Antibiotic Beads Research Articles

Isolation and purification of lactic acid bacteria and yeasts based on a multi-channel magnetic flow device and rapid qualitative and quantitative detection

Rapid isolation and identification of lactic acid bacteria and yeasts during fermentation is of great significance for quality control and regulation of fermented foods. In this study, we prepared a multi-channel magnetic flow device for rapid separation and purification of lactic acid bacteria and yeast, and based on SERS spectrum, we made rapid qualitative and quantitative analysis of Lactobacillus plantarum, Lactococcus lactis and Saccharomyces cerevisiae. The results showed that the synthesized Synthesized Fe3O4-Van antibiotic magnetic beads are paramagnetic; Fe3O4-Van antibiotic magnetic beads achieved capture efficiencies of more than 98.5 % for both L. plantarum and L. lactis at 102–104 CFU/mL, respectively. Separation and purification efficiency of single S. cerevisiae, L. plantarum and L. lactis by multi-channel magnetic flow device all reached more than 98 % with good isolation and purification results. The SERS spectra of the three microorganisms were classified and analyzed using linear discriminant analysis (LDA), and the accuracy of the established LDA model was 100 %, which completely differentiated the SERS spectra of the three microorganisms,and realized the qualitative identification of L. plantarum, L. lactis, and S. cerevisiae, and finally, quantitative model was established with the logarithmic values (lg C) of different concentrations of L. plantarum, L. lactis, and S. cerevisiae as the horizontal coordinates, and the Raman intensities at their strongest characteristic peaks of 512 cm−1, 1669 cm−1, and 1125 cm−1, respectively, were used as vertical coordinates to establish a quantitative model, with the lowest detection limit of 10 CFU/mL, and the digital quantification of lactic acid bacteria and yeast were achieved. It provided an effective means for real-time monitoring and tracking of the dynamics of lactic acid bacteria and yeast in the fermentation process and the quality control of fermented foods.

Use of local treatment in managing infections: Focus on antimicrobial locks, beads, and cement.

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. The purpose of this review is to describe important considerations with local antimicrobial therapies such as locks, beads, and cement for adjunctive infection management or prevention. Local delivery of antimicrobials with locks, beads, and cement has been used for infection management with retained devices in an effort to improve clinical success. However, their use has been controversial due to conflicting clinical data and logistical issues. Antimicrobial lock therapy (ALT) has been used for both adjunctive treatment and prevention of catheter-related bloodstream infections for certain pathogens and based on patient-specific scenarios. ALT has been a controversial method for sterilizing the catheter lumen by delivering high concentrations of antibiotics with or without heparin into the catheter for prolonged durations. Studies differ regarding the selection and concentrations of antibiotics, dwell duration, presence of heparin in the ALT, clinical outcomes/definitions, and use for prevention or treatment of catheter-related bloodstream infections. Antibiotic beads and cement have been used for various surgical procedures but are predominately considered in orthopedic surgeries. Despite the widespread use of the antibiotic-loaded bone cement in orthopedics, studies differ regarding the selection and concentrations of antibiotics, clinical outcomes/definitions, and use for prevention or treatment of infections. Although antimicrobial locks, beads, and cement are commonly used for adjunctive treatment or prevention of infections, more data are needed to support their use to provide clinical efficacy and safety with consistent antimicrobial selection and logistics.

Polymeric Antibiotic Beads for Canine Osteomyelitis: Advancing Localized Antibiotic Treatment with Enhanced Efficacy and Minimized Side Effects

