Osteoarticular infections: a specific program for older patients?

Perioperative Urinary Catheter Use and Association to (Gram-Negative) Surgical Site Infection after Spine Surgery

This study evaluates potential associations between the perioperative urinary catheter (UC) carriage and (Gram-negative) surgical site infections (SSIs) after spine surgery. It is a retrospective, single-center, case-control study stratifying group comparisons, case-mix adjustments using multivariate logistic regression analyses. Around half of the patients (2734/5485 surgeries) carried a UC for 1 day (median duration) (interquartile range, 1-1 days). Patients with perioperative UC carriage were compared to those without regarding SSI, in general, and Gram-negative, exclusively. The SSI rate was 1.2% (67/5485), yielding 67 revision surgeries. Gram-negative pathogens caused 16 SSIs. Seven Gram-negative episodes revealed the same pathogen concomitantly in the urine and the spine. In the multivariate analysis, the UC carriage duration was associated with SSI (OR 1.1, 95% confidence interval 1.1-1.1), albeit less than classical risk factors like diabetes (OR 2.2, 95%CI 1.1-4.2), smoking (OR 2.4, 95%CI 1.4-4.3), or higher ASA-Scores (OR 2.3, 95%CI 1.4-3.6). In the second multivariate analysis targeting Gram-negative SSIs, the female sex (OR 3.8, 95%CI 1.4-10.6) and a UC carriage > 1 day (OR 5.5, 95%CI 1.5-20.3) were associated with Gram-negative SSIs. Gram-negative SSIs after spine surgery seem associated with perioperative UC carriage, especially in women. Other SSI risk factors are diabetes, smoking, and higher ASA scores.

The Epidemiology of Antibiotic-Related Adverse Events in the Treatment of Diabetic Foot Infections: A Narrative Review of the Literature

The use of antibiotics for the treatment of diabetic foot infections (DFIs) over an extended period of time has been shown to be associated with adverse events (AEs), whereas interactions with concomitant patient medications must also be considered. The objective of this narrative review was to summarize the most frequent and most severe AEs reported in prospective trials and observational studies at the global level in DFI. Gastrointestinal intolerances were the most frequent AEs, from 5% to 22% among all therapies; this was more common when prolonged antibiotic administration was combined with oral beta-lactam or clindamycin or a higher dose of tetracyclines. The proportion of symptomatic colitis due to Clostridium difficile was variable depending on the antibiotic used (0.5% to 8%). Noteworthy serious AEs included hepatotoxicity due to beta-lactams (5% to 17%) or quinolones (3%); cytopenia's related to linezolid (5%) and beta-lactams (6%); nausea under rifampicin, and renal failure under cotrimoxazole. Skin rash was found to rarely occur and was commonly associated with the use of penicillins or cotrimoxazole. AEs from prolonged antibiotic use in patients with DFI are costly in terms of longer hospitalization or additional monitoring care and can trigger additional investigations. The best way to prevent AEs is to keep the duration of antibiotic treatment short and with the lowest dose clinically necessary.

Timing of Revascularization and Parenteral Antibiotic Treatment Associated with Therapeutic Failures in Ischemic Diabetic Foot Infections

For ischemic diabetic foot infections (DFIs), revascularization ideally occurs before surgery, while a parenteral antibiotic treatment could be more efficacious than oral agents. In our tertiary center, we investigated the effects of the sequence between revascularization and surgery (emphasizing the perioperative period of 2 weeks before and after surgery), and the influence of administering parenteral antibiotic therapy on the outcomes of DFIs. Among 838 ischemic DFIs with moderate-to-severe symptomatic peripheral arterial disease, we revascularized 608 (72%; 562 angioplasties, 62 vascular surgeries) and surgically debrided all. The median length of postsurgical antibiotic therapy was 21 days (given parenterally for the initial 7 days). The median time delay between revascularization and debridement surgery was 7 days. During the long-term follow-up, treatment failed and required reoperation in 182 DFI episodes (30%). By multivariate Cox regression analyses, neither a delay between surgery and angioplasty (hazard ratio 1.0, 95% confidence interval 1.0–1.0), nor the postsurgical sequence of angioplasty (HR 0.9, 95% CI 0.5–1.8), nor long-duration parenteral antibiotic therapy (HR 1.0, 95% CI 0.9–1.1) prevented failures. Our results might indicate the feasibility of a more practical approach to ischemic DFIs in terms of timing of vascularization and more oral antibiotic use.

Outpatient Parenteral Antibiotic Therapy in Older Adults

Outpatient parenteral antimicrobial therapy (OPAT) for older adults is a complex process that involves multiple stakeholders and care coordination, but it is a useful and patient-centered tool with opportunities for the treatment of complicated infections, improved patient satisfaction, and reduced health-care costs. Older age should not be an exclusion for OPAT but rather prompt the OPAT provider to thoroughly evaluate candidacy and safety. Amid the on-going COVID-19 pandemic, innovations in OPAT are needed to shepherd OPAT care into a more patient-centered, thoughtful practice, whereas minimizing harm to older patients from unnecessary health-care exposure and thus health-care associated infections.

