Burn septicaemia: an analysis of 79 patients

EVALUATING SEPSIS CRITERIA IN DETECTING ALTERATIONS IN CLINICAL, METABOLIC, AND INFLAMMATORY PARAMETERS IN BURN PATIENTS

ABSTRACT

Sepsis has become the leading cause of death in burn patients. Furthermore, sepsis and septic complications result in significant morbidities and longer hospitalization, which has profound impacts on the healthcare system. Despite this, sepsis in burn patients is surprisingly poorly understood and characterized. This retrospective, single-institution cohort study aimed to increase our understanding of the septic response after burns. We hypothesized that different sepsis definitions will results in distinctive septic trajectories and biochemical patterns after injury. Sepsis was defined by our burn center-specific prospective definition, the American Burn Association criteria, Sepsis-3 criteria, and the Mann-Salinas criteria. Applying these definitions, we compared clinical, metabolic, and inflammatory markers in septic and nonseptic burn patients. We found that the Sepsis-3 criteria are the most reliable screening tool used before clinical diagnoses for detecting sepsis trajectories and biochemical patterns. Moreover, we characterized distinct temporal alterations in biomarkers during the pre- and post-septic periods in burn patients, which may be incorporated into future sepsis definitions to improve the accuracy of a sepsis diagnosis in burn patients.

Epidemiology and etiology of blood stream infections in a Belgian burn wound center

BACKGROUND

Infections are a major cause of morbidity in burn patients. We aimed to investigate the epidemiology and antibiotic susceptibility of blood stream infections in order to gain a better understanding of their role and burden in our Burn Wound Center.

METHODS

This retrospective epidemiological investigation analyzed data derived from medical files of patients admitted to our Burn Wound Center having had at least one positive blood culture between 1 January and 31 December 2018. We focused on the prevalence of causative agents in blood stream infections in function of the time after injury and on their drug sensitivity.

RESULTS

Among the 363 patients admitted to our Burn Wound Center during the study period, 29 had at least one episode of blood stream infection. Gram-negative organisms accounted for 56,36% of the pathogens in blood stream infections, Gram-positives for 38,17%, and yeasts for 5,45%. Pseudomonas aeruginosa was the most common bacterium (20%), followed by Staphylococcus epidermidis (16.36%), Escherichia coli and Klebsiella pneumoniae (9,09% each). A third of the Gram-negative isolates were multidrug resistant. Gram-positive cocci were isolated from blood cultures at a median of 9 days after the injury, earlier than Gram-negative rods (median 15 days). The main sources of blood stream infections were the burn wounds, followed by infected catheters.

CONCLUSIONS

Multidrug resistant bacteria must be considered when selecting empirical antibiotic therapy in septic burn patients. In our center, we need to update our antibiotic guidelines, to review the hospital infection control measures and to introduce routine typing technology.

Pixel Grafting: A Novel Skin Graft Expansion Technique

Skin grafting is the transplantation of skin, a routinely performed procedure to cover the loss of skin. Skin is the largest organ of the body, which falls short of availability in extensive injuries, especially burns. In such a situation, pixel grafting, a novel expansion technique helps to cover a large area with less skin harvest. The objective of the study was to test fast, minimally invasive, easy to use minced split-thickness skin graft to cover large wounds and to reflect on the advantages of pixel graft. It is a pilot study of patients admitted with severe burns. We conclude that with this technique of pixel or minced grafting, large areas can be grafted with minimal donor-site requirement, and the techniques of preparation provide adequate size graft for pixel grafting.

Cost-drivers of medical expenses in burn care management

BACKGROUND

Profound differences exist in the cost of burn care globally, thus we aim to investigate the affected factors and to delineate a strategy to improve the cost-effectiveness of burn management.

METHODS

A retrospective analysis of 66 patients suffering from acute burns was conducted from 2013 to 2015. The average age was 26.7 years old and TBSA was 42.1% (±25.9%). We compared the relationship between cost and clinical characteristics.

RESULTS

The estimated cost of acute burn care with the following formula (10,000 TWD) = -19.80 + (2.67 × percentage of TBSA) + (124.29 × status of inhalation injury) + (147.63 × status of bacteremia) + (130.32 × status of respiratory tract infection).

CONCLUSION

The majority of the cost were associated with the use of antibiotics and burns care. Consequently, it is crucial to prevent nosocomial infection in order to promote healthcare quality and reduce in-hospital costs.

Microbiology in burns patients with blood stream infections: trends over time and during the course of hospitalization

BACKGROUND

Bloodstream infections (BSI) are a major cause of mortality in burns patients. Knowledge of the microbiology is crucial to direct empirical therapy. We sought to determine the causative microorganisms and antibiotic resistance in burns patients with BSI.

METHODS

All consecutive BSI episodes in a tertiary hospital burns unit from 2000 to 2014 were included. The following three subperiods were compared: 2000-2004, 2005-2009 and 2010-2014. Changes in BSI occurring during early and late hospitalization periods were evaluated.

RESULTS

A total of 103 BSI episodes were included. The cumulative incidence was 2.4 episodes/1000 patient days. A positive trend in the frequency of Gram-negative BSI, especially in the upsurge of Pseudomonas aeruginosa and Klebsiella spp. BSI after 2004, was observed. The most common causative pathogens in early BSI were Gram-positive microorganisms. P. aeruginosa and Klebsiella spp. became the predominant aetiology in the fourth week of hospitalization and beyond. There was a progressive increase in imipenem-resistant P. aeruginosa over time (0%, 67%, 75% in 2000-2004, 2005-2009, 2010-2014, respectively) and during the hospital stay (50% vs. 85.7%, in <7 days-BSI vs. >30 days-BSI, respectively). A higher SOFA (Sepsis-related Organ Failure Assessment) score was associated with Gram-negative BSI versus non-Gram-negative BSI (median: 2.5 vs. 0; p = 0.041).

CONCLUSIONS

There is a changing trend in the types of pathogens causing BSI in burns patients over the 14-year period and during the course of hospitalization. The problematic increase in carbapenem-resistance highlights the need for new antimicrobial stewardship policies and antibiotic prescribing protocols.

Use of Implementation Science for a Sustained Reduction of Central-Line-Associated Bloodstream Infections in a High-Volume, Regional Burn Unit

OBJECTIVE We describe the use of implementation science at the unit level and organizational level to guide an intervention to reduce central-line-associated bloodstream infections (CLABSIs) in a high-volume, regional, burn intensive care unit (BICU). DESIGN A single center observational quasi-experimental study. SETTING A regional BICU in Maryland serving 300-400 burn patients annually. INTERVENTIONS In 2011, an organizational-level and unit-level intervention was implemented to reduce the rates of CLABSI in a high-risk patient population in the BICU. At the organization level, leaders declared a goal of zero infections, created an infrastructure to support improvement efforts by creating a coordinating team, and engaged bedside staff. Performance data were transparently shared. At the unit level, the Comprehensive Unit-based Safety Program (CUSP)/ Translating Research Into Practice (TRIP) model was used. A series of interventions were implemented: development of new blood culture procurement criteria, implementation of chlorhexidine bathing and chlorhexidine dressings, use of alcohol impregnated caps, routine performance of root-cause analysis with executive engagement, and routine central venous catheter changes. RESULTS The use of an implementation science framework to guide multiple interventions resulted in the reduction of CLABSI rates from 15.5 per 1,000 central-line days to zero with a sustained rate of zero CLABSIs over 3 years (rate difference, 15.5; 95% confidence interval, 8.54-22.48). CONCLUSIONS CLABSIs in high-risk units may be preventable with the a use a structured organizational and unit-level paradigm. Infect Control Hosp Epidemiol 2017;38:1306-1311.

