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.

In patients presenting to the emergency department with skin and soft tissue infections what is the diagnostic accuracy of point-of-care ultrasonography for the diagnosis of abscess compared to the current standard of care? A systematic review and meta-analysis

OBJECTIVES

The primary objective of this systematic review was to determine the accuracy of point-of-care ultrasonography (POCUS) in diagnosing abscess in emergency department (ED) patients with skin and soft tissue infections (SSTI). The secondary objective was the accuracy of POCUS in the paediatric population subgroup.

SETTING

Prospective studies set in emergency departments.

PARTICIPANTS

Emergency department patients (adult and paediatric) presenting with SSTI and suspected abscess.

PRIMARY AND SECONDARY OUTCOME MEASURES

This systematic review was conducted according to Cochrane Handbook guidelines, and the following databases were searched: PubMed, MEDLINE, EMBASE and the Cochrane database of systematic reviews (1946-2015). We included prospective cohort and case-control studies investigating ED patients with SSTI and abscess or cellulitis, a defined POCUS protocol, a clearly defined gold standard for abscess and a contingency table describing sensitivity and specificity. Two reviewers independently ascertained all potentially relevant citations for methodologic quality according to QUADAS-2 criteria. The primary outcome measure was the sensitivity and specificity of POCUS for abscess. A preplanned subgroup (secondary) analysis examined the effects in paediatric populations, and changes in management were explored post hoc.

RESULTS

Of 3028 articles, 8 were identified meeting inclusion criteria; all were rated as good to excellent according to QUADAS-2 criteria. Combined test characteristics of POCUS on the ED diagnosis of abscess for patients with SSTI were as follows: sensitivity 96.2% (95% CI 91.1% to 98.4%), specificity 82.9% (95% CI 60.4% to 93.9%), positive likelihood ratio 5.63 (95% CI 2.2 to 14.6) and negative likelihood ratio 0.05 (95% CI 0.01 to 0.11).

CONCLUSIONS

A total of 8 studies of good-to-excellent quality were included in this review. The use of POCUS helps differentiate abscess from cellulitis in ED patients with SSTI.

TRIAL REGISTRATION NUMBER

CRD42015017115.

[COMPARATIVE ESTIMATION OF THE APPLICATION EFFICACY FOR THE COMPOSITION, BASING ON NANODISPERSE SILICA, OWING ANTIMICROBIAL PROPERTIES FOR LOCAL TREATMENT OF PURULENT-INFLAMMATORY PROCESSES]

Comparative estimation of the local treatment results for purulent-inflammatory diseases of soft tissues, using standard methods and composition, owing sorption and antimicrobial properties and basing on a nanodispersedsilica, was conducted. The composition application in complex of treatment have promoted more rapid clearance from necrotized tissues and microorganisms, rapid appearance of granulations, the intoxication severity reduction, the phase I of the wound process duration shortening, what have permitted to put secondary sutures on the wound on the 6 – 7th postoperative day, and total duration of the patients’ stationary treatment have reduced by 3.7 days.

[IMPACT OF THE TISSUES OEDEMA ON THE RESULT OF SURGICAL TREATMENT OF INFLAMMATION]

Significance of the tissues oedema and its elimination in the course of inflammation and the wound healing was investigated. There were analyzed the results of treatment of 68 patients, suffering inflammatory and necrotic affection of soft tissues, including 65 – a lower one, 3 – an upper. In 47 observations the affection course was an acute, while in 18 – chronic. In 36 patients (control group) a local and systemic antibacterial therapy were conducted, and in accordance to indications – surgical interventions; in 32 (main group) this treatment was added with tight bandaging of the extremity, using elastic bandage. Tight squeezing of tissues with the oedema elimination on background of an adequate antibacterial therapy and surgical sanation of purulent-necrotic focus is accompanied by arrest of infiltrative and exudative stages of an acute inflammation, promotes an active course of the inflammation proliferative stage. While treatment of chronic cutaneous defect, the application of tight squeezing have promoted the granulating shaft resolution, the granulation growth in the wound and its boundary epithelization.

