Introduction

Burn injuries are among the most complex forms of trauma, leading to significant morbidity, prolonged disability, and high mortality worldwide.1,2 The World Health Organization (WHO) estimates that approximately 11 million people suffer from burn injuries each year, with around 180,000 deaths, most of which occur in low- and middle-income countries (LMICs).3 In Nepal, official data are limited due to the absence of a national burn registry, but the government suggests about 2100 deaths and 55,000 burn-related injuries annually. Experts believe these figures underestimate the actual burden, as burns account for roughly 5% of all disabilities across age groups in the country.4

Burn injuries can result from exposure to flames, hot liquids, chemicals, electricity, or radiation, with thermal burns being the most common.5,6 Based on the depth and extent of tissue damage, burns are classified as first-degree (superficial), second-degree (partial thickness), third-degree (full thickness), and occasionally, fourth-degree.7 The loss of skin integrity compromises the body’s primary defence against infection, making burn patients highly susceptible to microbial invasions. The wound environment, which is rich in necrotic tissue and lacks blood supply, provides an ideal setting for bacterial colonization and infection.8–11

Infections are a leading complication in burn patients, primarily when invasive medical devices such as catheters and ventilators are used.12 Common pathogens in burn units include Staphylococcus aureus (S. aureus), Acinetobacter baumannii (A. baumannii), and Pseudomonas aeruginosa (P. aeruginosa), which are capable of forming biofilms that protect them from immune responses and antibiotics.13–16 These infections impose a substantial clinical and public health burden, contributing to prolonged hospitalisation, increased treatment cost, and poorer health outcomes, particularly in resource-limited settings.17 They are projected to cause global economic losses of US$1–3 trillion by 2030, potentially pushing up to 28 million people into extreme poverty and increasing medical treatment costs in low-income countries by about 25%, thereby threatening progress toward the Sustainable Development Goals 2030.18

One of the most alarming challenges in burn care is the emergence of antimicrobial resistance (AMR), particularly multidrug-resistant organisms (MDRO).19 Multi-drug resistance (MDR) is typically defined as bacterial resistance to at least one agent in three or more antimicrobial categories. Even more concerning are Extensively Drug-Resistant (XDR) organisms, which are resistant to all but two or fewer antibiotic classes, and Pan-drug Resistant (PDR) organisms, which are resistant to all available antibiotics.20 The overuse and inappropriate selection of broad-spectrum antibiotics in empirical therapy contribute to this growing threat.21,22

Globally, MDR infections are highly prevalent in burn units, especially in intensive care settings. In countries like Nepal, limited access to effective antibiotics, lack of functional antibiotic stewardship programs, and poor infection control practices exacerbate the prevalence of MDR in burn wound infections.11,23,24 Studies conducted in Nepal have identified MDR strains such as P. aeruginosa, Klebsiella pneumoniae (K. pneumoniae), and A. baumannii as predominant in burn wounds.25–27 Treating these infections often necessitates the use of last-resort antibiotics such as colistin and carbapenems, which have serious side effects.28–30

Despite extensive global research on MDR infections in burn patients, there is limited data from South Asia and almost no comprehensive evidence from Nepal, highlighting the need for this study. This study addresses this gap by providing comprehensive, region-specific insights into MDR infections among burn patients and evaluating key risk factors. Unlike previous studies, which have only focused on mortality among burn patients,23,31 this study addresses MDR infections, their prevalence, and associated risk factors. This study lays a foundation for future research and policy adaptations, guiding antimicrobial stewardship programs and improving clinical practices within Nepal’s burn management framework.

Methodology Study Design, Setting and Sample

The study adopted a retrospective, observational, and quantitative design. The study was conducted at the Department of Burns, Plastic and Reconstructive Surgery in Nepal Cleft and Burn Center, a tertiary care hospital specialising in burn treatment located in Kirtipur, Kathmandu, Nepal. All burn patients admitted to the hospital for treatment in 2023 who met the inclusion criteria were included in the study population, and their medical records were reviewed.

Eligibility Criteria Inclusion Criteria

The study included all the burn patients who received treatment at the hospital, regardless of age, gender, or any pre-existing health conditions. It encompassed burn injuries of all causes, such as flame, scald, chemical, electrical, or radiation burns, and of all degrees. Eligible patients had to have undergone culture and sensitivity testing during their hospital stay and have received at least one course of antibiotic treatment. Those who tested positive for MDROs were categorized into the MDR group, while the rest were placed in the non-MDR group.

Exclusion Criteria

The study excluded burn in pregnant women, patients with incomplete or inadequate medical records, those who did not undergo microbiological investigations, or those admitted for less than 24 hours. Additionally, the analysis excluded patients with pre-existing infections unrelated to the burn and those with no signs of new or hospital-acquired infections after the burn.

Sample Size

The sample size depends on the availability of existing medical data in hospital records, making it a feasibility-based sample. A total of 790 burn patients were admitted from January to December 2023. Of these, 255 were excluded due to missing files (n = 6), pregnancy (n = 2), or the absence of culture testing (n = 247). The remaining 535 patients who underwent culture and sensitivity testing were included to assess the prevalence of MDR. Among them, 187 showed no bacterial growth and were excluded, leaving 348 culture-positive patients for the final analysis. These patients were categorized into MDR and non-MDR groups. The findings are interpreted with appropriate caution, considering the feasibility-based sampling and the exclusions applied [Figure 1].

Figure 1 Sample size determination flowchart. Flow diagram illustrating patient selection from 790 admitted burn patients, with exclusions for missing files, pregnancy, or no culture. Of 535 cultured patients, 187 without bacterial growth were excluded, resulting in a final sample of 348 patients.

