José María Rojas‐Bonilla

The purpose of this study was to examine whether polymicrobial infection in bone biopsies is associated with infection relapse following surgery for diabetic foot osteomyelitis. Relapse of infection presents a major challenge in treating diabetic foot osteomyelitis, yet the role of microbiological factors in predicting relapse remains underexplored. We conducted a retrospective analysis of 100 patients treated surgically for diabetic foot osteomyelitis. Bone biopsies were obtained intraoperatively for microbiological and histopathological examination. Relapse was defined as the recurrence of infection in bone or soft tissue necessitating additional surgical intervention or antibiotic therapy. Our findings indicate that soft tissue involvement, rather than polymicrobial infection in bone biopsies, is a significant predictor of relapse, with patients exhibiting soft tissue involvement showing a markedly higher likelihood of relapse. In contrast, polymicrobial growth in bone biopsies was not significantly associated with infection relapse. These results highlight the importance of soft tissue integrity in treatment outcomes and suggest that local tissue damage, rather than microbiological diversity, may play a more critical role in relapse. This study challenges the assumption that polymicrobial infection directly influences relapse risk and raises questions regarding the reliance on wound healing as an indicator of successful infection management. Future studies should focus on refining treatment indicators and exploring comprehensive approaches that address both bone and soft tissue infections to reduce relapse rates and improve patient outcomes.

Diabetic foot infections (DFIs) and diabetic foot osteomyelitis (DFO) are common and serious complications in patients with diabetes, often leading to severe morbidity (including amputation) and even mortality. Professional footcare, prompt diagnosis and appropriate treatment are crucial to preventing limb loss and improving outcomes in infections. This narrative review addresses the management of all DFIs, including the approach to clinical evaluation, appropriate diagnostic methods, and optimal therapeutic strategies. We specifically address key areas in antibiotic therapy, and surgical interventions and techniques. Based on our literature review and extensive, multidisciplinary experience, we developed a novel treatment flowchart specifically for the management of DFO. Managing DFIs, including DFO, requires a multidisciplinary approach tailored to each patient's clinical presentation. While antibiotics, surgery, and wound care each play a crucial role, the decision-making process should always consider the infection's severity and chronicity. Our proposed flowchart for DFO management emphasizes the importance of logically-sequenced, easy to apply and tailored interventions to prevent unnecessary amputations and improve outcomes. Further research is needed to further refine this flowchart in clinical practice and demonstrate its effectiveness.

Aims: We hypothesize that microbiology‐ and pathology‐confirmed positive bone margins after the resection of diabetes‐related foot osteomyelitis are associated with worse outcomes.Methods: We conducted a prospective study consisting of a cohort of 93 patients with diabetes‐related foot osteomyelitis (histopathology confirmed) who underwent bone resection and where an additional bone biopsy was taken at the resection margin. The primary outcome was the recurrence of the infection.Results: Pathology‐confirmed positive margins were detected in 62 cases (66.7%), microbiology‐confirmed positive margins were detected in 75 cases (80.6%) and recurrence was detected in 19 patients (20.4%). Chi‐squared test failed to show the presence of an association between the recurrence of the infection with pathology‐confirmed positive margins (p = 0.82), with microbiology‐confirmed positive margins, (p = 0.34) and with the use of postoperative antibiotics (p = 0.70). Healing in patients with pathology‐confirmed positive margins was achieved in a median of 12 weeks (95% CI 9.2‐18) and those with pathology‐confirmed negative margins in 14.9 weeks (95% CI 10.2‐21.9), Log‐rank test, p = 0.74. Thirty‐four patients out of 61 available for follow‐up (55.7%) with pathology‐confirmed positive margins were treated without postoperative antibiotics. In that group, Chi‐squared test failed to show the presence of an association between the recurrence of the infection with the use of postoperative antibiotics (p = 0.47).Conclusions: A positive margin was neither associated with the recurrence of the infection nor with the time to healing. More than half of patients with pathology‐confirmed positive margins were treated without postoperative antibiotics and this approach was not associated with the recurrence of the infection.

Objective: To identify clinical and sociodemographic factors associated with mortality in patients hospitalized for diabetic foot, in the Diabetic Foot Unit of the San Juan de Dios Hospital in Costa Rica, from 2017 to 2019. Materials and methods: A retrospective cohort study with 238 patients, followed from hospitalization until death or until December 31, 2021, still alive. A descriptive analysis is made of the sociodemographic, clinical, and cause of death variables. A Cox proportional hazards model is run for all causes of death, and another exclusively for death from cardiovascular causes. Survival times are analyzed using Kaplan-Meier curves, with the log-rank test for comparison. Results: Most of the deceased were men, did not have a partner, lived in urban or predominantly urban areas, were 15 years or older, diabetic, hypertensive, with peripheral arterial disease, anemia, inadequate glycosylated hemoglobin, and obesity. The mortality rate was 23,53%, and cardiovascular disease was the main cause of death (35,70%). The variables associated with all-cause mortality, adjusted for age and sex were: absence of a partner (HR: 13,09; 95% CI: 4,04-42,31), obesity (HR: 2,89; 95% CI %: 1,59-5,27), peripheral arterial disease (HR: 2,26; CI 95%: 1,25-4,09), years of evolution of diabetes mellitus ≥ 15 years (HR: 1,99; CI 95 %: 1,04-3,82). In turn, for cardiovascular mortality were: obesity (HR: 6,42; 95% CI: 2,07-19,87), peripheral arterial disease (HR: 3,88; 95% CI: 1,39-10,79) and heart disease (HR: 4,11; 95% CI: 1,62-10,46). Conclusions: Evolution of diabetes mellitus greater than or equal to 15 years, not having a partner, obesity and peripheral arterial disease were associated with all-cause mortality. Regarding death from cardiovascular disease, the associated variables were obesity, peripheral arterial disease, and heart disease.

We aimed to validate the prognostic value of subclassifying moderate diabetic foot infections into two categories: moderate and moderate/severe. We conducted a prospective study of a cohort of 200 patients with moderate and severe infections. Moderate infections were subclassified after applying a previously published score. Variables associated with prognosis were: need for any amputation, major amputation, need for hospitalisation, length of hospitalisation, length of antibiotic therapy, reinfection rate and infection‐related mortality. Infections were moderate in 111 cases (55.5%) and severe in 89 (44.5%). Osteomyelitis (OM) was diagnosed in 114 cases (57%), 73 moderate (36.5%) and 41 severe (20.5%). Patients with severe OM had a higher rate of amputations, major amputations, hospitalisations and need for antibiotic therapy, and a longer duration of antibiotics when compared with moderate OM. After applying the score, moderate infections were subclassified into 73 moderate cases (65.7%) and 38 moderate/severe cases (34.3%). Moderate/severe had a higher rate of amputations, major amputations, hospitalisations and need for antibiotics than moderate ones. No differences regarding prognosis were found between moderate/severe and severe infections with systemic inflammatory response syndrome. Moderate/severe diabetic foot infections, which could also be known as severe infections without systemic inflammatory response syndrome, should be recognised as a new subgroup. We propose to merge severe diabetic foot infections with and without systemic inflammatory response syndrome into a unique category due to its prognostic value. Furthermore, OM should be added to both moderate and severe new categories of diabetic foot infections.