FormalPara Key Summary Points

Why carry out this study?

Infection is the most common complication among individuals suffering from burns and one of the contributing factors to mortality in patients with burns, more than half of the deaths can be attributed to various infectious complications.

Comprehensive research synopses of the infection spectra and antimicrobial resistance patterns among individuals suffering from burns in China are lacking.

What was learned from this study?

The five most frequently detected pathogens in patients with burn injuries were Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, and Staphylococcus epidermidis.

Both the proportion and resistance of Klebsiella pneumoniae have significantly increased, warranting attention in clinical practice.

Acinetobacter baumannii generally exhibits high resistance to multiple antibiotics (> 50%), which thus highlights the necessity for long-term monitoring efforts.

Introduction

Burn injuries are a global public health concern, with an estimated 120,000 related deaths occurring annually worldwide. The majority of burn-related deaths occur in low- and middle-income countries [1, 2]. China has a high incidence of burn injuries, as evidenced by research indicating that there were 1,079,000 patients with burn injuries in mainland China in 2019, accounting for 12% of the global incidence cases and ranking first worldwide among all countries. With 11,000 deaths, China ranks second globally in terms of burn-related mortality after India, with 26,000 deaths [3]. Burn injuries can result in varying degrees of damage to the skin, which is the body’s largest organ and primary physical barrier against external pathogens [4]. Consequently, both endogenous and exogenous pathogenic microorganisms readily colonize burn wounds, leading to severe infections that endanger patient lives [5]. Infection is the most common complication among individuals suffering from burns and one of the contributing factors to mortality in patients with burns, with approximately 50–75% of deaths attributed to various infectious complications [6, 7]. Hence, effective prevention, control, and treatment of burn infections present urgent challenges for all healthcare institutions.

The pathogens causing infections in patients with burn injuries are predominantly bacteria, with the species composition changing dynamically over time. For instance, although gram-positive bacteria appear earlier than gram-negative bacteria, their duration of persistence is shorter [8]. Research indicates that within the first 5 days of hospitalization, Staphylococcus aureus is the most common pathogen, whereas Pseudomonas aeruginosa becomes predominant after 5 days of admission [9, 10]. Gram-negative bacteria constitute the primary causative agents of infections in patients with burn injuries, accounting for approximately 70% of cases, with notable species including Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae. Gram-positive bacteria account for approximately 30% of cases, with Staphylococcus aureus and Enterococcus spp. being common [11, 12]. The colonization patterns of pathogens that cause burn infections may vary owing to differences in geographical, climatic and environmental factors, hospital management practices and the duration of hospitalization. A study conducted in Morocco identified Acinetobacter baumannii and Pseudomonas aeruginosa as the most common pathogens among patients with burn infection, while studies in China revealed that Staphylococcus aureus and Staphylococcus epidermidis were the most prevalent pathogens isolated from patients with burn injuries [13, 14].

The continuous increase in antibiotic resistance is primarily attributable to the irrational or excessive use of antibiotics. The decreased sensitivity of bacteria to conventional antibiotics has significantly complicated the management of burn infections. The emergence and transmission of multidrug-resistant (MDR) bacteria represent major challenges to global health care systems. The World Health Organization (WHO) estimates that by 2050, an increase in antibiotic resistance could lead to 10 million deaths [15, 16].

As the initial use of antibiotics in patients with burn injuries relies mainly on local microbial epidemiology [17], it is crucial to determine the distribution of pathogens and their resistance characteristics among individuals suffering from burns in China. Clinicians must rationally prescribe antibiotics and formulate strategies to avoid antimicrobial resistance in patients with burn injuries. Although the regional compositions of burn infection pathogens and antibiotic resistance have been studied in China, comprehensive reports on the overall situation with pathogen infections and resistance among individuals suffering from burns in China are lacking [13, 18]. This study aimed to evaluate and summarize the pathogen infection status among individuals suffering from burns in China and provide a synopsis of our current understanding of the infection spectrum and antimicrobial resistance patterns in patients with burn injuries.