Data Collection

The data collection for this study took place from March 2024 to June 2024 at the Nepal Cleft and Burn Centre in Kathmandu. Relevant information, including patient demographics, burn injury details, clinical data, antibiotic regimens, duration of therapy, length of hospital stay, and survival outcomes of burn patients, was extracted using a structured data collection tool. In addition, data on culture results, pathogen identification, and Antimicrobial Susceptibility Test (AST) were collected directly from laboratory records. Microbial identification and AST were performed in the hospital laboratory according to Clinical and Laboratory Standards Institute (CLSI) 2020 guidelines using the Kirby-Bauer disk diffusion method, and zones of inhibition were interpreted using CLSI breakpoints. MDR/XDR/PDR classification was done according to standard definitions (MDR: resistance to ≥1 drug in ≥3 antibiotic classes; XDR: resistance to all but ≤2 classes; PDR: resistance to all classes) based on AST records.20 The antibiotics tested in susceptibility assays included commonly used agents representing multiple antimicrobial classes. These included aminoglycosides (amikacin, gentamicin), penicillins (amoxicillin, cloxacillin), and penicillin/β-lactamase inhibitor combinations (amoxicillin–clavulanic acid, piperacillin–tazobactam). Macrolides (erythromycin, azithromycin), cephalosporins (cefazolin, cephalexin, cefoxitin, cefixime, cefotaxime, cefpodoxime, ceftazidime, ceftriaxone, cefepime), and cephalosporin/β-lactamase inhibitor combinations (cefoperazone–sulbactam) Additional antibiotic classes tested were amphenicols (chloramphenicol), fluoroquinolones (ciprofloxacin, levofloxacin, norfloxacin, ofloxacin), lincosamides (clindamycin), sulfonamides (cotrimoxazole), tetracyclines (doxycycline, tetracycline), and glycylcyclines (tigecycline). Carbapenems (imipenem, meropenem), oxazolidinones (linezolid), nitrofurans (nitrofurantoin), polypeptides (colistin, polymyxin B), and glycopeptides (vancomycin, teicoplanin).

Data Management

Data were initially recorded using a structured proforma and subsequently transferred to an Excel spreadsheet. All physical forms were securely stored in a locked facility, and patient confidentiality was safeguarded through anonymization and de-identification procedures. To prevent data loss, regular backups were stored on Google Drive. The dataset was cleaned and coded for consistency and accuracy. All digital files were password-protected to maintain data security.

Data Analysis

The raw data were cleaned and coded before analysis using Microsoft Excel 2016 and SPSS version 26. Descriptive statistics summarised the demographic details of burn patients and MDR prevalence, presenting the data as frequencies and percentages. The normality of the continuous data was assessed using the Shapiro–Wilk test. Since the data were non-normally distributed, non-parametric tests were applied. Categorical variables were analysed using Pearson’s Chi-square test or Fisher’s exact test, while continuous variables were compared using the Wilcoxon-Mann–Whitney U-test between MDR and Non-MDR groups and presented as medians with interquartile ranges. Binary logistic regression (univariate and multivariate) analysis was conducted to identify independent predictors of MDR. Variables with a p-value less than 0.25 in univariate analysis were selected for multivariate analysis to adjust for potential confounders.32,33 Results were reported as odds ratios with 95% confidence intervals (CI), and p-values less than 0.05 were considered statistically significant.

Results Baseline Characteristics of Burn Patients

Among 348 culture-positive burn patients, children and young adults were most commonly affected, with a median age of 30 years [Interquartile Range (IQR):15.00–52.00]. The median TBSA burned was 20.00% (IQR: 12.00–35.00). Flame burns were the most common cause (60.9%), and second-degree burns were the most prevalent (80.7%). A significant proportion of patients required Intensive Care Unit (ICU) care (54.6%) and presented within 3 days of injury (69.5%). Sepsis (13.8%) and respiratory complications (18.4%) were the leading complications. Common comorbidities included hypertension (9.5%) and diabetes (6.6%). Third-generation cephalosporins (44.5%), polymyxins (34.2%), and glycopeptides (26.7%) were the most commonly used antibiotics. The overall mortality rate was 22.1%, while 11.5% of patients went into Discharge on Patient Request (DOPR) and 2.6% left against medical advice [Table 1].

Table 1 Baseline Characteristics of Burn Patients (N=348)

Prevalence of MDR in Burn Patients

The overall prevalence of antimicrobial resistance, including MDR, XDR, and PDR, among culture-tested burn patients was 56.82%. MDR cases accounted for 28.92% (87 females and 68 males), while XDR cases represented 27.48% (78 females and 69 males), and PDR cases were scarce, comprising only 0.37% (1 female and 1 male). Overall resistance was found to be higher among females (31.03%) compared with males (25.79%) [Figure 2].

Figure 2 Prevalence of resistance levels among culture-tested burn patients (N = 535). This bar graph illustrates the distribution of MDR, XDR, and PDR bacterial infections among male and female burn patients. The y-axis represents frequency (%), and the x-axis displays resistance categories.

Factors Associated with MDR Among Burn Patients

Logistic regression analysis identified key risk factors associated with MDR in burn patients. ICU admission was a significant independent predictor, increasing the odds of MDR by threefold [Adjusted Odds Ratio (AOR): 3.047, CI: 1.089–8.528, p = 0.034]. The most notable risk factor was the use of a nasogastric (NG) tube, which was associated with a 12-fold higher risk of MDR [AOR: 11.830, CI: 1.339–104.489, p = 0.026]. Although bloodstream infections and sepsis showed a strong association in the Crude Odds Ratio (COR), this association lost statistical significance after adjusting for confounders. Factors such as burn size (Total Body Surface Area [TBSA] > 20%), comorbidities, and prolonged hospital stays (> 15 days) were not independently associated with MDR, suggesting that ICU care and invasive devices play a more direct role in the development of MDR. Notably, in the unadjusted analysis, delayed presentation (>3 days) appeared to be associated with decreased odds; however, this association lost significance after adjusting for other variables [Table 2].