Antibiotic beads represent a compelling treatment method for the treatment and prevention of canine osteomyelitis, as they provide localized antibiotic concentrations at the infection site with minimal systemic toxicity. The therapeutic efficacy of these beads has been demonstrated, highlighting their potential as a valuable local antibiotic therapy. In particular, the introduction of vancomycin - polymethylmethacrylate (PMMA) beads is highlighted as a promising new form of local antibiotic therapy. This article focuses on the use of antibiotic-impregnated beads to treat localized bacterial infections in the bones and joints of canines. Typically composed of poly(lactic-co-glycolic acid) (PLGA) or polymethylmethacrylate (PMMA), these beads contain antibiotics such as vancomycin, placed directly into the affected area, providing a high antibiotic concentration at the site of infection. These beads were developed for a slow antibiotic release over time; they ensure a constant protective effect against a broad spectrum of bacteria, demonstrating high efficacy and biocompatibility with the animal's body. This localized antibiotic treatment option offers several advantages over systemic antibiotics, such as reduced side effects and improved efficacy. It could be a promising option for the treatment of bone and joint infections in canines.

Development of a Biodegradable PLGA Carrier to Provide Wnt Agonists and Antibiotics to Meet the Requirements for Patients with Bone Infections.

Antibiotic beads can be used to treat surgical infections. In this study, polylactide-polyglycolide (PLGA) was mixed with vancomycin, the osteogenic enhancer lithium chloride (LiCl), and hot compression to form PLGA-vancomycin-LiCl delivery beads to treat bone infection. An elution method was used to characterize in vitro release characteristics of vancomycin and Li over a 42-day period. The release profiles lasted for more than 42 days for vancomycin and 28 days for Li. The concentration of vancomycin in each sample was well above the breakpoint sensitivity. Lithium cotreatment enhanced the bactericidal effect of vancomycin. Released Li and vancomycin increased the mRNA or protein expressions of osteogenic markers of mesenchymal stem cells (MSCs). In vivo, the PLGA delivery systems were implanted into the distal femoral cavities of rabbits, and the cavity fluid content was aspirated and analyzed at each time point. The released Li and vancomycin lasted more than 6 weeks, and the vancomycin concentrations were much greater than the breakpoint sensitivity. Four rabbits in each group were sacrificed at 8 weeks for histological observation. More mature bone tissue was observed in the Li treatment group. This study provides a PLGA drug delivery system to meet the requirements of patients with bone infections.

In vitro elution of amikacin, cefazolin, gentamicin, ampicillin/sulbactam, and meropenem from a commercially available calcium sulfate delivery kit.

The use of implantable antibiotic beads has become a frequent treatment modality for the management of surgical site infections in human and veterinary medicine. The objective of this study is to describe the elution kinetics of five antibiotics from a commercially available calcium sulfate antibiotic delivery kit. A secondary goal was to compare elution concentrations with minimal inhibitory concentrations (MIC) for commonly encountered bacteria from the University of Florida's veterinary microbiology laboratory database. Calcium sulfate powder was combined with amikacin, cefazolin, gentamicin, ampicillin/sulbactam, and meropenem. Triplicates of three antibiotic-loaded beads were immersed in 5 mL of phosphate-buffered saline (PBS) and kept at 37°C under constant agitation. Antibiotic-conditioned PBS was sampled at 14 time points from 1-h to 30 days and analyzed by liquid chromatography to determine the antibiotic concentration. All beads eluted concentrations of antibiotics for the 30-day sampling period, except for ampicillin/sulbactam, with the most antibiotics being eluted within the first week. The concentration of antibiotics within the eluent within the first 3-9 days (3- and 5-mm beads, respectively) was greater than the MIC of common isolates. The 5 mm bead samples were superior in maintaining higher concentrations for a longer period, compared to the 3-mm beads. CSH beads eluted antibiotics over the 30-day course of the study. Most of the antibiotic elution occurred within the first week and was maintained above the MIC of commonly encountered isolates. This information may be useful for clinical decision making for treatment of local infections encountered in practice.

Enhancing Outcomes in Prosthetic Joint Infections: The Significance of the Periprosthetic Joint Infection Tumor, Node, and Metastasis (PJI-TNM) Classification and Biodegradable Antibiotic Beads.