The MEEK technique: 10-year experience at a tertiary burn centre

Extensive full-thickness burns pose a great challenge to the burn surgeon. Lack of autograft donor sites is an important limiting factor to achieving wound closure. To overcome this problem, various methods of treatment have been suggested in the past, including the MEEK technique. This study was carried out at the Bogenhausen Hospital Burn Unit, Munich, Germany from 2006 to 2015. There were a total of 148 skin grafting operations. The modified MEEK technique was performed on 67 patients. Patients included 34 males and 33 females, with an average age of 39·6 years. The mean percentage body surface burned was 65%, and full-thickness injury occurred in 52%. The mean area graft per procedure was 20%. The viability of the graft as assessed between the 7th and 10th day was generally in the range of 60-90%. The average number of operations required was 2·21. The mean length of stay was 27 days. Infection was documented in five patients, and seven deaths occurred. The mean follow-up was 3·2 years. When faced with large surface area burns and limited donor sites, the MEEK technique is a satisfactory method for coverage.

What should be the antibiotic prescription protocol for burn patients admitted in the department of burns, plastic and reconstructive surgery

This is a prospective study with the aim to determine specific patterns of burn wound bacterial colonisation and antimicrobial resistance profiles. There is a high incidence of infections and septicaemia in post-burn patients, which, in turn, are associated with high morbidity and mortality, a fact that compelled us to undertake this study. The study was conducted over a period 11 months, from 1 August 2014 to 30 June 2015, in 50 burn patients admitted in our burn unit. Wound cultures were taken after 72 hours of admission from all the patients, and then, empirical systemic antibiotics were administered. For wound cultures; 1 cubic cm tissue was taken and placed in aerobic and anaerobic culture vials and transported to the microbiology lab under all aseptic precautions as soon as possible. At the time of fever any time after 72 hours of admission, 16 ml of blood was drawn under all aseptic precautions. Both aerobic and anaerobic blood culture vials were filled with 8 ml of blood each and transported to the microbiology lab. The results of culture and sensitivity reports of 50 patients were recorded. The data obtained was analysed using appropriate statistical analytical tests. The most common organism responsible for bacteraemia is Pseudomonas (43%). Most of the strains of organisms isolated were resistant to commonly used antibiotics in the hospital; Pseudomonas was found 100% resistant to a combination of ampicillin + sulbactum, ceftriaxone and was most often sensitive to imipenem, amikacin and vancomycin. Methicillin-resistant Staphylococcus aureus (MRSA) was also found resistant to commonly used antibiotics like ceftriaxone, ampicillin + sulbactum and ceftazidime + calvulanic acid. Linzolid and vancomycin were effective in 83% and 100% cases, respectively. We conclude that similar institution-specific studies should be conducted, and such studies will be helpful in providing useful guidelines for choosing effective empirical therapy that will have a great impact on the prevention of infection and its complications in burn patients because of bacteraemia.

Burns infection profile of Singapore: prevalence of multidrug-resistant Acinetobacter baumannii and the role of blood cultures

BACKGROUND

With various changes implemented such as perioperative antibiotics for tangential excision, this retrospective study reviews the infection profile of burn patients at Singapore's only centralized burns unit. Worldwide, the appearance of multidrug-resistant (MDR) strains of Acinetobacter baumannii (A. baumannii) continues to worsen patient outcomes. This study also surveys the role of blood cultures in burns at our unit.

METHODS

Four hundred fifty-two burn patients admitted to the unit between 2011 and 2013, and with cultures performed, were included in the study. The yields of various cultures were evaluated and 2684 samples were amassed, of which 984 (36.7 %) were positive. Patient variables for predictors of MDR A. baumannii infection acquisition and bacteremia were evaluated through multivariate analyses.

RESULTS

Pseuodomonas aeruginosa (P. aeruginosa) (67 patients) was the most common organism in those with total body surface area (TBSA) burn <20 % while MDR A. baumannii (39 patients) was most prevalent in those with TBSA burn ≥20 %. We found a yield of 1.1 % positive blood cultures for TBSA burn <20 % and a yield of 18.6 % positive cultures in TBSA burn ≥20 %. The median time between surgery and bacteremia was 6.5 days (range -18 to 68 days, interquartile range 4.5); 2.9 and 8.8 % of bacteremic episodes occurred within 24 and 48 h, respectively. This is a decrease from a predeceasing study (45.3 % for 24 h and 60 % for 48 h). Multivariate analysis revealed that length of hospital stay and TBSA burn ≥20 % were predictors of MDR A. baumannii infection and positive blood cultures.

CONCLUSIONS

MDR A. baumannii infection burdens patient management, especially in those with TBSA burn ≥20 % and longer hospital stay. Prophylactic antibiotics may reduce perioperative bacteremia, but their role in MDR infections needs to be evaluated. The role of blood cultures in TBSA burn <20 % needs reconsideration.

Bloodstream infection as a predictor for mortality in severe burn patients: an 11-year study

In this study we collected and analysed data of the severe burn patients at our institution over an 11-year period in order to shed light on the controversial role of bloodstream infection (BSI) as a predictive factor for mortality in this burn population. The factors examined were age, total body surface area, smoke inhalation, presence of BSI, and BSI with resistant bacteria. In total 1081 burn patients were hospitalized from 2001 to 2011, of whom 4% died. We focused here on 158 severe burn patients, 74 of whom developed BSI, and 35 who died. Using univariate analysis, it appeared that the BSI group had a threefold greater chance of mortality compared to the non-BSI group. Patients with a Ryan score 3 had a 100% chance of mortality and those with a score 0 had 0%. Thus, focusing only on Ryan score 1 and score 2 patients, BSI did not contribute to mortality, nor was it shown to contribute to mortality in a multivariate analysis in which the score and BSI were included together. When BSI did occur, it predicted longer hospitalization periods. We conclude that BSI predicts longer length of hospitalization stay but does not contribute to the prediction of mortality beyond that offered by the Ryan score in a severe burn population.

The role of diminishing appetite and serum nesfatin-1 level in patients with burn wound infection

BACKGROUND

The burn wound represents a susceptible site for opportunistic colonization by organisms of endogenous and exogenous origin. Diminishing appetite is known to occur in patients with burn infection, yet its underlying reason is not fully understood. We have examined the levels of nesfatin 1, a protein that we consider to be a potential new treatment target for the solution of appetite and nutrition problem in patients with burn infection.

OBJECTIVES

The aim of the present study was therefore to examine nesfatin levels in patients with burn infection.

