these 63 patients, 5 (7.9%) had an abscess and 58 (92%) had cellulitis resulting in a total of 237 patients (80%) with a surgical disease process. Patients with NSTI had higher white cell counts (18.5 vs. 14.9 k/mm³, p=0.02) and glucose levels (244 vs. 114 mg/dL, p<0.0001), but lower sodium values (130 vs. 134 mmol/L, p≤0.0001) and less violaceous skin changes (9.2% vs. 23.8%, p=0.004). Eight patients (14%) initially diagnosed with cellulitis had an NSTI diagnosed on return to the operating room for failure to improve.

Conclusions

Clinical differences between NSTI and non-NSTI patients are subtle. We found a 20% negative exploration rate for suspected NSTI. Close postoperative attention to this cohort is warranted as a small subset may progress.

Level of evidence

Retrospective cohort study, level III.

Necrotizing Soft Tissue Infections in the Vasculopathic Patient: Review of Literature

Background:

Necrotizing soft tissue infection is a surgical emergency associated with high mortality. Its presence in patients with risk factors for peripheral arterial disease such as diabetes mellitus is consistently associated with significantly poorer outcomes. Though it has been over a century since it was initially described in the literature, mortality rates remain high and treatment regimens are not standardized.

Materials and methods:

PubMed and Cochrane databases were searched for articles pertaining to necrotizing soft tissue infections. Articles were screened for relevance with the intent to compare outcomes in prospective studies of patients with diabetes mellitus or peripheral arterial disease. Patient demographics, clinical findings, mortality, rates of amputation, and morbidity were intended to be compared.

Results:

857 articles were identified, 165 duplicates were removed, and 6 prospective trials were identified for inclusion. Due to significant paucity of data, patient heterogeneity, and lack of standardization for surgical management, a descriptive review of the literature in relation to necrotizing soft tissue infections was pursued, with a focus on high-risk patients with peripheral arterial disease or diabetes mellitus.

Conclusions:

Early aggressive surgical intervention or major amputation may reduce mortality at the cost of increased disability and poorer quality of life in the long term, and may be appropriate in vasculopaths with poorly controlled diabetes and rapidly progressive fulminant infection. However, there is a deficiency in high-level evidence supporting surgical decision-making in this setting, with no standardized protocols for amputation. Future research will be needed to clarify the patient population who would benefit from radical amputation versus intention for limb salvage.

Presenting features of extremity necrotizing fasciitis in the pediatric patient: a case-control analysis

This analysis sought to develop a tool for early differentiation between pediatric necrotizing fasciitis (NF) of the extremity and more benign infection. All diagnoses of extremity NF, cellulitis, and abscess from a single institution from 2009 to 2015 were included. Vitals and laboratory values were compared between cohorts using analysis of variance and decision tree analysis. NF was associated with thrombocytopenia, hyperthermia, tachycardia, and tachypnea. Decision tree analysis identified C-reactive protein more than 7.0 to be 100% sensitive and 95.7% specific for differentiating NF from cellulitis or abscess. The results offer quantitative support for clinical suspicion of NF in the evaluation of pediatric extremity infection.

The Role of Computed Tomography in the Diagnosis of Necrotizing Soft Tissue Infections

BACKGROUND

The exact role of IV contrast-enhanced computed tomography (CT) in the diagnosis of necrotizing soft tissue infections (NSTIs) has not yet been established. We aimed to explore the role of CT in patients with clinical suspicion of NSTI and assess its sensitivity and specificity for NSTI.

METHODS

The medical records of patients admitted between 2009 and 2016, who received IV contrast-enhanced CT to rule out NSTI, were reviewed. CT was considered positive in case of: (a) gas in soft tissues, (b) multiple fluid collections, (c) absence or heterogeneity of tissue enhancement by the IV contrast, and (d) significant inflammatory changes under the fascia. NSTI was confirmed only by the presence of necrotic tissue during surgical exploration. NSTI was considered absent if surgical exploration failed to identify necrosis, or if the patient was successfully treated non-operatively.

RESULTS

Of the 184 patients, 17 had a positive CT and hence underwent surgical exploration with NSTI being confirmed in 13 of them (76%). Of the 167 patients that had a negative CT, 38 (23%) underwent surgical exploration due to the high clinical suspicion for NSTI and were all found to have non-necrotizing infections; the remaining 129 (77%) were managed non-operatively with successful resolution of symptoms. The sensitivity of CT in identifying NSTI was 100%, the specificity 98%, the positive predictive value 76%, and the negative predictive value 100%.

