A clinico-microbiological study of diabetic foot ulcers in an Indian tertiary care hospital

Prevalence and predictors of infected diabetic foot ulcers (DFU) and DFU-related osteomyelitis amongst industrial workers wearing occupational safety footwear

Professionals like deep-miners and factory-workers wear specialized safety-shoes to protect against occupational hazards (OF). The risk factors, clinico-microbiologic profile and complications of diabetic foot ulcers (DFU) in these professionals remain unexplored. A cross-sectional observational study was conducted to describe the unique clinico-microbiologic profile of DFU in those wearing occupational-footwear (OF) and find risk factors for DFU related osteomyelitis in them. Of 331 DFU cases seen over 5 years, those wearing OF (n = 107, 68 underground-miners and 39 steel-factory-workers) had high prevalence of forefoot-DFU (81.3%), dorsal-DFU ( 58.9%), recurrent-DFU (31.8%) and of polymicrobial infections (16.8%). Those with osteomyelitis in the OF group ( n = 53) were younger (53.3 vs. 57, p = 0.02), had higher prevalence of peripheral arterial disease (41.5% vs. 24.1%), past-amputation (28.3% vs. 11.1%), higher SINBAD scores, and were also less likely to change occupational-footwear at < = 6-month-interval (22.6% vs. 55.6%) than those without osteomyelitis (p < 0.05 for all). Increasing age, history of past amputation, CRP and reduced frequency of changing the OF were significant positive risk factors for osteomyelitis. OF change at < = 6-month-interval had a protective effect against osteomyelitis (OR : 0.21, C.I 0.07-0.54, p = 0.002) as well as for recurrence (OR : 15, C.I.: 0.04-0.46, p = 0.002) of DFU. Existing national standards for OF manufacturing and regulations regarding their use in India are inadequate and must be made more stringent for professionals with diabetes, especially those at high risk for DFU like the elderly, history of past amputation or those with LOPS. They need detailed foot-measurements for proper fit, should wear OF always at their work-place and change OF frequently for adequate against DFU-related osteomyelitis as also, recurrent DFU.

MALDI - TOF MS for the identification of obligate anaerobes and metronidazole susceptibility of anaerobic Gram negative bacilli

MALDI-TOF MS, though has facilitated rapid and accurate anaerobe identification, the problem of rising metronidazole resistance amongst the members of Bacteroides fragilis group is cause for concern. In this one-year study period,152 anaerobic Gram negative bacilli and 60 Gram positive anaerobes were isolated from 167 samples obtained from clinically suspected anaerobic infections. Bacteroides fragilis accounted for 56 % of the total anaerobic GNB and Peptoniphilus asacchrarolyticus was the most commonly isolated Gram positive cocci. All isolates were identified by the MALDI-TOF MS except one isolate each of Clostridium and Peptostreptococcus. E-test for members of Bacteroides fragilis group, demonstrated 26.8 % metronidazole resistance.

Deciphering Diabetic Foot Wounds: A Comprehensive Review on Classification, Multidrug Resistance, Microbial Insights, Management & Treatment Strategies, and Advanced Diagnostic Tools

Diabetic foot wounds and infections pose a significant and evolving challenge in diabetes care. Diabetic wound healing has become a major global concern for a very long time. Continuous research has been conducted to increase the healing process in diabetic ulcers to the rate of amputation. Wound healing is prolonged in diabetic patients due to various conditions, such as high glucose levels, neuropathy, poor blood circulation, and prolonged inflammation around the limbs, which causes the healing to be delayed compared to normal patients. Understanding the complexity of chronic foot wounds and the management and proper treatment would lead to a decrease in the risk of amputation. The medical team all over the world is constantly researching to lower the risk. This review paper offers a compelling journey through the multifaceted world of diabetic foot wounds and infections. It underscores the urgency of understanding classification, tackling multidrug resistance, and harnessing microbial insights to revolutionize the treatment and management of diabetic foot complications. Furthermore, it unveils state-of-the-art diagnostics, heralding a brighter future in the battle against this debilitating complication of diabetes.

Genetic Characterization of Methicillin-Resistant Staphylococcus aureus Isolated From Diabetic Foot Ulcers in a Tertiary Care Hospital in Mysuru, South India

Background Diabetic foot ulcers (DFUs) are common complications in diabetes patients, often leading to sepsis and leg amputation. Methicillin-resistant Staphylococcus aureus (MRSA) infections in DFUs pose challenges due to methicillin resistance with mecA and mecC genes. This study aims to assess the prevalence of MRSA in clinical isolates from DFUs, analyze the antibiogram of MRSA isolates, and detect the presence of the mecA and mecC genes among MRSA isolates. Methodology The isolated S. aureus colonies were identified and antimicrobial susceptibility was performed using the Vitek-2 Compact system. Methicillin resistance was also confirmed through the disc diffusion method. Confirmed methicillin-resistant isolates were subjected to real-time polymerase chain reaction (RT-PCR) to detect mecA and mecC genes. Results A total of 474 purulent samples from DFUs yielded 541 distinct isolates, comprising 201 gram-positive and 340 gram-negative organisms. Among the gram-positive organisms, Staphylococcus species predominated, with 79 S. aureus isolates, 34 of which were methicillin-resistant. All MRSA isolates (100%) were sensitive to tetracycline, linezolid, teicoplanin, and vancomycin, and 94% were sensitive to cotrimoxazole but least susceptible to ciprofloxacin and levofloxacin. RT-PCR confirmed the presence of mecA genes in all 34 isolates and mecC genes in three isolates. Conclusions The presence of mecA in all 34 MRSA isolates underscores consistent methicillin resistance. The co-occurrence of mecA and mecC in three isolates hints at genetic diversity. Two MRSA isolates positive for mecC were isolated from rural patients involved in farming and animal husbandry, suggesting an occupational risk. The third patient was from a non-rural area, indicating potential alternative transmission pathways warranting further investigation.

Anaerobes in diabetic foot infections: pathophysiology, epidemiology, virulence, and management

SUMMARYDiabetic foot infections (DFI) are a public health problem worldwide. DFI are polymicrobial, biofilm-associated infections involving complex bacterial communities organized in functional equivalent pathogroups, all including anaerobes. Indeed, multiple pathophysiological factors favor the growth of anaerobes in this context. However, the prevalence, role, and contribution of anaerobes in wound evolution remain poorly characterized due to their challenging detection. Studies based on culture reviewed herein showed a weighted average of 17% of patients with anaerobes. Comparatively, the weighted average of patients with anaerobes identified by 16S rRNA gene sequencing was 83.8%. Culture largely underestimated not only the presence but also the diversity of anaerobes compared with cultivation-independent approaches but both methods showed that anaerobic Gram-negative bacilli and Gram-positive cocci were the most commonly identified in DFI. Anaerobes were more present in deeper lesions, and their detection was associated with fever, malodorous lesions, and ulcer depth and duration. More specifically, initial abundance of Peptoniphilus spp. was associated with ulcer-impaired healing, Fusobacterium spp. detection was significantly correlated with the duration of DFI, and the presence of Bacteroides spp. was significantly associated with amputation. Antimicrobial resistance of anaerobes in DFI remains slightly studied and warrants more consideration in the context of increasing resistance of the most frequently identified anaerobes in DFI. The high rate of patients with DFI-involving anaerobes, the increased knowledge on the species identified, their virulence factors, and their potential role in wound evolution support recommendations combining debridement and antibiotic therapy effective on anaerobes in moderate and severe DFI.

A Living Microecological Hydrogel with Microbiota Remodeling and Immune Reinstatement for Diabetic Wound Healing

Dysregulated skin microbiota and compromised immune responses are the major etiological factors for non-healing diabetic wounds. Current antibacterial strategies fail to orchestrate immune responses and indiscriminately eradicate bacteria at the wound site, exacerbating the imbalance of microbiota. Drawing inspiration from the beneficial impacts that probiotics possess on microbiota, a living microecological hydrogel containing Lactobacillus plantarum and fructooligosaccharide (LP/FOS@Gel) is formulated to remodel dysregulated skin microbiota and reinstate compromised immune responses, cultivating a conducive environment for optimal wound healing. LP/FOS@Gel acts as an "evocator," skillfully integrating the skin microecology, promoting the proliferation of Lactobacillus, Ralstonia, Muribaculum, Bacillus, and Allobaculum, while eradicating colonized pathogenic bacteria. Concurrently, LP/FOS@Gel continuously generates lactic acid to elicit a reparative macrophage response and impede the activation of the nuclear factor kappa-B pathway, effectively alleviating inflammation. As an intelligent microecological system, LP/FOS@Gel reinstates the skin's sovereignty during the healing process and effectively orchestrates the harmonious dialogue between the host immune system and microorganisms, thereby fostering the healing of diabetic infectious wounds. These remarkable attributes render LP/FOS@Gel highly advantageous for pragmatic clinical applications.