Methods

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement [19] and was registered in PROSPERO (CRD42024514386) before the systematic review was performed.

Search Strategy

A comprehensive search was conducted in the PubMed, Web of Science, China Biomedical Literature, China National Knowledge Infrastructure, Wanfang, and Weipu databases (Table S1) using a combination of free text and controlled vocabulary (i.e., MeSH terms). This study focused on analyzing the distribution and antimicrobial resistance characteristics of nosocomial pathogens among individuals suffering from burns over the past decade. Therefore, the search was limited to articles published between 1 January 2010 and 30 November 2023. The search terms included “cross infection,” “nosocomial infection,” “hospital infection,” “wound infection,” “bacteria,” “pathogens,” “burns,” and “China.” The retrieved literature was managed using EndNote (version 20), and duplicates were removed. Relevant conference papers were manually searched in the Army Medical University Library journal database, and all references included in the studies were reviewed.

Selection Criteria

The inclusion criteria for the meta-analysis were as follows: (1) studies on nosocomial infections in patients with burn injuries, (2) sample collection started in 2010 or later, (3) a study population comprising Chinese individuals, and (4) sufficient data available to calculate the proportion or antimicrobial resistance rates of pathogens with corresponding 95% confidence intervals (CIs). The exclusion criteria were as follows: (1) abstracts, reviews, or communications; (2) studies with a total number of bacterial isolates fewer than 200; (3) insufficient information, including incomplete or inaccessible study data; and (4) studies based on data from the National Nosocomial Infection Surveillance System.

Data Extraction and Risk of Bias Assessment

The data were extracted independently by two researchers using a data extraction form. The following data were extracted: author, publication year, study region, hospital level, number of patients with burn injuries, total number of pathogens detected, common pathogens isolated from patients with burn injuries, and antibiotic-resistant strains. Disagreements in the data extracted were resolved through consultation with a third party. For duplicate publications, only studies with the highest quality and the most complete or informative data on pathogen strain detection were included. If the study data could be divided into datasets before and after 2015, they were extracted separately.

A predetermined checklist, adapted from previous case series scales and consisting of ten items was used to assess the quality of the included studies [20]. The checklist included two dimensions (external validity and internal validity) with four and six items, respectively. A score of 1 was assigned if the literature was judged to have a low risk of bias for each item by answering yes or no to the questions. The total score ranged from 0 to 10 points, with higher scores indicating higher quality. A risk of bias summary plot was generated using the R 4.1.3 software, with scores ≤ 5 indicating a high risk of bias, scores 6–7 indicating a moderate risk of bias, and scores ≥ 8 indicating a low risk of bias.

Data Analysis

All the statistical analyses were performed using R 4.1.3. Statistical tests were two-tailed, and P < 0.05 was considered to indicate statistical significance, unless otherwise stated. Formulas from previously published articles were used to calculate the proportions of pathogenic and antibiotic-resistant strains in patients with burn injuries in each study [21]. Freeman–Tukey double arcsine transformation was used to stabilize the variance in proportions [22]. The DerSimonian–Laird random-effects model was used to estimate the pooled proportions of pathogens across studies and their 95% CIs [23]. The Cochrane Q test was used to analyze heterogeneity among studies, with the Q statistic approximately following a χ2 distribution with k −1 (where k is the number of studies), and P < 0.10 indicates significant heterogeneity. The magnitude of heterogeneity was quantitatively assessed by the Higgins I2 value, which ranged from 0% to 100%, with higher values indicating greater heterogeneity. Heterogeneity is typically considered significant if I2 exceeds 50% [24]. Funnel plots were used to assess potential publication bias in the included literature, and Egger’s test was employed to evaluate the asymmetry of funnel plots [25].