MATERIAL AND METHODS

Laboratory values, medication and dietary records, and patient notes with diagnostic information of burn wounds patients who were admitted to the Division of Burn Treatment Center were obtained from the Erzurum Region Education and Research Hospital electronic database. Post-burn wound infection was objectively assessed by culturing wound homogenates from skin tissue. The main immediate inflammatory stress response parameters assessed were serum CRP concentrations, WBC counts, and blood nesfatin concentrations.

RESULTS

Scalding was the predominant cause of burns in both categories of patients. In 19 (61.3%) burn wound infection patients, the burns were due to a scald. A significant difference was found for the nesfatin, CRP, and WBC levels between the patients and the control group (P = 0.000). A significant difference was also determined between the nesfatin, CRP, and WBC figures at the time of hospitalization and at discharge from the hospital (P = 0.000). The most predominant bacterial isolate was Pseudomonas aeruginosa 16 (51.6%) followed by Methicilline resistant Staphylococcus aureus (MRSA) 7 (22.6%).

CONCLUSIONS

We showed that the serum nesfatin 1 level was significantly lower in the patients with burn than in the control group in our study. We considered that the central nesfatin 1 system should be taken into consideration, rather than the peripheric nesfatin 1 system, when considering the regulation of appetite in patients with burns and particularly those accompanied by infection. In other explanation of the observed negative correlation between nesfatin 1 and burn wound infection suggests that nesfatin 1 may indicate the possible contribution of nesfatin 1 to the energy homeostasis.

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.

Blood stream infections (BSI) in severe burn patients--early and late BSI: a 9-year study

Bloodstream infections (BSI) and sepsis are among the most common complications occurring in severe burn patients. This study was designed to evaluate changes in BSI pathogens over almost a decade in severe burn patients at Rambam Healthcare Campus, and BSI occurrence during early and late hospitalization periods. Retrospective computerized data was retrieved from all severe burn patients hospitalized in our institution during the years 2001-2009. BSI in the first week was defined as early BSI, and in the second week and beyond, late BSI. Of 159 severe burns patients, 74 had at least one BSI episode. Most first BSI episodes were diagnosed during the first week of hospitalization. In late BSI, an increased prevalence of resistant bacteria (methicillin-resistant Staphylococcus aureus [MRSA], carbapenem-resistant Klebsiella pneumoniae [CRKP], imipenem-resistant Pseudomonas aeruginosa [PSE-IMP]) and Candida spp. were observed. However, over the 9-year study period, only CRKP increased significantly. In summary, except for the sudden appearance and increase in CRKP (8% increase; p=0.045), we did not observe a significant change in the BSI pathogen profile over the 9-year period. Nevertheless, over the hospitalization period, there is a clear change in the BSI bacteria profile, especially after 4 weeks of hospitalization.

The prevalence of antimicrobial resistance in clinical isolates from Gulf Corporation Council countries

Background

The burden of antimicrobial resistance worldwide is substantial and is likely to grow. Many factors play a role in the emergence of resistance. These resistance mechanisms may be encoded on transferable genes, which facilitate the spread of resistance between bacterial strains of the same and/or different species. Other resistance mechanisms may be due to alterations in the chromosomal DNA which enables the bacteria to withstand the environment and multiply. Many, if not most, of the Gulf Corporation Council (GCC) countries do not have clear guidelines for antimicrobial use, and lack policies for restricting and auditing antimicrobial prescriptions.

Objective

The aim of this study is to review the prevalence of antibiotic resistance in GCC countries and explore the reasons for antibiotic resistance in the region.

Methodology

The PubMed database was searched using the following key words: antimicrobial resistance, antibiotic stewardship, prevalence, epidemiology, mechanism of resistance, and GCC country (Saudi Arabia, Qatar, Bahrain, Kuwait, Oman, and United Arab Emirates).

Results

From January1990 through April 2011, there were 45 articles published reviewing antibiotic resistance in the GCC countries. Among all the GCC countries, 37,295 bacterial isolates were studied for antimicrobial resistance. The most prevalent microorganism was Escherichia coli (10,073/44%), followed by Klebsiella pneumoniae (4,709/20%), Pseudomonas aeruginosa (4,287/18.7%), MRSA (1,216/5.4%), Acinetobacter (1,061/5%), with C. difficile and Enterococcus representing less than 1%.

Conclusion

In the last 2 decades, E. coli followed by Klebsiella pneumoniae were the most prevalent reported microorganisms by GCC countries with resistance data.

CCL1 released from M2b macrophages is essentially required for the maintenance of their properties

Patients with 10-30 days postburn injury are greatly susceptible to infections. M1M (IL-10(-)IL-12(+) M) are essential cells in host antibacterial innate immunity against MRSA infections. However, these effector cells are not easily generated in hosts who are carriers of M2bM (IL-12(-)IL-10(+)CCL1(+)LIGHT(+) M). M2bM are inhibitory on M1M generation. In this study, the antibacterial resistance of mice, 10-30 days postburn injury against MRSA infection, was improved by the modulation of M2bM activities. Unburned mice inoculated with M preparations from mice, 10-30 days after burn injury, were susceptible to MRSA infection, whereas unburned mice, inoculated with M preparations from the same mice that were previously treated with CCL1 antisense ODN, were resistant to the infection. M2bM, isolated from Day 15 burn mice, lost their M2bM properties 3 days after cultivation under frequent medium changes, whereas their M2bM properties remained in the same cultures supplemented with rCCL1. In cultures, M preparations from Day 15 burn mice treated with CCL1 antisense ODN did not produce CCL1 and did convert to M1M after heat-killed MRSA stimulation. Also, Day 15 burn mice treated with the ODN became resistant against MRSA infection. These results indicate that CCL1 released from M2bM is essentially required for the maintenance of their properties. The increased susceptibility of mice, 10-30 days after burn injury to MRSA infection, may be controlled through the intervention of CCL1 production by M2bM appearing in association with severe burn injuries.

Comparison of the antibacterial effect of silver sulfadiazine 1%, mupirocin 2%, Acticoat and octenidine dihydrochloride in a full-thickness rat burn model contaminated with multi drug resistant Acinetobacter baumannii

In this study, our aim is to compare the efficacy of different topical antibacterial agents in a rat model contaminated with a multi drug resistant (MDR) standard Acinetobacter baumannii strain. The study was carried out on 40 Sprague-Dawley rats of 250-300 g each. For the purposes of this study, the rats were divided into 5 groups, with 8 rats in each group: Group 1 control; Group 2 silver sulfadiazine; Group 3 mupirocin; Group 4 Acticoat group; and Group 5 octenidine dihydrochloride group. Following to the formation of the full-thickness burn areas in rats, the MDR A. baumannii standard strain was inoculated into the burned area. The rats in all the groups were sacrificed at the end of the 10th day and subjected to histopathological and microbiological evaluation. In the histopathological evaluation, the lowest inflammatory cell response and bacterial density in the eschar and muscle tissues were observed in the Acticoat group. While these results were found to be statistically significant compared to the silver sulfadiazine group, only the bacterial density in the muscle tissue was found as significant in comparison to the mupirocin and octenidine groups. In the microbiological evaluation, the lowest growth in the muscle tissue culture among all the groups was observed in the Acticoat group. The growth in the eschar tissue culture was significantly lower in the Acticoat and octenidine groups in comparison to the silver sulfadiazine group. At the end of the study, it has been observed that Acticoat was effective both in eschar and muscle, while octenidine was effective in eschar tissues in a rat burn model contaminated with MDR A. baumannii.