Table 2 Factors Associated with MDR Among Burn Patients

Common Pathogens Isolated

Table 3 illustrates the distribution of microorganisms isolated in MDR and Non-MDR (NMDR) patients, which emphasizes the higher prevalence of Gram-negative bacterial infections in MDR patients compared to NMDR patients, with P. aeruginosa (31.6%), K. pneumoniae (19.7%), and A. baumannii (18.4%) being the most common isolates. In contrast, NMDR patients had lower infection rates, with P. aeruginosa (11.4%) and Citrobacter koseri (C. koseri) (15.9%) being the most frequently isolated organisms. Among Gram-positive bacteria (GPB), Methicillin-resistant Staphylococcus aereus (MRSA) was found only in MDR patients (15.1%), while Coagulase-negative Staphylococci (CoNS) (16.1%) were more common in MDR cases than NMDR cases (11.4%). Enterococcus faecalis was more prevalent in NMDR cases (9.1%) compared to MDR cases (2.3%).

Table 3 Mostly Cultured Organism in Burn Patients

The overall prevalence of the most common Gram-Negative Bacteria (GNB) isolates among burn patients was found to be P. aeruginosa (29.0%), K. pneumonia (18.1%), C. koseri (17.5%), A. baumannii (16.4%), and Escherichia coli (E. coli) (13.8%). Among GPB, CoNS (15.5%), and MRSA (13.2%) were identified as common isolates in burn patients. Resistance to widely used antibiotics, including gentamicin, amikacin, ceftazidime, ciprofloxacin, amoxicillin, erythromycin, and cephalexin, was widespread in both gram-negative and gram-positive isolates. Despite this, GNB remained highly susceptible to polymyxins. At the same time, gram-positive organisms remained sensitive primarily to linezolid, vancomycin, and tigecycline.

Incidence and Use of Invasive Devices

Table 4 compares the use of invasive devices between MDR and NMDR patients. Catheters were the most frequently used devices, with 76% of MDR patients requiring them compared to 50% of NMDR patients. Nasogastric (NG) tubes were used exclusively in MDR patients (36.5%), followed by CVP lines (20.4%). Romovac drains were used only in MDR patients (2.0%), though in a smaller proportion. Additionally, ventilator use was higher in MDR patients (10.9%) compared to NMDR patients (4.5%).

Table 4 Use of Invasive Devices Among MDR and NMDR Patients

Incidence and Site of Infection

Table 5 highlights the comparison of infection sites between MDR and NMDR patients, which shows that skin infections were the most common in both MDR (89.1%) and NMDR (97.7%) patients. However, bloodstream infections were significantly more frequent in the MDR group (18.8%) compared to NMDR patients (2.3%). Similarly, Urinary tract infections, lung infections, and catheter-related infections were observed in 12.8%, 4.3% and 11.2% of MDR patients, respectively, while none were reported in NMDR cases.

Table 5 Site of Infection in MDR and NMDR Patients

MDRO and Their Site of Infections

Table 6 illustrates the distribution of common organisms isolated in various sites of infection. Gram-negative bacteria were the predominant pathogens across most infection sites, accounting for 100% of urine infections, 98.7% of blood infections, and 71.1% of skin infections. Key GNB included A. baumanii, frequently isolated from blood (32.0%) and lungs (25.0%); P. aeruginosa, common in blood (23.1%), lungs (33.3%), skin (24.5%), and urine (23.8%); and K. pneumoniae, notably found in urine (23.8%) and blood (21.8%). Gram-positive bacteria were primarily found in skin (28.9%) and catheter infections (18.6%), with MRSA being significant in skin infections (13.0%) and CoNS in catheter infections (11.8%).

Table 6 Mostly Cultured MDROs and Their Location in Burn Patients

Discussion

Burn patients are highly vulnerable to infections due to extensive tissue damage, loss of protective skin barrier, and compromised immune defences, which results in the requirement of prompt and specialized medical attention to reduce the risk of complications and death.34 The increasing burden of antimicrobial resistance in such patients poses a significant challenge, particularly in resource-limited settings like Nepal.35 This study evaluated the prevalence of MDR infections among hospitalized burn patients and identified associated risk factors and common resistant organisms.

Our findings are consistent with the local and international literature, which highlights antimicrobial resistance as a critical threat among burn patients. However, in the context of Nepal, data on the prevalence of MDR and its determinants among burn patients are limited.

Sociodemographic Characteristics

Burn injuries were most commonly observed in the young age group, with the highest proportions in children aged 0–10 years (22.7%) and young adults aged 21–30 years (17.5%). Similar age distributions have been reported by Karki et al,36 Elsous et al,37 and Odondi et al,38 highlighting increased vulnerability among younger populations to accidental household burns and the risk among working-age adults due to occupational exposure. The slightly higher proportion of females (53.7%) compared to males (46.3%) aligns with several studies from South Asia that report a female predominance.25,39–42 This could be due to increased engagement of females in household activities, loose clothing (like saris), and domestic violence.1,43 However, other studies, such as those by Burton et al44 and Dhakal,45 reported higher burn rates among males, attributed to occupational and outdoor activities.

Burn Characteristics

Most patients (over 70%) had mild to moderate burns (≤30% TBSA), which is in agreement with previous studies conducted in Nepal.36,45–47 Early intervention and improved safety awareness may have contributed to these lower TBSA values.48 Flame burns were reportedly the most common cause, followed by scalds and electrical burns, while other causes accounted for a smaller proportion. This result is in alignment with the studies conducted by Tripathee et al, Dhakal, and Othman et al and Khongwar et al4,39,45,49,50 where similar predominance of flame burns was reported. This could be due to open flames, unsafe cooking practices, and fire hazards in remote areas.43 Scald injuries, often associated with hot liquids, are more frequent among children and in domestic settings, probably due to their growing phase, restricted mobility, and interest in exploring.48 While less common, electrical burns pose significant risks, especially in occupational environments or while working at home or with office appliances or circuits.51 However, Ramirez-Blanco et al,52 in contradiction to our findings, reported scald burn to be the leading cause of burn. Most patients in the study sustained second-degree burns (80.7%), as also reported by Eser et al and Ringo et al, who similarly observed a predominance of second-degree injuries among burn cases.53,54 The cause of the burn may influence variation in burn depth. For instance, flame and scald injuries, the most common causes observed in our study, are more likely to result in second-degree burns, often necessitating hospitalization.1

Prevalence of MDR in Burn Patients

A substantial burden of antimicrobial resistance was observed in our study, with more than 50% of burn patients infected by multidrug- or extensively drug-resistant organisms.

