Therapies for necrotising fasciitis

Can The Systemic Immune-Inflammation Index (SII) and Charlson Comorbidity Index (CCI) be used to predict mortality in patients with necrotizing fasciitis?

PURPOSE

This study aimed to determine the impact of mortality and morbidity indices on the diagnosis and prognosis of patients suffering from necrotizing fasciitis.

METHODS

A retrospective analysis was performed on 41 patients (26 females, 15 males) with necrotizing fasciitis (NF). The SII (Systemic Immune-Inflammation Index) was computed using the formula SII = (P × N)/L, where P, N, and L measure the counts of peripheral platelets, neutrophils, and lymphocytes, respectively. This study evaluated the clinicopathological characteristics and follow-up information to assess the comparative effectiveness of SII, CCI (Charlson Comorbidity Index), and LRINEC (Laboratory Risk Indicator for Necrotizing Fasciitis) scores as mortality and morbidity indices for patients with NF.

RESULTS

The optimal cut-off for SII was determined to be 455. The SII value in the group with mortality was significantly higher compared to the group without mortality (p < 0.05). The CCI value in the group with mortality was significantly higher than the group without mortality (p < 0.05). The SII and CCI values were found to be effective in distinguishing between patients who suffered mortality and those who did not.

CONCLUSION

SII is a powerful tool for predicting mortality in patients with necrotizing fasciitis (NF). The SII index provides a novel, easily accessible, and inexpensive indicator for monitoring the progress and predicting the survival of patients with NF.

Under the Skin: A Case Series of Clostridium sordellii Necrotizing Soft Tissue Infections in Patients Who Inject Drugs

Clostridium sordellii has been well-associated as a cause of obstetric infections but is a less commonly recognized organism of necrotizing skin and soft tissue infections (NSTI). C. sordelli infections are rare with only 14 cases reported in the literature to date. These infections are often associated with profound septic shock and the mortality rate remains high. We report four patients who presented with C. sordellii NSTI over a period of two years at an academic medical center. Notably, injection drug use was the main risk factor for infection in these patients. Appropriate management of C. sordellii NSTI necessitates a combination of antibiotics and emergent surgical intervention. However, despite these efforts, the mortality rate remains high, with three of the four patients dying. Clinicians should consider NSTI in the differential diagnosis when evaluating skin and soft tissue infections in people who inject drugs. Furthermore, it is imperative to educate patients who engage in injection drug use on the potential risks associated with NSTI and inform them of warning signs that warrant immediate medical attention. The devastating consequences of C. sordellii-associated NSTI in this vulnerable population can be mitigated by enhancing awareness and facilitating early intervention.

Compartment syndrome as a novel complication of extended spectrum beta lactamase Escherichia coli necrotising soft tissue infection – A case report

Introduction and importance

Necrotising soft tissue infections (NSTI) encompass a group of destructive soft tissue disease processes which can involve skin, subcutaneous tissue, fascia and or muscle, associated with rapid spread along tissue planes and mortality. Clinical presentations include progressive pain, suppuration/necrosis and systemic toxicity with haemodynamic instability. While diagnosis is based on clinical findings it can be augmented with imaging. Treatment is typically in the form of resuscitation, immediate administration of broad spectrum intravenous antibiotics and urgent source control through radical surgical debridement.

Case presentation

An 82-year-old man presented with left forearm/hand pain and fevers in the context of immunocompromise. Examination found tense swelling of the left volar and dorsal forearm and hand, absent distal pulses with pain and paraesthesia over both surfaces. He underwent surgical debridement with fasciotomy and remained in intensive care with blood cultures revealing ESBL E. coli.

Clinical discussion

Compartment syndrome is a rare complication of NSTI and its clinical presentation can obscure early diagnosis. ESBL E. coli is an uncommon pathogen to cause monomicrobial infection and must be accounted for when considering broad spectrum empirical antibiotic cover.

Conclusion

Review of this case and the literature show a rare presentation of NSTI and highlights the importance of early diagnosis based on even a small index of suspicion. It also shows the key significance rationalisation of antibiotics as soon as practicable, given that even broad spectrum empirical cover can be inappropriate in the context of novel microorganisms, particularly in high risk patients.

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First recorded case of monomicrobial ESBL E. coli compartment syndrome

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ESBL E. coli NSTI is rare and not covered by many empirical antimicrobial guidelines.

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Compartment syndrome secondary to NSTI is uncommon and associated with streptococci.

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Early recognition and prompt management are essential to prognosis.

