Bacterial Profile and Antimicrobial Resistance Patterns of Diabetic Foot Infections in a Major Research Hospital of Turkey

Background/Aim: Diabetic foot infection (DFI) occurs frequently in patients, followed up with diabetic foot ulcers (DFU). For this reason, antibiotic treatment is often used in patients followed with DFU. Inappropriate use of antibiotics and increasing antibiotic resistance threaten public health. We aimed to investigate the microbial spectrum and antimicrobial resistance patterns isolated from diabetic foot infections in Turkey and help clinicians to choose optimal antibiotics empirically. Materials and Methods: This study was planned as a retrospective, single-center, cross-sectional study. Two hundred sixty-two patients whose causative microorganism was isolated in culture of tissue between 1 January 2021 and 31 December 2022 were included in this study. Bacterial profile and antimicrobial resistance patterns were analyzed. Results: Four hundred thirty two isolates from 262 patients isolated in culture of tissue were evaluated. Of these microorganisms, 57.60% were Gram-negative, 41.20% were Gram-positive bacteria, and 1.2% were Candida spp. The most frequently detected Gram-positive microorganism was Staphylococcus spp. Gram-negative microorganisms were Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa). Polymicrobial infections were observed in 40.5% of the patients. Methicillin-resistant Staphylococcus spp. rate was 51.3%, while extended-spectrum beta-lactamase (ESBL) resistance for E. coli was 66.7%. Conclusions: Due to increasing antibiotic resistance rates, treatment of common infections becomes more difficult. Knowledge of the microbiological profile and antibiotic resistance patterns of patients with DFIs is useful to guide empirical therapy.

Extensively drug-resistant Pseudomonas aeruginosa: clinical features and treatment with ceftazidime/avibactam and ceftolozane/tazobactam in a tertiary care university hospital center in Portugal - A cross-sectional and retrospective observational study

Introduction

Extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) is a growing concern due to its increasing incidence, limited therapeutic options, limited data on the optimal treatment, and high mortality rates. The study aimed to characterize the population, the outcome and the microbiological characteristics of XDR-PA identified in a Portuguese university hospital center.

Methods

All XDR-PA isolates between January 2019 and December 2021 were identified. XDR-PA was defined as resistance to piperacillin-tazobactam, third and fourth generation cephalosporins, carbapenems, aminoglycosides and fluoroquinolones. A retrospective analysis of the medical records was performed.

Results

One hundred seventy-eight individual episodes among 130 patients with XDR-PA detection were identified. The most common sources of infection were respiratory (32%) and urinary tracts (30%), although skin and soft tissue infections (18%) and primary bacteremia (14%) were also prevalent. Colonization was admitted in 64 cases. Several patients had risk factors for complicated infections, most notably immunosuppression, structural lung abnormalities, major surgery, hemodialysis or foreign intravascular or urinary devices. XDR-PA identification was more frequent in male patients with an average age of 64.3 ± 17.5 years. One non-susceptibility to colistin was reported. Only 12.4% were susceptible to aztreonam. Ceftazidime-avibactam (CZA) was susceptible in 71.5% of the tested isolates. Ceftolozane-tazobactam (C/T) was susceptible in 77.5% of the tested isolates. Antibiotic regimens with XDR-PA coverage were reserved for patients with declared infection, except to cystic fibrosis. The most frequently administered antibiotics were colistin (41 cases), CZA (39 cases), and C/T (16 cases). When combination therapy was used, CZA plus colistin was preferred. The global mortality rate among infected patients was 35.1%, significantly higher in those with hematologic malignancy (50.0%, p < 0.05), followed by the ones with bacteremia (44.4%, p < 0.05) and those medicated with colistin (39.0%, p < 0.05), especially the ones with respiratory infections (60.0%). Among patients treated with CZA or C/T, the mortality rate seemed to be lower.

Discussion

XDR-PA infections can be severe and difficult to treat, with a high mortality rate. Even though colistin seems to be a viable option, it is likely less safe and efficient than CZA and C/T. To the best of the authors' knowledge, this is the first description of the clinical infection characteristics and treatment of XDR-PA in Portugal.

Prevention and management of foot and lower limb health complications in adults undergoing dialysis: a scoping review

BACKGROUND

Foot and lower limb health complications are common among patients undergoing dialysis; but a summary of prevention and management evidence is not available. The aim of this scoping review was to summarise study characteristics and the nature of results regarding strategies to prevent and manage peripheral arterial disease (PAD), foot ulceration, amputation, associated infection and associated hospital admission in adults undergoing dialysis.

METHODS

MEDLINE, Embase, CINAHL and AMED databases were searched for longitudinal experimental and observational studies. Eligible studies included adults undergoing dialysis (≥10 dialysis patients, with separate results or ≥ 75% of the cohort). Any interventions relating to PAD, foot ulceration, amputation, associated infection, and associated hospital admission were included.

RESULTS

The review included 212 studies, of which 199 were observational (94%) and 13 were experimental (6%). Sixteen studies (8%) addressed the prevention of foot and lower limb health complications, 43 (20%) addressed management, and 153 (72%) addressed both. The main intervention type in each study was surgery (n = 159, 75%), care from one or more health professionals (n = 13, 6%), screening by a health professional (n = 10, 5%), medication (n = 9, 4%) and rehabilitation (n = 5, 2%). No studies were identified where exercise, offloading or education were the main intervention. Results for PAD were reported in 137 (65%) studies, foot ulceration in 54 (25%), amputation in 171 (81%), infection in 7 (3%), and admission in 26 studies (12%). Results for more than one foot or lower limb outcome were reported in 141 studies (67%), with each study reporting on average two outcomes. Results varied and spanned positive, negative, and neutral outcomes following intervention.

CONCLUSIONS

Identified studies frequently aimed to both prevent and manage foot and lower limb health complications. A variety of interventions were identified and studies often reported results for more than one foot or lower limb health outcome. Findings from this review can be used to guide future research, with a goal to support improved patient outcomes.