Surveillance of Enterobacteriaceae from Diabetic Foot Infections in a Tunisian Hospital: Detection of E. coli-ST131-blaCTX-M-15 and K. pneumoniae-ST1-blaNDM-1 Strains

The study determined the prevalence, antimicrobial resistant (AMR) determinants, and genetic characteristics of Escherichia coli and Klebsiella pneumoniae isolates from patients with diabetic foot infection (DFI) in a Tunisian hospital. A total of 26 Escherichia spp. and Klebsiella spp. isolates were recovered and identified by MALDI-TOF-MS. Antimicrobial susceptibility testing, the detection of AMR determinants and Shiga-like toxin genes, phylogenetic grouping, and molecular typing were performed. Twelve E. coli, 10 K. pneumoniae, 3 K. oxytoca, and 1 E. hermanii were isolated. A multidrug-resistant phenotype was detected in 65.4% of the isolates. About 30.8% of isolates were extended-spectrum β-lactamase (ESBL) producers and mainly carried blaCTX-M-15 and blaCTX-M-14 genes. One blaNDM-1-producing K. pneumoniae-ST1 strain was identified. Class 1 integrons were detected in 11 isolates and 5 gene cassette arrangements were noted: dfrA1+aadA1 (n = 1), dfrA12+aadA2 (n = 3), and dfrA17+aadA5 (n = 1). Other non-β-lactam resistance genes detected were as follows (number of isolates): aac(3')-II (3), aac(6')-Ib-cr(8), qnrB (2), qnrS (4), cmlA (2), floR (4), sul1 (11), sul2 (11), and sul3 (2). The phylogroup B1 was the most frequent (41.7%) among E. coli, and two ESBL-producing isolates corresponded to the ST131-B2 lineage. The ESBL- and carbapenemase-producing Enterobacteriaceae in DFIs are described for the first time in Tunisia.

Antibiotic Treatment Practices and Microbial Profile in Diabetic Foot Ulcers: A Retrospective Cohort Study

Aim and objective Diabetic foot ulcers (DFUs) are a frequent complication of diabetes mellitus, impacting more than one in 10 diabetic patients, with roughly half of these ulcers progressing to infection. Existing literature indicates that these infections are predominantly polymicrobial, with gram-positive isolates being the most common. This microbial profile informs the empiric antibiotic strategies employed in first-world countries, often including highly potent nephrotoxic antibiotics. This retrospective cohort study aims to assess the microbial profile and antibiotic treatment practices in patients with infected DFUs at Ochsner LSU Health Shreveport Academic Medical Center in Shreveport, Louisiana, United States. Materials and methods A total of 115 patients diagnosed with infected DFUs were included in the study. Patient records were reviewed to identify bacterial pathogens cultured from foot wounds, antibiotic treatment regimens administered, and the prevalence of acute kidney injury (AKI). Results The study found a predominance of gram-negative isolates (199; 59.4%), facultative anaerobes (246; 73.4%), and polymicrobial infections (67; 78.8%) in infected DFUs. Vancomycin was administered to 95 patients (82.6%), with only a small number subsequently testing positive for methicillin-resistant Staphylococcus aureus (MRSA). Combination therapy with vancomycin and Zosyn was given to 71 patients (61.7%), which increased the potential risk of antibiotic-induced nephrotoxicity. AKI was prevalent, affecting 58 patients (50.4%). Conclusions This study highlights a discrepancy between the microbial profile of infected DFUs and empiric antibiotic treatment practices at Ochsner LSU Health Shreveport Academic Medical Center. The predominance of gram-negative bacteria underscores the need for a polymicrobial, gram-negative-focused empiric treatment approach. Alternative antibiotics with broad-spectrum coverage and minimal nephrotoxicity, such as ceftriaxone, clindamycin, metronidazole, amoxicillin-clavulanate, and linezolid, should be considered. Tailored antibiotic strategies, guided by local microbial profiles and patient-specific factors, are essential to optimize treatment outcomes in this high-risk population.

The Microbial Diversity and Antimicrobial Susceptibility Profile Underlying Diabetic Foot Osteomyelitis: A Retrospective Study Conducted in North Queensland, Australia

Background

Diabetic foot osteomyelitis (DFO) commonly occurs secondary to ulcerations of the skin. Empirical antibiotic agents are a key element of treatment and their use is dependent on local knowledge of the microbial spectrum of diabetic foot infections. This study aimed to retrospectively analyze the local microbiological profile, including bacterial culture/sensitivity results of DFO, and compare findings with literature. This study also aimed to review the concordance of microbiology results with national guidelines for the future treatment of DFO.

Methods

A retrospective review of clinical records was performed on patients who presented to the high-risk foot clinic, Townsville University Hospital, between 2018 and 2022. All patients older than 18 years and diagnosed with DFO were included. Our exclusion criteria included all other foot presentations, including trauma, vasculitis, and neoplasms.

Results

On the basis of the inclusion and exclusion criteria, 124 patients with DFO were selected. Most patients in the cohort were males (70.2%), non-Indigenous (68.5%), aged 50-69 years (55.6%), and with elevated HbA1c levels (>8.6). Chronic kidney disease (39.5%) and ischemic heart disease (41.9%) were common comorbidities. Of the pertinent microbial results, Staphylococcus aureus (~76%) was the most commonly isolated Gram-positive organism. Gram-positive bacteria were significantly increased in the elderly population with DFO (P < .05). All methicillin-resistant S aureus isolates were vancomycin- and cotrimoxazole-sensitive. Pseudomonas aeruginosa was the predominant Gram-negative organism isolated (39.3%). P aeruginosa exhibited low sensitivity to ciprofloxacin.

Conclusion

This study has enhanced our understanding of the various microbial species underlying DFO at our center and may be generalizable.

Level of Evidence

Level IV, retrospective case series.

Molecular characterization of Pseudomonas aeruginosa from diabetic foot infections in Tunisia

Background. Pseudomonas aeruginosa is an invasive organism that frequently causes severe tissue damage in diabetic foot ulcers.Gap statement. The characterisation of P. aeruginosa strains isolated from diabetic foot infections has not been carried out in Tunisia.Purpose. The aim was to determine the prevalence of P. aeruginosa isolated from patients with diabetic foot infections (DFIs) in Tunisia and to characterize their resistance, virulence and molecular typing.Methods. Patients with DFIs admitted to the diabetes department of the International Hospital Centre of Tunisia, from September 2019 to April 2021, were included in this prospective study. P. aeruginosa were obtained from the wound swabs, aspiration and soft tissue biopsies during routine clinical care and were confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing, serotyping, integron and OprD characterization, virulence, biofilm production, pigment quantification, elastase activity and molecular typing were analysed in all recovered P. aeruginosa isolates by phenotypic tests, specific PCRs, sequencing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing.Results. Sixteen P. aeruginosa isolates (16.3 %) were recovered from 98 samples of 78 diabetic patients and were classified into 6 serotypes (O:11 the most frequent), 11 different PFGE patterns and 10 sequence types (three of them new ones). The high-risk clone ST235 was found in two isolates. The highest resistance percentages were observed to netilmicin (69 %) and cefepime (43.8 %). Four multidrug-resistant (MDR) isolates (25 %) were detected, three of them being carbapenem-resistant. The ST235-MDR strain harboured the In51 class 1 integron (intI1 +aadA6+orfD+qacED1-sul1). According to the detection of 14 genes involved in virulence or quorum sensing, 5 virulotypes were observed, including 5 exoU-positive, 9 exoS-positive and 2 exoU/exoS-positive strains. The lasR gene was truncated by ISPpu21 insertion sequence in one isolate, and a deletion of 64 bp in the rhlR gene was detected in the ST235-MDR strain. Low biofilm, pyoverdine and elastase production were detected in all P. aeruginosa; however, the lasR-truncated strain showed a chronic infection phenotype characterized by loss of serotype-specific antigenicity, high production of phenazines and high biofilm formation.Conclusions. Our study demonstrated for the first time the prevalence and the molecular characterization of P. aeruginosa strains from DFIs in Tunisia, showing a high genetic diversity, moderate antimicrobial resistance, but a high number of virulence-related traits, highlighting their pathological importance.

Microbiological profile of diabetic foot infections in China and worldwide: a 20-year systematic review

Introduction

Pathogens causing diabetic foot infections (DFIs) vary by region globally; however, knowledge of the causative organism is essential for effective empirical treatment. We aimed to determine the incidence and antibiotic susceptibility of DFI pathogens worldwide, focusing on Asia and China.

Methods

Through a comprehensive literature search, we identified published studies on organisms isolated from DFI wounds from January 2000 to December 2020.

Results

Based on our inclusion criteria, we analyzed 245 studies that cumulatively reported 38,744 patients and 41,427 isolated microorganisms. DFI pathogens varied according to time and region. Over time, the incidence of Gram-positive and Gram-negative aerobic bacteria have decreased and increased, respectively. America and Asia have the highest (62.74%) and lowest (44.82%) incidence of Gram-negative bacteria, respectively. Africa has the highest incidence (26.90%) of methicillin-resistant Staphylococcus aureus. Asia has the highest incidence (49.36%) of Gram-negative aerobic bacteria with species infection rates as follows: Escherichia coli, 10.77%; Enterobacter spp., 3.95%; and Pseudomonas aeruginosa, 11.08%, with higher local rates in China and Southeast Asia. Linezolid, vancomycin, and teicoplanin were the most active agents against Gram-positive aerobes, while imipenem and cefoperazone-sulbactam were the most active agents against Gram-negative aerobes.

Discussion

This systematic review showed that over 20 years, the pathogens causing DFIs varied considerably over time and region. This data may inform local clinical guidelines on empirical antibiotic therapy for DFI in China and globally. Regular large-scale epidemiological studies are necessary to identify trends in DFI pathogenic bacteria.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023447645.

Association of multidrug-resistant bacteria and clinical outcomes in patients with infected diabetic foot in a Peruvian hospital: A retrospective cohort analysis

OBJECTIVE

To evaluate the association of multidrug-resistant bacteria (MDRB) and adverse clinical outcomes in patients with diabetic foot infection (DFI) in a Peruvian hospital.

MATERIALS AND METHODS

This retrospective cohort study evaluated patients treated in the Diabetic Foot Unit of a General Hospital in Lima, Peru. MDRB was defined by resistance to more than two pharmacological groups across six clinically significant genera. The primary outcome was death due to DFI complications and/or major amputation. Other outcomes included minor amputation, hospitalization, and a hospital stay longer than 14 days. Relative risks were estimated using Poisson regression for all outcomes.