Comparison of mortality associated with sepsis in the burn, trauma, and general intensive care unit patient: a systematic review of the literature

The purpose of this systematic review of the literature was to determine the association of sepsis with mortality in the severely injured adult patient by means of a comparative analysis of sepsis in burn and trauma injury with other critically ill populations. The MEDLINE (PubMed), Cochrane Library, and ProQuest databases were searched. The following keywords and MeSH headings were used: "sepsis," septicemia," "septic shock," "epidemiology," "burns," "thermal injury," "trauma," "wounds and injuries," "critical care," "intensive care," "outcomes," and "mortality." Included studies were clinical studies of adult burn, trauma, and critically ill patients that reported survival data for sepsis. Thirty-eight articles were reviewed (9 burn, 11 trauma, 18 general critical care). The age of burn (<45 years) and trauma (34-49 years) groups was lower than the general critical care (57-64 years) population. Sepsis prevalence varied with trauma-injured patients experiencing fewer episodes (2.4%-16.9%) contrasted with burn patients (8%-42.5%) and critical care patients (19%-38%). Survival differed with trauma patients experiencing a lower rate of mortality associated with sepsis (7%-36.9%) compared with the burn (28%-65%) and critical care (21%-53%) groups. This study is the first to compare sepsis outcomes in three distinct patient populations: burn, trauma, and general critical care. Trauma patients tend to have relatively low sepsis-associated mortality; burn patients and the older critical care population have higher prevalence of sepsis with worse outcomes. Great variability of criteria to identify septic patients among studies compromises population comparisons.

Epidemiology of bloodstream infections in burn-injured patients: a review of the national burn repository

Bloodstream infections (BSIs) are a major cause of morbidity and mortality in thermally injured patients. However, these infections have not been well defined in this patient population. Therefore, the authors performed a retrospective case-control study to characterize the epidemiology, microbiology, and outcomes of burn-associated BSIs. A retrospective review of all patients in the National Burn Repository (NBR) between the years 1981 and 2007 was performed. All cases that had infection listed under complications were included in this study. For each case, two randomly selected patients from the same time period served as controls. Patient demographic data, extent of %TBSA, and type of infection were extracted. Primary end point was mortality. Secondary endpoints were hospital length of stay (LOS), intensive care unit LOS, total ventilator days, and hospital charges. Further analysis of the data involved case-matching patients by TBSA deciles, adjustment for the effects of TBSA and other potential confounders, and a sensitivity analysis of the effects of including or excluding sites that might have failed to consistently capture BSI information. A total of 11,793 patients (3931 cases and 7862 control) were included in the study. Of cultures revealing a Gram-positive organism, Staphylococcus aureus (32%) was the most common. From samples where isolation of a Gram-negative species occurred, Pseudomonas aeruginosa (35%) was more prominent. Infected patients were older (40.9 vs 32.8, P < .05) and had higher %TBSA (22.2 vs 7.9, P < .05). BSI was associated with significantly higher mortality (21.9% vs 3.09%), hospital LOS (47.4 vs 8.8 days) intensive care unit LOS (30.8 vs 2.6 days), ventilator days (29.2 vs 1.4 days), and hospital charge ($339,909.91 vs $33,272.43); P < .001 for all values. On evaluation of case-matched controls, mortality was higher for patients with BSI only <50% TBSA strata. Conclusions were unaffected by adjustment for TBSA and other possible confounders and was not influenced by possible failure of some sites to consistently capture BSI information. Development of BSI in hospitalized burn patients is associated with significant increases in morbidity, mortality, and resource utilization.

Acinetobacter infections: a growing threat for critically ill patients

There has been increasing concern regarding the rise of Acinetobacter infections in critically ill patients. We extracted information regarding the relative frequency of Acinetobacter pneumonia and bacteraemia in intensive-care-unit (ICU) patients and the antimicrobial resistance of Acinetobacter isolates from studies identified in electronic databases. Acinetobacter infections most frequently involve the respiratory tract of intubated patients and Acinetobacter pneumonia has been more common in critically ill patients in Asian (range 4-44%) and European (0-35%) hospitals than in United States hospitals (6-11%). There is also a gradient in Europe regarding the proportion of ICU-acquired pneumonias caused by Acinetobacter with low numbers in Scandinavia, and gradually rising in Central and Southern Europe. A higher proportion of Acinetobacter isolates were resistant to aminoglycosides and piperacillin/tazobactam in Asian and European countries than in the United States. The data suggest that Acinetobacter infections are a growing threat affecting a considerable proportion of critically ill patients, especially in Asia and Europe.

Analysis of anaerobic blood cultures in burned patients

The utility of anaerobic blood culturing is often debated in the general population, but there is limited data on the modern incidence, microbiology, and utility of obtaining routine anaerobic blood cultures for burned patients. We performed a retrospective review of the burned patients electronic medical records database for all blood cultures drawn between January 1997 and September 2005. We assessed blood cultures for positivity, organisms identified, and growth in aerobic or anaerobic media. 85,103 blood culture sets were drawn, with 4059 sets from burned patients. Three hundred and forty-five single species events (619 total blood culture isolates) were noted in 240 burned patients. For burned patients, four isolates were obligate anaerobic bacteria (all Propionibacterium acnes). Anaerobic versus aerobic culture growth was recorded in 310 of 619 (50.1%) burned patient blood culture sets. 46 (13.5%) of the identified organisms, most of which were not obligate anaerobic bacteria, were identified from solely anaerobic media. The results of our study suggest that the detection of significant anaerobic bacteremia in burned patients is very rare and that anaerobic bottles are not needed in this population for that indication. However anaerobic blood cultures systems are also able to detect facultative and obligate aerobic bacteria; therefore, the deletion of the anaerobic culture medium may have deleterious clinical impact.

Outcomes of Acinetobacter baumannii infection in critically ill burned patients

The objective of this study was to determine the incidence of drug resistance among isolates of Acinetobacter baumannii from our Burn Intensive Care Unit (BICU), the rate of clinical cure, and the mortality rate. We undertook a retrospective review of all cases of infection from the BICU between January 2004 and November 2005. The group consisted of 24 men (80%) and 6 women with a mean age of 43 years (range, 17-76 years, +/-14.5 years). Mean TBSA burned was 43% (range, 9-75%, +/-19%). Mean BICU length of stay was 49 days (range, 5-118 days, +/-30 days). Patients developed their first infection after a mean of 16 days (5-73 days, +/-14 days). The initial site of infection was bronchoalveolar lavage in 21 (70%), blood in 6 (20%), central venous catheter tip in 2 (7%), and urine in 1 (3%). The isolates displayed resistance to imipenem in 87% of cases. No organism displayed resistance to colistin (polymixin E). Patients were treated with colistin in 20 cases (67%), with amikacin in 8 cases (27%), and with imipenem in 2 cases (7%). A total of 10 patients (33%) died, 1 from gastrointestinal bleeding and 9 from active infection, giving an infection related mortality of 30%. In 21 cases (70%), a cure was achieved with a mean duration of treatment of 16 days (range, 4-30 days, +/-7 days). The majority of A. baumannii isolates were multidrug resistant; however, no isolate displayed resistance to colistin. Cure rate was 70% and infection-related mortality reached 30%. More investigation is warranted to improve prevention and to assess new therapeutic agents.