A globally varied yet elevated MDR rate has been reported in burn settings.55 For instance, Anjum et al56 in Bangladesh reported 85% of P. aeruginosa isolates from burn wounds were MDR, and 12% were XDR without any identified cases of PDR. Similarly, Naz et al57 found that 55% of Proteus species and 53.3% of Providencia species were MDR, with XDR rates of 39.4% and 46.6%, respectively, and no PDR isolates were obtained from burn wound cultures. More than 50% of the MDR or XDR were found across diverse clinical isolates, including burn and wound infections in the studies conducted in Saudi Arabia and Iran (MDR, 95.8%; XDR, 87.5%) and (MDR, 84%; XDR, 10%),58,59 respectively, with only 6% cases of PDR.59 Although this Saudi study showed a higher total resistance burden, the relative proportions (especially MDR ≫ XDR > PDR) differ from our findings, where MDR and XDR were nearly equivalent. A prevalence of over 20% MDR or XDR and a lesser prevalence of PDR as reported in our study, was found in research conducted by Rajbhandari et al60 and Alnour et al61 (MDR MDR GNB 22.3%, XDR 9.41%, PDR 0%) and (MDR, 29.3%; XDR 33.4%; PDR 12.4%) respectively.

These statistics indicate the concerning rise of MDR across the globe, limiting the effective antibiotic treatment among burn patients. The high burden of resistance observed may be attributable to the empirical use of broad-spectrum antibiotics, limited local antibiotic stewardship programs, prolonged hospitalization, invasive procedures, and ineffective infection control practices commonly seen in burn units.62,63

Risk Factors Contributing to MDR

This study identified ICU admission and the use of an NG tube as independent risk factors significantly associated with the development of MDR infections in burn patients. ICU environments harbor higher concentrations of resistant organisms due to frequent use of broad-spectrum antibiotics, high patient turnover, and the necessity of invasive procedures.64 This finding is consistent with previous studies that reported ICU admission as a key determinant of MDR acquisition in critically ill or burn patients.65

Similarly, Prolonged use of NG tubes facilitates microbial colonization and serves as a potential entry route for pathogens, reflecting both the severity of illness and increased exposure to nosocomial flora.66 Although other factors, such as TBSA > 20%, invasive catheters, sepsis, and bloodstream infections, were significant in univariate analysis, they did not retain significance in the multivariate model. This suggests that these factors may have acted as confounders and that sample size variation across subgroups might have limited statistical power for multivariate analysis. Nonetheless, patients with larger TBSA burns and those requiring invasive devices demonstrated a higher, though not statistically significant risk of MDR infection.21,67 These findings underscore the importance of stringent infection prevention practices in burn units. Early wound excision and coverage, meticulous wound care, and adherence to aseptic techniques during device insertion and handling are critical to minimizing the risk of nosocomial infections.68,69

Common MDR Isolates

The study revealed that P. aeruginosa, K. pneumoniae, and A. baumannii, were common isolates among GNB, while CoNS and MRSA were common isolates among GPB in burn units. This distribution mirrors the patterns reported in multiple studies conducted in burn units worldwide, where GNB predominate among MDR pathogens.70–72P. aeruginosa is well-recognized for its intrinsic resistance mechanisms, including efflux pumps, reduced permeability, and the production of β-lactamases such as extended-spectrum β-lactamases (ESBLs) and metallo-β-lactamases, which significantly limit the available treatment options73,74 and often display resistance to multiple antibiotic classes, including aminoglycosides, fluoroquinolones, cephalosporins, and carbapenems.75 Similarly, Upreti et al concluded 80% of E. coli, 80% of P. aeruginosa, and 68.2% of S. aureus in their study were MDR strains.76 Likewise, Van Langeveld et al77 also found P. aeruginosa and S. aureus as the most common GNP and GPB cultured in MDR patients.

A. baumannii is equally concerning due to its environmental persistence and its remarkable genetic adaptability to acquiring resistance to almost all classes of antibiotics.78 Studies have reported MDR A. baumannii rates exceeding 80% in burn units, with high resistance to carbapenems, fluoroquinolones, and aminoglycosides.79 ALfadli et al80 also indicated A. baumannii as the most common isolated organism, followed by K. pneumonia.

Similarly, K. pneumoniae has emerged as a critical MDR pathogen in burn patients, mainly due to ESBL and carbapenem production, including New Delhi Metallo-β-lactamase-1.81 Increased resistance to macrolides, chloramphenicol, quinolones, as well as β-lactam drugs was observed in MDR K. pneumoniae due to mechanisms such as efflux pumps.82

On the other hand, studies conducted in India, Brazil, and Pakistan showed a prevalence of MDR P. aeruginosa of 15.2%, 23.1%, and 19%, respectively, which is lower compared to our findings.83 These variations likely reflect heterogeneity in infection control measures, antibiotic stewardship and usage policies, surveillance capacity, access to newer antimicrobials, and infection prevention infrastructure across LMICs.

Implications for Clinical Practice and Policies

The findings from this study have several important clinical and policy-level implications. The high prevalence of MDR and XDR infections in burn patients underscores the urgent need for robust infection prevention and control measures, including adequate staffing, routine surveillance cultures, effective environmental hygiene, isolation protocols, and the appropriate use of personal protective equipment, especially in critical care settings.