[APPLICATION OF VACUUM-THERAPY ON STAGES OF SURGICAL TREATMENT OF THE DIABETIC FOOT SYNDROME]

Vacuum therapy of an acute and chronic wounds was used in a complex of surgical treatment of 228 patients, suffering diabetic foot syndrome. There was established a positive local and systemic action of this method for the treatment of the wound defect. Vacuum therapy of the wounds guarantees the wound process clinical course stabilization, improvement of microcirculation, reduction of their microbial soiling, stimulation of regenerative processes, elimination of endogenous intoxication.

Unusual sites of hydatid cysts in India

Hydatid disease usually affects liver and lungs, but may affect any organ, posing a diagnostic and therapeutic dilemma. We analysed 110 patients with hydatid cyst over 21 years in our general surgical unit, which included 24 cases in unusual sites. The spleen was the most common, followed by skin and soft tissues.

[DYNAMICS OF BACTERIOLOGICAL AND PLANIMETRIC INDICES OF THE WOUND UNDER THE ACTION OF THE SILVER NANOPARTICLES, STABILIZED BY MEXIDOL AND POLYVINYLPYRROLIDONE]

Changes in bacteriological indices through the square of the wound of chemical origin under local impact of the silver nanoparticles (NP), stabilized by 2-ethyl-6-methyl-3-hydroxypyridine succinate (mexidol) and polyvinylpyrrolidone were studied. The wounds of submandibular region were simulated in white rats, using injection of 10% solution of calcium chloride with further opening of necrotic foci and open management of the wound. Beginning from the fifth day, every day the wound was irrigated with liquid, which have contented the stabilized NP of the silver, 0.05% water solution of chlorhexidine or isotonic solution of the the sodium chloride (control). There was established, that the silver NP impact antiseptically and regenerative while the wound treatment, and reduce during 10 days microbial contamination of exudate in 24 times, the wound square--in three times in comparison with original indices. These changes were identical to those while application of chlorhexidine.

Type I Interferon Signaling Prevents IL-1β-Driven Lethal Systemic Hyperinflammation during Invasive Bacterial Infection of Soft Tissue

Type I interferons (IFN-Is) are fundamental for antiviral immunity, but their role in bacterial infections is contradictory and incompletely described. Streptococcus pyogenes activates IFN-I production in innate immune cells, and IFN-I receptor 1 (Ifnar1)-deficient mice are highly susceptible to S. pyogenes infection. Here we report that IFN-I signaling protects the host against invasive S. pyogenes infection by restricting inflammation-driven damage in distant tissues. Lethality following infection in Ifnar1-deficient mice is caused by systemically exacerbated levels of the proinflammatory cytokine IL-1β. Critical cellular effectors of IFN-I in vivo are LysM+ and CD11c+ myeloid cells, which exhibit suppression of Il1b transcription upon Ifnar1 engagement. These cells are also the major source of IFN-β, which is significantly induced by S. pyogenes 23S rRNA in an Irf5-dependent manner. Our study establishes IL-1β and IFN-I levels as key homeostatic variables of protective, yet tuned, immune responses against severe invasive bacterial infection.

[The pitfalls of necrotising soft tissue infection: a 'wake-up call' for surgeons]

Necrotising soft tissue infections require early consultation of an experienced surgeon, regardless of what time of day they occur. Delays in diagnosis and treatment should not occur. Necrotectomy should be skin-sparing when possible. A low threshold for consultation with a tertiary referral center is recommended.