A Systematic Review and Meta-Analysis of the Effectiveness of LRINEC Score for Predicting Upper and Lower Extremity Necrotizing Fasciitis

This review and meta-analysis aims to assess the prognostic value of the Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score for detecting necrotizing fasciitis in the extremities. The LRINEC score has been validated in multiple studies as a clinical tool for differentiating necrotizing fasciitis from non-necrotizing infections however many studies do not specify the location of infection. As the prevalence of diabetes and diabetic foot infections continues to rise, the utility of LRINEC scores in these populations becomes of increased importance. Four databases were reviewed for citations between January 2010 and December 2020. English, full text articles reporting the diagnostic effects of LRINEC were utilized in the systematic review portion of this paper. Further inclusion of 2 × 2 tables and discussion specific to the extremities were applied for citations implemented in the meta-analysis. Of the 111 results, 12 citations (n = 932) were included in this review. The diagnostic sensitivity of the LRINEC score ranged from 36% to 77% while specificity ranged from 72% to 93%. Cumulative odds ratio for LRINEC ≥6 among the 4 studies assessing extremity necrotizing fasciitis was 4.3 with p value of <.05. Sensitivity, specificity, positive predictive value, and negative predictive value was 49.39%, 83.17%, 34.91%, and 89.99%, respectively. Accuracy, the classification by whether a patient was correctly classified, was 77.95%. LRINEC score is effective at distinguishing necrotizing fasciitis from other soft tissue infections however the LRINEC's score greatest clinical application may be its ability to rule out necrotizing fasciitis while its ability to accurately identify the presence of infection remains suboptimal.

First Reported Australian case of Fatal Streptococcal Group B Pneumonia (serotype 21) Necrotising fasciitis complicated by Toxic Shock Like Syndrome – A Case report and review

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Group B Streptococcus Pneumonia Necrotising fasciitis (GBSPn NF) is uncommon.

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Only 5 reported cases have been published between 2011 and 2020.

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GBSPn NF has a high mortality.

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GBSPn NF is associated with Toxic like Shock Syndrome.

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Reliance on severity scoring systems could have a deleterious outcome on patients.

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Clinical suspicion and early debridement remain the mainstay of therapy.

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Empirical antibiotics are essential according to local therapeutic guidelines.

Introduction

NF is a life-threatening infection and progressive disease resulting in widespread fulminant tissue destruction. It is rarely caused by Group B Streptococcus pneumonia. Early management with surgical removal of devitalized tissue and urgent antibiotic administration are key therapies.

Aim

The aim of this report is to highlight the importance of atypical microorganisms seen in NF.

Method

A case presentation and cohort summary of reported NF cases secondary to SPN from the year 2011 to 2020.

Results

We report the case of a 67-year-old male, not on immune-suppressive medications, admitted to our intensive care unit with septic shock and multiorgan failure secondary to left leg NF following a 3-week history of cactus prick with an SPN bacteraemia and LRINEC score of 5 on admission. He required multiple surgical debridements and was commenced on appropriate antibiotics. Despite continuous vasopressor supportive therapy, high flux CRRT, and IVIG, our patient died after an 8-day inpatient stay. A 10-year review showed only 5 reported GBSPn NF cases with an associated mortality rate of 40%.

Conclusion

A high clinical suspicion of SPN infections in NF is required to avoid high mortality with early diagnosis and targeted anti-microbial therapy. Severity scores may not align with clinical severity.

Necrotizing fasciitis caused by the treatment of chronic non-specific back pain

Background

Chronic back pain is a multifactorial disease that occurs particularly in adults and has many negative effects on the quality of daily life. Therapeutic strategies are often multimodal and designed for a long-term therapy period. In some cases, one option is joint infiltration or intrathecal injection with local anaesthetics. An adverse effect of this intervention may be necrotic fasciitis, a disease with high mortality and few therapeutic options.

Case presentation

This case shows a 53-year-old female patient who developed necrotic fasciitis after infiltrations of the sacroiliac joint and after epidural-sacral and intrathecal injections.

Conclusion

Thanks to early and aggressive surgical intervention, antibiotic treatment and hyperbaric oxygenation, she survived this serious complication and was able to return to life.

Medico-legal importance of necrotizing fasciitis

Despite the rarity of necrotizing fasciitis (NF), it is a relatively common cause of death in many lawsuits. Families seek financial compensation or legal charges against those they believe to be involved in the death, usually physicians who did not identify the infection soon enough. This paper explores six cases in forensic pathology practice where NF posed a unique medico-legal dilemma.