CONCLUSIONS

A negative IV contrast-enhanced CT scan can reliably rule out the need for surgical intervention in patients with initial suspicion of NSTI.

Retroperitoneal Necrotizing Fasciitis from Fournier's Gangrene in an Immunocompromised Patient

INTRODUCTION

Necrotizing fasciitis (NF) is a devastating soft tissue disease causing fulminant clinical deterioration, and extension into the retroperitoneum has a high mortality rate. This disease process demands a strong clinical suspicion for early identification which must be coupled with frequent wide surgical debridements and intravenous antibiotics for improved outcomes. Various clinical risk factors may render a weakness in the patient's immune status including diabetes mellitus, chronic renal failure, obesity, and autoimmune disorders, such as a human immunodeficiency virus (HIV) infection.

CASE REPORT

A 55-year-old male presented with hypotension requiring a large intravenous fluid resuscitation and vasopressors. He was diagnosed with the human immunodeficiency virus upon presentation. A computerized tomographic scan revealed air and fluid in the perineum and pelvis, ascending into the retroperitoneum. Multiple surgical debridements to his perineum, deep pelvic structures, and retroperitoneum were completed. After colostomy placement, antibiotic administration, and wound care, he was closed using split-thickness skin grafting.

CONCLUSION

NF is a sinister and fulminant disease requiring prompt diagnosis and surgical intervention. The best chance for survival occurs with emergent surgical debridement and appropriate intravenous antibiotics. While retroperitoneal NF is consistent with uniformly poor outcomes, patients are best treated in an American Burn Association-verified burn center.

Necrotising fasciitis: a ticking time bomb?

Necrotising fasciitis (NF) is a destructive bacterial infection and has often been described in media reports as a 'flesh-eating disease', which if diagnosed late is associated with worse outcome. Unfortunately, diagnosing NF is difficult due to the similar presentation of NF compared with other types of skin and soft tissue infections. The early presentation of NF only shows tenderness, swelling, erythema and warm skin. Moreover, NF is normally accompanied with aberrant laboratory findings, mainly elevated C reactive protein (CRP) levels. In this case report we evaluate the diagnostic process of a patient with NF without aberrant infection parameters; both normal levels of CRP and white blood cell count were seen.

Necrotizing fasciitis attended in the Emergency Department in a tertiary Hospital: Evaluation of the LRINEC scale

AIM

To describe mortality and complications of patients seen in the emergency room, diagnosed with necrotizing soft tissue infection (NSTI) and the correlation of such complications with the Laboratory Risk Indicator for Necrotizing fasciitis scale (LRINEC).

METHODS

Retrospective observational study including patients with a diagnosis of NSTI in the emergency room of a tertiary hospital over 7 years. The results are shown as median, interquartile range and absolute range for quantitative variables. In the case of qualitative variables, the results are shown as absolute and relative frequency. The comparison between the categories of the LRINEC scale was performed through a post-hoc comparison from a non-parametric ANOVA analysis. Comparisons between LRINEC groups in the qualitative variables were performed using Fisher's Exact test.

RESULTS

24 patients with a mean age of 51.9 years were identified. The LRINEC scale was used on 21 patients: in 10, the value indicated low risk (<6), in 4 it indicated intermediate risk (6 or 7) and in 7 it indicated high risk (≥8). The amputation rate in patients with low, intermediate and high risk was 10%, 25% and 66% respectively with a mortality of 4.2%. There was an increase in hospital stay between the low and high level of the scale (p=0,007).

CONCLUSIONS

In general, a change in the prognosis between the medium and high levels of the LRINEC scale could not be recorded, but was recorded in hospital stay between the low and the high level, practically tripling the median of days of hospital stay.

Evaluating the Laboratory Risk Indicator to Differentiate Cellulitis from Necrotizing Fasciitis in the Emergency Department

INTRODUCTION

Necrotizing fasciitis (NF) is an uncommon but rapidly progressive infection that results in gross morbidity and mortality if not treated in its early stages. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score is used to distinguish NF from other soft tissue infections such as cellulitis or abscess. This study analyzed the ability of the LRINEC score to accurately rule out NF in patients who were confirmed to have cellulitis, as well as the capability to differentiate cellulitis from NF.