Pitfalls in diagnosing diabetic foot infections

Although the diagnosis of a diabetic foot infection is made based on clinical symptoms and signs, we also use blood laboratory, microbiological and radiological studies to make treatment decisions. All of these diagnostic studies have pitfalls that can lead to a delay in diagnosis. Such delays will likely lead to further tissue damage and to a higher chance of amputation. One of these pitfalls is that some clinicians rely on microbiological, rather than clinical data, to diagnose infection. Though subjective by nature, clinical signs predict outcome of foot infections accurately. Another pitfall is that microbiological data can be misleading. All wounds harbour microorganisms; therefore, a positive wound culture does not mean that a wound is infected. Furthermore, the outcome of cultures of wound swabs does not correlate well with culture results of tissue biopsies. Therapy guidance by wound swab will likely lead to overtreatment of non-pathogenic organisms. Genotyping might have a role in identifying previously unrecognized (combinations of) pathogens in diabetic foot infection, bacteria in sessile phenotype and non-culturable pathogens, e.g. in cases where antibiotics have already been administered. One more pitfall is that the diagnosis of osteomyelitis remains difficult. Although the result of percutaneous bone biopsy is the reference standard for osteomyelitis, some other diagnostic modalities can aid in the diagnosis. A combination of several of these diagnostic tests is probably a good strategy to achieve a higher diagnostic accuracy. Relying on a single test will likely lead to misidentification of patients with osteomyelitis with associated overtreatment and undertreatment.

[PROGNOSIS OF INFECTIVE COMPLICATIONS OF THE GUN-SHOT WOUNDS OF SOFT TISSUES]

The method of prognostication of infectious complications in a gun-shot wound was elaborated, using the methods of logistic regression analysis.

Development of a Novel Model for the Assessment of Dead-Space Management in Soft Tissue

Following extensive surgical debridement in the treatment of infection, a “dead space” can result following surgical closure that can fill with hematoma, an environment conducive to bacterial growth. The eradication of dead space is essential in order to prevent recurrent infection. This study describes a novel small animal model to investigate dead-space management in muscle tissue. Two absorbable test materials were implanted in each animal; beads of calcium sulfate alone, and beads loaded with vancomycin and tobramycin. In-life blood samples and radiographs were taken from each animal following implantation. Animals were sacrificed at 1, 7, 21, 42, and 63 days post-operatively (n = 4), and implant sites were analysed by micro-computed tomography, histology and immunohistochemistry. Complete resorption was confirmed radiographically at 3 weeks post-implantation. Histologically, the host tissue response to both materials was identical, and subsequent healing at the implant sites was observed with no dead space remaining. Vancomycin was not detected in blood serum. However, peak tobramycin levels were detected in all animals at 6 hours post-implantation with no detectable levels in any animals at 72 hours post implantation. Serological inflammatory cytokine expression for IL-6, TNF-α and IL-1β indicated no unusual inflammatory response to the implanted materials or surgical procedure. The model was found to be convenient and effective for the assessment of implant materials for management of dead space in muscle tissue. The two materials tested were effective in resolving the surgically created dead space, and did not elicit any unexpected adverse host response.

Subcutaneous Injection of Percocet: A Case of Severe Soft Tissue Loss

Prescription drug abuse ranks as the second most common class of illicit drug use in the United States, and one mechanism of opiate abuse involves intravenous injection of enteral narcotics such as oxycodone or hydrocodone. The authors describe a patient who sustained significant soft tissue necrosis after intravenously injecting a solution made from crushed enteral narcotics, with a focus on the operative course that resulted due to a delay in initial definitive treatment. The patient's wounds encompassed 8% total body surface area and covered 247 cm2. A 55-year-old female was admitted to the burn unit (West Penn Burn Center, Western Pennsylvania Hospital, Pittsburgh, PA) after she initially presented with infection and cellulitis to her bilateral upper extremities 3 weeks after intravenously injecting herself with crushed oxycodone/acetaminophen. She underwent numerous sequential operative repairs including initial debridement, placement of dermal replacement templates, and several split-thickness autografts and xenografts. Her total length of stay was 59 days, broken into an initial 47-day stay, and a subsequent 12-day readmission due to graft failure secondary to poor follow-up. As the number of prescription drug abusers rises, it is possible that an increase in attempts to intravenously abuse enteral narcotics may also rise. As such, burn centers should be prepared for the extent of potential limb necrosis and the operative treatment that may ensue.