RESULTS

The study included 192 DFI patients with a mean age of 59.9 years; 74% were males. A total of 80.8% exhibited MDRB. The primary outcome had an incidence rate of 23.2% and 5.4% in patients with and without MDRB, respectively (p = 0.01). After adjusting for sex, age, bone involvement, severe infection, ischemia, diabetes duration, and glycosylated hemoglobin, MDRB showed no association with the primary outcome (RR 3.29; 95% CI, 0.77-13.9), but did with hospitalization longer than 14 days (RR 1.43; 95% CI, 1.04-1.98).

CONCLUSIONS

Our study found no association between MDRB and increased mortality and/or major amputation due to DFI complications, but did find a correlation with prolonged hospitalization. The high proportion of MDRB could limit the demonstration of the relationship. It is urgent to apply continuous evaluation of bacterial resistance, implement a rational plan for antibiotic use, and maintain biosafety to confront this threat.

Potential antivirulence activity of sub-inhibitory concentrations of ciprofloxacin against Proteus mirabilis isolates: an in-vitro and in-vivo study

BACKGROUND

Proteus mirabilis is a significant nosocomial pathogen that is frequently associated with a wide range of infections, necessitating heightened attention to mitigate potential health risks. Hence, this study was performed to investigate the impact of sub-minimum inhibitory concentrations (MICs) of ciprofloxacin (CIP) on Proteus mirabilis clinical isolates.

METHODS

The sub-MICs of CIP were selected using the growth curve approach. The untreated and treated isolates with sub-MICs of CIP were assessed for their biofilm development, motilities on agar, and other virulence factors. The cell morphology of untreated and treated isolates with sub-MIC of CIP was explored using electron microscope. Moreover, the expression levels of the virulence genes in isolates were measured using quantitative real-time PCR.

RESULTS

Data revealed that sub-MICs of CIP significantly (p < 0.05), in a concentration-dependent manner, inhibited biofilm formation and other virulence factors in the selected isolates. Electron microscope analysis showed cell enlargement and various abnormalities in the cell wall and membrane integrity.

CONCLUSION

Sub-MICs of CIP exhibited inhibition of virulence and alterations in morphological integrity against P. mirabilis isolates.

Bacteriological analysis and antibiotic resistance in patients with diabetic foot ulcers in Dhaka

The primary objective of this study was to isolate bacteria from diabetic foot ulcers and subsequently assess their antibiotic resistance capabilities. Seventy-five patients diagnosed with diabetic foot ulcers were investigated. A number of these patients (97.33%) had type 2 diabetes, with a significant proportion of them having been diagnosed for 1-5 years (29.33%). Notably, a substantial number of these individuals were on insulin usage (78.66%). Among the patients under examination, 49.33% reported having no use of tobacco products, alcohol, or betel leaf. The ulcers analyzed in this study were classified into grades 1-5 according to the Wagner scale. Wagner grade 2 diabetic foot ulcers had the highest number of culture-positive patients, at 33.33%. Pus samples collected from patients were cultured on selective media, and bacterial identity was confirmed by biochemical tests and polymerase chain reaction. A total of 141 isolates were isolated. Among the isolates, 82.97% gram-negative bacteria and 17.02% gram-positive bacteria were detected. Klebsiella pneumoniae was the most common isolate. Proteus spp., Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were also detected. Approximately 61.33% of the ulcers exhibited were polybacterial. In this study, it was observed that all bacterial isolates, except for Proteus spp., were primarily detected in patients classified under Wagner's grade 2. Moreover, antibiotic susceptibility was also tested on these 141 isolates. Among them, Escherichia coli showed the highest multidrug resistance, 81.81%. Most of the gram-negative bacteria were resistant to ampicillin. All of the gram-negative isolates exhibited high levels of susceptibility to piperacillin-tazobactam, and these levels were Klebsiella pneumoniae (97.56%), Pseudomonas aeruginosa (95.24%), Escherichia coli (81.82%), and Proteus spp. (80%). On the other hand, gram-positive Staphylococcus aureus mostly showed sensitivity towards vancomycin and norfloxacin (79.17%).

Optimizing Antibiotic Treatment for Diabetic Foot Infections: A Study From a Tertiary Public Healthcare Center in Puducherry, South India

BACKGROUND

Diabetic foot infections (DFIs) represent a significant complication of diabetes mellitus, contributing to increased morbidity and mortality. Understanding antibiotic prescribing patterns and microbial susceptibility is crucial for effective management.

OBJECTIVE

This study aimed to assess antibiotic prescribing trends and microbial susceptibility patterns in DFIs in a tertiary care center in Puducherry.

METHODS

A prospective observational study was conducted over two months, involving patients with DFIs attending surgery OPD and admitted inpatient wards. Data on demographics, comorbidities, ulcer characteristics, antibiotic prescriptions, and microbial culture results were collected. Descriptive statistics and appropriate statistical tests were used for analysis.

RESULTS

Of 110 patients included, most were males (80, 72.7%) aged 51-60 years (43, 39.1%). Common risk factors included poor glycemic control (85, 77.3%), barefoot walking (29, 26.4%), and a family history of diabetes (46, 41.8%). Gram-negative organisms (78, 70.9%) predominated, with Escherichia coli (17, 15.5%), Pseudomonas aeruginosa (12, 10.9%), and Staphylococcus aureus (10, 9.1%) being common isolates. Polypharmacy was observed, with (63) 57.3% receiving multiple antibiotics, mainly via the parenteral route (16, 64.5%). Ceftriaxone (31, 28.2%) and cefotaxime (21, 19.1%) were frequently prescribed. Antibiotic resistance varied among isolates.

CONCLUSION

This study underscores the predominance of gram-negative organisms in DFIs and highlights the need for rational antibiotic prescribing. Cephalosporins were commonly used, emphasizing the importance of empirical therapy. Understanding local microbial patterns and susceptibility is crucial for guiding antibiotic selection and optimizing clinical outcomes. In addition, addressing modifiable risk factors is imperative for preventing DFIs and reducing associated complications. This study provides valuable insights for strengthening antimicrobial stewardship programs and improving patient care in diabetic foot management. Furthermore, the present study highlights the importance of essentially deprescribing the prescriptions both from the patient, their primary carer, and the treating physician/surgeon's perspective.

Prevalence of multidrug-resistant bacterial infections in diabetic foot ulcers: A meta-analysis

Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried out a meta-analysis aimed at investigating the prevalence of MDR bacteria isolated from DFUs and analysing the risk factors for MDR bacterial infection in patients with DFUs. The PubMed/Medline, Web of Science, Embase, Cochrane Library, Ovid, Scopus, and ProQuest databases were searched for studies published up to November 2023 on the clinical outcomes of MDR bacteria in DFUs. The main outcome was the prevalence of MDR bacteria in DFUs. A total of 21 studies were included, representing 4885 patients from which 2633 MDR bacterial isolates were obtained. The prevalence of MDR bacteria in DFUs was 50.86% (95% confidence interval (CI): 41.92%-59.78%). The prevalence of MDR gram-positive bacteria (GPB) in DFUs was 19.81% (95% CI: 14.35%-25.91%), and the prevalence of MDR gram-negative bacteria (GNB) in DFUs was 32.84% (95% CI: 26.40%-39.62%). MDR Staphylococcus aureus (12.13% (95% CI: 8.79%-15.91%)) and MDR Enterococcus spp. (3.33% (95% CI: 1.92%-5.07%)) were the main MDR-GPB in DFUs. MDR Escherichia coli, MDR Pseudomonas aeruginosa, MDR Enterobacter spp., MDR Klebsiella pneumoniae, and MDR Proteus mirabilis were the main MDR-GNB in DFUs. The prevalence rates were 6.93% (95% CI: 5.15%-8.95%), 6.01% (95% CI: 4.03%-8.33%), 3.59% (95% CI: 0.42%-9.30%), 3.50% (95% CI: 2.31%-4.91%), and 3.27% (95% CI: 1.74%-5.21%), respectively. The clinical variables of diabetic foot ulcer patients infected with MDR bacteria and non-MDR bacteria in the included studies were analysed. The results showed that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization and previous use of antibacterial drugs were significantly different between the MDR bacterial group and the non-MDR bacterial group. We concluded that there is a high prevalence of MDR bacterial infections in DFUs. The prevalence of MDR-GNB was greater than that of MDR-GPB in DFUs. MDR S. aureus was the main MDR-GPB in DFUs, and MDR E. coli was the main MDR-GNB in DFUs. Our study also indicated that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization, and previous use of antibacterial drugs were associated with MDR bacterial infections in patients with DFUs.

Microbiological and Antimicrobial Pattern of Diabetic Foot Ulcers at a Tertiary Care Center in East China

BACKGROUND

Diabetic foot infections (DFIs) are the most complex and challenging pathological state, characterized by high complexity of management, morbidity, and mortality. Empirical antimicrobial administration is needed before the identification of the causative organisms. Microbiological profile of the diabetic foot patients is the basis of the antibiotic choice for clinicians.

METHODS

76 patients visiting the Diabetic Foot Center of our Hospital for having ulcers with Wagner 3 to 5 were retrospectively surveyed for the bacterium infected. Antimicrobial susceptibility testing (AST) was implemented and the results were interpreted on the basis of the Clinical and Laboratory Standards Institute (CLSI) guidelines.

RESULTS

A total of 92 isolates were obtained, of which 47 strains of gram-negative bacilli (GNB) accounted for 51.1%, 41 strains of gram-positive cocci (GPC) accounted for 44.6%, and 4 strains of fungi accounted for 4.3%. Species of Enterobacteriaceae and Staphylococcus are the two predominant strains. The top 4 most frequently isolated strains were Staphylococcus aureus (22.8%), enterococcus faecalis (9.8%), Pseudomonas aeruginosa (9.8%), Escherichia coli (5.4%). The rate of resistance to methicillin was 33.3% for S. aureus. The rate of extended-spectrum β-lactamases (ESBLs) production among E. coli was 60%. 50% of Klebsiella pneumoniae were resistant to carbapenems. P. aeruginosa showed high sensitivity to commonly used antibiotics. There was one isolate of Acinetobacter spp. resistant to most antimicrobials except tigecycline and aminoglycosides.

