Search Results
Lower-Extremity Osteomyelitis Treatment Using Calcium Sulfate/Hydroxyapatite Bone Void Filler with Antibiotics
Seven-Year Retrospective Study
Background:
Over a 74-month period (∼6 years), 143 lower-extremity osteomyelitis locations in 125 patients were treated with a calcium sulfate/hydroxyapatite liquid bone void filler with antibiotic(s).
Methods:
The osteomyelitis locations were treated with a percutaneous antibiotic delivery technique delivering intraosseous antibiotic followed by either oral or intravenous antibiotics for 4 weeks.
Results:
There was no recurrence of osteomyelitis in 96.15% of the treatable patients. Outcomes classified by the Cierny-Mader clinical classification are discussed as well.
Conclusions:
A bone void filler with antibiotic(s) using the percutaneous antibiotic delivery technique is a safe, reliable, and effective means to treat lower-extremity osteomyelitis with either oral or intravenous antibiotics for 4 weeks.
Background:
This study investigated the resistance of bacteria isolated from diabetic foot ulcers (DFUs) to antibiotics frequently used in the management of the diabetic foot infections, at a range of pH values (pH 6.5, 7.5, and 8.5) known to exist in DFU wound fluid. This study aimed to determine whether changes (or atypical stasis) in wound fluid pH modulate the antibiotic resistance of DFU isolates, with potential implications in relation to the suppression/eradication of bacterial infections in DFUs.
Methods:
Thirty bacterial isolates were recovered from DFU wound fluid, including Staphylococcus spp, Staphylococcus aureus, Escherichia coli, Streptococcus spp, Pseudomonas spp, and Pseudomonas aeruginosa. The resistances of these isolates to a panel of antibiotics currently used in the treatment of infected or potentially infected DFUs, ie, ciprofloxacin, amoxicillin-clavulanate, doxycycline, and piperacillin-tazobactam, at the previously mentioned pH values were determined by a modification of the Kirby-Bauer assay.
Results:
The resistance of DFU isolates to clinically relevant antibiotics was significantly affected by the pH levels in DFU wound fluid.
Conclusions:
These findings highlight the importance of a more comprehensive understanding of the conditions in DFUs to inform clinical decision making in the selection and application of antibiotics in treating these difficult-to-heal wounds. The scale of the differences in the efficacies of antibiotics at the different pH values examined is likely to be sufficient to suggest reconsideration of the antibiotics of choice in the treatment of DFU infection.
Background:
A percutaneous antibiotic delivery technique (PAD-T) used for the adjunctive management of osteomyelitis is presented.
Methods:
This surgical technique incorporates a calcium sulfate and hydroxyapatite (calcium phosphate) bone void filler acting as a carrier vehicle with either an antibiotic or an antifungal medicine, delivering this combination directly into the area of osteomyelitis.
Results:
The benefit of the PAD-T is reviewed with a case presentation of a successfully treated calcaneal osteomyelitis.
Conclusions:
No previously reported PAD-T using a simple bone cortex incision in the adjunctive treatment of osteomyelitis has been reported. The PAD-T safely and effectively uses a calcium sulfate and hydroxyapatite bone void filler carrier vehicle to deliver either an antibiotic or an antifungal medicine directly into the area of osteomyelitis.
Background: Several absorbable and nonabsorbable antibiotic carrier systems are available in the adjunctive surgical management of osteomyelitis of the foot, ankle, and lower leg. These carrier systems have significant limitations regarding which antibiotics can be successfully incorporated into the carrier vehicle. The calcium sulfate and hydroxyapatite Cerament Bone Void Filler is a biocompatible, absorbable ceramic bone void filler that can successfully deliver multiple heat-stable and heat-unstable antibiotics that have not been generally used before with antibiotic beads in treating musculoskeletal infections.
Methods: Cerament Bone Void Filler discs with the antibiotics rifampin, vancomycin, tobramycin, cefazolin, cefepime hydrochloride, vancomycin-tobramycin, piperacillin-tazobactam, ceftazidime, and ticarcillin-clavulanate were tested in vitro against methicillin-resistant Staphylococcus aureus.
Results: The zones of inhibition for the Cerament Bone Void Filler antibiotic discs plated against Staphylococcus aureus obtained were 33% to 222% greater than the minimum zones of inhibition breakpoints for bacteria susceptibility as defined by the standard set by the Clinical and Laboratory Standards Institute. Cerament Bone Void Filler discs with the antibiotics plated against Pseudomonas aeruginosa produced zones of inhibition of 93% to 200% greater than the minimum zones of inhibition breakpoints for bacteria susceptibility as defined by the standard set by the Clinical and Laboratory Standards Institute.