Periprosthetic joint infections (PJIs) that occur after hip and knee arthroplasty have a major influence on patient outcomes and healthcare expenses. This study assesses the effectiveness of the PJI tumor, node, and metastasis (PJI-TNM) categorization system and the latest developments in local antibiotic delivery methods for the treatment of PJIs. The study involved a retrospective analysis of 23 patients who received treatment for septic hip or knee prostheses at the SUUB Orthopedics and Traumatology Clinic between January 1, 2022, and February 10, 2024. Approval was gained following ethical considerations. Patients were categorized using the PJI-TNM system, and their therapy was customized based on the severity of the infection. The surgical procedures involved either one-stage or two-stage revisions, utilizing vancomycin and gentamicin antibiotic-loaded calcium sulfate beads to administer antibiotics locally. Data pertaining to demographics, clinical characteristics, and microbiology were gathered and examined. The study comprised 14 male and 9 female patients, with an average age of 68 years. The presence of chronic infections was mostly seen, indicating the development of mature biofilm. Prevalent coexisting medical conditions included diabetes, obesity, and heart failure. The duration of infection control measures was, on average, six months, and 65% of patients reported experiencing enhanced mobility. Acute infections with positive antibiotic responses underwent one-stage modifications. For the majority of patients, a treatment approach involving two-stage modifications, which includes the use of antibiotic-loaded spacers followed by the installation of a prosthesis, proved to be beneficial. The PJI-TNM classification system improves the management of PJI by offering a systematic method for customized therapy. Calcium sulfate beads, which are biodegradable carriers for antibiotics, provide notable advantages, especially for individuals with severe comorbidities. Continuous progress in diagnostic techniques and localized administration of antibiotics is essential for enhancing the therapy of PJI and improving patient outcomes.

Prophylactic absorbable antibiotic beads for prepectoral implant-based breast reconstruction: A single institution early experience

Infection after implant-based breast reconstruction remains challenging, with infection rates up to 24%. Best clinical practice indicates prophylactic oral antibiotics are ineffective at preventing infection. Absorbable antibiotic beads have been routinely used in other surgical subspecialties such as orthopedic and vascular procedures for continuous local antibiotic delivery to the surgical site when implants are placed. Biodegradable calcium sulfate antibiotic beads have been shown to normalize incidence of infection when used prophylactically for a high-risk prepectoral patient population. The purpose of this study is to evaluate the effect of prophylactic biodegradable antibiotic beads when used non-selectively for all prepectoral immediate tissue expander (TE) reconstruction. Patients who underwent mastectomy and immediate prepectoral TE reconstruction on the same day between 2018 and 2024 were reviewed. Patients were divided into two groups: those who received antibiotic beads (Group 1) and those who did not (Group 2). Absorbable calcium-sulfate beads were reconstituted with 1g vancomycin and 240mg gentamicin. There were 33 patients (63 TEs) in Group 1 and 330 patients (545 TEs) in Group 2. TE loss was present in 1.5% (1/65 TEs) Group 1 compared to 9.4% (51/545 TEs) in Group 2 (p=0.032). The mean follow-up time was 178 days (range 93-266 days). Prophylactic biodegradable antibiotic beads used during immediate tissue expander reconstruction decreased implant loss rate. There was one occurrence of SSI in the antibiotic bead group. Antibiotic beads may potentially decrease complications in immediate TE reconstruction when used non-selectively for all patients.

Comparative outcome of usage of stimulan vs antibiotic beads in chronic long standing infections

Comparative outcome of usage of stimulan vs antibiotic beads in chronic long standing infections

Functional outcome of chronic osteomyelitis treated by sequestrectomy & saucerisation with antibiotic bead implantation

Functional outcome of chronic osteomyelitis treated by sequestrectomy & saucerisation with antibiotic bead implantation

Antibiotic calcium sulphate beads lower the bacterial burden and prevent infection in a mouse model of periprosthetic joint infection.