Subgroup analyses and univariate meta-regression were performed to explore differences in pathogen proportions and resistance rates between studies. In univariate meta-regression analysis, the dependent variable was the proportion or resistance data of pathogens, while the independent variables included the study time (dummy variable: 2015 or after), hospital level (dummy variable: tertiary), risk of bias (dummy variable: high), region (dummy variable: eastern region), and sample size (dummy variable: < 500 isolates). The restricted maximum likelihood method was used to estimate the variance between studies in the meta-regression analysis, and the proportion of variance explained by any meta-regression model was estimated using the R2 statistic [26].

Results

Literature Overview

A total of 2017 relevant articles were initially identified. After removing duplicates, we screened the titles and abstracts of 1373 articles, resulting in the exclusion of 1154 studies. Further screening of the abstracts and full texts led to the exclusion of an additional 159 articles. Among these, 47 studies had a total number of isolated pathogenic strains fewer than 200, 45 articles were not related to infections in patients with burn injuries, 26 studies lacked sufficient data, 19 studies focused on nonhuman subjects, 10 were case reports, 7 were duplicate publications, and 5 were reviews or abstracts. Ultimately, 60 articles meeting the inclusion criteria were identified (Fig. 1). Among the 60 included studies, 1 had a longer time span. To explore the impact of time on pathogen colonization patterns and antimicrobial sensitivity, this study was divided into two parts according to the time (before and after 2015).

Fig. 1
figure 1

Literature inclusion and exclusion processes

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Study Characteristics and Risk of Bias Assessment

The characteristics of the 60 eligible studies are presented in Table 1. A total of 62,819 pathogen isolates were identified, with the number of isolates per study ranging from 209 to 4624. All studies were conducted between 2010 and 2023 and represented 24 provinces out of 34 in China. Specifically, 17 studies were from the western region, 11 from the central region, and 32 from the eastern region. The results of the risk of bias assessment are depicted in Fig. 2, with detailed information provided in Table S2. Individual studies obtained scores ranging from 5 to 9, with 18 studies classified as having high quality (score ≥ 8).

Table 1 Main characteristics of the included studies
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Fig. 2
figure 2

Results of the risk of bias assessment

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Distribution of Nosocomial Pathogens

In total, 18 pathogens were reported in 10 or more studies (Table 2), and meta-analyses were conducted for these pathogens. They included five gram-positive bacteria, eight gram-negative bacteria, and five fungi. Significant heterogeneity was observed among the studies in the pooled estimates, with Higgins I2 values ranging from 87.2% to 98.2% (Q test P < 0.001). The five pathogens with the highest proportions were Staphylococcus aureus (18.3%, 95% CI 16.3–20.4), Pseudomonas aeruginosa (16.2%, 95% CI 14.2–18.5), Acinetobacter baumannii (13.7%, 95% CI 11.7–15.9%), Klebsiella pneumoniae (7.4%, 95% CI 6.2–8.7%), and Staphylococcus epidermidis (5.9%, 95% CI 4.5–7.4%; Table 2, Fig. 3a). The main type of burn infection was wound infection, with pathogen data from 22 studies all sourced from wounds. Among these, the five most frequently detected pathogens in wound infections were consistent with the results derived from clinical samples of all types. However, their rankings varied slightly, with the respective proportions as follows: Staphylococcus aureus (17.8%, 95% CI 14.4–21.5), Pseudomonas aeruginosa (16.0%, 95% CI 12.6–19.8), Acinetobacter baumannii (11.8%, 95% CI 8.8–15.2), Staphylococcus epidermidis (8.6%, 95% CI 5.7–12.0), and Klebsiella pneumoniae (6.2%, 95% CI 4.3–8.4) (Table 2; Fig. 3b). Egger’s test revealed no evidence of publication bias in the pooled proportions (P > 0.05; Fig. S1).

