A profile of methicillin resistant Staphylococcus aureus infection in the burn center of the Sultanate of Oman

Consensus on the treatment of second-degree burn wounds (2024 edition)

Second-degree burns are the most common type of burn in clinical practice and hard to manage. Their treatment requires not only a consideration of the different outcomes that may arise from the dressing changes or surgical therapies themselves but also an evaluation of factors such as the burn site, patient age and burn area. Meanwhile, special attention should be given to the fact that there is no unified standard or specification for the diagnosis, classification, surgical procedure, and infection diagnosis and grading of second-degree burn wounds. This not only poses great challenges to the formulation of clinical treatment plans but also significantly affects the consistency of clinical studies. Moreover, currently, there are relatively few guidelines or expert consensus for the management of second-degree burn wounds, and no comprehensive and systematic guidelines or specifications for the treatment of second-degree burns have been formed. Therefore, we developed the Consensus on the Treatment of Second-Degree Burn Wounds (2024 edition), based on evidence-based medicine and expert opinion. This consensus provides specific recommendations on prehospital first aid, nonsurgical treatment, surgical treatment and infection treatment for second-degree burns. The current consensus generated a total of 58 recommendations, aiming to form a standardized clinical treatment plan.

Management and prevention of drug resistant infections in burn patients

Introduction: Despite modern advances, the primary cause of death after burns remains infection and sepsis. A key factor in determining outcomes is colonization with multi-drug resistant (MDR) organisms. Infections secondary to MDR organisms are challenging due to lack of adequate antibiotic treatment, subsequently prolonging hospital stay and increasing risk of adverse outcomes. Areas covered: This review highlights the most frequent organisms colonizing burn wounds as well as the most common MDR bacterial infections. Additionally, we discuss different treatment modalities and MDR infection prevention strategies as their appropriate management would minimize morbidity and mortality in this population. We conducted a search for articles on PubMed, Web of Science, Embase, Cochrane, Scopus and UpToDate with applied search strategies including a combination of: "burns, 'thermal injury,' 'infections,' 'sepsis,' 'drug resistance,' and 'antimicrobials.' Expert opinion: Management and prevention of MDR infections in burns is an ongoing challenge. We highlight the importance of preventative over therapeutic strategies, which are easy to implement and cost-effective. Additionally, targeted, limited use of antimicrobials can be beneficial in burn patients. A promising future area of investigation within this field is post-trauma microbiome profiling. Currently, the best treatment strategy for MDR in burn patients is prevention.

MRSA colonization and acquisition in the burn unit: A systematic review and meta-analysis

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most commonly encountered bacteria in the burn unit. In order to investigate the magnitude of this challenge, we assessed the prevalence of MRSA colonization on admission and the incidence of MRSA acquisition within burn units.

METHODS

We searched PubMed and EMBASE for studies reporting MRSA colonization among patients admitted in burn units.

RESULTS

We identified 16 articles that fulfilled our inclusion criteria and found an overall pooled prevalence of MRSA colonization upon the first 72 h of admission (colonization on admission) to the burn unit of 4.1% (95% CI: 2.7%-5.7%). MRSA acquisition in studies without a decolonization protocol was 21.2% (95% CI: 13.2%-30.5%) with a statistically significant downward trend over the years. Studies that implemented a decolonization protocol yielded a MRSA acquisition incidence rate of 4.5% (95% CI: 0.9%-10.6%). MRSA acquisition was higher among patients that have had inhalation injury (OR 3.96, 95% CI: 2.51-6.23), flame burns (OR 1.85, 95% CI: 1.25-2.73), or ICU admission (OR 3.12, 95% CI: 2.18-4.47).

CONCLUSION

Our study yielded that among burn victims, MRSA colonization prevalence on admission is not negligible and the risk of becoming MRSA colonized during hospitalization is higher when no decolonization protocols are implemented. Flame burns, admission to ICU, and inhalation injury were found to be associated with MRSA acquisition.

Successful control of a methicillin-resistant Staphylococcus aureus outbreak in a burn intensive care unit by addition of universal decolonization with intranasal mupirocin to basic infection prevention measures

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is frequently implicated in health care-associated outbreaks in burn intensive care units, incurring substantial morbidity and mortality to these high-risk patients and excess costs to health care systems.

METHODS

MRSA health care-associated infections (HAIs) were noted before and after the implementation of basic infection prevention measures and the subsequent implementation of universal decolonization with intranasal mupirocin. Pulsed-field gel electrophoresis was used to determine the relatedness of clinical isolates. A case-control study was conducted to characterize the risk factors for MRSA HAIs.