METHODS

This was a 10-year retrospective chart-review study that included emergency department (ED) patients ≥18 years old with a diagnosis of cellulitis or NF. We calculated a LRINEC score ranging from 0-13 for each patient with all pertinent laboratory values. Three categories were developed per the original LRINEC score guidelines denoting NF risk stratification: high risk (LRINEC score ≥8), moderate risk (LRINEC score 6-7), and low risk (LRINEC score ≤5). All cases missing laboratory values were due to the absence of a C-reactive protein (CRP) value. Since the score for a negative or positive CRP value for the LRINEC score was 0 or 4 respectively, a LRINEC score of 0 or 1 without a CRP value would have placed the patient in the "low risk" group and a LRINEC score of 8 or greater without CRP value would have placed the patient in the "high risk" group. These patients missing CRP values were added to these respective groups.

RESULTS

Among the 948 ED patients with cellulitis, more than one-tenth (10.7%, n=102 of 948) were moderate or high risk for NF based on LRINEC score. Of the 135 ED patients with a diagnosis of NF, 22 patients had valid CRP laboratory values and LRINEC scores were calculated. Among the other 113 patients without CRP values, six patients had a LRINEC score ≥ 8, and 19 patients had a LRINEC score ≤ 1. Thus, a total of 47 patients were further classified based on LRINEC score without a CRP value. More than half of the NF group (63.8%, n=30 of 47) had a low risk based on LRINEC ≤5. Moreover, LRINEC appeared to perform better in the diabetes population than in the non-diabetes population.

CONCLUSION

The LRINEC score may not be an accurate tool for NF risk stratification and differentiation between cellulitis and NF in the ED setting. This decision instrument demonstrated a high false positive rate when determining NF risk stratification in confirmed cases of cellulitis and a high false negative rate in cases of confirmed NF.

Laboratory risk indicator for necrotising fasciitis (LRINEC) score for the assessment of early necrotising fasciitis: a systematic review of the literature

Introduction Early operative debridement of necrotising fasciitis is a major outcome determinant. Identification and diagnosis of such patients can be clinically difficult. The Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score first published in 2004 is based on routinely performed parameters and offers a method for identifying early cases. No literature review has yet been performed on the application of such a score. Methods A systematic review of English-language literature was performed from 2004 to 2014 to identify articles reporting use of LRINEC score and the incidence of necrotising fasciitis. We performed a critical review of PubMed, Medline and Embase in line with the PRISMA statement. A meta-analysis was performed with a random effects model and 95% confidence interval. Suitable correlation coefficient and receiver operating characteristic (ROC) curves were also calculated. Results After application of inclusion criteria, 16 studies with 846 patients were included. The mean LRINEC score in patients with necrotising fasciitis was 6.06. Two papers reported LRINEC score in patients without necrotising fasciitis with a mean 2.45. All six studies with a reported coefficient of variance were < 1; Pearson correlation coefficient was r = 0.637 (P = 0.011). An ROC curve showed an area under the curve of 0.927. Conclusions The LRINEC score is a useful clinical determinant in the diagnosis and surgical treatment of patients with necrotising fasciitis, with a statistically positive correlation between LRINEC score and a true diagnosis of necrotising fasciitis.

Cadaver-based Necrotizing Fasciitis Model for Medical Training

Necrotizing fasciitis is a devastating infectious disease process that is characterized by extensive soft tissue necrosis along deep fascial planes, systemic toxicity, and high mortality. Ultrasound imaging is a rapid and non-invasive tool that can be used to help make the diagnosis of necrotizing fasciitis by identifying several distinctive sonographic findings. The purpose of this study is to describe the construction of a realistic diagnostic training model for necrotizing fasciitis using fresh frozen cadavers and common, affordable materials.

Presently, fresh non-embalmed cadavers have been used at medical institutions for various educational sessions including cadaver-based ultrasound training sessions. Details for the preparation and construction of a necrotizing fasciitis cadaver model are presented here. This paper shows that the images obtained from the cadaver model closely imitate the ultrasound appearance of fluid and gas seen in actual clinical cases of necrotizing fasciitis.

Therefore, it can be concluded that this cadaver-based model produces high-quality sonographic images that simulate those found in true cases of necrotizing fasciitis and is ideal for demonstrating the sonographic findings of necrotizing fasciitis.