Table 2 Proportions of pathogens causing nosocomial infections in patients with burn injuries
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Fig. 3
figure 3

Distribution of pathogens causing nosocomial infections in patients with burn injuries. a Meta-analyses using data for all types of clinical samples. b Meta-analyses using data for wounds

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Subgroup analyses and univariate meta-regression were used to examine the sources of heterogeneity for the top five pathogens using several covariates: the study time, hospital level, risk of bias, region, and sample size. Studies conducted after 2015 reported a significantly lower estimated proportion of Pseudomonas aeruginosa (13.5%, 95% CI 10.9–16.3) than those conducted before 2015 (17.9%, 95% CI 15.1–20.9) (R2 = 4.89%, Table 3). In contrast, there was an increasing trend for Klebsiella pneumoniae (R2 = 9.60%, Fig. 4), whose proportion increased from 6.2% (95% CI 5.1–7.4) before 2015 to 9.7% (95% CI 7.0–12.7) after 2015. According to the subgroup analysis at the hospital level, the proportion of Staphylococcus epidermidis was significantly greater in nontertiary hospitals (R2 = 9.24%). In the subgroups based on different sample sources, the proportion of Acinetobacter baumannii in bloodstream infections (25.5%, 95% CI 16.3–35.9) was significantly greater than that in wound infections (11.8%, 95% CI 8.8–15.2). However, the proportion of Staphylococcus epidermidis in wound infections (8.6%, 95% CI 5.7–12.0) was significantly greater than that in the pooled results from multiple sample sources (4.6%, 95% CI 3.3–6.1). Univariate meta-regression analysis revealed significant differences in the proportions of Staphylococcus aureus (R2 = 8.04%), Acinetobacter baumannii (R2 = 9.37%), and Staphylococcus epidermidis (R2 = 25.65%) among the risk of bias subgroups. However, the proportions of pathogens did not differ by region or sample size. Nevertheless, in the subgroup analysis by province, we found that the proportions of Staphylococcus aureus exceeded 30% in three provinces (Fig. 5a), namely, Shaanxi Province at 37.0% (95% CI 29.8–44.6), Liaoning Province at 33.4% (95% CI 25.9–41.4), and Qinghai Province at 30.9% (95% CI 28.1–33.8). Furthermore, the proportions of Pseudomonas aeruginosa exceeded 30% in two provinces (Fig. 5b), namely, Anhui Province at 33.0% (95% CI 29.1–37.0) and Sichuan Province at 32.5% (95% CI 27.3–37.9). The detailed results for each subtype can be found in Tables S3–S7.

Table 3 Pooled proportions of the top five pathogens causing nosocomial infections in patients with burn injuries across time subgroups
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Fig. 4
figure 4

Proportions of Klebsiella pneumoniae in patients with burn injuries across different time subgroups

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Fig. 5
figure 5

Geographical distribution of proportions of a Staphylococcus aureus and b Pseudomonas aeruginosa in patients with burn injuries

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Antimicrobial Resistance

We further analyzed the resistance of the top five pathogens to different antibiotics, conducted meta-analyses of antibiotics reported in ten or more studies, and compared resistance rates before and after 2015 (Tables S8–S12). After 2015, Staphylococcus aureus (Fig. 6a) exhibited significantly reduced resistance to clindamycin (R2 = 18.63%), erythromycin (R2 = 25.98%), gentamycin (R2 = 15.35%), penicillin (R2 = 23.56%), and tetracycline (R2 = 44.26%). The resistance of Pseudomonas aeruginosa to aztreonam significantly decreased (R2 = 16.28%). However, Acinetobacter baumannii showed significantly increased resistance to piperacillin (R2 = 30.67%). With the exception of minocycline and tigecycline, Acinetobacter baumannii exhibited high resistance (> 50%) to the remaining 19 antibiotics. After 2015, Klebsiella pneumoniae (Fig. 6b) showed significantly increased resistance to several antibiotics, including cefepime (R2 = 22.48%), ciprofloxacin (R2 = 24.71%), imipenem (R2 = 34.54%), levofloxacin (R2 = 29.77%), meropenem (R2 = 33.82%), piperacillin-tazobactam (R2 = 16.18%), and trimethoprim-sulfamethoxazole (R2 = 41.74%). There was a significant decrease in the resistance of Staphylococcus epidermidis to ciprofloxacin (R2 = 60.94%) and gentamycin (R2 = 31.07%).