Identifying ICU stays and NG tube use as modifiable risk factors highlights the importance of judicious use of invasive devices and enhanced aseptic practices. Regular reassessment of the need for invasive devices and their timely removal when clinically appropriate can further reduce infection burden.84 Implementing standardized care bundles for invasive devices and conducting ongoing staff training are key components for effective Infection Prevention and Control.85

Diagnostic delays and empirical antibiotic overuse in LMICs contribute to high resistance rates.86 Given these resistance patterns, empirical antibiotic regimens in burn units should be regularly revised and guided by up-to-date local antibiograms to ensure appropriate initial coverage while minimising unnecessary broad-spectrum antibiotics. Overuse of broad-spectrum antibiotics risks amplifying resistance and limiting future treatment options.87 Our findings underscore the need for tailored antimicrobial stewardship programs that cater to resource-limited environments, with a focus on rational antibiotic prescribing, ongoing education for healthcare workers, and regular antimicrobial audits. Policy-level interventions, including enhanced laboratory funding, regulation of over-the-counter antibiotics, and national AMR action plans, are also essential. Burn units in LMICs must be prioritized due to their vulnerability to rapid transmission and colonization by resistant pathogens. Furthermore, adopting a “One Health” approach, which recognises the interconnectedness of human, animal, and environmental health, can enhance the control of antimicrobial resistance.88 However, many medical professionals are still unaware of this approach, reducing its practical impact.89 Raising awareness and training among healthcare professionals about this integrated approach is essential for sustainable stewardship and improved patient outcomes.

Strengths and Limitations of the Study Strengths

This study provides valuable local evidence on the prevalence of MDR, XDR, and PDR infections among burn patients in a low-resource setting. It offers important insights that can support empirical antibiotic selection and guide targeted infection control strategies. By identifying independent risk factors associated with MDR infections, the study presents clinically relevant findings that can inform patient management. It also contributes to the limited body of research on AMR in burn patients, particularly in LMICs, where such data remain scarce. These findings can help shape antimicrobial stewardship efforts within institutions and inform broader infection prevention policies. Overall, the study addresses a significant knowledge gap and supports evidence-based improvements in treatment protocols for burn patients in LMICs.

Limitations

Despite its contribution, this study has some limitations that should be acknowledged. First, the single-center design may limit the applicability of the findings to other settings with different patient populations, microbial patterns, or infection control practices. Second, the retrospective design introduces the possibility of selection bias and limits the ability to infer causality between identified risk factors and clinical outcomes. The associations described should therefore be interpreted with caution. This study recognized positive culture growth as the sole tool to identify infection, which might not be a true representation. The study was also limited by the absence of data on prior antibiotic use and adherence to treatment protocols, both of which could influence resistance patterns. Only phenotypic antimicrobial susceptibility testing was performed; genetic characterisation and molecular typing were not included, which limits insight into specific resistance mechanisms and strain distribution. Additionally, the lack of follow-up beyond hospitalisation limits the assessment of long-term outcomes or recurrence of infections. Finally, reliance on existing hospital records may have introduced issues related to data completeness and accuracy, which could affect the strength of the conclusions.

Conclusion

This study highlights a substantial burden of antibiotic resistance among burn patients, with nearly half of the culture-positive cases MDR, XDR, and PDR organisms indicating an alarming trend, particularly in low-resource settings. Gram-negative bacteria, especially P. aeruginosa, A. baumannii, and K. pneumoniae, were the most commonly isolated MDR pathogens across various infection sites. The identification of modifiable risk factors, such as ICU admission and the use of a nasogastric tube, provides actionable targets for prevention strategies. Strengthening infection control protocols, optimizing antibiotic stewardship, and implementing regular resistance surveillance can significantly mitigate the emergence and spread of these resistant organisms. These findings contribute valuable evidence to guide targeted interventions and policy decisions in burn care and infection management.

Recommendations

To address the growing concern of antibiotic resistance in burn patients, it is recommended that hospitals implement regular surveillance for monitoring of microbial resistance patterns, specifically focusing on MDROs commonly isolated from burn wounds. Local antibiogram data should be regularly updated and used to guide empirical antibiotic therapy. Antimicrobial stewardship programs must be strengthened to ensure the judicious use of antibiotics through education, prescription audits, and multidisciplinary collaboration. Additionally, infection control measures, particularly those related to the use of invasive devices, should be rigorously enforced to minimize the risk of nosocomial infections. Strengthening microbiology laboratory capacity is crucial for ensuring the timely and accurate identification of resistant pathogens, thereby, enabling informed and evidence-based treatment decisions. Additionally, routine burn unit surveillance should be institutionalised to track local resistance trends and assess the effectiveness of infection control interventions over time.

Future research should focus on assessing the impact of prior antibiotic exposure, evaluating targeted treatment protocols, and conducting longitudinal studies to monitor changes in resistance patterns and the long-term outcomes of stewardship efforts in the burn care setting.

Abbreviations

AKI, Acute Kidney Injury; AMR, Antimicrobial Resistance; AOR, Adjusted Odds Ratio; CI, Confidence Interval; CoNS, Coagulase Negative Staphylococci; COPD, Chronic Obstructive Pulmonary Disease; COR, Crude Odds Ratio; CVP, Central Venous Pressure; DOPR, Discharge On Patient Request; ESBLs, Extended Spectrum Beta Lactamases; GNB, Gram Negative Bacteria; GPB, Gram Positive Bacteria; ICU, Intensive Care Unit; IQR, Inter-Quartile Range; IRC, Institutional Research Committee; LAMA, Leave Against Medical Advice; LOS, Length of Stay; LMICs, Low-Middle Income Countries; LPG, Liquefied Petroleum Gas; MDR, Multi-drug Resistant; MDRO, Multi-drug Resistant Organism; MRSA, Methicillin-resistant Staphylococcus aureus; NG, Nasogastric; NMDR, Non- Multi-drug Resistant; OR, Odds Ratio; PDR, Pan-Drug Resistant; PHECT, Public Health Concern Trust; SPSS, Statistical Package for Social Sciences; TBSA, Total Body Surface Area; WHO, World Health Organization; XDR, Extensively-Drug Resistant.