CONCLUSION

Enterobacteriaceae and Staphylococcus are the two predominant species. The resistance to antibiotics of S. aureus and P. aeruginosa showed optimistic results. However, the high prevalence of CRKP imposed a challenging issue for clinical physicians.

Metagenomic analysis reveals antibiotic resistance profiles in tissue samples from patients with diabetic foot infections

OBJECTIVES

Treating patients with diabetic foot infection (DFI) is challenging because of high rates of antibiotic resistance. Therefore, to administer a suitable antibiotic treatment, it is necessary to know the antibiotic resistance patterns in DFIs.

METHODS

To explore this question, we selected metagenomic data of 36 tissue samples from patients with DFI in the National Center for Biotechnology Information Sequence Read Archive database.

RESULTS

A total of 229 antibiotic-resistant gene (ARG) subtypes belonging to 20 ARG types were detected. The antibiotic resistome of 229 different genes in the tissue samples of patients with DFI comprised 24 core and 205 accessory resistance genes. Among the core antibiotic resistome, multidrug, tetracycline, macrolide-lincosamide-streptogramin, and beta-lactam resistance genes were the dominant categories. Procrustes analysis indicated that both the microbial community composition and mobile genetic elements (MGEs) were determinants of the ARGs. In the network analysis, 29 species were speculated to be potential hosts of 28 ARGs based on the co-occurrence results. Plasmids and transposons were the most common elements that co-occurred with ARGs.

CONCLUSIONS

Our study provided detailed information about antibiotic resistance patterns in DFI, which has practical implications for suggesting a more specific antibiotic choice.

Diabetic foot ulcer-a systematic review on relevant microbial etiology and antibiotic resistance in Asian countries

BACKGROUND AND AIMS

Diabetic foot ulcer (DFU) is one of the most common but uncontrolled health issues of diabetic patients that needs more therapeutic considerations. This systematic review aims to study the current status of the etiological agents responsible for DFU, their frequency in some of the most occurring Asian countries, and their antibiotic resistance pattern based on available studies.

METHODS

Here, the literature survey was conducted on all the DFU studies with the records of etiological agents and conventional therapeutic treatment published until March 2021 using Medical Literature Analysis and Retrieval System Online (MEDLINE) and Web of Science Core Collection (WoSCC) database.

RESULTS

Overall, in our study, a total of 73 studies representing 12 Asian countries worldwide have been included. We found that the highest number of studies were reported from India (45%) followed by Pakistan (11%), China, Iran and others. 71% of recent studies reported DFU being attributed to poly-microbial infections while the dominant position was significantly secured by Gram- negative bacteria (77%, p = 0.34). Staphylococcus aureus was found to be the most prevalent isolate followed by Pseudomonas and then Escherichia coli (mean value - 22%, 17%, and 15% respectively). Antibiotic sensitivity pattern was determined based on availability in terms of median resistance (MR) and interquartile range (IQR) which showed the growing resistance developed by both Gram-positive and Gram-negative isolates. Gram positive pathogens were still reported as susceptible to vancomycin (MR 0%, IQR 0-22.8%), linezolid (MR 0%, IQR 0-15.53%) and imipenem (MR 11%, IQR 0-23.53%). Carbapenem genera, colistin, and amikacin were the most effective drugs against Gram-negative pathogens.

CONCLUSION

The findings of this study highly recommend searching for alternative and complementary therapeutic regimens instead of prescribing conventional drugs blindly without investigating the progression of the stages of the ulcer, which may help reduce the medical and economic burden of this disease.

Application of antibiotic bone cement in the treatment of infected diabetic foot ulcers in type 2 diabetes

BACKGROUND

In this study, we try to investigate the effect of antibiotic bone cement in patients with infected diabetic foot ulcer (DFU).

METHODS

This is a retrospective study, including fifty-two patients with infected DFU who had undergone treated between June 2019 and May 2021. Patients were divided into Polymethylmethacrylate (PMMA) group and control group. 22 patients in PMMA group received antibiotic bone cement and regular wound debridement, and 30 patients in control group received regular wound debridement. Clinical outcomes include the rate of wound healing, duration of healing, duration of wound preparation, rate of amputation, and frequency of debridement procedures.

RESULTS

In PMMA group, twenty-two patients (100%) had complete wound healing. In control group, twenty-eight patients (93.3%) had wound healing. Compared with control group, PMMA group had fewer frequencies of debridement procedures and shorter duration of wound healing (35.32 ± 3.77 days vs 44.37 ± 7.44 days, P < 0.001). PMMA group had five minor amputation, while control group had eight minor amputation and two major amputation. Regarding the rate of limb salvage, there was no limb lose in PMMA group and two limb losses in control group.

CONCLUSION

The application of antibiotic bone cement is an effective solution for infected DFU treatment. It can effectively decreased the frequency of debridement procedures and shorten the healing duration in patients with infected DFU.

Distribution of microbes and antimicrobial susceptibility in patients with diabetic foot infections in South China

BACKGROUND

To investigate the distribution of microbes and drug susceptibility in patients with diabetic foot infections (DFI) and provide guidance for clinical empirical treatment and the rational selection of antibacterial drugs.

METHODS

Retrospective analysis of the pathogenic bacterium distribution and antimicrobial susceptibility isolated from 581 DFI patients with different Wagner grades.

RESULTS

The 534 positive samples included 473 cases (88.58%)) of monomicrobial infections and 61 cases (11.42%) of polymicrobial infections before antibiotic therapy. A total of 656 strains were cultivated, including 387 (58.99%) strains of gram-positive organisms (GPOs), 235 (35.82%) gram-negative bacilli (GNB), and 21 (3.20%) fungal strains. Polymicrobial infections mainly occurred in patients with Wagner grade 3-4 ulcers. GPOs were predominant in Wagner grades 1-3 (grade 1: 96.67%, grade 2: 76.52%, grade 3 62.81%), and the most common was Staphylococcus aureus (grade 1: 31.66%, grade 2: 33.04%, grade 3 35.53%). GNB were predominant in grades 4-5 (grade 4: 51.46%, grade 5:60%), and the most common GNB in Wagner grades 4-5 was Proteus (grade 4:27.88%, grade 5: 42.86%), while the most common GPO was Enterococcus (grade 4:34.48%, grade 5:25.00%). Staphylococcus (including MRSA) and Enterococcus were still highly sensitive to vancomycin, linezolid, and tigecycline. Most GNB were still highly sensitive to meropenem, tigecycline, ertapenem, and amikacin. Proteus was most sensitive to amikacin (97.14%), followed by meropenem (92%) and ertapenem (80%).

CONCLUSION

The distribution of microbes and antimicrobial susceptibility in DFI patients varied with different Wagner grades. The most appropriate antimicrobial therapy should be selected based on the pathogen culture and antimicrobial susceptibility.

Diabetic Foot Infections: Bacterial Isolates From the Centers and Hospitals of Latin American Countries

Diabetic foot infections (DFIs) are one of the most important reasons for lower limb amputations. An adequate approach to the management of DFI implies control of infection using strategies of tissue debridement and empirical antibiotic treatment based on local microbiology. The aim of this study was to determine the bacterial isolates profile and antibiotic susceptibility patterns in samples from DFI from Latin American centers, on the premise that microbiology of this region differs from that of other continents and influences antimicrobial election. Three hundred and eighty-two samples from soft tissue and bone were studied from 17 centers of 4 countries. Three hundred and seven (80.4%; 95% confidence interval = 75.9-84.2) were positive. Gram negatives (GN) were isolated in 43.8% of all samples, not only in severe but also in mild infections, 51% in bone samples, more frequently in presence of ischemia (47% vs 38%; P = .07) and in wounds with longer duration of the lesion (30-20 days; P < .01). Staphylococcus aureus was the most frequent single germ (19.9%). Gram positives were isolated more frequently in patients without ischemia (53% vs 40%; P = .01). Enterococcus faecalis was the most frequent germ in bone samples (16.8%). Ciprofloxacin and trimethoprim-sulfamethoxazole were the oral antimicrobials most effective against GN. Trimethoprim-sulfamethoxazole and rifampicin were the oral antimicrobials most effective against Staphylococcus. Because of GN high antibiotic resistance patterns, patients treated in an ambulatory setting have to be controlled early after starting empiric treatment to assess response to therapy and hospitalize for parenteral antibiotics if oral treatment fails.

A comparison of rectal and oral cultivable microbiota in wild and captive black lion tamarins (Leontopithecus chrysopygus, Mikan 1823)

The black lion tamarin (Leontopithecus chrysopygus) is an endangered primate species, restricted to the Atlantic Forest fragments of São Paulo state, Brazil, with an estimated wild population of ~1600 individuals. Integrative studies between zoo (ex situ) and wild (in situ) animals are crucial to modern conservation programs. They can demonstrate a substantial impact with the One Health concept, an interdisciplinary research frontier regarding the relations between human, animal, and environmental health. Studies of wild populations of Leontopithecus spp. are scarce and should be encouraged to provide baseline information to develop preventive and curative medicine in zoos and other conservation programs. Studying these animals in the wild can offer important reference parameters for the species. Comparing bacterial communities between in situ and ex situ populations can help us understand both conditions and the dynamics of potentially pathogenic microorganisms. To increase our understanding of resident microorganisms among these groups, we collected oral and rectal samples from captive (zoo) and wild black lion tamarins. We employed a culture method for the identification of aerobic bacteria. Thirty-three specimens were sampled (24 zoo and 8 wild animals) and 18 bacterial genera were identified. We found primarily Gram-positive bacteria in wild animals, whereas in zoo animals, Gram-negative bacteria were dominant. Some of the bacterial species we identified are potentially pathogenic, whereas several others are being reported here for the first time in this host species. Our results reinforce the importance of integrative studies for the future management and conservation of this endangered primate species.