Whole-organism phenotypic screening for anti-infectives promoting host health

To date, antibiotics have been identified on the basis of their ability to kill bacteria or inhibit their growth rather than directly for their capacity to improve clinical outcomes of infected patients. Although historically successful, this approach has led to the development of an antibiotic armamentarium that suffers from a number of shortcomings, including the inevitable emergence of resistance and, in certain infections, suboptimal efficacy leading to long treatment durations, infection recurrence, or high mortality and morbidity rates despite apparent bacterial sterilization. Conventional antibiotics fail to address the complexities of in vivo bacterial physiology and virulence, as well as the role of the host underlying the complex, dynamic interactions that cause disease. New interventions are needed, aimed at host outcome rather than microbiological cure. Here we review the role of screening models for cellular and whole-organism infection, including worms, flies, zebrafish, and mice, to identify novel therapeutic strategies and discuss their future implications.

A Red Blood Cell Membrane-Camouflaged Nanoparticle Counteracts Streptolysin O-Mediated Virulence Phenotypes of Invasive Group A Streptococcus

Group A Streptococcus (GAS), an important human-specific Gram-positive bacterial pathogen, is associated with a broad spectrum of disease, ranging from mild superficial infections such as pharyngitis and impetigo, to serious invasive infections including necrotizing fasciitis and streptococcal toxic shock syndrome. The GAS pore-forming streptolysin O (SLO) is a well characterized virulence factor produced by nearly all GAS clinical isolates. High level expression of SLO is epidemiologically linked to intercontinental dissemination of hypervirulent clonotypes and poor clinical outcomes. SLO can trigger macrophage and neutrophil cell death and/or the inactivation of immune cell functions, and promotes tissue injury and bacterial survival in animal models of infection. In the present work, we describe how the pharmacological presentation of red blood cell (RBC) derived biomimetic nanoparticles ("nanosponges") can sequester SLO and block the ability of GAS to damage host cells, thereby preserving innate immune function and increasing bacterial clearance in vitro and in vivo. Nanosponge administration protected human neutrophils, macrophages, and keratinocytes against SLO-mediated cytotoxicity. This therapeutic intervention prevented SLO-induced macrophage apoptosis and increased neutrophil extracellular trap formation, allowing increased GAS killing by the respective phagocytic cell types. In a murine model of GAS necrotizing skin infection, local administration of the biomimetic nanosponges was associated with decreased lesion size and reduced bacterial colony-forming unit recovery. Utilization of a toxin decoy and capture platform that inactivates the secreted SLO before it contacts the host cell membrane, presents a novel virulence factor targeted strategy that could be a powerful adjunctive therapy in severe GAS infections where morbidity and mortality are high despite antibiotic treatment.

Intravenous immunoglobulin in necrotizing fasciitis - A case report and review of recent literature

Introduction

Necrotizing fasciitis (NF) is an inflammatory disease of the soft tissue, which causes local tissue destruction and can lead to lethal septic shock. The therapy consists of early surgical treatment of the septic focus and an accompanying broad spectrum antibiotic therapy. Recent literature considers the additional use of immunoglobulin therapy in severe soft skin and tissue infections.

Presentation of case

In this report, we describe the case of a 33-year-old male patient treated at a university hospital intensive care unit because of an NF of his left leg. The patient rapidly developed a complicated septic disease after a minor superficial trauma. Despite intense microbiological diagnosis, no causative pathogens were identified. After non-responding to established broad anti-infective treatment, the patient received intravenous immunoglobulin, that rapidly improved his clinical condition.

Discussion

NF represents a disease processes, which is characterized by fulminant, widespread necrosis of soft tissue, systemic toxicity, and high mortality (>30%). Beside the surgical debridement and broad spectrum antibiotic therapy IVIg therapy might be an additional option in the treatment of NF. But the current literature supporting the use of IVIG in NF is largely based on retrospective or case-controlled studies, and only small randomized trials.

Conclusion

The demonstrated case suggests that IVIg treatment of patients with NF can be considered in case of hemodynamic unstable, critically ill patients. Although randomized controlled trials are missing, some patients might benefit from diminishing hyperinflammation by immunoglobins.

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Necrotizing fasciitis (NF) is an inflammatory disease, which causes local tissue destruction up to lethal septic shock.

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We describe the case of a 33-year-old male patient representing an NF of his left leg.

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After non-responding to established broad anti-infective treatment, the patient received immunoglobulin (IVIg).