Clinical Features, Inflammatory Markers, and Limb Salvage in Older Adults with Diabetes-Related Foot Infections

Little information exists about diabetic foot infections (DFIs) in older patients. We hypothesize that older patients with DFIs have different clinical features and worse outcomes than younger patients. We conducted a prospective observational study consisting of a cohort of patients with diabetes and moderate to severe DFIs. Patients included in the cohort were dichotomized into two groups using percentile 75 (P75) of age as the cut-off value. Patients aged > P75 presented with more comorbidities and foot-related complications, a higher rate of peripheral arterial disease (PAD), worse renal function (higher values of blood urea nitrogen and creatinine, and lower values of estimated glomerular filtration rate), and lower values of HbA1c compared with younger patients. Infection severity, microbiological features, and inflammatory markers were similar in both groups. In the multivariate analysis, minor amputations were associated with age > P75 (OR = 2.8, 95% CI 1.3-5.9, p <0.01), necrosis (OR = 4.2, 95% CI 1.8-10.1, p < 0.01), and CRP values (OR = 1.045, 95% CI 1.018-1.073, p < 0.01). Major amputations were associated with a history of amputation (OR = 4.7, 95% CI 1.3-16.7, p = 0.01), PAD (OR = 4.3, 95% CI 1.2-14.6, p = 0.01), and albumin values (OR = 0.344, 95% CI 0.130-0.913, p = 0.03). In conclusion, limb salvage can be achieved in older patients with diabetes-related foot infections at the same rate as in younger patients, despite the fact that they have more comorbidities and foot-related complications, a higher rate of PAD, and worse renal function.

Model-Informed Precision Dosing of Antibiotics in Osteoarticular Infections

As a heterogeneous and wide inflammation, osteoarticular infection (OAI) shows an increasing incidence in recent years. Staphylococcus aureus is the most important pathogen causing OAI. The antibiotic treatment will affect the outcomes of OAI patients, and the drug selection and dosage regimen highly rely on patients' variability, pathogen susceptibility, and drug property like bone permeability. Model-informed precision dosing (MIPD) provides options to describe and quantify the pharmacokinetic (PK) variability of the OAI population using different models, such as the population pharmacokinetic (PPK) model and physiological-based pharmacokinetic (PB/PK) model. In the present review, we highlighted that the MIPD of antibiotics played a critical role in OAI and listed the dose regimen recommended by the model. Collectively, our current study provided a valuable reference for the treatment of patients and improved the safety and efficiency of drug use.

Nutritional Interventions May Improve Outcomes of Patients Operated on for Diabetic Foot Infections: A Single-Center Case-Control Study

AIM

While a patient's nutritional status is known to generally have a role in postoperative wound healing, there is little information on its role as therapy in the multifaceted problem of diabetic foot infections (DFIs).

METHODS

We assessed this issue by conducting a retrospective case-control cohort study using a multivariate Cox regression model. The nutrition status of the DFI patients was assessed by professional nutritionists, who also orchestrated the nutritional intervention (counselling, composition of the intrahospital food) during hospitalization.

RESULTS

Among 1,013 DFI episodes in 586 patients (median age 67 years; 882 with osteomyelitis), 191 (19%) received a professional assessment of their nutrition accompanied by between 1 and 6 nutritional interventions. DFI cases who had professional nutritionists' interventions had a significantly shorter hospital stay, had shorter antibiotic therapies, and tended to fewer surgical debridements. By multivariate analysis, episodes with low Nutritional Risk Status- (NRS-) Scores 1-3 were associated with significantly lower failure rates after therapy for DFI (Cox regression analysis; hazard ratio 0.2, 95% confidence interval 0.1-0.7).

CONCLUSIONS

In this retrospective cohort study, DFI episodes with low NRS-Score were associated with lower rates of clinical failure after DFI treatment, while nutritional interventions improved the outcome of DFI. We need prospective interventional trials for this treatment, and these are underway.

Usefulness of therapeutic drug monitoring in estimating the duration of dalbavancin optimal target attainment in staphylococcal osteoarticular infections: a proof-of-concept

Dalbavancin is increasingly used for the treatment of staphylococcal osteoarticular infections (OIs). Some population pharmacokinetic studies suggest that a regimen of two 1500 mg doses 1 week apart could ensure effective treatment for several weeks. Here we aim to provide clinicians with a proof-of-concept of the potential role that therapeutic drug monitoring may have in giving real-time feedback of the estimated duration of optimal treatment of staphylococcal OIs with dalbavancin in each single patient.