Aerobic bacteria isolated from diabetic foot ulcers of Egyptian patients: types, antibiotic susceptibility pattern and risk factors associated with multidrug-resistant organisms

INTRODUCTION

Diabetic foot infection (DFI) is one of the common diabetic complications. Pathogens causing DFI and their antibiotic susceptibility vary with location. Therefore, empirical antibiotic therapy should be based on the pathogens that are most likely to be present. Aim: To identify the frequent aerobic bacteria causing DFI with detection of their antibiotic susceptibility to help clinicians in our community choose the best empirical antibiotic for DFI.

METHODS

Swabs were collected from 104 diabetic foot ulcers (DFUs). Aerobic bacterial cultures were done followed by bacterial identification and antibiotic susceptibility testing on VITEK® 2 system. Extended-spectrum beta-lacatamase (ESBL) detection was performed phenotypically and confirmed by multiplex-PCR for bla _CTX-M, bla _TEM, and bla _SHV genes.

RESULTS

Aerobic bacterial infection was detected in 82/104 (78.8%) of the DFUs. Gram-negative bacilli (GNB) were isolated more frequently (56.1%) than Gram-positive cocci (GPC) (43.9%). The most common single-isolated bacteria were K. pneumoniae (26.8%), S. aureus and coagulase negative staphylococci (22% for each). The only significant independent predictors of DFI with GNB or GPC were long DM duration and frequent hospitalizations, respectively. The most active antibiotics were amikacin, tigecycline and meropenem for GNB, and linezolid and vancomycin for staphylococci. Multidrug-resistance prevalence was 95.1%. ESBL was detected in 52.6% of Enterobacteriaceae; the bla _CTX-M gene was the most common (90%), followed by bla _TEM (65%) and bla _SHV (35%). Peripheral neuropathy was the single independent predictor for DFI with ESBL producers (adjusted OR=15.5).

CONCLUSIONS

There is a notable local pattern of DFI bacteriology in our community. Our findings could be valuable in developing the future empirical treatment guidelines for DFIs.

Detecting bacterial infections in wounds: a review of biosensors and wearable sensors in comparison with conventional laboratory methods

Review on laboratory-based methods and biosensors and wearable sensors for detecting wound infection by aerobic and anaerobic bacteria.

Role of an acidic environment in the treatment of diabetic foot infections: A review

Management of diabetic foot ulcers is the biggest challenge to the clinician, as conventional antibiotic therapies and local wound care have their own limitations. They are not effective for control of infections and promotion of healing because of cytotoxic effects. In view of cytotoxicity of routinely used topical antiseptic agents, this article focuses on the search of an ideal topical antiseptic agent that is safe and effective in controlling infectious agents and also in promoting the healing process. This review focuses on the use of various acids such as citric, acetic, hyaluronic, and hypochlorous acids as topical agents in diabetic foot infections. This article also focuses on the different roles of acids in the treatment of diabetic foot infections.

Culturomics Approach to Identify Diabetic Foot Infection Bacteria

The main goal of the study was to evaluate the usefulness of the culturomics approach in the reflection of diabetic foot infections (DFIs) microbial compositions in Poland. Superficial swab samples of 16 diabetic foot infection patients (Provincial Polyclinical Hospital in Toruń, Poland) were subjected to culturing using 10 different types of media followed by the identification via the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and Biotyper platform. Identified 204 bacterial isolates representing 18 different species—mostly Enterococcus faecalis (63%) and Staphylococcus aureus (44%). Most of the infections (81%) demonstrated a polymicrobial character. Great differences in the species coverage, the number of isolated Gram-positive and Gram-negative bacteria, and the efficiency of the microbial composition reflection between the investigated media were revealed. The use of commonly recommended blood agar allowed to reveal only 53% of the entire microbial composition of the diabetic foot infection samples, which considerably improved when the chromagar orientation and vancomycin-resistant enterococi agar were applied. In general, efficiency increased in the following order: selective < universal < enriched < differential media. Performed analysis also revealed the impact of the culture media composition on the molecular profiles of some bacterial species, such as Corynebacterium striatum, Proteus mirabilis or Morganella morganii that contributed to the differences in the identification quality. Our results indicated that the culturomics approach can significantly improve the accuracy of the reflection of the diabetic foot infections microbial compositions as long as an appropriate media set is selected. The chromagar orientation and vancomycin-resistant enterococi agar media which were used for the first time to study diabetic foot infection microbial profiles demonstrate the highest utility in the culturomics approach and should be included in further studies directed to find a faster and more reliable diabetic foot infection diagnostic tool.

Multidrug-resistant Bacterial Profile and Patterns for Wound Infections in Nongovernmental Hospitals of Jordan

Globally, multidrug-resistant bacteria affects wound infections, both hospital-acquired infections and community-acquired infections. The main isolates cultured from 607 subjects with wound infections were methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter spp. [multidrug resistant (MDR)]. Gram-negative bacteria caused most of the infections (67%) compared with gram-positive bacteria. Diabetic patients tend to have wound infections with mixed causative agents compared with non-diabetic patients.

Methicillin-Resistant Staphylococcus aureus (MRSA) Infection of Diabetic Foot Ulcers at a Tertiary Care Hospital in Accra, Ghana

Aim: This study investigated the spectrum of bacteria infecting the ulcers of individuals with diabetes at the Korle Bu Teaching Hospital in Accra, Ghana, focusing on Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA), with respect to their prevalence, factors predisposing to their infection of the ulcers, and antimicrobial resistance patterns. Methodology: This cross-sectional study was conducted at The Ulcer Clinic, Department of Surgery, Korle Bu Teaching Hospital, involving 100 diabetic foot ulcer patients. The ulcer of each study participant was swabbed and cultured bacteriologically, following standard procedures. Antimicrobial susceptibility testing was done for all S. aureus isolated, using the Kirby-Bauer method. Results: In total, 96% of the participants had their ulcers infected—32.3% (n = 31) of these had their ulcers infected with one bacterium, 47.9% (n = 46) with two bacteria, 18.8% (n = 18) with three bacteria, and 1.0% (n = 1) with four bacteria. The prevalence of S. aureus and MRSA were 19% and 6%, respectively. The distribution of the other bacteria was as follows: coagulase-negative Staphylococci (CoNS) (54%), Escherichia coli (24%), Pseudomonas spp. (19%), Citrobacter koseri and Morganella morgana (12% each), Klebsiella oxytoca (11%), Proteus vulgaris (8%), Enterococcus spp. (6%), Klebsiella pneumoniae (5%), Proteus mirabilis and Enterobacter spp. (4%), Klebsiella spp. (2%), and Streptococcus spp. (1%). The resistance rates of S. aureus decreased across penicillin (100%, n = 19), tetracycline (47.4%, n = 9), cotrimoxazole (42.1%, n = 8), cefoxitin (31.6%, n = 6), erythromycin and clindamycin (26.3% each, n = 5), norfloxacin and gentamicin (15.8% each, n = 3), rifampicin (10.5%, n = 2), linezolid (5.3%, n = 1), and fusidic acid (0.0%, n = 0). The proportion of multidrug resistance was 47.4% (n = 9). Except for foot ulcer infection with coagulase-negative Staphylococci, which was protective of S. aureus infection of the ulcers (OR = 0.029, p = 0.001, 95% CI = 0.004–0.231), no predictor of S. aureus, MRSA, or polymicrobial ulcer infection was identified. Conclusions: The prevalence of S. aureus and MRSA infection of the diabetic foot ulcers were high, but lower than those of the predominant infector, coagulase-negative Staphylococci and the next highest infecting agent, E. coli. Diabetic foot ulcers’ infection with coagulase-negative Staphylococci protected against their infection with S. aureus. The prevalence of multidrug resistance was high, highlighting the need to further intensify antimicrobial stewardship programmes.

Spectrum of Bacterial Infections Associated with Diabetic Ulcer Patients

Diabetic ulceration is a multi-factorial problem which is responsible for considerable morbidity threatening the health care system. By knowing the clinical profile and bio-burden on diabetic ulcer, it is highly beneficial for health treatment. The purpose of the present study was to evaluate the diversity of major bacterial etiology in diabetic ulcer patients. The different samples like pus, swab, and infected tissues were collected from diabetic ulcer patients aseptically and samples were transported through cold chain to the laboratory. The samples were cultured in nutrient agar, mannitol salt agar, macConkey agar and blood agar. Suspected colonies were biochemically confirmed for the isolation of Staphylococcus aureus, Pseudomonas aeruginosa, E.coli and Klebsiella spp. In total 150 diabetic ulcer patients suffering from diabetic foot ulcers, gangrene, burn cases and accidental ulcer cases were analyzed. However, most of the patients developed mono-microbial infection; S.aureus was the most prevalent microbe in diabetic ulcer cases, which were positive for nucA gene.

Analysis of the microbiota in the diabetic foot ulcers: Is research standardization required?