Targeting Staphylococcus aureus α-toxin as a novel approach to reduce severity of recurrent skin and soft-tissue infections

Staphyococcus aureus frequently causes recurrent skin and soft-tissue infection (SSTI). In the pediatric population, elevated serum antibody targeting S. aureus α-toxin is correlated with a reduced incidence of recurrent SSTI. Using a novel model of recurrent SSTI, we demonstrated that expression of α-toxin during primary infection increases the severity of recurrent disease. Antagonism of α-toxin by either a dominant-negative toxin mutant or a small molecule inhibitor of the toxin receptor ADAM10 during primary infection reduces reinfection abscess severity. Early neutralization of α-toxin activity during S. aureus SSTI therefore offers a new therapeutic strategy to mitigate primary and recurrent disease.

A novel mouse model of soft-tissue infection using bioluminescence imaging allows noninvasive, real-time monitoring of bacterial growth

Musculoskeletal infections, including surgical-site and implant-associated infections, often cause progressive inflammation and destroy areas of the soft tissue. Treating infections, especially those caused by multi-antibiotic resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) remains a challenge. Although there are a few animal models that enable the quantitative evaluation of infection in soft tissues, these models are not always reproducible or sustainable. Here, we successfully established a real-time, in vivo, quantitative mouse model of soft-tissue infection in the superficial gluteus muscle (SGM) using bioluminescence imaging. A bioluminescent strain of MRSA was inoculated into the SGM of BALB/c adult male mice, followed by sequential measurement of bacterial photon intensity and serological and histological analyses of the mice. The mean photon intensity in the mice peaked immediately after inoculation and remained stable until day 28. The serum levels of interleukin-6, interleukin-1 and C-reactive protein at 12 hours after inoculation were significantly higher than those prior to inoculation, and the C-reactive protein remained significantly elevated until day 21. Histological analyses showed marked neutrophil infiltration and abscesses containing necrotic and fibrous tissues in the SGM. With this SGM mouse model, we successfully visualized and quantified stable bacterial growth over an extended period of time with bioluminescence imaging, which allowed us to monitor the process of infection without euthanizing the experimental animals. This model is applicable to in vivo evaluations of the long-term efficacy of novel antibiotics or antibacterial implants.

[Frequency of diseases caused by group A streptococci among invasive infections of soft tissues and characteristics of the causative agent]

AIM

Determine frequency of diseases caused by group A streptococci (GAS) among invasive infections of soft tissues; identify emm-types of the isolated streptococci, determine the presence of bacteriophage integrases and toxin genes in their genomes.

MATERIALS AND METHODS

4750 case histories of patients with soft tissue infections of the purulent-surgical department of the 23rd City Clinical Hospital.of Moscow "Medsantrud" in 2008 - 2011 were analyzed. 46 strains of GAS isolated from patients with invasive streptococcus infection (ISI) were studied. GAS identification was carried out by latex-agglutination method. GAS emm-type was determined by molecular-genetic methods, as well as the presence of bacteriophage integrases int2, int3, int4, int5, int6, int7, int49, bacteriophage toxins speA, speI, sla, speC/J, speL, speH, speC, ssa and speB gene present on the chromosomal DNA.

RESULTS

132 cases (2.8%) were attributed to invasive infections. In 46 cases of invasive infections (35%) GAS were isolated. 22 different emm-types of invasive GAS strains were detected. Only speB gene among all the toxin genes (as well as the expression of the gene--SpeB toxin) was detected in all the strains, whereas sla and speI genes were not detected in any of the strains. Genes of the other toxins (ssa, speL, speC, speA, speH, speC/J) occurred in a number of strains. Genes of phage integrases were detected among all the strains however in varying combinations (from 1 to 4 genes).