Data Sharing Statement

The datasets generated and/or analyzed during the current study are not publicly available due to institutional policy and patient confidentiality restrictions, but are available from the corresponding author on reasonable request.

Ethical Approval and Informed Consent

The study received ethical clearance from the Institutional Review Committee (IRC) of Public Health Concern Trust, Nepal (phect-NEPAL), under IRC application number 141-2024. As the study was a retrospective review of patient medical records, the ethics committee waived the requirement for informed consent. Patient confidentiality was strictly maintained throughout the study.

Consent for Publication

No identifiable personal data, images, or videos are included in this manuscript. Therefore, consent for publication was not required.

Acknowledgments

The authors are grateful to the Department of Pharmacy, School of Science, Kathmandu University, for providing the opportunity to perform this research. The authors acknowledge the Department of Burns, Plastic, and Reconstructive Surgery at Nepal Cleft and Burn Center, Kirtipur, for their cooperation and assistance during the study.

Author Contributions

All authors made a significant contribution to the work reported, including aspects such as conception, study design, data collection, analysis, interpretation, or overall project execution. Each author was involved in drafting, revising, or critically reviewing the article; gave final approval of the version to be published; agreed on the journal to which the article had been submitted; and agreed to be accountable for all aspects of the work. The specific contributions are as follows: Conceptualization: SM, SS, UA, KKN, SMS, NM, SS. Supervision: SS, UA, KKN. Data collection, analysis, and writing of the original draft: SM, NM. Data analysis and interpretation: SM, SMS. Critical revision with intellectual contribution: SM, SS, UA, KKN, SMS, NM, SS.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The study was conducted without financial support, and no sponsor had any role in the study design, data collection, data analysis, interpretation, manuscript writing, or decision to submit the article for publication.

Disclosure

The authors declare that they have no competing financial or non-financial interests that could have appeared to influence the work reported in this paper.

References

1. Jeschke MG, van Baar ME, Choudhry MA, Chung KK, Gibran NS, Logsetty S. Burn injury. Nat Rev Dis Primers. 2020;6(1). doi:10.1038/s41572-020-0145-5

2. Zhang P, Zou B, Liou YC, Huang C. The pathogenesis and diagnosis of sepsis post burn injury. Burns Trauma. 2021;9:tkaa047. doi:10.1093/burnst/tkaa047

3. World Health Organization. Burns [Internet]. WHO. 2023. Available from: https://www.who.int/news-room/fact-sheets/detail/burns. Accessed November18, 2024.

4. Tripathee S, Basnet SJ. Epidemiology of burn injuries in Nepal: a systemic review. Burns Trauma. 2017;5:10. doi:10.1186/s41038-017-0075-y

5. American Burn Association.Advanced Burn Life Support (ABLS) Provider Manual: 2018 Update. American Burn Association; 2018. https://www.ameriburn.org/. Accessed December19, 2025.

6. Evers LH, Bhavsar D, Mailänder P. The biology of burn injury. Exp Dermatol. 2010;19(9):777–783. doi:10.1111/j.1600-0625.2010.01105.x

7. Bailey ME, Sagiraju HKR, Mashreky SR, Alamgir H. Epidemiology and outcomes of burn injuries at a tertiary burn care center in Bangladesh. Burns. 2019;45(4):957–963. doi:10.1016/j.burns.2018.12.011

8. Agnihotri N, Gupta V, Joshi RM. Aerobic bacterial isolates from burn wound infections and their antibiograms—a five-year study. Burns. 2004;30(3):241–243. doi:10.1016/j.burns.2003.11.010

9. Jauhari S, Pal S, Goyal M, Prakash R, Juyal D. Bacteriological and antimicrobial sensitivity profile of burn wound infections in a tertiary care hospital of Uttarakhand. IJCRR. 2020;12(12):30–36. doi:10.31782/IJCRR.2020.12127

10. Markiewicz-Gospodarek A, Kozioł M, Tobiasz M, Baj J, Radzikowska-Büchner E, Przekora A. Burn wound healing: clinical complications, medical care, treatment, and dressing types: the current state of knowledge for clinical practice. Int J Environ Res Public Health. 2022;19(3):1338. doi:10.3390/ijerph19031338

11. Vinaik R, Barayan D, Shahrokhi S, Jeschke MG. Management and prevention of drug resistant infections in burn patients. Exp Rev Anti-Infective Ther. 2019;17(8):607. doi:10.1080/14787210.2019.1648208

12. Bennett EE, VanBuren J, Holubkov R, Bratton SL. Presence of invasive devices and risks of healthcare-associated infections and sepsis. J Pediatric Intensive Care. 2018;7(4):188. doi:10.1055/s-0038-1656535

13. Ali S, Assafi M. Prevalence and antibiogram of Pseudomonas aeruginosa and Staphylococcus aureus clinical isolates from burns and wounds in Duhok City, Iraq. J Infect Dev Ctries. 2024;18(01):82–92. doi:10.3855/jidc.18193

14. Donlan RM, Costerton JW. Biofilms: survival mechanisms of clinically relevant microorganisms. Clin Microbiol Rev. 2002;15(2):167. doi:10.1128/CMR.15.2.167-193.2002

15. Lunawat A, Sharma R, Kolla V, Patel S. Emerging resistance of higher antimicrobials and growing sensitivity of old antimicrobials against existing infections in burns. Inter Surg J. 2015;2(3):385–391. doi:10.18203/2349-2902.isj20150505

16. Strauß L, Stegger M, Akpaka PE, et al. Origin, evolution, and global transmission of community-acquired Staphylococcus aureus ST8. Proc Natl Acad Sci USA. 2017;114(49):E10596. doi:10.1073/pnas.1702472114

17. Poudel AN, Zhu S, Cooper N, et al. The economic burden of antibiotic resistance: a systematic review and meta-analysis. PLoS One. 2023;18(5):e0285170. doi:10.1371/journal.pone.0285170

18. Government of Nepal. NAP-AMR (2024-2028) English_fktzjw3. 2024. Available from: https://giwmscdnone.gov.np/media/pdf_upload/NAP-AMR(%202024-2028)%20English_fktzjw3.pdf. Accessed November23, 2025.