Septicemia as a cause of death in burns: an autopsy study

In burn victims, invasion by the bacteria is not unexpected, despite advances in antibiotics, and it has been reported that in the absence of topical therapy, the superficial areas of burn wound contain up to 100 million organisms per gram of tissue within 48h following the injury. We examined the autopsy reports of 334 cases who died because of complicated burns and who underwent medico-legal autopsy during a period of 5 years to study the rate of infection/sepsis. It was observed that in 65% of fatal burn cases, septicemia was the cause of death. Pseudomonas aeuroginosa and Klebsiella sp. were the most common organism, isolated either singly or in combination in 29% and 28% cases, respectively. High mortality from burns in young married women has been recognized as an alarming and contentious problem in India, particularly among the low socio-economic groups. We found that the females aged 21-25 were the most common victims accounting for 37% of burn fatalities due to septicemia. It was concluded that to carry out periodic review of patterns of isolation and susceptibility profiles of microorganisms infecting burn wounds should be a routine in all burn units. In view of the limited resources of developing countries, we recommend the use of available scoring systems to estimate burn outcome so that the best care can be directed to those who have a better chance of improvement.

Fatores de risco da sepse em pacientes queimados

OBJETIVO: Os avanços no tratamento de queimados têm reduzido as taxas de mortalidade e melhorado a qualidade de vida das vítimas de queimaduras. Entretanto, a sepse continua sendo um desafio e umas das principais causas de óbito no queimado. O objetivo deste trabalho é investigar, através de um estudo caso-controle, os fatores de risco da sepse em pacientes queimados. MÉTODO: O estudo caso-controle foi conduzido durante 12 meses, compreendendo os pacientes que foram tratados em regime de internação hospitalar na Unidade de Queimados do Hospital Regional da Asa Norte (HRAN), Brasília-DF. RESULTADOS: Quarenta e nove (19,4%) pacientes tiveram sepse, de um total de 252 queimados internados na Unidade de Queimados durante o periodo do estudo. Eles tiveram um ou no maximo tres episodios de sepse durante a internacao, totalizando 62 episodios. Vinte e seis (53,1%) eram homens e a media de idade foi de 21,9 ± 18,9 anos (variacao de um a 89 anos). A superficie corporal queimada dos pacientes que tiveram sepse variou de sete a 84%, com uma media de 37,7 ± 18,4%, sendo significativamente superior aos controles. As principais bacterias causadoras de sepse foram Staphylococcus aureus (46,5%), Staphylococcus coagulase negativo (20,7%), Acinetobacter baumannii (12,1%) e Enterobacter cloacae (12,1%). Trinta (61,2%) pacientes tiveram seu primeiro episodio de sepse na primeira semana de internacao. Quanto aos fatores de risco para a ocorrencia de sepse, destacam-se os seguintes, conforme seu poder de associacao "odds ratio": o uso de tres ou mais cateteres, a presenca de duas ou mais complicacoes, a superficie corporal queimada > 30%, o agente chama aberta e o sexo feminino. No geral, a taxa de letalidade por sepse foi de 24,5%. CONCLUSÃO: Um melhor conhecimento dos fatores de risco da sepse no paciente queimado permite o tratamento precoce dessa complicação, com antibioticoterapia sistêmica adequada, contribuindo para reduzir a morbidade e a mortalidade desses pacientes.

Contamination of environmental surfaces by Staphylococcus aureus in a dermatological ward and its preventive measures

We investigated contamination of environmental surfaces by Staphylococcus aureus from April 1 to the end of June in 2002 in the dermatological ward (37 beds) of a university hospital. For surfaces contaminated by high levels of S. aureus, disinfection methods were evaluated. 100-10(5) colony forming units (cfu) of methicillin-resistant S. aureus (MRSA) or methicillin-sensitive S. aureus (MSSA) were detected on items such as an immersion bathtub (examined area, about 900 cm2), foot washbowl, stretcher for an immersion bath, and chair for the shower. After disinfection, no S. aureus was detected on smooth surfaces such as the immersion bathtub and foot washbowl; however, S. aureus was detected even after disinfection on porous surfaces made of sponge-like materials (polyethylene foam) such as the stretcher for the immersion bath and the shower chair. Scanning electron microscopy of the porous surfaces showed formation of a large amount of coccus and bacillus biofilms on the walls of pores in the multi-pore structure. Material that is porous should not be used in patient care settings because it is not possible to disinfect it properly.

Predicting factors influencing the fatal outcome of burns in Kuwait

A prospective study was carried out on a total of 2111 burn patients admitted at the Burn Center in Kuwait, during 1993 to 2001, with the purpose of predicting the risk factors influencing the fatal outcome. A total of 111 (5.3%) patients died, giving an annual average of 12 deaths, and a mortality rate of 0.64/100,000 population. The data, from the in-patient records, included the most commonly available demographic features viz. age, gender and nationality, as well as best recorded clinical factors, such as cause of burn, total body surface area (TBSA), duration of hospital stay and outcome, for analysis. Kolmogorov-Smirnov z test showed the median age (30 years) and TBSA (80%) significantly higher (p < 0.001) among those died as compared to 24 years and 10%, respectively in patients survived. The Chi-square test revealed a fatal outcome associated with gender and cause of burn. The multiple logistic regression model predicted patients, aged 60 years and above (OR: 9.9, p < 0.001), female gender (OR: 2.2, p < 0.016), Flame burns (OR: 3.5, p < 0.035), and TBSA > 90% (OR: 23.5, p < 0.001), as the most influencing risk factors for a fatal outcome at this burn center. Patients with these characteristics need to be given special attention during in-patient care.

Sepsis in burned patients

A prospective study was conducted from June 2001 to May 2002 at the Burns Unit of Hospital Regional da Asa Norte, Brasília, Brazil. During the period of the study, 252 patients were treated at the Burns Unit, 49 (19.4%) developed clinically and microbiologically proven sepsis. Twenty-six (53.1%) were males and 23 (46.9%) females with a mean age of 22 years (range one to 89 years) and mean burned body surface area of 37.7 +/- 18.4% (range 7 to 84%). Forty-three patients had flame burns, five a scald and one an electric burn. These 49 patients had a total of 62 septic episodes. Forty (81.6%) patients had only one and nine (18.4%) had up to three episodes of sepsis. Thirty (61.2%) patients had their first septicemic episode either earlier or by one week postburn. Out of 62 septic episodes, 58 were due to bacteria and four due to Candida sp. The most common bacteria isolated from blood culture were Staphylococccus aureus, coagulase-negative Staphylococcus, Acinetobacter baumannii, Enterobacter cloacae and Klebsiella pneumoniae. Eleven (18.9%) episodes were due to oxacillin resistant Staphylococcus aureus. Acinetobacter baumannii was sensitive to ampicillin/sulbactam in 71.4% and to imipenem in 85.7% of the cases. The primary foci of sepsis were the burn wound in 15 (24.2%) episodes. The most common clinical findings of sepsis in these patients were fever, dyspnea, hypotension and oliguria. The most common laboratory findings of these patients were anemia, leukocytosis, hypoalbuminemia and thrombocytopenia. Twelve (24.5%) patients died. The appropriate knowledge of clinical, epidemiological, laboratorial and microbiological aspects of sepsis in burned patients permits an adequate diagnosis and treatment of this complication.