Management and Novel Adjuncts of Necrotizing Soft Tissue Infections

Necrotizing soft tissue infections (NSTI) have been recognized for millennia and continue to impose considerable burden on both patient and society in terms of morbidity, death, and the allocation of resources. With improvements in the delivery of critical care, outcomes have improved, although disease-specific therapies are lacking. The basic principles of early diagnosis, of prompt and broad antimicrobial therapy, and of aggressive debridement have remained unchanged. Clearly novel and new therapeutics are needed to combat this persistently lethal disease. This review emphasizes the pillars of NSTI management and then summarizes the contemporary evidence supporting the incorporation of novel adjuncts to the pharmacologic and operative foundations of managing this disease.

The laboratory risk indicator for necrotizing fasciitis (LRINEC) scoring: the diagnostic and potential prognostic role

BACKGROUND

Necrotizing fasciitis (NF) is a devastating soft tissue infection associated with potentially poor outcomes. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score has been introduced as a diagnostic tool for NF. We aimed to evaluate the prognostic value of LRINEC scoring in NF patients.

METHODS

A retrospective analysis was conducted for patients who were admitted with NF between 2000 and 2013. Based on LRINEC points, patients were classified into (Group 1: LRINEC < 6 and Group 2: LRINEC ≥ 6). The 2 groups were analyzed and compared. Primary outcomes were hospital length of stay, septic shock and hospital death.

RESULTS

A total of 294 NF cases were identified with a mean age 50.9 ± 15 years. When compared to Group1, patients in Group 2 were 5 years older (p = 0.009), more likely to have diabetes mellitus (61 vs 41%, p < 0.001), Pseudomonas aeruginosa infection (p = 0.004), greater Sequential Organ Failure Assessment (SOFA) score (11.5 ± 3 vs 8 ± 2, p = 0.001), and prolonged intensive care (median 7 vs 5 days) and hospital length of stay (22 vs 11 days, p = 0.001). Septic shock (37 vs. 15%, p = 0.001) and mortality (28.8 vs. 15.0%, p = 0.005) were also significantly higher in Group 2 patients. Using Receiver operating curve, cutoff LRINEC point for mortality was 8.5 with area under the curve of 0.64. Pearson correlation analysis showed a significant correlation between LRINEC and SOFA scorings (r = 0.51, p < 0.002).

DISCUSSION

Early diagnosis, simplified risk stratification and on-time management are vital to achieve better outcomes in patients with NF.

CONCLUSIONS

Beside its diagnostic role, LRINEC scoring could predict worse hospital outcomes in patients with NF and simply identify the high-risk patients. However, further prospective studies are needed to support this finding.

Association between cytokine response, the LRINEC score and outcome in patients with necrotising soft tissue infection: a multicentre, prospective study

Early assessment of necrotising soft tissue infection (NSTI) is challenging. Analysis of inflammatory markers could provide important information about disease severity and guide decision making. For this purpose, we investigated the association between cytokine levels and the Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC)-score, disease severity and mortality in NSTI patients. In 159 patients, plasma was analysed for IL-1β, IL-6, IL-10 and TNF-α upon admission. The severity of NSTI was assessed by SAPS, SOFA score, septic shock, microbial aetiology, renal replacement therapy and amputation. We found no significant difference in cytokine levels according to a LRINEC- score above or below 6 (IL-1β: 3.0 vs. 1.3; IL-6: 607 vs. 289; IL-10: 38.4 vs. 38.8; TNF-α: 15.1 vs. 7.8 pg/mL, P > 0.05). Patients with β-haemolytic streptococcal infection had higher level of particularly IL-6. There was no difference in mortality between patients with a LRINEC-score above or below 6. In the adjusted analysis assessing 30-day mortality, the association was strongest for IL-1β (OR 3.86 [95% CI, 1.43-10.40], P = 0.008) and IL-10 (4.80 [1.67-13.78], P = 0.004). In conclusion, we found no significant association between the LRINEC-score and cytokine levels on admission. IL-6 was consistently associated with disease severity, whereas IL-1β had the strongest association with 30-day mortality.

Necrotizing Fasciitis: How Reliable are the Cutaneous Signs?

Necrotizing fasciitis (NF) is a surgical emergency. It is often aggressive and characterized by the rapidly progressive inflammatory infection of the fascia that causes extensive necrosis of the subcutaneous tissue and fascia, relatively sparing the muscle and skin tissue. As the disease progresses, thrombosis of the affected cutaneous perforators subsequently devascularizes the overlying skin. The course indeed can be a fulminant one. The diagnosis of NF, especially in the early stages, is extremely challenging, and it can be very close in presentation to other skin and subcutaneous tissue infections. The primary site of the pathology is the deep fascia. Necrosis of the tissues and fascia may manifest as erythema without sharp margins, swelling, warmth, shiny, and exquisitely tender areas. Pain out of proportion to physical examination findings may be observed. The subcutaneous tissue may be firm and indurated such that the underlying muscle groups cannot be distinctly palpated. Eventually, as the overlying skin is stripped of its blood supply, skin necrosis ensues and hemorrhagic bullae form. Bacteremia and sepsis invariably develop when the infection is well established. This paper discusses some of issues related to the cutaneous signs found in NF and also provides a review the current, available literature on the subject matter.