Conclusions: The calcium sulfate and hydroxyapatite Cerament Bone Void Filler was an excellent carrier vehicle for multiple antibiotics creating in vitro significant zones of inhibition, thus demonstrating susceptibility against Staphylococcus aureus and Pseudomonas aeruginosa, which holds tremendous promise in treating osteomyeilits. (J Am Podiatr Med Assoc 101(2): 146–152, 2011)
Pitted Keratolysis
A Clinical Review
Background
Pitted keratolysis is a bacterial infection that affects the plantar epidermis. Despite the condition being reported in many countries affecting both shod and unshod populations, there is little guidance for clinicians providing evidence or best practice guidelines on the management of this often stubborn infection.
Methods
Using a structured search of a range of databases, papers were identified that reported treatments tested on patients with the condition.
Results
Most of the literature uncovered was generally of a low level, such as case-based reporting or small case series. Studies were focused mainly on the use of topical antibiotic agents, such as clindamycin, erythromycin, fusidic acid, and mupirocin, often in combination with other measures, such as hygiene advice and the use of antiperspirants. From the limited evidence available, the use of topical antibiotic agents shows some efficacy in the treatment of pitted keratolysis. However, there is currently no suggestion that oral antibiotic drug therapy alone is effective in managing the condition.
Conclusions
Currently, there is no consensus on the most effective approach to managing pitted keratolysis, but a combination of antimicrobial agents and adjunctive measures, such as antiperspirants, seems to demonstrate the most effective approach from the current literature available.
Background
Diabetic foot infection (DFI) is a serious, difficult-to-treat infection, especially when caused by methicillin-resistant Staphylococcus aureus (MRSA). Vancomycin has been the standard treatment for MRSA infection, but lower response rates in MRSA skin infections have been reported. This analysis assessed the outcome and safety of daptomycin therapy in patients with a DFI caused by MRSA.
Methods
Using the Cubicin Outcomes Registry and Experience and the European Cubicin Outcomes Registry and Experience (2006–2009), 79 patients with MRSA DFI were identified and included in this analysis.
Results
In the 74 evaluable patients, daptomycin was administered at a median dose of 4.8 mg/kg primarily every 24 hours (85.1%) and for a median of 15.0 days. Overall, 77.0% of the patients (57 of 74) received initial therapy with activity against MRSA; however, of patients receiving daptomycin as second-line therapy (n = 31), only 45.2% were treated with an antibiotic agent active against MRSA. The overall clinical success and treatment failure rates were 89.2% and 10.8%, respectively. Success with daptomycin therapy was higher in patients who had surgery and in those whose initial therapy was daptomycin. Eleven patients had 14 adverse events, two of which were possibly related to daptomycin use and led to discontinuation.
Conclusions
In a large real-world cohort of patients with MRSA DFI, daptomycin therapy was shown to be generally well tolerated and effective. The use of an anti-MRSA antibiotic agent should be considered when implementing first-line antibiotic drug therapy for DFI in countries where MRSA is common to avoid inappropriate empirical treatment and potential negative effects on outcomes.
Background:
Below-the-knee amputation (BKA) can be a detrimental outcome of diabetic foot osteomyelitis (DFO). Ideal treatment of DFO is controversial, but studies suggest minor amputation reduces the risk of BKA. We evaluated risk factors for BKA after minor amputation for DFO.
Methods:
This is a retrospective cohort of patients discharged from Denver Health Medical Center from February 1, 2012, through December 31, 2014. Patients who underwent minor amputation for diagnosis of DFO were eligible for inclusion. The outcome evaluated was BKA in the 6 months after minor amputation.
Results:
Of 153 episodes with DFO that met the study criteria, 11 (7%) had BKA. Failure to heal surgical incision at 3 months (P < .001) and transmetatarsal amputation (P = .009) were associated with BKA in the 6 months after minor amputation. Peripheral vascular disease was associated with failure to heal but not with BKA (P = .009). Severe infection, bacteremia, hemoglobin A1c, and positive histopathologic margins of bone and soft tissue were not associated with BKA. The median antibiotic duration was 42 days for positive histopathologic bone resection margin (interquartile range, 32–47 days) and 16 days for negative margin (interquartile range, 8–29 days). Longer duration of antibiotics was not associated with lower risk of BKA.