Delayed postoperative inoculation of orthopaedic implants with persistent wound drainage or bacterial seeding of a haematoma can result in periprosthetic joint infection (PJI). The aim of this in vivo study was to compare the efficacy of vancomycin powder with vancomycin-eluting calcium sulphate beads in preventing PJI due to delayed inoculation. A mouse model of PJI of the knee was used. Mice were randomized into groups with intervention at the time of surgery (postoperative day (POD) 0): a sterile control (SC; n = 6); infected control (IC; n = 15); systemic vancomycin (SV; n = 9); vancomycin powder (VP; n = 21); and vancomycin bead (VB; n = 19) groups. Delayed inoculation was introduced during an arthrotomy on POD 7 with 1 × 105 colony-forming units (CFUs) of a bioluminescent strain of Staphylococcus aureus. The bacterial burden was monitored using bioluminescence in vivo. All mice were killed on POD 21. Implants and soft-tissue were harvested and sonicated for analysis of the CFUs. The mean in vivo bioluminescence in the VB group was significantly lower on POD 8 and POD 10 compared with the other groups. There was a significant 1.3-log10 (95%) and 1.5-log10 (97%) reduction in mean soft-tissue CFUs in the VB group compared with the VP and IC groups (3.6 × 103 vs 7.0 × 104; p = 0.022; 3.6 × 103 vs 1.0 × 105; p = 0.007, respectively) at POD 21. There was a significant 1.6-log10 (98%) reduction in mean implant CFUs in the VB group compared with the IC group (1.3 × 100 vs 4.7 × 101, respectively; p = 0.038). Combined soft-tissue and implant infection was prevented in 10 of 19 mice (53%) in the VB group as opposed to 5 of 21 (24%) in the VP group, 3 of 15 (20%) in the IC group, and 0% in the SV group. In our in vivo mouse model, antibiotic-releasing calcium sulphate beads appeared to outperform vancomycin powder alone in lowering the bacterial burden and preventing soft-tissue and implant infections.

In vitro analysis of various antibiotic and cement combinations against S. epidermidis and S. lugdunensis for treatment of periprosthetic shoulder infection

BackgroundPeriprosthetic joint infections (PJIs) are devastating potential complications after arthroplasty surgery with significant therapeutic challenges. Many authors advocate for two-stage revision arthroplasty for PJI of the shoulder which includes explanation with antibiotic spacer placement. The optimal antibiotic/cement combination for PJI in the shoulder is not known. The purpose of this study is to analyze various cement and antibiotic concentrations against Coagulase negative staphylococcus species, S. epidermidis and S. lugdunensis. MethodsFive strains of coagulase negative Staph were taken from clinically documented orthopedic infections Both Simplex and Palacos cement were used to create antibiotic laden beads and mixed with either ertapenem, vancomycin, gentamicin, or a combination of ertapenem + vancomycin or ertapenem + gentamicin. The bacteria were plated on lysogeny broth agar plates and 3 beads were added per plate. Samples were analyzed for zone of inhibition at 24 hours, 72 hours, and 1 week. After 1 week, beads were transferred to new plates with bacteria and the process was repeated for 6 weeks. ResultsResults showed that ertapenem beads with both Simplex and Palacos cement showed the largest zones of inhibition for all samples. Vancomycin in Palacos cement and vancomycin in combination with ertapenem in Simplex and Palacos cement showed consistent zones of inhibition for the duration of the experiments. Ertapenem in combination with either vancomycin or gentamicin may allow for a powerful initial burst of killing followed by consistent antibiotic elution as opposed to gentamicin alone. ConclusionWhile many premade spacers on the market are infused with gentamicin, our in vitro models demonstrate more efficacious bacterial eradication for antibiotics such as ertapenem and vancomycin specifically for certain low virulence organisms that are commonly found in PJI around the shoulder.