A comparison of necrotising fasciitis in diabetics and non-diabetics

Aims

Diabetes mellitus is the most common co-morbidity associated with necrotising fasciitis. This study aims to compare the clinical presentation, investigations, Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score, microbiology and outcome of management of this condition in diabetic and non-diabetic patients.

Patients and Methods

The medical records of all patients with surgically proven necrotising fasciitis treated at our institution between 2005 and 2014 were reviewed. Diagnosis of necrotising fasciitis was made on findings of ‘dishwater’ fluid, presence of greyish necrotic deep fascia and lack of bleeding on muscle dissection found intra-operatively. Information on patients’ demographics, presenting symptoms, clinical signs, investigations, treatment and outcome were recorded and analysed.

Results

A total of 127 patients with surgically proven necrotising fasciitis were included in this study. In all, 78 (61.4%) were diabetic and 49 (38.6%) were non-diabetic. Diabetics tended to have polymicrobial infections (p = 0.03), renal impairment (p < 0.001), end-stage renal disease (p = 0.001) and multiple co-morbidities (p < 0.001). They presented atypically, with less tenderness (p = 0.042) and less hypotension (p = 0.034). This resulted in higher rates of misdiagnosis (p = 0.038) and a longer time to surgery (p = 0.05) leading to longer hospital stays (p = 0.043) and higher rates of amputation (p = 0.045). However, the rate of mortality is comparable (p = 0.525). A LRINEC score of > 8 appears to be more sensitive in diabetic patients (p < 0.001). However, the increased sensitivity in diabetic patients may be related to hyperglycemia and electrolyte abnormalities associated with renal impairment in these patients.

Conclusion

The LRINEC score must be used with caution in diagnosing necrotising fasciitis in diabetic patients. A high index of suspicion is key to the early diagnosis and subsequent management of these patients. Cite this article: Bone Joint J 2016;98-B:1563–8.

Necrotising fasciitis of the extremities: implementation of new management technologies

INTRODUCTION

Necrotising fasciitis (NF) is potentially life-threatening soft-tissue infection. Early diagnosis and aggressive surgical debridement are critical to decrease mortality and morbidity. The impacts of new management technologies such as hydro-bisturi-assisted debridement (HAD) and negative pressure wound therapy (NPWT) are not yet clear with respect to treatment of NF. The objective of this study was to describe laboratory (including LRINEC score), clinical and microbiological factors, treatment methods and outcomes related to managing necrotising fasciitis, focusing on the implementation of new treatment methods in our centre.

METHODS

From June 2010 to June 2014, adult patients diagnosed with necrotising fasciitis affecting an upper or lower limb that were admitted to our hospital, a referral tertiary care centre, were eligible to participate in this study. Demographic data, clinical features, location of infection, Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score on the day of admission, microbiology and laboratory results, use of HAD, wound management using NPWT, and patient outcomes were retrospectively analysed. A univariate risk factor analysis was performed, in an attempt to define prognostic factors for mortality.

RESULTS

A total of 20 patients satisfied the inclusion criteria. Type II NF (Group A ß-haemolytic streptococci) was found in 8 cases (40%). The average LRINEC score on the day of admission was 6. The lower extremity was affected in 60% of the cases. All patients were treated operatively, with 2.5 interventions on average. Hydro-bisturi was used in the first debridement in 40% of the cases (8 out 20). In 75% of the studied cases, Negative Pressure Wound Therapy (NPWT) was the technique selected for surgical wound management. The global mortality rate was 30%. On univariate analysis, the only factors significantly associated with mortality were high levels of creatinin (p=0.033) and low blood glucose levels (p=0.012). Finally, four amputations were observed in this series.

CONCLUSION

We confirm that necrotising fasciitis (NF) of the extremities, despite new advancements in treatment and critical care management, is still a potentially life-threatening soft-tissue infection (30% mortality). New, advanced wound management modalities have been heavily used in management of necrotising fasciitis, but these have not had significant impacts on morbidity and mortality rates.