CONCLUSION

Invasive infections caused by GAS are more frequently spread than had been previously assumed and a high degree of genetic heterogeneity of invasive GAS strains was detected.

[Expedience of application of a dietic therapy in treatment of purulent-septic diseases of soft tissues]

The results of investigation of the dietotherapy impact on the course of purulent-septic process in soft tissues were analyzed. There were operated 58 patients, to 38 of them a certain diet was prescribed. Immediate impact of the diet therapy on the wound process course was established, what was demonstrated by reduction of duration of the earning capacity loss in patients, who have followed a special diet, by 2.58 days.

Vacuum-assisted therapy accelerates wound healing in necrotizing soft tissue infections: our experience in two intravenous drug abuse patients

Negative pressure wound therapy using vacuum-assisted closure (VAC) devices is currently a well established technique for managing complicated wounds. Such wounds occur after aggressive surgical debridement for necrotizing soft tissue infections (NSTI). In this report we present our experience in two intravenous drug abusers managed with VAC for NSTIs. The patients were 25 and 34 years old, HCV positive and presented with oedema of the upper femoral compartments and concomitant severe sepsis. Ultrasonography and computed tomography revealed severe cellulitis, fluid collection and necrosis of the affected fasciae and muscles. After emergent and subsequent aggressive surgical debridement during the first 48h, the VAC device was applied. Both patients had an uncomplicated postoperative course and a fast recovery from their multiorgan dysfunction. Suture closure of the wounds was achieved at the 25th and 38th postoperative days respectively and patients were discharged without any motor deficit. Negative pressure wound therapy is a modern therapeutic modality for treating complicated infected wounds. Moreover, it accelerates wound healing and primary closure, facilitating patient ambulation and recovery. A dedicated medical and nursing team is an important prerequisite for a successful outcome.

Acute focal bacterial nephritis due to methicillin-resistant Staphylococcus aureus in an immunocompetent adult

Acute focal bacterial nephritis (AFBN) is a rare, acute focal infection of the renal parenchyma without liquefaction. The pathogenesis is thought to be due to hematogenous infection or ascending infection from the lower urinary tract. Escherichia coli has been the major pathogen isolated in prior cases, but other Gram-negative enteric pathogens and Staphylococcus aureus have been reported as well. It is well described in children and adults with diabetes and organ transplantation, but has not been previously reported in healthy adults. We report a case of an immunocompetent adult female who presented with a methicillin-resistant Staphylococcus aureus bacteremia after a skin and soft tissue infection that resulted in AFBN.

Timing of redébridement after initial source control impacts survival in necrotizing soft tissue infection

Necrotizing soft tissue infections (NSTIs) are associated with a high mortality rate. There is a lack of literature examining outcomes in NSTI when surgical redébridements are performed in early versus delayed intervals. We hypothesized that early redébridement is associated with improved survival. Patients with NSTIs were prospectively enrolled between January 2006 and December 2011. Patient demographics, comorbidities, primary infection site, laboratory values, tissue cultures, time to surgery, and time between subsequent débridements were obtained. Two study groups with divergent redébridement protocols were observed: a short interval redébridement (SIRD) and an extended interval redébridement (EIRD). Univariate and multivariate statistics were performed. The primary outcome evaluated was in-hospital mortality. Sixty-four patients (46 SIRD, 18 EIRD) were included in the analysis. The two groups had comparable demographics. Polymicrobial NSTI was noted in 61 per cent of patients with Staphylococcus species being the predominant causative organism (59%). Multivariate analysis showed the EIRD protocol to be associated with a significantly increased incidence of acute kidney injury (adjusted odds ratio, 4.9 [1.1 to 22.5]; P = 0.04) and worse overall survival (hazard ratio, 10.6 [2.1 to 53.9]; P = 0.004). Delayed redébridement after initial source control in NSTIs results in worse survival and an increased incidence of acute kidney injury. Further studies to identify the optimal time interval for redébridement are warranted.