RESULTS

Basic interventions failed to decrease the rate of MRSA HAIs, although compliance with these interventions was high throughout the study. MRSA HAIs decreased from 8.53 HAIs per 1,000 patient days before the implementation of intranasal mupirocin to 3.61 HAIs per 1,000 patient days after the implementation of intranasal mupirocin (P = .033). Pulsed-field gel electrophoresis disclosed 10 unique clones with no large clusters. The case-control study revealed a significant association between MRSA HAIs and lengths of stay, body surface area burned, intubation, pressor requirement, leukocytosis, lactic acidosis, development of pneumonia, MRSA colonization, and death.

CONCLUSIONS

Basic environmental and behavioral interventions fell short of controlling a low-count, sporadic, and multiclonal MRSA outbreak in the burn intensive care unit of a tertiary medical center. However, the added implementation of universal decolonization with intranasal mupirocin was effective. Burn victims with greater disease severity were at higher risk for MRSA HAIs.

Infection in Burns

BACKGROUND

Developments in critical care and surgical approaches to treating burn wounds, together with newer antimicrobial treatments, have significantly reduced the morbidity and mortality rates associated with this injury.

METHODS

Review of the pertinent English-language literature.

RESULTS

Several resistant organisms have emerged as the maleficent cause of invasive infection in burn patients, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, Pseudomonas, Acinetobacter, non-albicans Candida spp., and Aspergillus. Advances in antimicrobial therapies and the release of new classes of antibiotics have certainly added to the armamentarium of therapeutic resources for the clinician.

CONCLUSION

Strict infection control measures, constant wound surveillance with regular sampling of tissues for quantitative culture, and early excision and wound closure remain the principal adjuncts to control of invasive infections in burn patients.

Genotyping of methicillin-resistant Staphylococcus aureus in the Sultan Qaboos University Hospital, Oman reveals the dominance of Panton-Valentine leucocidin-negative ST6-IV/t304 clone

The objective of this study was to determine the prevalence and distribution of methicillin-resistant Staphylococcus aureus (MRSA) genotypes circulating at a tertiary hospital in the Sultanate of Oman. A total of 79 MRSA isolates were obtained from different clinical samples and investigated using antibiogram, pulsed-field gel electrophoresis (PFGE), staphylococcal chromosome cassette mec (SCCmec), Spa typing and multilocus sequence typing (MLST). The isolates were susceptible to linezolid, vancomycin, teicoplanin, tigecycline and mupirocin but were resistant to tetracycline (30.4%), erythromycin (26.6%), clindamycin (24.1%), trimethoprim (19.0%), ciprofloxacin (17.7%), fusidic acid (15.2%) and gentamicin (12.7%). Molecular typing revealed 19 PFGE patterns, 26 Spa types and 21 sequence types. SCCmec-IV (86.0%) was the dominant SCCmec type, followed by SCCmec-V (10.1%). SCCmec-III (2.5%) and SCCmec-II (1.3%) were less common. ST6-IV/t304 (n = 30) and ST1295-IV/t690 (n = 12) were the dominant genotypes followed by ST772-V/t657 (n = 5), ST30-IV/t019/t021 (n = 5), ST22-IV/t852 (n = 4), ST80-IV/t044 (n = 3) and 18 single genotypes that were isolated sporadically. On the basis of SCCmec typing and MLST, 91.2% of the isolates were classified as community-associated MRSA and 8.8% of the isolates (consisting of four ST22-IV/t852, one ST239-III/t632, one ST5-III/t311 and one ST5-II/t003) were classified as healthcare-associated MRSA. The study has revealed the dominance of a Panton–Valentine leucocidin-negative ST6-IV/t304 clone and provided insights into the distribution of antibiotic resistance in MRSA at the tertiary hospital in Oman. It also highlights the importance of surveillance in detecting the emergence of new MRSA clones in a healthcare facility.