Background: Complications of infected wounds in patients with diabetic foot ulcer (DFU) are one of the greatest challenges in modern medicine. Analysis of the microbiological profile of infected ulcers may significantly improve treatment results. The aim of the study was to determine the profile of pathogens isolated in patients with DFU and to compare the results of other centers. Materials and Methods: A retrospective study was carried out on 137 patients with DFU hospitalized at the Department of Diabetology and Internal Diseases, Medical University of Warsaw in 2011-2014. The analysis included the results of 200 microbiological cultures tested for fungi, aerobic and anaerobic bacteria. Statistical analysis was used to test differences in HbA1c values in relation to the strain of the most commonly cultured bacteria and the relationship between glycemic control and most frequently isolated pathogens. Results: Seventy-nine bacterial species were isolated in 183 positive cultures. Gram-negative bacteria predominated with the highest percentage of representatives of Enterobacterales. The most often isolated bacteria were Serratia marcescens, Pseudomonas aeruginosa, Proteus mirabilis and methicillin-susceptible Staphylococcus aureus. The Kruskal-Wallis test revealed that HbA1c concentrations were different in groups infected with different strains of bacteria (p = 0.0087). Isolation of Escherichia coli and Morganella morganii was more often associated with poor control of diabetes. Conclusions: The study revealed statistically significant differences in the frequency of microorganisms isolated from the wounds of patients with DFU. The discrepancies in the results of other studies published in this field indicate the need for standardization of the research design.

The Influence of Multidrug-Resistant Bacteria on Clinical Outcomes of Diabetic Foot Ulcers: A Systematic Review

Multidrug-resistant organism infections have become important in recent years due to the increased prevalence of diabetic foot ulcers and their possible consequences. This study aimed to systematically review and evaluate ulcer duration, healing time, hospital stay, amputation, and mortality rates in patients with diabetic foot ulcers caused by infection with multidrug-resistant organisms. PubMed, the Cochrane Library, and Web of Science were searched in May 2020 to find observational studies in English about the clinical outcomes of multidrug-resistant organism infection in diabetic foot ulcers. Eight studies met the inclusion criteria, and these studies included 923 patients. The overall methodological quality of the study was moderate. Ulcer duration was described in six studies, and there was no practical association with multidrug-resistant organisms. Two out of three studies reported a longer healing time in multidrug-resistant organism infections than in non-multidrug-resistant organism infections. Clinical outcomes included the duration of hospitalisation, surgeries, amputations, and deaths. Lower limb amputation was the most reported clinical outcome in the included studies, and was more prevalent in the multidrug-resistant organism infections. We concluded that there was not enough evidence that multidrug-resistant organisms hindered the healing of diabetic foot ulcers. In contrast to the clinical outcomes, multidrug-resistant organisms affect both amputation rates and mortality rates.

Multicentre study of the burden of multidrug-resistant bacteria in the aetiology of infected diabetic foot ulcers

Background

Infected diabetic foot ulcer (IDFU) is a public health issue and the leading cause of non-traumatic limb amputation. Very few published data on IDFU exist in most West African countries.

Objective

The study investigated the aetiology and antibacterial drug resistance burden of IDFU in tertiary hospitals in Osun state, Nigeria, between July 2016 and April 2017.

Methods

Isolates were cultured from tissue biopsies or aspirates collected from patients with IDFU. Bacterial identification, antibiotic susceptibility testing and phenotypic detection of extended-spectrum beta-lactamase and carbapenemase production were done by established protocols. Specific resistance genes were detected by polymerase chain reaction.

Results

There were 218 microorganisms isolated from 93 IDFUs, comprising 129 (59.2%) Gram-negative bacilli (GNB), 59 (27.1%) Gram-positive cocci and 29 (13.3%) anaerobic bacteria. The top five facultative anaerobic bacteria isolated were: Staphylococcus aureus (34; 15.6%), Escherichia coli (23; 10.6%), Pseudomonas aeruginosa (20; 9.2%), Klebsiella pneumoniae (19; 8.7%) and Citrobacter spp. (19; 8.7%). The most common anaerobes were Bacteroides spp. (7; 3.2%) and Peptostreptococcus anaerobius (6; 2.8%). Seventy-four IDFUs (80%) were infected by multidrug-resistant bacteria, predominantly methicillin-resistant S. aureus and GNB producing extended-spectrum β-lactamases, mainly of the CTX-M variety. Only 4 (3.1%) GNB produced carbapenemases encoded predominantly by bla _VIM. Factors associated with presence of multidrug-resistant bacteria were peripheral neuropathy (adjusted odds ratio [AOR] = 4.05, p = 0.04) and duration of foot infection of more than 1 month (AOR = 7.63, p = 0.02).

Conclusion

Multidrug-resistant facultative anaerobic bacteria are overrepresented as agents of IDFU. A relatively low proportion of the aetiological agents were anaerobic bacteria.

Distribution and Antibiotic Resistance Patterns of Pathogenic Bacteria in Patients With Chronic Cutaneous Wounds in China

Background: To determine the distribution and antimicrobial susceptibility pattern of pathogenic bacteria in patients with chronic cutaneous wounds on a national scale. Methods: A retrospective study was conducted using the data recorded between January 1, 2018 and January1, 2020 in 195 hospitals across China. After screening the data, 815 patients with chronic wounds were finally analyzed. The data collected included information about the patients' general condition and local cutaneous wound assessments, especially microbial culture and antibiotic susceptibility tests. The analyses were performed using SPSS Version 26. Results: The study included 815 patients (290 [35.6%] females; 63 [50-74] years). The most common causes of chronic cutaneous wounds were diabetes (183, 22.5%), infection (178, 21.8%), and pressure (140, 17.2%). Among these, 521(63.9%) samples tested yielded microbial growth, including 70 (13.4%) polymicrobial infection and 451 (86.6%) monomicrobial infection. The positive rate of microbial culture was highest in wound tissue of ulcers caused by infection (87.6%), followed by pressure (77.1%), diabetes (68.3%), and venous diseases (67.7%). Bates-Jensen wound assessment tool (BWAT) scores >25 and wounds that lasted for more than 3 months had a higher positive rate of microbial culture. BWAT scores >25 and wounds in the rump, perineum, and feet were more likely to exhibit polymicrobial infection. A total of 600 strains were isolated, of which 46.2% (277 strains) were Gram-positive bacteria, 51.3% (308 strains) were Gram-negative bacteria, and 2.5% (15 strains) were fungi. The most common bacterial isolates were Staphylococcus aureus (29.2%), Escherichia coli (11.5%), Pseudomonas aeruginosa (11.0%), Proteus mirabilis (8.0%), and Klebsiella pneumoniae (5.8%). The susceptibility tests showed that 116 cultured bacteria were Multidrug resistant (MDR) strains. The resistance rates of S. aureus were 92.0% (161/175) to penicillin, 58.3% (102/175) to erythromycin, and 50.9% (89/175) to clindamycin. Vancomycin was the most effective antibiotic (0% resistance rate) against all Gram-positive bacteria. Besides, the resistance rates of E. coli were 68.1% (47/69) to ampicillin, 68.1% (47/69) to ciprofloxacin, 60.9% (42/69) to levofloxacin. However, all the isolated Gram-negative bacteria showed low resistance rates to tigecycline (3.9%) and amikacin (3.6%). Conclusions: The distribution of bacteria isolated from chronic cutaneous wounds varies with the BWAT scores, causes, duration, and the location of wounds. Multidrug resistance is a serious health issue, and therefore antibiotics used in chronic wounds must be under strict regulation. Our findings may help clinicians in making informed decisions regarding antibiotic therapy.

Spectral and Antibiotic Susceptibility of Pathogens Isolated from Saudi Patients with Diabetic Foot Infections

Diabetic foot infections (DFIs) are a significant health issue and a common complication among patients with diabetes. To develop antibiotic therapy for these high-risk patients, the current study evaluates the scope of DFIs and identifies the causing microbes. It also measures spectrum and antibiotic susceptibility of the pathogens isolated from adults with DFIs in Saudi Arabia. To achieve the study objectives, a cross-sectional study was implemented and the baseline characteristics for 44 patients with DFIs were defined. Optimal aerobic and anaerobic microbiological techniques were utilized to culture specimens isolated from infected foot ulcers. The standard microbiological methods were employed to identify the bacterial isolates and antibiotic susceptibility testing was conducted following the procedures of the Clinical and Laboratory Standards Institute (CLSI). Results showed that 12 microorganisms were isolated from the participants’ diabetic foot ulcers. Staphylococcus Aureus was ranked first because it appeared in 29 (65.9%) cases. Streptococcus Agalactiae was ranked second and multi-microbial infections were also found. Most of the organisms were susceptible to Vancomycin, Ciprofloxacin, and Cefalexin, but they were resistant to Methicillin, Gentamicin, and Ampicillin antibiotics. Staphylococcus Aureus was most sensitive to Ciprofloxacin, while it was resistant to Methicillin. About 10% of the isolates were multidrug-resistant. The study concludes that while Vancomycin should be used empirically for Gram-positive isolates, Ciprofloxacin can be taken into consideration for most of the Gram-negatives aerobes. Based on including various microorganisms and the advent of multidrug-resistant strains, proper culture and sensitivity testing are necessary prior to the empirical therapy.

A peptide-based aggregation-induced emission bioprobe for selective detection and photodynamic killing of Gram-negative bacteria

A bioprobe with aggregation-induced emission characteristics is developed, which can visualize and photodynamically ablate Gram-negative bacteria in a selective manner.

Diabetic foot infection and osteomyelitis. Are deep-tissue cultures necessary?

Introduction

Diabetic foot infections (DFIs) are common and difficult to treat. The objective of this study was to compare swab and tissue cultures as indicators of appropriate treatment of DFIs.

Methods

This is a prospective study conducted during a 4-year period. All patients with DFIs and/or diabetic foot osteomyelitis (DFO) admitted to the University Hospital of Heraklion, Greece, were included. Clinical data were collected, while cultures taken with swabs and/or tissue biopsies were used as indicators of the microbiological cause and the appropriate treatment.