Fig. 6
figure 6

Antibiotic resistance rates for Staphylococcus aureus and Klebsiella pneumoniae in different year subgroups (*P < 0.05, **P < 0.01, and ***P < 0.001)

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Discussion

This systematic review summarized data from 60 studies involving a total of 62,819 strains of pathogens. Among the five most frequently detected pathogens in nosocomial infections among individuals suffering from burns, two were gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), while three were gram-negative bacteria (Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae). The resistance rates of both gram-positive bacteria showed decreasing trends, while the three gram-negative bacteria continued to exhibit relatively high levels of resistance, with Klebsiella pneumoniae showing a trend toward increasing resistance, thereby warranting special attention.

Infection is a common complication of burns, with infected individuals suffering from burns having a three times greater mortality than that of uninfected patients [85]. Studies have shown that pathogens causing nosocomial infections in patients with burn injuries change over time. Gram-positive bacteria tend to appear earlier than gram-negative bacteria, possibly because burn wounds are initially sterile, and gram-positive bacteria remaining in the skin glands or hair follicles quickly colonize the surface of burn wounds. However, over time, endogenous or exogenous gram-negative bacteria from the gastrointestinal or respiratory tract gradually colonize the wound surface and replace gram-positive bacteria [8, 86]. Owing to differences in antibiotic sensitivity among different types of pathogens, understanding the types of pathogens causing nosocomial infections in patients with burn injuries and their resistance patterns is of paramount importance for the early prevention of such infections.

In this study, Staphylococcus aureus was the most common pathogen, with a proportion of 18.3%, which was slightly lower than the prevalence rates reported in Pakistan (24.05%) and Iran (20.2%) but comparable to those reported in India (18.11%) and Turkey (18.5%) [87,88,89,90]. Staphylococcus aureus, with its various surface proteins that facilitate binding to host proteins, such as fibronectin in the extracellular matrix [91, 92], is highly likely to infect wounds, including burns and surgical incisions [93, 94]. In addition, Staphylococcus epidermidis was the second most common gram-positive bacterium causing infections in patients with burn injuries. Although Staphylococcus epidermidis is a member of the normal microbiota of the human skin and actively initiates skin immune responses to maintain skin homeostasis, it becomes pathogenic when the skin is damaged [95]. In this study, the proportion of Staphylococcus epidermidis was 5.9%, which is consistent with findings in South Korea (4.4%) [96]. However, in a study conducted in the eastern region of China, the proportion of Staphylococcus epidermidis (0.75%) was significantly lower [18]. This difference may be owing to different causative factors.

This study conducted a meta-analysis of the antibiotic resistance of Staphylococcus aureus and Staphylococcus epidermidis and revealed an overall decreasing trend in the resistance of both gram-positive bacteria. Staphylococcus aureus showed significantly reduced resistance to tetracycline, gentamycin, and ampicillin, which is consistent with findings at the Beijing Children’s Hospital in China [97]. This phenomenon may be attributed to clone replacement leading to decreased antibiotic resistance. Several studies have demonstrated that community-acquired methicillin-resistant Staphylococcus aureus has rapidly spread to hospitals and become predominant, leading to a decrease in the detection rate of hospital-acquired methicillin-resistant Staphylococcus aureus. Since the resistance of community-associated methicillin-resistant Staphylococcus aureus has not significantly changed under the selection pressure of antibiotics, the overall trend is a decrease in the resistance of Staphylococcus aureus [98,99,100]. Similarly, the resistance of Staphylococcus epidermidis to tetracycline, gentamycin, and clindamycin significantly decreased. Furthermore, this study showed that both Staphylococcus aureus and Staphylococcus epidermidis remained fully sensitive to vancomycin, indicating its effectiveness in treating nosocomial infections caused by these two bacteria. Another reason for the overall decreasing trend in resistance of both gram-positive bacteria may be the National Action Plan to Contain Antimicrobial Resistance (2016–2020); the National Action Plan was issued in 2016 by multiple departments in response to the World Health Organization’s (WHO’s) Global Action Plan on Antimicrobial Resistance [101], and implemented comprehensive governance measures at the national level to address bacterial resistance [102].

