Antibiotic Therapy For Osteomyelitis Research Articles

Risk Factors and Characteristics of Recalcitrant Osteomyelitis Following Initial Surgical and Antibiotic Treatment.

To evaluate the injury, patient, and microbiological characteristics that place patients at risk for recalcitrant fracture related infection and osteomyelitis despite appropriate initial treatment. Retrospective Chart Review. Three level I trauma centers. Two hundred and fifty-seven patients undergoing surgical debridement and antibiotic therapy for osteomyelitis from 2003 to 2019. Patients were categorized as having undergone serial bone debridement if they had two separate procedures a minimum of six weeks apart with a full course of appropriate antibiotics in between. Patient records were reviewed for age, injury location, body mass index (BMI), smoking status, comorbidities, and culture results including the presence of multidrug resistant organisms (MDRO) and culture-negative osteomyelitis. A total of 257 patients were identified; 49% (n=125) had a successful single course of treatment, and 51% (n=132) required repeat debridement for recalcitrant osteomyelitis. At the index treatment for osteomyelitis, the most common organisms in both groups were Methicillin-resistant (MRSA) and Methicillin-sensitive Staphylococcus aureus (MSSA). There was no significant difference in incidence of polymicrobial infection between the two groups (25% vs 20%, p=0.49). The most common organisms cultured at the time of repeat saucerization remained MRSA and MSSA, however, the same organism was cultured from both the index and repeat procedure in only 28% (n=37) of cases. Diabetic patients, IVDU, delay to diagnosis, and open fractures of the lower leg are independent risk factors for failure of initial treatment of post-traumatic osteomyelitis. Successful eradication of fracture related infection and post-traumatic osteomyelitis is difficult and fails 51% of the time despite standard surgical and antimicrobial therapy. While MRSA and MSSA remain the most common organisms cultured, patients who fail initial treatment for osteomyelitis often do not culture the same organisms as those obtained at the index procedure.

Antibiotic Loaded Nano Rod Bone Cement for the Treatment of Osteomyelitis.

Polymethyl Methacrylate (PMMA) bone cement is the clinical gold standard biomaterial for local antibiotic therapy in osteomyelitis. However, it releases 50% of the antibiotic within the first three days. It generates excessive heat during polymerization and is non-biodegradable. It must be removed by another operation. The best-known alternative for PMMA is hydroxyapatite. The present patented work is focused on synthesizing the biodegradable hydroxyapatite in nano form for slow and sustained release of antibiotics and studying the release kinetics of antibiotics. Nano-hydroxyapatite was synthesized by co-precipitation method and characterized by particle size analyser, transmission electron microscopy, fourier transform infrared spectroscopy and energy dispersive X-Ray analysis. Antibiotic loaded nano-hydroxyapatite was prepared as 7 mm beads. The efficiency of drug-loaded nano-hydroxyapatite beads against osteomyelitic isolates was evaluated by well diffusion assay. Zero-order, first order, second order, Higuchi model, Korsmeyer-Peppas and Gompertz models were fit into the release kinetics of antibiotics from hydroxyapatite. Average size of nano-hydroxyapatite was 5 nm. The bactericidal activity exhibited by antibiotic- loaded micro-sized hydroxyapatite was therapeutic until 10 days only, whereas antibiotic-loaded nano-hydroxyapatite was therapeutic until 8 weeks. This confirms the burst release of antibiotics from micro-sized hydroxyapatite beads. In contrast, the release was slow and sustained up to 8 weeks from nano-hydroxyapatite. Korsmeyer-Peppas model fits into the release kinetics of antibiotics from nanohydroxyapatite. Nano-hydroxyapatite with a Ca/P ratio of 1.78 is suitable for the slow and sustained delivery of antibiotics for 8 weeks.