Results

In total, 83 individuals (62.7% males) with mean age of 72 years, were enrolled. Coexisting osteomyelitis was present in 18.1%. From tissue and pus cultures, 131 and 176 pathogens, respectively, were isolated. Gram-positive aerobes were the most common microorganisms, followed by Gram-negatives. Infection was polymicrobial in 40 (70.2%) out of 57 patients with tissue culture and in 54 (75.0%) out of 72 with pus culture. Microbiological results from tissue cultures were compatible with those from pus at a rate of 80%, while in cases of osteomyelitis concordance reached 100%. Multidrug-resistant organisms (MDROs) were isolated from 32 (24.4%) tissue and 44 (25%) pus cultures (p=0.910). Initial empirical antimicrobial treatment was considered inappropriate in 44.6% of cases.

Conclusions

A high concordance between easily taken swab cultures and those taken by biopsy was noted, especially in DFO. This was helpful for early change to appropriate treatment in cases where MDROs were isolated and empirical treatment was inappropriate. Further research is needed to confirm this observation in clinical practice.

Bacterial ecology and antibiotic resistance mechanisms of isolated resistant strains from diabetic foot infections in the north west of Algeria

BACKGROUND

In front of the polymorphic bacterial ecology and antibiotic resistance in diabetic patients with foot infections and good patient care, collaboration between clinicians and microbiologists is needed to improve assessment and management of patients with this pathology.

OBJECTIVE

This study was designed to characterize the bacterial ecology of diabetic foot infection (DFIs) and to determine the different mechanisms of resistance involved.

METHODS

In this study bacterial strains and antibiotic resistance profiles were determined from diabetic foot infections patients (n = 117). The identification of resistance mechanisms, such as penicillinase and/or extended-spectrum β-lactamase production (ESBL), methicillin-resistant Staphylococcus aureus (MRSA) and efflux pump over-expression were performed.

RESULTS

A high prevalence of Gram-negative bacteria (61%) with Escherichia coli, and other Enterobacteriaceae and Pseudomonas aeruginosa being the predominant isolates. Gram positive bacteria mainly represented by Staphylococcus aureus accounted for 39% of the isolates. 93.5% of the Enterobacteriaceae were resistant to, at least, one molecule in the β-lactam family, while the majority of the Staphylococci were resistant to penicillin G and tetracycline (93.3% and 71.7%). The majority of non-fermenting Gram negative bacteria were also resistant to fluoroquinolones. β-lactamase detection tests revealed the presence of extended-spectrum β-lactamase in 43.5% of the Enterobacteriaceae, while methicillin-resistant Staphylococcus aureus represented 18.2% of the isolates. Additionally, 50.9% of non-fermenting Gram negative bacteria were overproducing efflux pumps.

CONCLUSION

All Acinetobacter Baumannii were Multidrug-Resistant (MDR), as the majority of Staphylococci, and Enterobacteriaceae. These results should be taken into account by the clinician in the prescription of probabilistic antibiotic therapy in this context.

Bacteriological profile and antibiotic susceptibility of diabetic Foot infections at Ribat University hospital; a retrospective study from Sudan

Purpose

Diabetic foot infection (DFI) is one of the most feared complications of diabetes. In Sudan, the number of cases and the problems associated with diabetic foot infections increased in recent years. This study aimed to assess the bacteriological profile of patients with DFIs and their antibiotic susceptibility pattern.

Methods

A descriptive retrospective cross-sectional study was carried out at Surgery Department of Ribat University Hospital. All medical records of patients with DFIs during the period from September 2017 to February 2019 were reviewed using data collection sheet. The collected data were analyzed using Statistical Package for Social Sciences.

Results

Out of 250 DFI patients, 73.2% of them were males, and 86.4% of them had type 2 diabetes mellitus, and most of them suffered from diabetes for more than 10 years. Regarding culture results, 64.7% and 35.3% of the samples revealed presence of single microorganism and mixed infections, respectively. A total of 335 bacterial isolates were identified, gram-negative were more prevalent than gram-positive organisms. The most frequently isolated organisms were Proteus spp. Staphylococcus aureus, and Escherichia coli. Furthermore, antibiotic susceptibility pattern showed that imipenem, amikacin and vancomycin have the highest activity against isolated bacteria, and all isolates were found to be completely resistant to different cephalosporin drugs.

Conclusion

Among the studied samples, gram-negative bacteria were found to be more common in DFI patients, Proteus spp. and S. aureus were the most common microorganisms. Moreover, different isolated microorganisms showed to have different degrees of resistance and sensitivity to various antibacterial drugs.

Detection of Biofilm Production and Its Impact on Antibiotic Resistance Profile of Bacterial Isolates from Chronic Wound Infections

Background:

Microorganisms are known to be involved in the formation of biofilm. These biofilms are often seen in chronic wound infections, surgical site infections, implants etc., These are capable of causing recalcitrant infections and most of them are also known to possess high antibiotic resistance.

Objectives:

This study was conducted to detect the biofilm formation in bacterial isolates from chronic wound infections.

Materials and Methods:

In the present study, ninety two isolates from chronic wound infections were identified by MALDI-TOF-MS (bioMerieux) and VITEK-2-MS (bioMerieux). These isolates were further screened for biofilm formation by three methods i. e., Tissue Culture Plate method (TCP), Tube Method (TM) and Congo Red Agar (CRA) method. Impact of biofilm production was correlated with the antibiotic resistant pattern.

Statistical Analysis:

Statistical analysis was done for all three methods considering TCP as Gold Standard and parameters like senitivity and specificity of TM i.e. 47.2 and 100% respectively.

Results:

Out of 92 isolates, biofilm formation was seen in 72 isolates (78.2%) by TCP method. 64 isolates were strong biofilm producers, 8 isolates were moderate biofilm producers and 20 isolates were nonbiofilm producing. High prevalence of biofilm formation was seen in nonhealing ulcers infected with Staphylococcus aureus followed by Klebsiella pneumoniae.

Conclusion:

Among three screening methods used for detection of biofilm production, TCP method is considered to be a standard and most reliable for screening of biofilm formation in comparison to TM and CRA.

A study on diabetic foot ulcers in Central rural India to formulate empiric antimicrobial therapy

AIM

This study was carried out on patients with diabetic foot ulcer (DFU) to assess the clinical characteristics, spectrum of microbial flora, antibiotic sensitivity, and devise an empiric antimicrobial therapy.

MATERIAL METHODS

Clinical data and tissue samples were collected from 105 diabetic foot ulcer patients between December 2018 and November 2019. The collected samples were processed as per Clinical and Laboratory Standards Institute guidelines and clinical and microbiological data was analyzed.

RESULTS

In this study of 105 patients, DFU was most common in males in 5th and 6th decade of life. Majority of patients had poor glycemic control and neuropathy. Of 110 bacterial isolates obtained from 97 samples, 73.7% were Gram-negative bacteria, and 27.3% were Gram-positive. Most of samples (48.6%) showed growth of single bacteria, growth of two bacteria and polymicrobial growth was seen in 28.6% and 15.2% of tissue samples respectively of which. Pseudomonas was predominant isolate (27.3%) sensitive to imipenem (90%), amikacin (86.6%), gentamicin (83.3%), and cefotaxime (80%) followed by Staphylococcus aureus (19.1%) sensitive to amikacin and gentamicin (100%), and ofloxacin (90%). Pseudomonas, E. coli, Proteus and Klebsiella were highly resistant to ampicillin and amoxicillin-clavulanic acid.

CONCLUSION

This study showed DFU are common in 5th and 6th decades of life. Gram-negative bacteria are predominant infective organism. Most of both Gram-negative and Gram-positive bacteria are resistant to variable degrees to commonly used antibiotics and sensitive to aminoglycosides. Amikacin and gentamicin can be used as empiric antibiotics for treatment of DFU infections.

Frequency and Antimicrobial Susceptibility Patterns of Diabetic Foot Infection of Patients from Bandar Abbas District, Southern Iran

Diabetic foot infection is among the most common complications of diabetes mellitus which significantly causes hospitalization and is the most prevalent etiology of nontraumatic amputation worldwide. The current study aimed at assessing the frequency and antimicrobial susceptibility patterns of diabetic foot infection of patients from the Bandar Abbas area, in the south of Iran. In this study, a total of 83 diabetic patients with diabetic infected foot wounds referring to Shahid Mohammadi Hospital, Bandar Abbas, from 2017 to 2018 were assessed. Samples were obtained from wound sites and evaluated by aerobic culture and also an antibiogram test for antibiotic susceptibility. Factors including age, sex, type of diabetes, the medication used for diabetes, previous history of diabetic foot infection, duration of wound incidence, fever, and laboratory indices were recorded for each subject. The most prevalent detected bacteria were Escherichia coli (20.5%), Enterococcus sp. (16.9%), Klebsiella sp. (12%), Staphylococcus aureus (8.4%), Enterobacter sp. (7.2%), and Acinetobacter sp. (6%). The results of antibiogram tests revealed the most and the least antibiotic sensitivity for E. coli sp. as meropenem and ciprofloxacin, for Enterococcus sp. as gentamicin and ciprofloxacin, for Klebsiella sp. as amikacin and cotrimoxazole, and for Enterobacter sp. as cotrimoxazole and both amikacin and ciprofloxacin. Staphylococcus aureus was sensitive to vancomycin and doxycycline, and Acinetobacter sp. was 100% resistant to all antibiotics except amikacin and gentamycin. A significant statistical association was found between the C-reactive protein and the patients' diabetic foot infection organisms (P=0.019). Findings of the study revealed E. coli sp. as the most common bacteria which are infecting the foot lesions in the studied population. The highest antibiotic susceptibility was seen for vancomycin, linezolid, and carbapenem.