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The presented case suggests that IVIg treatment of patients with NF might be considered in case of critically ill patients.

A Neutralizing Monoclonal IgG1 Antibody of Platelet-Activating Factor Acetylhydrolase SsE Protects Mice against Lethal Subcutaneous Group A Streptococcus Infection

Group A Streptococcus (GAS) can cause life-threatening invasive infections, including necrotizing fasciitis. There are no effective treatments for severe invasive GAS infections. The platelet-activating factor (PAF) acetylhydrolase SsE produced by GAS is required for invasive GAS to evade innate immune responses and to invade soft tissues. This study determined whether the enzymatic activity of SsE is critical for its function in GAS skin invasion and inhibition of neutrophil recruitment and whether SsE is a viable target for immunotherapy for severe invasive GAS infections. An isogenic derivative of M1T1 strain MGAS5005 producing SsE with an S178A substitution (SsE(S178A)), an enzymatically inactive SsE mutant protein, was generated. This strain induced higher levels of neutrophil infiltration and caused smaller lesions than MGAS5005 in subcutaneous infections of mice. This phenotype is similar to that of MGAS5005 sse deletion mutants, indicating that the enzymatic activity of SsE is critical for its function. An anti-SsE IgG1 monoclonal antibody (MAb), 2B11, neutralized the PAF acetylhydrolase activity of SsE. Passive immunization with 2B11 increased neutrophil infiltration, reduced skin invasion, and protected mice against MGAS5005 infection. However, 2B11 did not protect mice when it was administered after MGAS5005 inoculation. MGAS5005 induced vascular effusion at infection sites at early hours after GAS inoculation, suggesting that 2B11 did not always have access to infection sites. Thus, the enzymatic activity of SsE mediates its function, and SsE has the potential to be included in a vaccine but is not a therapeutic target. An effective MAb-based immunotherapy for severe invasive GAS infections may need to target virulence factors that are critical for systemic survival of GAS.

Intravenous immunoglobulin in critically ill adults: When and what is the evidence?

Intravenous immunoglobulin (IVIg) use is growing dramatically internationally due to the increasing numbers of acute and chronic conditions that may benefit from IVIg. Patients with conditions that may benefit from IVIg might require intensive care unit (ICU) admission, supporting the need to review IVIg use in the critical care setting. The most common clinical indications for IVIg in adults that may require ICU admission and are commonly supported under clinical practice guidelines are Guillain-Barré syndrome, myasthenia gravis and Lambert-Eaton myasthenic syndrome, inflammatory myopathies, and primary or secondary immunodeficiency diseases complicated by severe bacterial sepsis. Other emerging indications include necrotizing fasciitis, toxic epidermal necrolysis/Stevens-Johnson syndrome, and toxic shock syndrome. The evidence for IVIg use in sepsis and septic shock remains controversial and insufficient to recommend its routine use. Intravenous immunoglobulin is expensive and also carries risks of adverse effects, including common and benign infusion-related reactions, as well as relatively rare and more serious problems, such as thromboembolic events, renal failure, and aseptic meningitis. In this article, we review the literature on conditions requiring ICU admission and IVIg, and we classify them as supported, emerging, or unsupported indications based on the available evidence and guidelines for clinical use of IVIg.

Disease manifestations and pathogenic mechanisms of Group A Streptococcus

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes mild human infections such as pharyngitis and impetigo and serious infections such as necrotizing fasciitis and streptococcal toxic shock syndrome. Furthermore, repeated GAS infections may trigger autoimmune diseases, including acute poststreptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease. Combined, these diseases account for over half a million deaths per year globally. Genomic and molecular analyses have now characterized a large number of GAS virulence determinants, many of which exhibit overlap and redundancy in the processes of adhesion and colonization, innate immune resistance, and the capacity to facilitate tissue barrier degradation and spread within the human host. This improved understanding of the contribution of individual virulence determinants to the disease process has led to the formulation of models of GAS disease progression, which may lead to better treatment and intervention strategies. While GAS remains sensitive to all penicillins and cephalosporins, rising resistance to other antibiotics used in disease treatment is an increasing worldwide concern. Several GAS vaccine formulations that elicit protective immunity in animal models have shown promise in nonhuman primate and early-stage human trials. The development of a safe and efficacious commercial human vaccine for the prophylaxis of GAS disease remains a high priority.