Infectious diseases in the Arabian Peninsula and Egypt

Infectious diseases are important causes of morbidity and mortality globally. Epidemiologically, differences in the patterns of infectious diseases and antimicrobial resistance exist across diverse geographical regions. In this review on infectious diseases in the Arabian Peninsula and Egypt, the epidemiology of tuberculosis, malaria and human immunodeficiency virus (HIV) infections will be addressed. The challenges of the hepatitis C epidemic in Egypt and the epidemiology of this infection across the region will be reviewed. In recent years, we have seen dengue endemicity become established, with major outbreaks in parts of the region. Emerging data also indicate that, across the region, there is an increasing burden of antibiotic resistance, with endemicity in healthcare settings and dissemination into the community. New challenges include the emergence of the Alkhurma haemorrhagic fever virus in Saudi Arabia. The annual Hajj pilgrimage in Saudi Arabia serves as a model for the control of infectious disease in mass gatherings. As most of these countries constantly experience a uniquely dynamic population influx in the form of expatriate workers, tourists, or pilgrims, concerted regional and international collaboration to address these public health concerns in a region that lies at the crossroads for the global spread of infectious pathogens is imperative.

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.

A high prevalence of mupirocin and macrolide resistance determinant among Staphylococcus aureus strains isolated from burnt patients

Infections due to Staphylococcus aureus have become increasingly common among burn patients. The antibiotic resistance profile of S. aureus isolates and inducible resistance against clindamycin were investigated in this study. The presence of mecA gene, mupA gene and macrolide resistance genes were detected using PCR and multiplex-PCR. The resistance rate to methicillin, erythromycin and mupirocin were 58.5%, 58% and 40%, respectively. The prevalence of constitutive and inducible resistance among macrolide resistant isolates was 75% and 25%, respectively. Ninety five percent of the isolates were positive for one or more erm genes. The most common genes were ermA (75%), ermC (72%) and ermB (69%), respectively. The ermA gene predominated in the strains with the inducible phenotype, while ermC was more common in the isolates with the constitutive phenotype. The msrA gene was only found in one MRSA isolate with the constitutive phenotype. A total of 27 isolates (25%) carried the mupA gene. All the mupirocin resistant isolates and almost all the erythromycin resistant isolates were also resistant against methicillin which may indicate an outbreak of MRSA isolates with high-level mupirocin and erythromycin resistance in the burn unit assessed.

Epidemiology of burn injuries in the East Mediterranean Region: a systematic review

BACKGROUND

Burn injuries remain one of the leading causes of injury morbidity and mortality in the World Health Organization's East Mediterranean Region. To provide an overview on the epidemiology of burn injuries in this region, a systematic review was undertaken.

METHODS

Medline, Embase and CINAHL were searched for publications on burns in this region published between 01/01/1997 and 16/4/2007. Data were extracted to a standard spreadsheet and synthesised using a narrative synthesis. No attempt has been made to quantitatively synthesise the data due to the large degree of clinical heterogeneity between study populations.

RESULTS

Seventy one studies were included in the review, from 12 countries. Burn injuries were found to be one of the leading causes of injury morbidity and mortality. The reported incidence of burns ranged from 112 to 518 per 100,000 per year. Burn victims were more frequently young and approximately one third of the victims were children aged 0-5 years. Hospital mortality ranged from 5 to 37%, but was commonly above 20%. Intentional self-harm burns particularly involving women were common in some countries of the region and were associated with a very high mortality of up to 79%.

CONCLUSION

Burn injuries remain an important public health issue in the East Mediterranean Region therefore further research is required to investigate the problem and assess the effectiveness of intervention programmes.

Emerging infections in burns

BACKGROUND

Patients who suffer severe burns are at higher risk for local and systemic infections. In recent years, emerging resistant pathogens have forced burn care providers world wide to search for alternative forms of treatment. Multidrug-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter spp., and various fungal strains have been the major contributors to the increase in morbidity and mortality rates. Multi-drug-resistant S. aureus remains the major cause of gram-positive burn wound infections world wide. Treatment strategies include rigorous isolation protocols and new types of antibiotics where necessary.

METHODS

We reviewed 398 severely burned patients (burns >40% total body surface area [TBSA]) admitted to our hospital between 2000 and 2006. Patients who did not contract multi-drug-resistant gram-negative organisms during their hospital course and received our standard antibiotic regimen-vancomycin and piperacillin/tazobactam-served as controls (piperacillin/tazobactam; n = 280). The treatment group consisted of patients who, during their acute hospital stay, developed infections with multi-drug-resistant gram-negative pathogens and were treated with vancomycin and colistin for at least three days (colistin; n = 118).