Determination of antimicrobial effect of protamine by transmission electron microscopy and SDS PAGE on Pseudomonas aeruginosa isolates from diabetic foot infection

Objective(s):

Diabetic foot infection is one of the major complications of diabetes leading to lower limb amputations. Isolation and identification of bacteria causing diabetic foot infection, determination of antibiotic resistance, antimicrobial potential of protamine by electron microscopy and SDS-PAGE analysis, arethe aims of this study.

Materials and Methods:

285 pus samples from diabetic foot infection patients were collected from different hospitals of Karachi and Capital Health Hospital, Halifax, Canada. Clinical history of each patient was recorded. Bacterial isolates were cultured on appropriate media; identification was done by morphology, cultural and biochemical tests. Effect of protamine against multi drug resistant strains of Pseudomona aeruginosa was checked by minimum inhibitory concentration in 96 well micro-titer plates. The isolates were grown in bactericidal concentration of protamine on plates to isolate mutants. Effect of protamine on protein expression was checked by SDS- PAGE and ultra-structural morphological changes by transmission electron microscopy.

Results:

Results indicated prevalence of foot infection as 92% in diabetic patients. Major bacterial isolates were Staphylococcus aureus 65 (23%), P. aeruginosa 80 (28.1%), Klebsiella spp. 37 (13%), Proteus mirabilis 79 (27.7%), and Escherichia coli 24 (12%). These isolates were highly resistant to different antibiotics. MIC value of protamine was 500 µg/ml against P. aeruginosa. SDS-PAGE analysis revealed that protamine can suppress expression of various virulence proteins and electron micrographs indicated condensation of cytoplasm and accumulation of protamine in cytoplasm without damaging the cell membrane.

Conclusion:

P. aeruginosa and S. aureus were the major isolates expressing multi-drug resistance and protamine sulfate represented good antimicrobial potential.

The Impact of Multidrug-Resistant Organisms on Outcomes in Patients With Diabetic Foot Infections

Background

Multidrug-resistant organisms (MDROs) are important diabetic foot infection (DFI) pathogens. This study evaluated the impact of DFIs associated with MDRO pathogens (DFI-MDRO) on clinical outcomes.

Methods

Adults admitted to Detroit Medical Center from January 2012 to December 2015 with culture-positive DFI were included. Associations between outcomes and DFI-MDRO (evaluated as a single group that included methicillin-resistant Staphylococcus aureus [MRSA], vancomycin-resistant enterococci, Enterobacteriaceae resistant to third-generation cephalosporin [3GCR-EC], Acinetobacter baumannii, and Pseudomonas aeruginosa) were analyzed. Outcomes included above- and below-knee lower extremity amputation (LEA), readmissions, and mortality within a year after DFI. A propensity score predicting the likelihood of having DFI-MDRO was computed by comparing patients with DFI-MDRO with patients with DFI with non-MDRO pathogens (DFI-non-MDRO). Using conditional logistic regression, DFI-MDRO was analyzed as an independent variable after patients in the MDRO and non-MDRO groups were matched by propensity score.

Results

Six hundred forty-eight patients were included, with a mean age ± SD of 58.4 ± 13.7. Most patients in the cohort presented with chronic infection (75%). DFI-MDRO occurred in greater than one-half of the cohort (n = 364, 56%), and MRSA was the most common MDRO (n = 224, 62% of the DFI-MDRO group). In propensity-matched analyses, DFI-MDRO was not associated with 1-year LEA or readmissions, but was associated with recurrent DFI episodes (odds ratio, 2.1; 95% confidence interval, 1.38-3.21).

Conclusions

DFI-MDRO was associated with a 2-fold increased risk of recurrent DFI compared with patients with DFI-non-MDRO.

Evaluation of various risk factors associated with multidrug-resistant organisms isolated from diabetic foot ulcer patients

AIMS:

Diabetic foot ulcer is a dreaded complication of diabetes. Diabetic foot ulcer patients are often infected with multidrug resistant organism (MDRO) due to chronic course of the wound, inappropriate antibiotics treatment, frequent hospital admission, neuropathy, nephropathy, and peripheral vascular disease.

MATERIALS AND METHODS:

This prospective study was conducted in our 750 bedded hospital for a period of 6 months. The present study was undertaken to isolate various MDRO methicillin resistant Staphylococcus aureus; Gram-negative bacteria producing enzymes such as extended spectrum beta-lactamases (ESBL), Amp C, Carbapenamases; Pseudomonas and Acinetobacter species producing metallo-beta-lactamases (MBL). In addition we attempted to identify risk factors for association of diabetic foot ulcer and MDRO.

RESULTS:

A total of 149 bacterial isolates were identified. Of the total isolates 73.2% were Gram-negative and remaining 26.8% were Gram-positive bacteria. Among Enterobacteriaceae 59% were ESBL producers and 48% were Amp C producers. In addition, 41.5% of the isolates produced both ESBL and Amp C and 13.4% were carbapenem resistant Enterobacteriaceae. Among 20 Pseudomonas and Acinetobacter isolates, 5 were MBL producers (25%). Furthermore, in the study, 56% of patients with diabetic foot ulcer harbored MDRO. The risk of multidrug-resistant infection is significantly more in patients having diabetes duration >20 years and size of ulcer more than 4 cm².

CONCLUSION:

The detection of MDRO in patients of diabetic foot ulcer changes the treatment strategies limits the antimicrobial options and causes higher complications among them.

Emergence of Fluconazole-resistant Candida Infections in Diabetic Foot Ulcers: Implications for Public Health

Background:

It is well documented in the literature that fungal infections are common in diabetic foot ulcers (DFUs). This has led to an overuse of antifungal agents, namely fluconazole, with a consequent risk of emergence of resistance to this drug. Previous studies have shown a 3.9% prevalence of fluconazole resistance in DFU, but limited data exist regarding the change in resistance pattern over the last decade.

Objectives:

Our aim was to study the prevalence of resistance to fluconazole in patients with DFU and culture-proven fungal infections.

Materials and Methods:

We retrospectively studied 1438 patients with type 2 diabetes and nonhealing foot ulcers who had fungal cultures performed during the course of their treatment. The data were collected for all patients who presented to our foot clinic over a period of 18 months.

Results:

The prevalence of positive fungal culture was 17.38% (250/1438). 151/200 positive cultures belonged to Candida species. Resistance to fluconazole was observed in 9.3% (17/200). The most common organism with resistance to fluconazole was Candida auris (10/17).

Conclusions:

High prevalence of fluconazole resistance is a potential cause of concern, and the rational use of this drug is important in the community. The above results could have an impact on public health, as fluconazole is one of the safest and effective oral antifungal agents available. The spread of resistance could have implications for its use in other situations including systemic fungal infections.

Assessment of the Risk Factors of Multidrug-Resistant Organism Infection in Adults With Type 1 or Type 2 Diabetes and Diabetic Foot Ulcer

OBJECTIVES

To our knowledge, this is the first review to analyze the literature identifying risk factors for multidrug-resistant organism (MDRO) infection in patients with diabetic foot ulcer. The purpose of this study was to collect the currently published data to determine the most commonly and consistently identified risk factors for MDRO infection.

METHODS

PubMed, MEDLINE, BIOSIS, Web of Science and the Cochrane Library electronic databases were searched. The last search updated was in September 2019. The evaluated outcomes included age, male sex, type of diabetes, diabetes duration, level of glycated hemoglobin, ulcer type, wound duration, ulcer size, ulcer grade, osteomyelitis, previous antibiotic therapy and previous hospitalization. The standard mean difference or the odds ratio (OR) was calculated for continuous or dichotomous data, respectively. The quality of the studies was assessed, and meta-analyses were performed with Cochrane Collaboration's RevMan 5.0 software.

RESULTS

A total of 11 studies, including 1,229 patients provided evidence for 6 possible risk factors for MDRO infection. Ischemic ulcer (OR, 0.50; 95% confidence interval [CI], 0.35 to 0.71), ulcer size (standard mean difference, -0.27; 95% CI, -0.46 to -0.08), ulcer grade (OR, 0.36; 95% CI, 0.15 to 0.83), osteomyelitis (OR, 0.33; 95% CI, 0.25 to 0.45), previous antibiotic therapy (OR, 0.08; 95% CI, 0.04 to 0.14) and previous hospitalization (OR, 0.15; 95% CI, 0.08 to 0.28) were identified as risk factors for MDRO infection in patients with diabetic foot ulcer.

CONCLUSIONS

Our meta-analysis indicated that ischemic ulcer, ulcer size, ulcer grade, osteomyelitis, previous antibiotic therapy and previous hospitalization were associated with MDRO infection in patients with diabetic foot ulcer.

Combinatorial Drug Therapy for Controlling Pseudomonas aeruginosa and Its Association With Chronic Condition of Diabetic Foot Ulcer

Diabetic foot ulcer (DFU) is a major complication of diabetes mellitus, major observations of DFU cases have reported on amputation of foot region, and microbial bioburden during DFU is a major cause that affects healing of the wound regions. Pathogenic microbes are routinely isolated from these wound regions, especially Staphylococcus, Pseudomonas, Klebsiella, and Escherichia coli have been reported, whereas higher prevalence of Pseudomonas species during chronic condition in the deeper part of the wound, when left untreated, leads to gangrene. Multiple drug-resistant Pseudomonas strains are a new threat because of their biofilm-forming ability, making it more potent and incurable. Acyl homoserine lactones (AHL) are a group of signaling molecules that can regulate biofilm growth, and Las and Rhl operon generally work in tandem to initiate biofilm formation by Pseudomonas species. These signaling molecules also initiate virulence factors that correlates upregulation of inflammatory responses, and AHL can be a therapeutic target in order to prevent the efficacy of multiple drug-resistant strains that form biofilm and also can be an alternative solution against control of multiple drug-resistant strains.