Disease manifestations and pathogenic mechanisms of Group A Streptococcus

Streptococcus pyogenes, also known as group A Streptococcus (GAS), causes mild human infections such as pharyngitis and impetigo and serious infections such as necrotizing fasciitis and streptococcal toxic shock syndrome. Furthermore, repeated GAS infections may trigger autoimmune diseases, including acute poststreptococcal glomerulonephritis, acute rheumatic fever, and rheumatic heart disease. Combined, these diseases account for over half a million deaths per year globally. Genomic and molecular analyses have now characterized a large number of GAS virulence determinants, many of which exhibit overlap and redundancy in the processes of adhesion and colonization, innate immune resistance, and the capacity to facilitate tissue barrier degradation and spread within the human host. This improved understanding of the contribution of individual virulence determinants to the disease process has led to the formulation of models of GAS disease progression, which may lead to better treatment and intervention strategies. While GAS remains sensitive to all penicillins and cephalosporins, rising resistance to other antibiotics used in disease treatment is an increasing worldwide concern. Several GAS vaccine formulations that elicit protective immunity in animal models have shown promise in nonhuman primate and early-stage human trials. The development of a safe and efficacious commercial human vaccine for the prophylaxis of GAS disease remains a high priority.

Necrotising fasciitis

A patient in his late 50s who suffered from necrotising fasciitis is described in this case report. The patient first presented at the chest pain unit, where he reported of respiratory distress and showed systemic signs of an infection. Because of progressive skin lesions indicative of necrotising fasciitis on both the lower extremities, the patient was immediately rushed into surgery and was treated at the intensive care unit. Despite receiving immediate treatment, the patient died of this rapidly spreading infectious disease. Because of the fast advance of this disease, we would like to emphasise the importance of early recognition of symptoms.

Necrotizing Fasciitis: A Study of 48 Cases

Necrotizing fasciitis represents a group of highly lethal infections characterized by rapidly progressing inflammation and necrosis. The aim of the study was to analyze the clinical profile, microbial flora, and predisposing risk factors in patients with necrotizing fasciitis. Lastly, we aimed to formulate a protocol for management of necrotizing fasciitis. Forty-eight cases of necrotizing fasciitis patients who reported to our hospital between April 2007 and September 2009 were included in the study. The commonest predisposing factors were age greater than 50 years (58 % cases) and diabetes mellitus (52 % cases). The commonest site involved was extremity (70.8 %). Majority of infections were polymicrobial (87.5 %). Repeated aggressive debridement was the commonest surgical procedure performed. Early and aggressive surgical debridement, often in multiple sittings, supplemented by appropriate antibiotics and supportive therapy, forms the key to a successful outcome in necrotizing fasciitis.

The broad landscape of immune interactions with Staphylococcus aureus: from commensalism to lethal infections

Staphylococcus aureus is a gram-positive bacterium that is present in the nostrils of a quarter of the general population without causing any apparent disease. However, S. aureus can also act as a pathogen to cause severe infections. The factors determining the balance between its commensal and pathogenic states are not understood. Emerging evidence suggests that S. aureus, in addition to inducing a pro-inflammatory response, may have the capacity to modulate the host immune system. The latter is in part the result of recognition of specific molecules embedded in the peptidoglycan layer of the staphylococcal cell wall that bind to TLR2 on host antigen-presenting cells and induce a strong IL-10 response that down regulates the adaptive T cell response. This mechanism can partially explain the duality of interactions between S. aureus and the human immune system by favoring nasal colonization instead of staphylococcal diseases. In this review, we discuss the molecular and cellular basis of this mechanism and explore its clinical implications.

Invasive group A streptococcal infection: an update on the epidemiology and orthopaedic management

Invasive group A streptococcus (iGAS) is the most common cause of monomicrobial necrotising fasciitis. Necrotising infections of the extremities may present directly to orthopaedic surgeons or by reference from another admitting specialty. Recent epidemiological data from the Health Protection Agency suggest an increasing incidence of iGAS infection in England. Almost 40% of those affected had no predisposing illnesses or risk factors, and the proportion of children presenting with infections has risen. These observations have prompted the Chief Medical Officer for the Central Alerting System in England to write to general practitioners and hospitals, highlighting the need for clinical vigilance, early diagnosis and rapid initiation of treatment in suspected cases. The purpose of this annotation is to summarise the recent epidemiological trends, describe the presenting features and outline the current investigations and treatment of this rare but life-threatening condition.