1431. Comparison of Treatment Outcomes with Definitive Antibiotic Therapy and Empiric Antibiotic Therapy in Osteomyelitis

BackgroundDefinitive therapy for osteomyelitis (OM) is thought to be superior to empiric antimicrobial therapy; however, identifying causative pathogens is difficult.MethodsThis retrospective cohort study included patients treated with either definitive or empiric antimicrobial therapy for OM at VA St. Louis HCS between 1 January 2010 and 1 January 2018. Definitive antibiotic therapy was defined as a regimen tailored to susceptibilities of an organism(s) cultured from bone or deep tissue. The primary outcome was treatment failure, defined as a need for unplanned surgical intervention or re-initiation of antibiotic therapy for OM of the same anatomical site within 6-months after initial therapy was discontinued. Secondary outcomes included the incidence of acute kidney injury (AKI), Clostridium difficile-associated diarrhea (CDAD), and thrombocytopenia. Surgical intervention as part of initial therapy, presence of peripheral vascular disease (PVD), creatinine clearance < 50 mL/minute at initiation of therapy, receiving antibiotics at an extended care facility, age > 60 years, and receiving definitive antibiotics were included in a univariate analysis with variables with a P < 0.2 included in a multivariate logistic regression.ResultsThere were 301 patients included; 179 in the definitive therapy group and 122 in the empiric therapy group. Baseline characteristics were similar among groups; however, more patients receiving definitive therapy had a bone biopsy compared with those treated with empiric therapy (58.1% (104/179) vs. 36.8% (45/122); P < 0.05). 33 percent (60/179) of patient treated with definitive therapy failed compared with 45% (55/122) treated with empiric therapy (P = 0.109). No significant differences were observed in secondary outcomes; however non-CDAD diarrhea occurred more in the empiric therapy group than definitive therapy group (3.9% (7/179) vs. 8.2% (10/122); P > 0.05). Receiving definitive therapy (OR 1.43, CI 0.89–2.313; P = 0.138) and presence of PVD (OR 1.34; CI 0.823–2.197; P = 0.238) were included in the multivariate logistic regression, but neither were independently associated with failure.ConclusionDefinitive antibiotic therapy was not associated with a significant decrease in treatment failure.Disclosures All authors: No reported disclosures.

Local Antibiotic Therapy in Osteomyelitis

The local delivery of antibiotics in the treatment of osteomyelitis has been used safely and effectively for decades. Multiple methods of drug delivery have been developed for the purposes of both infection treatment and prophylaxis. The mainstay of treatment in this application over the past 20 years has been non-biodegradable polymethylmethacrylate, which has the advantages of excellent elution characteristics and structural support properties. Biodegradable materials such as calcium sulfate and bone graft substitutes have been used more recently for this purpose. Other biodegradable implants, including synthetic polymers, are not yet approved for use but have demonstrated potential in laboratory investigations. Antibiotic-impregnated metal, a recent development, holds great promise in the treatment and prophylaxis of osteomyelitis in the years to come.

Organism isolation and serum bactericidal titers in oral antibiotic therapy for pediatric osteomyelitis.

Isolation of the etiologic organism and monitoring of serum bactericidal titers are considered necessary in oral antibiotic therapy for osteomyelitis. Over a 5-year period, 26 pediatric patients with hematogenous osteomyelitis were treated with sequential parenteraloral therapy. No organism was isolated in 9 cases, and bactericidal titers were determined in only 7 cases. All patients did well, raising questions about the conventional prerequisites invoked for oral treatment of skeletal infections.

Antibiotic Therapy for Osteomyelitis

Antibiotic therapy for osteomyelitis has dramatically changed within the past twenty years. The diagnostic criteria for osteomyelitis remain confusing to practicing physicians. Bone biopsy culture is now the standard for determining specific antimicrobial therapy. Many of the newest and most potent antimicrobials are now used to treat the increasingly broad bacterial spectrum of etiologies of osteomyelitis. There are tremendous economic incentives for outpatient and/or oral therapy. The third-generation cephalosporins and the new fluoroquinolones have replaced older, more toxic regimens, especially those containing aminoglycoside used to treat gram-negative osteomyelitis due to susceptible organisms.

Antibiotic Therapy in Osteomyelitis in Outpatients

The therapy of osteomyelitis utilizing 481 courses of intravenous antibiotics in outpatients was analyzed to identify the types of bone infection most frequently treated by this form of therapy. The efficacy of this form of treatment is also discussed.

In vivo studies of antibiotic therapy in osteomyelitis

In vivo studies of antibiotic therapy in osteomyelitis