Burn septicaemia in Kuwait: associated demographic and clinical factors

OBJECTIVE

To study the demographic and clinical factors associated with burn septicaemia patients in Kuwait.

MATERIALS AND METHODS

All burn in-patients, who developed septicaemia at the Burns Unit, Al-Babtain Centre for Burns and Plastic Surgery, Kuwait, during a 9-year period (June 1992 to May 2001) were included in the study. The data were recorded for age, sex, nationality, cause and percentage of burns, inhalation injury, resuscitation, number of episodes, septicaemia on post-burn day, the microorganisms responsible in each episode, treatment and outcome for statistical analysis. Using SPSS (PC version 11.0) software, a probability level of p < 0.05 was considered significant.

RESULTS

Of the 2,082 patients treated in the Burns Unit, 166 [8%; 99 (60%) males and 67 (40%) females] with a mean age of 26 years (range 1-70) had septicaemia. Significantly higher (p < 0.001) cases were recorded among Kuwaiti children (< or =14 years) and non-Kuwaitis (25-59 years) than other corresponding age groups. The total body surface area burned ranged from 2 to 95% (mean 42%) and the main cause of burn was flame (77.1%). Inhalation injury was diagnosed in 39 (23.5%) patients. A total of 253 septicaemic episodes occurred in all patients. The majority, 123 (74.1%), had a single episode and the remaining 43 (25.6%) had multiple (2-10) episodes. One hundred and fifty-five (61.3%) episodes were due to gram-positive organisms, mainly methicillin-resistant Staphylococcus aureus, and 32 (12.7%) were polymicrobial. One hundred and twenty-four (74.7%) patients had wound excision and skin grafting procedures and their survival was significantly higher (OR = 4.3; 95% CI: 1.98-9.31) than non-surgically treated patients. Thirty-nine (23.5%) patients died mainly due to multi-organ failure.

CONCLUSION

The findings indicate that the patients with extensive flame burns were prone to developing septicaemia due mainly to gram-positive bacteria. The surgical excision of eschar and wound covering improved the outcome of the patients while prophylactic antibiotic treatment had no role in the incidence and outcome of the burn patients.

Injury primes the innate immune system for enhanced Toll-like receptor reactivity

Severe injury causes a dramatic host response that disrupts immune homeostasis and predisposes the injured host to opportunistic infections. Because Toll-like receptors (TLRs) recognize conserved microbial Ags and endogenous danger signals that may be triggered by injury, we wanted to determine how injury influences TLR responses. Using an in vivo injury model, we demonstrate that injury significantly increased TLR2- and TLR4-induced IL-1beta, IL-6, and TNF-alpha production by spleen cells. This influence of injury on TLR reactivity was observed as early as 1 day after injury and persisted for at least 7 days. The outcome of similar studies performed using TLR4-mutant C57BL/10ScN/Cr mice revealed that TLR2 responses remained primed, thus suggesting that injury-induced priming can occur independently of endogenous TLR4 signaling. Increased TLR4 reactivity was also observed in vivo, because LPS-challenged injured mice demonstrated significantly higher cytokine expression levels in the lung, liver, spleen, and plasma. Macrophages and dendritic cells were the major source of these cytokines as judged by intracellular cytokine staining. Moreover, ex vivo studies using enriched macrophage and dendritic cell populations confirmed that T cells did not contribute to the enhanced TLR2 and TLR4 responses. The results of flow cytometry studies using TLR2- and TLR4-MD-2-specific Abs indicated that injury did not markedly alter cell surface TLR2 or TLR4-MD-2 expression. Taken together, these findings establish that injury primes the innate immune system for enhanced TLR2- and TLR4-mediated responses and provides evidence to suggest that augmented TLR reactivity might contribute to the development of heightened systemic inflammation following severe injury.

Incidence of urinary tract and bloodstream infections in Ghotbeddin Burn Center, Shiraz 2000-2001

Though burn wound infections have been extensively studied, other nosocomial infections (NIs) in burn patients have received less attention. Invasive diagnostic procedures (vascular and bladder catheterization) make the burn patients more susceptible to different nosocomial infections. The aim of this study was to determine the rate of bloodstream and urinary tract infections associated with i.v. line and urinary catheter (UC) in Ghotbeddin Burn Center and also to compare these rates with those of the National Nosocomial Infections Surveillance System (NNIS) in the USA. This study was conducted over 11 months, from 21st December 2000 to 21st November 2001. All the patients who were admitted for more than 48 h and did not have evidence of infection at the time of admission were included in the study. For diagnosis of urinary tract and bloodstream infections, the standard definitions from the Center for Diseases Control (CDC) were used. Of the total 106 qualifying patients, 91 study patients acquired nosocomial infections (85.85%). Urinary catheter-associated urinary tract infection (UC-UTI) rate was 30 per 1000 urinary catheter days and i.v. line-associated bloodstream infection (i.v. line-BSI) rate was 17 per 1000 i.v. line days. Comparison of incidence rates of UC-UTI and i.v. line-BSI in Ghotbeddin Hospital and NNIS showed that rate of infection to be higher in Ghotbeddin Hospital while device utilization ratio (urinary catheter and central line) was higher in the NNIS hospitals. To reduce the rate of infection at Ghotbeddin Burn Center, education, development of standardized guidelines for the use of invasive devices and introduction of a nosocomial infections surveillance system are necessary.

Septicaemia after burn injury: a comparative study

Seventy-nine (8.4%) patients during June 1992-May 1996 (Group-1) and 68 (7.2%) patients from June 1996 to May 2000 (Group-2) who developed septicaemia at the burns unit of Al-Babtain Centre for Plastic Surgery and Burns, Kuwait, were retrospectively studied and compared. The mean age of 26 years, male predominance, flame burns as main aetiology and mean burn percentage of >or=40% was observed in both the groups. Both groups revealed extensive flame burn, inhalation injury, intubation and difficult resuscitation as the risk factors. The proportion of satisfactory resuscitation increased significantly (P<0.001) in Group-2. The septicaemia commonly occurred within 2 weeks postburn but the number of episodes during 5 days postburn was less in Group-2. The surface wound was found to be the likely source of entry of the organisms into the blood stream in both the groups. The gram positive organisms were dominant aetiologic factor in both groups but an increase frequency of Acnetobacter was found in Group-2. The proportion of MRSE and Pseudomonas septicaemia was significantly higher (P<0.01) in the Group-1. The rate of survivors, in both the groups was higher among operated patients but it was significantly higher (P<0.001) in the Group-1. A mortality rate 20.6% in Group-2 decreased against Group-1, which can be attributed to better resuscitation, nutritional care, early detection of septicaemia, appropriate antibiotics and early wound excision and skin grafting. MOF was the cause of death of 60.9% in Group-1 and 85.7% in Group-2. There was no role of prophylactic antibiotic in burn patients in the incidence of septicaemia and mortality.