Conclusions:
Patients who fail to heal amputation sites in 3 months or who have transmetatarsal amputation are at increased risk for BKA. Future studies should evaluate the impact of aggressive wound care or whether failure to heal is a marker of another variable.
Background
The preferred primary treatment of toe osteomyelitis in diabetic patients is controversial. We compared the outcome of primary nonoperative antibiotic treatment versus digital amputation in patients with diabetes-related chronic digital osteomyelitis.
Methods
We conducted a retrospective medical record review of patients treated for digital osteomyelitis at a single center. Patients were divided into two groups according to initial treatment: 1) nonoperative treatment with intravenous antibiotics and 2) amputation of the involved toe or ray. Duration of hospitalization, number of rehospitalizations, and rate of below- or above-the-knee major amputations were evaluated.
Results
The nonoperative group comprised 39 patients and the operative group included 21 patients. The mean ± SD total duration of hospitalization was 24.05 ± 15.43 and 20.67 ± 15.97 days, respectively (P = .43). The mean ± SD number of rehospitalizations after infection recurrence was 2.62 ± 1.63 and 1.67 ± 1.24, respectively (P = .02). During follow-up, the involved digit was eventually amputated in 13 of the 39 nonoperatively treated patients (33.3%). The rate of major amputation (above- or below-knee amputation was four of 39 (10.3%) and three of 21 (14.3%), respectively (P = .69).
Conclusions
Despite a higher rate of rehospitalizations and a high failure rate, in patients with mild and limited digital foot osteomyelitis in the absence of sepsis it may be reasonable to offer a primary nonoperative treatment for digital osteomyelitis of the foot.
Pseudomonas aeruginosa
An Uncommon Cause of Diabetic Foot Infection
Background
Pseudomonas aeruginosa has traditionally been considered a common pathogen in diabetic foot infection (DFI), yet the 2012 Infectious Diseases Society of America guideline for DFI states that “empiric therapy directed at P aeruginosa is usually unnecessary.” The objective of this study was to evaluate the frequency of P aeruginosa isolated from bone or tissue cultures from patients with DFI.
Methods
This study is a cross-sectional survey of diabetic patients presenting with a foot infection to an urban county hospital between July 1, 2012, and December 31, 2013. All of the patients had at least one debridement procedure during which tissue or bone cultures from operative or bedside debridements were obtained. The χ2 test and the t test of means were used to determine relationships between variables and the frequency of P aeruginosa in culture.
Results
The median number of bacteria isolated from DFI was two. Streptococcus spp and Staphylococcus aureus were the most commonly isolated organisms; P aeruginosa was isolated in only five of 112 patients (4.5%). The presence of P aeruginosa was not associated with the patient's age, glycosylated hemoglobin level, tobacco abuse, the presence of osteomyelitis, a prescription for antibiotic drugs in the preceding 3 months, or the type of operative procedure.
Conclusions
Pseudomonas aeruginosa was an infrequent isolate from DFI in this urban, underserved diabetic population. The presence of P aeruginosa was not associated with any measured risk factors. By introducing a clinical practice guideline, we hope to discourage frontline providers from using routine antipseudomonal antibiotic drugs for DFI.
Background
Regarding antibiotic-loaded cements, there is an abundant amount of literature regarding the antibacterial in vitro inhibitory and clinical applications for the treatment of osteomyelitis. The opposite can be said about literature regarding in vitro antifungal-loaded cement drug delivery for the treatment of fungal osteomyelitis.
Methods
Aspergillus fumigatus and Candida (ATCC 1023ATCC, Manassas, Virginia) were plated on antibiotic/antifungal-free plates. Voriconazole- and amphotericin B–impregnated calcium sulfate and hydroxyapatite (HA) disks, calcium sulfate + HA control disks, and control polymethylmethacrylate disks were laid separately onto plates separately inoculated with Aspergillus and Candida spp. The zones of inhibition obtained were measured in millimeters at 24, 36, and 96 hours.
Results
Etest (bioMérieux, Marcy l'Etoile, France) results demonstrated susceptibility of Aspergillus and Candida to amphotericin B and voriconazole. The zone of inhibition data demonstrated that voriconazole and amphotericin B retained their antifungal activity when mixed into the calcium sulfate + HA bone void filler and eluted at biologically effective antifungal concentrations over 96 hours.
Conclusions
The calcium sulfate + HA bone void filler is a biocompatible ceramic carrier vehicle that can successfully deliver the antifungal drugs voriconazole and amphotericin B in the adjunctive treatment of fungal osteomyelitis. It is a reliable strategy in the local delivery of antifungal drugs to an area of osteomyelitis.