19. Bassetti M, Merelli M, Temperoni C, Astilean A. New antibiotics for bad bugs: where are we? Ann Clinic Microbiol Antimicrob. 2013;12:22. doi:10.1186/1476-0711-12-22

20. Magiorakos AP, Srinivasan A, Carey RB, et al. Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance. Clin Microbiol Infect. 2012;18(3):268–281. doi:10.1111/j.1469-0691.2011.03570.x

21. Lachiewicz AM, Hauck CG, Weber DJ, Cairns BA, Van Duin D. Bacterial infections after burn injuries: impact of multidrug resistance. Clinl Infect Dis. 2017;65(12):2130–2136. doi:10.1093/cid/cix682

22. Peleg AY, Hooper DC. Hospital-acquired infections due to gram-negative bacteria. New Engl J Med. 2010;362(19):1804. doi:10.1056/NEJMra0904124

23. Roy S, Mukherjee P, Kundu S, Majumder D, Raychaudhuri V, Choudhury L. Microbial infections in burn patients. ACC. 2024;39(2):214–225. doi:10.4266/acc.2023.01571

24. Sleem AS, Melake NA, Eissa NA, Keshk TF. Prevalence of multidrug-resistant bacteria isolated from patients with burn infection. Menoufia Med J. 2015;28(3).

25. Lamichhane A, Nakarmi KK, Dahal P, et al. Bacteriological profile of burn patients and antimicrobial susceptibility pattern of their wound isolates at Nepal cleft and burn center. J Coll Med Sci-Nepal. 2019;15(3):160–166. doi:10.3126/jcmsn.v15i3.24363

26. Maharjan R, Shrestha B, Shrestha S, et al. Detection of Metallo-β-Lactamases and Carbapenemase production Pseudomonas aeruginosa isolates from burn wound infection. TU J Microbiol. 2020;7:67–74. doi:10.3126/tujm.v7i0.33800

27. Yadav SK, Bhujel R, Hamal P, Mishra SK, Sharma S, Sherchand JB. Burden of multidrug-resistant acinetobacter baumannii infection in hospitalized patients in a tertiary care hospital of Nepal. Infect Drug Resist. 2020;13:725–732. doi:10.2147/IDR.S239514

28. Jin J, Zhu J, Zhu Z, et al. Clinical efficacy and nephrotoxicity of intravenous colistin sulfate in the treatment of carbapenem-resistant gram-negative bacterial infections: a retrospective cohort study. Ann translat Med. 2022;10(20):1137. doi:10.21037/atm-22-4959

29. Sharma E, Chen Y, Kelso C, Sivakumar M, Jiang G. Navigating the environmental impacts and analytical methods of last-resort antibiotics: colistin and carbapenems. Soil Environ Health. 2024;2(1):100058. doi:10.1016/j.seh.2024.100058

30. Sheu CC, Chang YT, Lin SY, Chen YH, Hsueh PR. Infections caused by carbapenem-resistant enterobacteriaceae: an update on therapeutic options. Front Microbiol. 2019;10:80. doi:10.3389/fmicb.2019.00080

31. Hu Y, Li D, Xu L, et al. Epidemiology and outcomes of bloodstream infections in severe burn patients: a six-year retrospective study. Antimicrob Resist Infect Control. 2021;10(1):98. doi:10.1186/s13756-021-00969-w

32. Grant SW, Hickey GL, Head SJ. Statistical primer: multivariable regression considerations and pitfalls†. Eur J Cardiothorac Surg. 2019;55(2):179–185. doi:10.1093/ejcts/ezy403

33. Urolithiasis Burden in Somalia: associated Factors and Regional Distri | RRU. Available from: https://www.dovepress.com/urolithiasis-burden-in-somalia-associated-factors-and-regional-distrib-peer-reviewed-fulltext-article-RRU. Accessed June17, 2025.

34. Santucci SG, Gobara S, Santos CR, Fontana C, Levin AS. Infections in a burn intensive care unit: experience of seven years. J Hosp Infect. 2003;53(1):6–13. doi:10.1053/jhin.2002.1340

35. Acharya KP, Subramanya SH, Lopes BS. Combatting antimicrobial resistance in Nepal: the need for precision surveillance programmes and multi-sectoral partnership. JAC Antimicrob Resist. 2019;1(3):dlz066. doi:10.1093/jacamr/dlz066

36. Karki B, Rai SM, Nakarmi KK, et al. Clinical epidemiology of acute burn injuries at Nepal cleft and burn centre, Kathmandu, Nepal. Annals Plastic Surg. 2018;80(3):S95–S97. doi:10.1097/SAP.0000000000001270

37. Elsous A, Ouda M, Mohsen S, et al. Epidemiology and outcomes of hospitalized burn patients in Gaza strip: a descriptive study. Ethiop J Health Sci. 2016;26(1):9–16.

38. Odondi RN, Shitsinzi R, Emarah A. Clinical patterns and early outcomes of burn injuries in patients admitted at the Moi Teaching and Referral Hospital in Eldoret, Western Kenya. Heliyon. 2020;6(3):e03629. doi:10.1016/j.heliyon.2020.e03629

39. Othman N, Babakir-Mina M, Noori CK, Rashid PY. Pseudomonas aeruginosa infection in burn patients in Sulaimaniyah, Iraq: risk factors and antibiotic resistance rates. J Infect Dev Ctries. 2014;8(11):1498–1502. doi:10.3855/jidc.4707

40. Paudel P. Pattern of Burn patients admitted in a Burn Unit of Bir Hospital Kathmandu. Post-Graduate Medical Journal of NAMS. 2010. Available from: https://www.semanticscholar.org/paper/Pattern-of-Burn-patients-admitted-in-a-Burn-Unit-of-Paudel/4496c65db2ee6224681b88ec2b4367858c3c4e45#citing-papers. Accessed February27, 2025.