RESULTS

Gram-negative organisms continue to cause the most severe infections in burn patients. Colistin has re-emerged as a highly effective antibiotic against multiresistant Pseudomonas and Acinetobacter infections of burns. Patients who required colistin therapy had a significantly larger average total and full-thickness burn than patients treated with piperacillin/tazobactam and vancomycin, and the mortality rate was significantly higher in the colistin group (p < 0.05). However, there was no significant difference between the colistin and piperacillin/tazobactam groups in the incidence of neurotoxicity, hepatic toxicity, or nephrotoxicity. The main fungal pathogens in burn patients are Candida spp., Aspergillus spp., and Fusarium spp. A definitive diagnosis is more difficult to obtain than in bacterial infections. Amphotericin B and voriconazole remain the two most important anti-fungal substances in our practice.

CONCLUSIONS

Innovations in fluid management, ventilatory support, surgical care, and antimicrobial therapy have contributed to a significant reduction in morbidity and mortality rates in burn patients. Vancomycin and clindamycin are the two most important reserve antibiotics for methicillin-resistant Staphylococcus aureus infection. Oxazolidinones and streptogramins have showed high effectiveness against gram-positive infections. Colistin has re-emerged as a highly effective antibiotic against multiresistant Pseudomonas and Acinetobacter infections. Current challenges include Candida, Aspergillus, and molds. The development of new agents, prudent and appropriate use of antibiotics, and better infection control protocols are paramount in the ongoing battle against multi-resistant organisms.

Trimethoprim-sulfamethoxazole for methicillin-resistant Staphylococcus aureus: a forgotten alternative?

Methicillin-resistant Staphylococcus aureus (MRSA) is a growing infectious concern, mainly in the context of its rapid adaptation to novel antibiotic options for its treatment and the growing morbidity, mortality, and healthcare costs associated with its emergence. the authors sought to investigate whether an older antibiotic, such as trimethoprim-sulfamethoxazole (SXT), may have a role in treating MRSA-related infections, according to the available literature on the subject. The authors reviewed literature data on: resistance of MRSA to SXT worldwide in recent years, efficacy of SXT for MRSA decolonization or prophylaxis from MRSA infections, and clinical therapeutic efficacy of SXT in treating mild or severe community-acquired or hospital-acquired MRSA infections. Resistance varies worldwide, in general being low in the industrialized world and higher in developing countries. SXT is one of the numerous understudied options for MRSA decolonization and is growingly recognized as potentially effective in preventing MRSA infections in certain settings. Limited data on its therapeutic efficacy are encouraging, at least for mild, community-acquired infections. SXT may represent a cost-effective alternative weapon against MRSA. Its utility against this increasingly threatening pathogen need clarification through further clinical trials.

Surveillance of antibacterial resistance in Staphylococcus aureus isolated in Kuwaiti hospitals

OBJECTIVE

To investigate the prevalence of antibiotic resistance among Staphylococcus aureus isolated in Kuwaiti hospitals.

MATERIALS AND METHODS

S. aureus were isolated and identified following standard microbiological methods. Antibacterial susceptibility test was performed by disk diffusion and the measurement of minimum inhibitory concentration with E-test strips.

RESULTS

A total of 1,846 S. aureus isolates were analyzed from 13 hospitals between 1 March and 30 October 2005. They were isolated from 1,765 (95.6%) inpatients and 81 (4.4%) outpatients. Methicillin resistance was detected in 588 (32.0%) of the isolates. The methicillin-resistant S. aureus (MRSA) consisted of 461 (78%) multiresistant and 127 (22%) nonmultiresistant isolates. The nonmultiresistant MRSA consisted of epidemic MRSA-15 and community-associated MRSA. The community-associated MRSA was detected in all hospitals with MRSA, indicating its establishment in Kuwaiti hospitals. The proportion of isolates resistant to gentamicin, kanamycin, erythromycin, tetracycline, ciprofloxacin, fusidic acid and trimethoprim was higher among MRSA than methicillin-susceptible S. aureus (MSSA) isolates. Twenty-four and 22% of MRSA and MSSA isolates, respectively, expressed reduced susceptibility to vancomycin (minimum inhibitory concentration = 3-4 mg/l).

CONCLUSION

The study revealed the presence of methicillin resistance in 32% of S. aureus isolated in Kuwaiti hospitals and revealed an increase in the number of MRSA and MSSA with reduced susceptibility to vancomycin.

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.