Gram-negative bacteria are the most common pathogens causing nosocomial infections in patients with burn injuries. In this study, three of the top five detected bacteria were gram-negative, namely, Pseudomonas aeruginosa (16.2%), Acinetobacter baumannii (13.7%), and Klebsiella pneumoniae (7.4%). Although Pseudomonas aeruginosa ranks second in the detection rate among pathogens causing nosocomial infections in patients with burn injuries, the composition of pathogens causing burn infections may vary because of differences in regional climates and hospital types. Honnegowda et al. conducted a survey at the Manipal Burns Centre in India and reported that Pseudomonas aeruginosa was the most common pathogen (35.3%) in samples from patients with burns [89]. Similarly, Saaiq et al. reported that Pseudomonas aeruginosa had the highest proportion (35.29%) in Pakistan [7]. Acinetobacter baumannii possesses strong adhesion and colonization capabilities, can resist dry and humid environments, and is widely distributed in nature [103]. Owing to its significantly increased isolation, infection, and resistance rates, infection control has become challenging. In this study, the proportion of Acinetobacter baumannii ranked third after Pseudomonas aeruginosa; this finding is consistent with the findings of Gupta et al. at a tertiary hospital in India, where Acinetobacter baumannii was the third most common pathogen (14.83%) causing infections in patients with burn injuries [104]. Owing to differences in hospital management among different regions, the proportion of Acinetobacter baumannii also significantly differed. A study by Bayram et al. in Turkey showed that Acinetobacter baumannii was the most common pathogen (23.6%) isolated from patients with burn infection [105]. Klebsiella pneumoniae has gradually become one of the main causes of nosocomial infections in recent years [106]. Although in a study by Chaudhary et al. carried out at a tertiary hospital in Pakistan [87] Klebsiella pneumoniae ranked the same, the detection rate (15.9%) was significantly greater than that observed in our study (7.2%).

Gram-negative bacteria possess multiple mechanisms of resistance. For example, their double membrane structure confers intrinsic resistance to many antibiotics, while efflux pumps, in conjunction with the double membrane, increase resistance and encode various antibiotic-hydrolysing enzymes [107]. Owing to multiple resistance mechanisms, the resistance rates of gram-negative bacteria have been continuously increasing in recent years, posing a global challenge to the accurate and effective treatment of gram-negative bacterial infections. Therefore, understanding the resistance of gram-negative bacteria causing hospital infections is highly important for guiding the selection of appropriate antibiotics during the process of preventing infection. The results of this study show a decreasing resistance trend of Pseudomonas aeruginosa to certain antibiotics. However, its resistance to some other antibiotics, such as ampicillin, cefazolin, and cefotaxime, remains relatively high, which is consistent with the findings of Chaudhary et al. [87]. Among the antibiotics included in the analysis, Acinetobacter baumannii had high resistance (> 50%) to all antibiotics, except minocycline and tigecycline, with resistance rates exceeding 90% for ampicillin, amikacin, cefazolin, and cefotaxime, which is consistent with multiple previous studies [87, 96, 105]. Notably, this study revealed a significant increase in the resistance of Klebsiella pneumoniae, for example, to trimethoprim-sulfamethoxazole, meropenem, and imipenem, which is consistent with the findings of multiple studies [104, 105, 108]. These results indicate the need for strict management of antibiotic use when treating gram-negative bacterial infections to prevent further increases in antibiotic resistance. The study findings also suggest the need to introduce new antibiotics or other infection control measures in the treatment of gram-negative bacterial burn infections.