Toll-like receptor 2 ligands on the staphylococcal cell wall downregulate superantigen-induced T cell activation and prevent toxic shock syndrome

Staphylococcal superantigens are pyrogenic exotoxins that cause massive T cell activation leading to toxic shock syndrome and death. Despite the strong adaptive immune response induced by these toxins, infections by superantigen-producing staphylococci are very common clinical events. We hypothesized that this may be partly a result of staphylococcal strains having developed strategies that downregulate the T cell response to these toxins. Here we show that the human interleukin-2 response to staphylococcal superantigens is inhibited by the simultaneous presence of bacteria. Such a downregulatory effect is the result of peptidoglycan-embedded molecules binding to Toll-like receptor 2 and inducing interleukin-10 production and apoptosis of antigen-presenting cells. We corroborated these findings in vivo by showing substantial prevention of mortality after simultaneous administration of staphylococcal enterotoxin B with either heat-killed staphylococci or Staphylococcus aureus peptidoglycan in mouse models of superantigen-induced toxic shock syndrome.

Postpartum invasive group A streptococcal disease in the modern era

To describe the clinical features of individuals hospitalized for postpartum invasive group A Streptococcus (GAS) infection, a retrospective, population-based study of hospitalized patients in the state of Florida was conducted. Cases of postpartum invasive GAS infection (occurring within 42 days of delivery) were compared to women with other manifestations of invasive GAS disease with respect to their age at the time of admission. Four cases of postpartum invasive GAS infection were detected in this population, yielding a prevalence of 1.6% (4/257) of postpartum disease in this invasive GAS infection database. Patients presented a median of 4 days (mean of 9 days) after delivery with signs and symptoms of infection. Three cases were complicated by bacteremia and one patient had streptococcal toxic shock syndrome. Each patient received multiple antibiotics and survived. No patients received intravenous immunoglobulin. For comparison, a secondary retrospective investigation of a large hospital discharge dataset obtained from the Florida Agency for Health Care Administration was assessed for patients with puerperal GAS infections. This method yielded an additional three cases, whose clinical and demographic characteristics were summarized. These data highlight that postpartum invasive GAS infection continues to complicate pregnancy, though the frequency has decreased markedly over the past century.

Blunt trauma as a risk factor for group A streptococcal necrotizing fasciitis

PURPOSE

Anecdotal reports suggest that blunt trauma and seemingly innocuous musculoskeletal injuries (e.g., muscle strains) are risk factors for developing necrotizing fasciitis (NF) and myositis caused by group A Streptococcus and other bacteria; however, this hypothesis has not been tested in analytic epidemiologic studies of invasive group A streptococcal (GAS) disease. We conducted two case-control studies to determine whether nonpenetrating trauma is a risk factor for either NF or severe cellulitis caused by GAS.

METHODS

A secondary analysis of patients who were hospitalized throughout Florida for invasive GAS disease during a 4-year period was conducted. Two case series were used. The first series comprised patients who had severe GAS cellulitis. The second were patients who had GAS NF. Case-patients were compared to a single control series composed of patients with invasive GAS disease not including either NF or cellulitis (e.g., primary bacteremia, septic arthritis).

RESULTS

After we adjusted for age, race, and clindamycin usage, GAS NF cases were 5.97 times as likely as controls to have a recent history of blunt trauma (p = 0.04). Patients with severe cellulitis were not more likely than controls to have associated blunt trauma.

CONCLUSIONS

Nonpenetrating trauma is significantly associated with the development of GAS NF.

Correlates of length of stay, cost of care, and mortality among patients hospitalized for necrotizing fasciitis

Several previous studies of necrotizing fasciitis (NF) have been single-institution investigations suffering from small samples sizes. This study of 216 NF patients hospitalized in Florida, USA, during 2001 was designed to identify risk factors for length of stay (LOS), total patient charges (TC), and mortality, using a statewide database. Robust gamma mixed regression was used to determine the predictors of LOS and TC while simultaneously accounting for outliers and the clustering of patients in 87 hospitals. Relative risks (RR) for hospital mortality were calculated using binomial regression. The NF hospitalization rate in Florida was 1.3/100,000. The median TC was US$54,533 and cumulative charges for all 216 patients were nearly US$20 million. Patients aged > or =44 years at the time of admission were five times as likely to expire in the hospital than patients who were aged < or =43 years (adjusted RR 5.08, P=0.03). Unexpectedly, diabetes was associated with a 61% reduction in the risk of hospital mortality (adjusted RR 0.39, P=0.04). Age > or =44 years was the most powerful predictor of prolonged LOS, elevated TC, and an increased risk of hospital mortality in patients suffering from NF.