The time-related changes of antimicrobial resistance patterns and predominant bacterial profiles of burn wounds and body flora of burned patients

To examine the bacterial isolates from the burn patients and to compare the antibiograms of the predominant bacteria isolated from 51 patients who were hospitalized at least 3 weeks or more over a period of 7 months, a prospective study was undertaken. Periodic swabs were taken from burn wound, nasal, axillary, inguinal, and umbilical region of the patients on admission and on 7th, 14th, and 21st days of hospitalization. Mean hospital stay was 36.5 days. A total of 1098 microbial isolates were detected during the study period. Coagulase-negative staphylococci (CNS, 63.0%) and Staphylococcus aureus (19.7%) were the most prevalent isolates in admission cultures. During the next weeks, these bacteria were superceded by mainly Pseudomonas aeruginosa. Between admission and 21st day, the rates of methicillin resistance of staphylococci strains increased steadily. There was no vancomycin resistance in any staphylococci strains, although nine of the S. aureus isolates (2.7%) were resistant to teicoplanin. There were no strains producing inducible beta lactamase (IBL) among P. aeruginosa strains. One extended-spectrum beta-lactamase (ESBL)-producing strain was recovered on admission, although strains producing IBL and ESBL were detected at rates of 79.6 and 57.1%, respectively, on the 21st day. The nature of microbial wound colonization, flora changes, and antimicrobial sensitivity profiles should be taken into consideration in using empirical antimicrobial therapy of burned patients.

Bacteriology of burns at the Queen Elizabeth Central Hospital, Blantyre, Malawi

A retrospective study to determine the bacterial profile and antibiotic susceptibility pattern of burn isolates at the Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi was undertaken. While a total of 1825 burn patients were admitted to the hospital over a 6-year period (January 1994 to December 1999) only 317 (17.4%) specimens selected from as many patients were processed. One hundred and seventy (170/53.6%) specimens yielded single while the rest (147/46.4%) had multiple isolates giving a total of 535 bacterial isolates. Of this number, 236 (44.1%) were Gram-negatives and 299 (55.9%), Gram-positives. Among the Gram-negatives, Pseudomonas aeruginosa, Proteus mirabilis, Coliforms/Escherichia coli and Klebsiella pneumoniae were the most common accounting for 94.1% while in the Gram-positive group, staphylococcal and streptococcal spp. predominated (100%). However, the three most common isolates were Staphylococcus aureus (37.6%), P. aeruginosa (22.4%) and beta-haemolytic streptococci (13.6%). While S. aureus and beta-haemolytic streptococci were most susceptible to penicillin (33.3 and 64.4% susceptibility, respectively), gentamycin appeared most effective against P. aeruginosa (53.3%). A general broad-spectrum resistance to panels of antibiotics used in the study was however observed among the bacterial isolates. From these results, S. aureus, P. aeruginosa, streptococcal spp., P. mirabilis, Coliforms and K. pneumoniae representing 96.4% of all isolates were the most common in the Burns Unit.

Comparison of silver sulfadiazine 1%, mupirocin 2%, and fusidic acid 2% for topical antibacterial effect in methicillin-resistant staphylococci-infected, full-skin thickness rat burn wounds

Silver sulfadiazine 1%, mupirocin 2%, and fusidic acid 2% were compared to assess the antibacterial effect of a once-daily application on experimental rat 15% full-skin thickness burn wounds seeded 24 hours earlier with a 10 standard strain of methicillin-resistant staphylococci. The quantitative counts of seeded organism in burn eschar and subjacent muscle were determined at postburn day 7, beside the cultures of blood and lung biopsies. All tested topical agents were equally effective against methicillin-resistant in reducing local burn wound bacterial count and preventing systemic infection.

MRSA-retrospective analysis of an outbreak in the burn centre Aachen

The growing interest in methicillin-resistant Staphylococcus aureus (MRSA) has been caused by its increased appearance in hospital and community populations. In our burn centre, an outbreak of MRSA was noticed during an 8-month period. We were able to isolate MRSA in eight patients. DNA analysis by pulsed-field gel electrophoresis (PFGE) demonstrated the development of five different strains during this period. Only two patients developed an infection caused by MRSA colonisation. The infections were proven by positive blood culture or catheter colonisation. One patient developed a clinical vancomycin-resistant sepsis which was treated successfully with the additional application of Quinupristin/Dalfopristin. THIS ANALYSIS SHOWS THAT: (1) the development of MRSA in a burn unit is often created in a single patient by long-term antibiotic therapy and not a result of cross-infection, (2) manifest MRSA infection seldom occurs even in colonised burn patients, and (3) a clinically vancomycin-resistant MRSA infection in burn patients can be treated sufficiently with Quinupristin/Dalfopristin.