Glycyrrhizin restores the impaired IL-12 production in thermally injured mice

Mice 6 days after thermal injury (TI-mice) did not respond to lipopolysaccharide (LPS) stimulation for production of serum interleukin 12 (IL-12; 2 h after LPS stimulation, <20 pg/ml in TI-mice; 1091+/-162 pg/ml in normal mice). However, 2 h after LPS stimulation, 1456+/-118 pg/ml of IL-12 were demonstrated in sera of TI-mice previously treated with a 10 mg/kg i.p. dose of glycyrrhizin (GR). IL-12 was not induced by LPS in sera of normal mice inoculated with burn-associated type 2 T cells (IL-4/IL-10-producing CD8+CD11b+TCRgamma/delta+T cells isolated from spleens of TI-mice). However, IL-12 production was induced by LPS in sera of these mice previously treated with GR or a mixture of monoclonal antibodies (mAbs) for type 2 cytokines. Also, IL-12 production was induced by LPS in TI-mice inoculated with CD4+T cells from spleens of GR-treated normal mice (GR-CD4+T cells, 5x10(6)cells/mouse). Since GR-CD4+T cells have been shown to be antagonistic cells against production of type 2 cytokines by burn-associated type 2 T cells, these results indicate that IL-12 unresponsiveness shown in TI-mice is recovered by GR through the regulation of burn-associated type 2 T cell responses.

Burn mortality during 1982 to 1997 in Kuwait

The study group is comprised of 234 patients (6.4%) who died out of 3680 patients treated for burn injuries during the period January 1982 to December 1997 in Kuwait. There were 112 (47.9%) males and 122 (52.1%) females and their mean age was 30 years (range 1-93) when compared with 24 years among survivors. The high mortality amongst two age groups 0-5 years (39 deaths, 16.7%) and 16-35 years (109 deaths, 46.6%) shows their vulnerability in the society. In 190 patients (81.2%) the burn injuries occurred at home. A total of 216 patients (92.3%) sustained flame burns mainly due to clothes on fire (40.6%) and cooking gas accidents (25.2%), and in 18 patients (7.7%) the burns were due to scalds. The suicidal burns occurred in 22 female and 5 male patients mainly of younger age groups. The mean percentage of burns was 71% (range 9-100%) as against 20% amongst survivors, and 195 patients (83.3%) had > or = 50% total body surface area (TBSA) burn. Four patients (1.7%) had superficial dermal burns, 94 (40.2%) had full thickness and 136 (58.1%) had mixed with full thickness burns predominance. The associated inhalation injury was diagnosed in 132 patients (56.4%). A total of 61 patients (26.1%) had either single or multiple pre-existing diseases and 51 of them sustained flame burns. The day of death varied from 1 to 103 days (mean 16 days) but 58 patients (24.8%) died within 48 hours of post burn. A total of 120 patients (51.3%) died due to septicaemia, 83 (35.5%) due to renal failure, 28 (10.2%) due to multi-organ failure, and 7 (3.0%) due to bronchopneumonia. The overall mortality rate was 6.4%, but this has significantly lowered to 4.4% (p = < 0.01) during last four years probably due to better burn care. The study thus shows that age group 0-5 and 16-35 years, domestic accidents, flame burn, inhalation injury, and pre-existing diseases are risk factors and septicaemia as the dominant cause of death in our patients.

Expansion technique for skin grafts (Meek technique) in the treatment of severely burned patients

The important limiting factor in the treatment of the severely burned patient is the lack of autograft donor skin. The method of obtaining uniform widely expanded postage stamp autografts described by Meek in 1963 has been evaluated in this study amongst seven severely burned patients. The expansion ratio of 1:4, 1:6, 1:9 was mostly used. After the removal of polyamide gauze on seventh post-operative day the autografts island were covered with overlay allograft, if the expansion ratio of 1:6 and above was used. The mean epithelialization rate was 90% within 4-5 weeks. The preliminary experience suggests, and proves that, it is a method of choice in severely burned patients.

Bacteriology in burn patients undergoing mechanical ventilation

In this paper the authors introduce a retrospective study of the incidence of infectious processes in the Burns Unit of the Cruces Hospital (Bilbao), in those patients treated between 1995 and 1998, and who needed, for different reasons, mechanical ventilatory support. The most common microorganisms found in wound cultures, plugged telescoping catheter and blood cultures and analyse variations throughout the stay in the Burns Unit are described.

Nosocomial infections in an Iranian burn care center

Burn patients are obviously at high risk for nosocomial infections due to the immunocompromizing effects of burn injury. Pseudomonas aeruginosa is an important life-threatening nosocomial pathogen in burn units. The aim of this study was to determine nosocomial infections in the Tohid Burn Center in Tehran, Iran. Materials of this study were samples of burn wounds and blood from 582 patients who required hospitalization during March 1996 and September 1998. Burn wound samples were taken on admission day, 3 and 7 days after admission. Frequency of culture positive on admission day, 3 and 7 days after admission were 15, 66, and 88%, respectively. Frequency of P. aeruginosa and Staphylococcus aureus on admission day were 35 and 34%, on the third day after admission 73 and 15%, and at the end of the first week of admission 87 and 9%, respectively. Frequency of blood culture positive was 36% (19/53) of which 89% were P. aeruginosa. Overall mortality rate was 18.5% (108/582). Of these patients, frequency of positive wound culture was 92% (99/108). In conclusion, our results show that P. aeruginosa is the leading cause of nosocomial infections in our burn center. It is also necessary to introduce urgent measures for restriction of the spread of P. aeruginosa infections in our burn center.

Comparison of systematic versus selective screening for methicillin-resistant Staphylococcus aureus carriage in a high-risk dermatology ward

OBJECTIVE

To compare two strategies for screening methicillin-resistant Staphylococcus aureus (MRSA) carriers in a high-risk dermatology ward: systematic screening of all admitted patients versus selective screening of patients at risk.

DESIGN

The two strategies were applied prospectively during two consecutive periods. In period A (8.5 months), only patients transferred from other wards, or with a history of prior hospitalization, or presenting chronic wounds or disease with denuded skin were considered at high risk of MRSA carriage and sampled. In period B (7.5 months), all admitted patients were systematically screened. End-points were the number of patients having a MRSA-positive screening sample on admission during period B and having none of the risk factors used in period A, the rate of imported MRSA cases, and the rate of acquired cases.

SETTING

A 1,032-bed university hospital with a 19-bed inpatient dermatology ward, a referral center for toxic epidermal necrolysis and severe extensive dermatoses.

PATIENTS

The study included 729 dermatology inpatients (370 in period A and 359 in period B).

RESULTS

During period A, screening samples were obtained on admission for 30% of patients (77% of the patients at risk) and identified 25 MRSA carriers. During period B, 90.5% of admitted patients were screened, and 26 MRSA carriers were detected on admission; all of these patients belonged to at least one predefined category at risk for carriage. Overall rates of imported and acquired cases were similar between the two periods (6.8% vs 7.5%, and 2.9% vs 2.4%, respectively).

CONCLUSIONS

A screening strategy targeted to patients at risk of harboring MRSA has similar sensitivity and is more cost-effective than a strategy of systematic screening to identify MRSA carriers on admission.