Necrotizing soft tissue infections (NSTIs): literary review and description of a Fournier syndrome case

A 62 y.o. male with tight fimosis, swelling, redness, pain on palpating and necrosis of the penis and scrotum was admitted in our clinic, (FGSI = 6) with periferic vasculopathy; and diabetes mellitus type II and he was in dialysis treatment before the hospitalization. The patient was HCV affected. In 24 hours he underwent radical surgical debridement with excision of all necrotic material from penis and scrotum up to the subdermal layer and tissue of doubtful viability for about 75% of the skin and circumcision. In third, fifth and seventh postoperative days he underwent to local infusion of autologous PLT growth factors. The patient was discharged in 9th postoperative day and FGSI was still 6; the skin and subdermal tissue was barely reskined, with low homogeneous granulation, edema was heavely reduced. In our case, deviation from homeostasis status at admission was the main worrying factor. We found that diabetes mellitus and renal dysfunction at admission was also important risk factor for FG. "E.Coli" was the most common organism isolated from patient wound cultures. The FGSI is an objective and easy to apply score method to quantify the metabolic status and can be used to evaluate therapeutic options and assess results.

[Treatment of patients with purulent wounds by using the original method of hydrodynamical drainage]

In this article the work of the Omsk State Medical Academy's department of general surgery is presented. The aim of study was to treat patients with purulent and necrotic wounds of soft tissue by using novel hydrodynamical drainaige. In this research 92 patients were taken part, who were inpatient treatment in the department of purulent surgery City Clinical Hospital No 1 named Kabanov A. N. 2010-2013 with purulent and necrotic wounds of soft tissue. Clinical, laboratory, cytological, bacteriological monitoring were conducted over the of wound process during the treatment. Assessment of the reliability of differences between the mean value of clinical indicators was with the calculation of the criterion t--Student, the method chi2 and Criterion Mann-Whitney U. The proposed method of treatment of purulent wound promotes fast the removal of necrotic tissue and pus in the first phase of the wound process that led to more rapid relief of symptoms of intoxication (fever, leukocytosis and common symptoms) at the patients of the basic group. Due to faster removal of necrotic tissue, reduction of common symptoms of intoxication at the patients of the basic group the transition from degenerative and inflammatory type of cystograms to regenerative occurred one or two days before than in the comparison group.

Magnetic resonance imaging of soft tissue infection with iron oxide labeled granulocytes in a rat model

OBJECT

We sought to detect an acute soft tissue infection in rats by magnetic resonance imaging (MRI) using granulocytes, previously labeled with superparamagnetic particles of iron oxide (SPIO).

MATERIALS AND METHODS

Parasternal infection was induced by subcutaneous inoculation of Staphylococcus aureus suspension in rats. Granulocytes isolated from isogenic donor rats were labeled with SPIO. Infected rats were imaged by MRI before, 6 and 12 hours after intravenous injection of SPIO-labeled or unlabeled granulocytes. MR findings were correlated with histological analysis by Prussian blue staining and with re-isolated SPIO-labeled granulocytes from the infectious area by magnetic cell separation.

RESULTS

Susceptibility effects were present in infected sites on post-contrast T2*-weighted MR images in all animals of the experimental group. Regions of decreased signal intensity (SI) in MRI were detected at 6 hours after granulocyte administration and were more pronounced at 12 hours. SPIO-labeled granulocytes were identified by Prussian blue staining in the infected tissue and could be successfully re-isolated from the infected area by magnetic cell separation.

CONCLUSION

The application of SPIO-labeled granulocytes in MRI offers new perspectives in diagnostic specificity and sensitifity to detect early infectious processes.