Fungi, including Candida albicans (1.6%), Candida tropicalis (0.6%), and Candida glabrata (0.5%), can also cause nosocomial infections in patients with burn injuries. Although fungal infections account for a small proportion of infections, infections caused by fungi in patients with burn injuries have no obvious specificity, unlike bacterial infections, thus making them difficult to distinguish and leading to misdiagnosis and delayed treatment [109, 110]. Some fungi, such as Aspergillus and Zygomycetes, are prone to invading blood vessels and spreading to internal organs after infection, often resulting in a poor prognosis and high mortality [111, 112]. Therefore, careful identification of pathogens causing infections in patients with burn injuries is necessary. Previous studies have shown that Candida albicans is the most common fungus that causes burn infections. However, in recent years, both domestic and foreign studies have shown a significant increase in the proportion of non-Candida albicans fungi, such as Candida tropicalis and Candida glabrata, among the detected fungi [113,114,115]. The reason for this phenomenon may be differences in the detection methods for fungi among different regions or even among countries.

Although there was a decreasing trend in the resistance of gram-positive bacteria observed in this study, we must remain vigilant. Moreover, owing to the persistently high levels of resistance in gram-negative bacteria, it is urgent to find solutions to this problem. The emergence of multidrug-resistant bacteria poses a significant threat to the life and health of patients. Therefore, effective prevention and treatment are crucial for improving patient outcomes [116]. Prior to initiating antibiotic therapy, strict microbial surveillance should be conducted, and efforts should be made to avoid the use of inappropriate medications [117, 118]. Additionally, the microbial composition of burn wounds is dynamic, and regular assessments by physicians are required to identify the primary pathogens and their resistance patterns, thus enabling the formulation of optimal treatment strategies for burn infections.

Despite the strict adherence to the PRISMA guidelines in this study, certain limitations need to be considered. First, considerable heterogeneity among the included studies was observed, and subgroup analyses and meta-regression analysis could not fully explain the sources of heterogeneity. Second, because small-sample studies are prone to chance results, studies with fewer isolated pathogens associated with burn infection were excluded from the analysis, resulting in missing detection data for some provinces. Third, the data used for the meta-analysis were retrieved from public databases, which provide limited clinical information, such as patient injury factors, burn sites, burn areas, and burn depths, making it impossible to analyze potential factors affecting the distribution of pathogens in patients with burn injuries.

Conclusions

The results of this study indicate that, in China, the most common gram-positive bacteria involved in burn infections are Staphylococcus aureus and Staphylococcus epidermidis, while the most common gram-negative bacteria are Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae. Wound infections are the most common type of infections in patients with burn injuries. The common pathogens observed in wound infections of patients with burn injuries were consistent with those from clinical samples of all types, with a slight difference in the ranking, such that the detection rate of Staphylococcus epidermidis was greater than that of Klebsiella pneumoniae. Additionally, we found that the analyzed pathogens exhibited very high levels of resistance to penicillin antibiotics and some cephalosporin antibiotics. Therefore, infections caused by these bacteria may have a high incidence and lead to high mortality, highlighting the critical importance of effective prevention and treatment strategies to improve the prognosis of individuals suffering from burns. There is an urgent need to develop more effective antibiotics to address potential infections in patients with burn injuries. Moreover, effective management of the clinical environment to reduce the quantity of environmental pathogens can effectively lower the incidence of nosocomial infections. Notably, the proportion and resistance of Klebsiella pneumoniae have significantly increased, which warrants attention in clinical practice to prevent infection outbreaks among individuals suffering from burns.