Crystal structure of Pseudomonas aeruginosa PAK pilin suggests a main-chain-dominated mode of receptor binding

Fibers of pilin monomers (pili) form the dominant adhesin of Pseudomonas aeruginosa, and they play an important role in infections by this opportunistic bacterial pathogen. Blocking adhesion is therefore a target for vaccine development. The receptor-binding site is located in a C-terminal disulphide-bonded loop of each pilin monomer, but functional binding sites are displayed only at the tip of the pilus. A factor complicating vaccination is that different bacterial strains produce distinct, and sometimes highly divergent, pilin variants. It is surprising that all strains still appear to bind a common receptor, asialo-GM1. Here, we present the 1.63 A crystal structure of pilin from P. aeruginosa strain PAK. The structure shows that the proposed receptor-binding site is formed by two beta-turns that create a surface dominated by main-chain atoms. Receptor specificity could therefore be maintained, whilst allowing side-chain variation, if the main-chain conformation is conserved. The location of the binding site relative to the proposed packing of the pilus fiber raises new issues and suggests that the current fiber model may have to be reconsidered. Finally, the structure of the C-terminal disulphide-bonded loop will provide the template for the structure-based design of a consensus sequence vaccine.

Staphylococcal septicaemia in burns

This study analyses staphylococcal septicaemia in a series of 1516 burn patients who were admitted to the burn unit of the Al-Babtain Centre for Burns and Plastic Surgery, Ibn Sina Hospital, Kuwait over a period of 6.5 years (1 June 1992-31 December 1998). One hundred and nine patients (7.2%) developed clinically and microbiologically proven septicaemia, of which 80 (73.4%) showed one or the other type of Staphylococcus in their blood. Fifty (62.5%) of them were males and 30 (37.5%) females, with a mean age of 26 years and the mean total body surface area of burns (TBSA) of 45% (range 1-93%). Preschool age children comprised 27.5% of the patients. Flame was the dominant (80%) cause of burn. Of the 80 patients who had 91 episodes of septicaemia, 52 (65%) had MRSA, 8 (10%) MSSA, 11 (13.8%) MRSE and 5 (6.2%) MSSE and 4 (5%) others had mixed organisms. Only the patients with MRSA had multiple episodes. Eight patients (10%) showed septicaemic episodes within only 48 h of admission; however, the majority of the patients (77.5%) had a septicaemic attack within 2 weeks postburn. Of the 52 MRSA septicaemic cases, 39 (75%) survived and 13 (25%) died. Four patients with septicaemia due to mixed infections died. A total of 19 patients were intubated, 14 due to inhalation injury and 5 because of septicaemia; all in the former group died. Glycopeptide therapy (vancomycin/teicoplanin) was instituted immediately following the detection of staphylococci in the blood. No significant difference was noted in relation to mortality amongst the septicaemic patients, whether or not on prophylactic antibiotic. Fifty-six (70%) of the 80 patients had 139 sessions of skin grafting and survived. Of the 52 MRSA patients, 40 had 101 sessions of skin grafting and 33 of them survived. The apparent low mortality was probably due to early detection of the organism, appropriate antibiotic therapy, care for nutrition and early wound cover. This study indicates a high incidence of staphylococcal septicaemia (especially due to MRSA) in the burn unit. A surface wound is the likely source of entry to the blood stream in these immunocompromised patients. The organism could be detected in blood as early as 48 h postburn and in as little TBSA burn as 1% in this MRSA endemic unit. Inhalation injury with major burns and added staphylococcal septicaemia invariably proved to be fatal.

Pseudomonas aeruginosa septicaemia in burns

Out of 1415 patients treated as inpatients at Al-Babtain Center for Burns and Plastic Surgery, Ibn Sina Hospital, Kuwait spanning over a period of 6 years from June 1992 to June 1998, 102 developed clinically and microbiologically proven septicaemia. Only 15 out of them had either single or multiple episodes of septicaemia due to Pseudomonas aeruginosa and were studied during their stay in the hospital. Five of them were males and 10 females, with a mean age of 26 years (range 3-51 years) and mean total body surface area of burns (TBSA) of 66% (range 25-90%). All of them had flame burns and resuscitation was found to be difficult in eight patients either due to delayed hospitalization or accompanied inhalation injury. Seven patients were intubated, four due to inhalation injury and three for septicaemic complications. Among the 15 patients under study, a total of 36 septicaemic episodes were detected of which 21 were due to P. aeruginosa. This organism was found in the first episodes in nine patients, in second episodes in six, in third episodes in three and fourth, fifth and sixth episodes in one patient, each at a variable postburn day. Ten patients had 38 sessions of excision and skin grafting, six of them survived. Nine of the 15 patients under study died due to septicaemia, but only six of them had P. aeruginosa as the last isolate. Except for one, all patients had > 40% TBSA burn, two had difficult resuscitation and four were intubated. The day of death varied between 3 to 52 days postburn (mean 19 days). This study showed that females with flame burns are susceptible to P. aeruginosa septicaemia. Difficult resuscitation and intubation also proved to be important risk factors. Septicaemia could occur quite early in the postburn days and the mortality due to this organism was quite high. Early excision and grafting with other effective management may result in a better outcome.

Rifampicin as an adjunct to vancomycin therapy in MRSA septicaemia in burns

Rifampicin has been successfully used as an adjunct to vancomycin therapy in several clinical conditions of MRSA infections such as endocarditis, ventriculoperitoneal shunts and septicaemia. However, very little information is available in the literature regarding its use in MRSA septicaemia in burns. The present prospective study was conducted to evaluate the efficacy of rifampicin as an adjunct therapy in burn cases with MRSA septicaemia not responding well to vancomycin. Fourteen out of 36 MRSA septicaemia patients with burns who either did not or only partially responded to therapeutic doses of vancomycin within 5-6 days were treated with rifampicin as an adjunct therapy (600 mg, i.v., o.d) for 5 days during the study period between January 1995 to December 1998. All the patients had burns due to flame and the TBSA varied between 20-90% with a mean of 64%. Eleven patients had deep and three had mixed burns. MRSA septicaemic episodes usually followed 2 3 days of detection of the organism in burn wounds. All the isolates were sensitive to vancomycin with an MIC of < or = 1.0 mg/L and were treated with vancomycin, (500 mg, i.v., 6 hourly). The serum vancomycin levels in all the patients were within the therapeutic range. However, blood cultures still remained positive even after 5-6 days of therapy. Institution of rifampicin, as an adjunct to vancomycin therapy to which the MRSA isolates were susceptible, showed a dramatic clinical response and survival of grafts. Thirteen patients survived and one died who had 70% deep burns and blood cultures revealed a multiresistant Acinetobacter in addition to MRSA. The present study thus confirms the efficacy of clinical use of rifampicin as an adjunct in vancomycin nonresponding cases of MRSA septicaemia in burns.

Bacterial endocarditis following a minor burn injury. Case report and review

A case of bacterial endocarditis in a patient with a total burn area of less than 1% is presented. A high index of suspicion for bacterial endocarditis should exist for any burns patient, regardless of burn size, who becomes unwell and has positive blood cultures.