41. Ronat JB, Kakol J, Khoury MN, et al. Highly drug-resistant pathogens implicated in burn-associated bacteremia in an Iraqi Burn Care Unit. PLoS One. 2014;9(8):e101017. doi:10.1371/journal.pone.0101017

42. Shankar G, Naik VA, Powar R. Epidemiological study of burn patients admitted in a District Hospital of North Karnataka, India. Ind J Burns. 2014;22(1):83. doi:10.4103/0971-653X.147014

43. WHO. Burns. 2023. Available from: https://www.who.int/news-room/fact-sheets/detail/burns. Accessed December19, 2025.

44. Burton KR, Sharma VK, Harrop R, Lindsay R. A population-based study of the epidemiology of acute adult burn injuries in the Calgary Health Region and factors associated with mortality and hospital length of stay from 1995 to 2004. Burns. 2009;35(4):572–579. doi:10.1016/j.burns.2008.10.003

45. Dhakal DA. Epidemiological study of burn injuries at Nepal Cleft and Burn Centre Kathmandu. Post-Graduate Med J NAMS. 2022;22(2):1–5.

46. Kamal M, Butt N, Siddique N, Qaiser A, Perveen S. Frequency of source and total body surface area (TBSA) burn percentage with outcome in burn patients. J Med Physiol Biophys. 2017;38:21.

47. Rai SM, Karki B, Nakarmi K, et al. Retrospective study on early outcome of acute burn injuries treated at Nepal Cleft and Burn Centre of Public Health Concern Trust-Nepal. J Nepal Health Res Counc. 2014;12(28):195–199.

48. Toma A, Voicu D, Popazu C, et al. Severity and clinical outcomes of pediatric burns—A comprehensive analysis of influencing factors. J Personalized Med. 2024;14(8):788. doi:10.3390/jpm14080788

49. Khongwar D, Hajong R, Saikia J, Topno N, Baruah AJ, Komut O. Clinical study of burn patients requiring admission: a single center experience at North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences. J Family Med Prim Care. 2016;5(2):444–448. doi:10.4103/2249-4863.192337

50. Tripathee S, Basnet SJ. Epidemiology and outcome of hospitalized burns patients in tertiary care center in Nepal: two year retrospective study. Burns Open. 2017;1(1):16–19. doi:10.1016/j.burnso.2017.03.001

51. Zemaitis MR, Cindass R, Lopez RA, Huecker MR. Electrical Injuries. In: StatPearls. StatPearls Publishing; 2025 http://www.ncbi.nlm.nih.gov/books/NBK448087/. Accessed June17, 2025.

52. Ramirez-Blanco CE, Ramirez-Rivero CE, Diaz-Martinez LA, Sosa-Avila LM. Infection in burn patients in a referral center in Colombia. Burns. 2017;43(3):642–653. doi:10.1016/j.burns.2016.07.008

53. Eser T, Kavalci C, Aydogan C, Kayipmaz AE. Epidemiological and cost analysis of burn injuries admitted to the emergency department of a tertiary burn center. Springerplus. 2016;5(1):1411. doi:10.1186/s40064-016-3107-3

54. Ringo Y, Chilonga K. Burns at KCMC: epidemiology, presentation, management and treatment outcome. Burns. 2014;40(5):1024–1029. doi:10.1016/j.burns.2013.10.019

55. Elsheikh R, Makram AM. Multidrug-resistant organisms: the silent plight of burn patients. J Burn Care Res. 2024;45(4):877–886. doi:10.1093/jbcr/irae075

56. Anjum H, Arefin MS, Jahan N, et al. Roles of intrinsic and acquired resistance determinants in multidrug-resistant clinical Pseudomonas aeruginosa in Bangladesh. Bangladesh J Med Sci. 2023;22(3):489–507. doi:10.3329/bjms.v22i3.66960

57. Perween N, Prakash SK, Bharara T. Prevalence of multidrug-resistant and extensively drug-resistant proteus, providencia and morganella species in burn wound infection.

58. Safaei HG, Moghim S, Isfahani BN, et al. Distribution of the strains of multidrug-resistant, extensively drug-resistant, and pandrug-resistant pseudomonas aeruginosa isolates from burn patients. Adv Biomed Res. 2017;6:74. doi:10.4103/abr.abr_239_16

59. Almakrami M, Salmen M, Aldashel YA, et al. Prevalence of multidrug-, extensively drug-, and pandrug-resistant bacteria in clinical isolates from King Khaled Hospital, Najran, Saudi Arabia. Discov Med. 2024;1(1):108. doi:10.1007/s44337-024-00094-8

60. Rajbhandari P, Maharjan S, Aryal S, Pradhan P, Prajapati S. Multidrug resistant (MDR) and extensively drug-resistant (XDR) gram negative bacteria at a tertiary care hospital, in Lalitpur, Nepal. J Patan Acad Health Sci. 2024;11(2):16–23. doi:10.3126/jpahs.v11i2.67628

61. Alnour TMS, Elssaig EH, Abuduhier FM, et al. Phenotypic and genotypic characterization of antibiotic resistant gram negative bacteria isolated in Tabuk City, Saudi Arabia. AJMR. 2021;15(8):433–439. doi:10.5897/AJMR2021.9556

62. Cleland H, Tracy LM, Padiglione A, Stewardson AJ. Patterns of multidrug resistant organism acquisition in an adult specialist burns service: a retrospective review. Antimicrob Resist Infect Control. 2022;11:82. doi:10.1186/s13756-022-01123-w