Role of STIMULAN in chronic osteomyelitis-A randomised blinded study on 95 patients comparing 3 antibiotic compositions, bead quality, forming & absorption time

IntroductionChronic Osteomyelitis is a well-known clinical entity affecting patients holistically and presents with multiple treatment challenges. Local antibiotic delivery with biodegradable drug carriers has shown promising results. Materials and methodsProspective multicenter study performed at 2 centers from November 2021 to January 2023 on 95 osteomyelitis patients treated with surgical debridement & STIMULAN™ for local antibiotic delivery. Patients were randomized into 3 groups. Authors compared antibiotic combinations, bead quality, bead setting, and resorption time for calcium sulfate beads- STIMULAN™. Additionally, organisms isolated, WBC Turnover time, Hypersensitivity Reactions, Recurrence, and Revision Rates were documented. Results95 patients underwent surgical debridement and STIMULAN™ bead application for chronic osteomyelitis. The proximal 1/3rd tibia was commonly affected. The most common symptoms were sinus and pus discharge in 96.84 % & 86.31 % of patients respectively (p < 0.001). Staphylococcus aureus & MRSA were isolated in 37.8 % & 29.4 % of the patient's wound culture respectively. Bead setting time in Descending order was Group 3 > Group 2 > Group 1 (p < 0.001). Bead setting first in Group 1 followed by Group 3 & 2. On compression, Group-1 beads withstood maximum compression forces & had smooth even bead surfaces. On radiographs, 1/3rd bead volume in ascending order was Group 3 > Group 2 > Group 1 (p < 0.001). 2/3rd reduction in ascending order was Group 3 > Group 2 > Group 1. Complete bead absorption was earliest seen in Group 3 followed by Group 2 & Group 1 (p < 0.001). Recurrence in 2 patients (Group 2) at 6 weeks. Revision rate: 2.10 %. There were no incidences of hypersensitivity. Suture removal was done at 16 ± 2 days. ConclusionSTIMULAN™ combination with tobramycin, vancomycin, and gentamycin is stable, and forms uniform beads with predictable drug elution & bead resorption with negligible side effects. A mixture with higher liquid content sets later, forms softer beads, and resorbs earlier.

Successful use of platelet-rich plasma as a regeneration technique for a non-healing diabetic leg ulcer with chronic osteomyelitis: A case report

Chronic diabetic leg ulcers can be challenging to manage, particularly when osteomyelitis coexists resulting in serious or even life-threatening conditions if not managed appropriately. Such cases require very long periods of treatment with several debridements, antibiotic bead implants, skin grafts or even amputations in many unfortunate cases. Despite that, conventional management appears to be inadequate with poor outcomes and a higher relapse rate. We report a case of a 26-year-old type 1 diabetic female patient presented with a history of non-healing diabetic leg ulcer complicated by chronic osteomyelitis of the left leg. Several wound debridements were performed with the application of vacuum-assisted closure, and culture-guided antibiotics were given. However, only minimal improvements were observed. Eventually, the leg was labeled as an unsalvagable limb due to poor blood supply based on an ankle-brachial index. Platelet-rich plasma (PRP) was tried showing promising results and significant improvement as confirmed by a gallium scan, which showed evidence of osteomyelitis remission. Two months later, the patient improved significantly with the ulcer healed and the osteomyelitis resolved. Autologous PRP promotes wound healing by providing necessary growth factors, reducing inflammation, and showing bactericidal activity. All efforts must be taken to preserve any limb before labeling it non-salvageable. This case report aimed to draw attention to the method that can be implemented to manage non-healing diabetic leg ulcers complicated by chronic osteomyelitis.

Are Biodegradable Calcium Sulfate Antibiotic Beads Effective and Safe Adjuvants for Diabetic Foot Osteomyelitis?

Diabetic foot osteomyelitis (DFO) is a highly morbid condition that commonly affects diabetic patients. Biodegradable calcium-sulfate antibiotic beads (CaSO4) are theoretical adjuvant agents to reduce morbidity in DFO. However, there is a paucity of research on the safety and effectiveness of CaSO4 beads in DFO.Therefore, the purpose of this study was to assess the safety and effectiveness of CaSO4 beads in different DFO locations. We conducted a retrospective cohort study between January 1, 2015 and January 1, 2022 of patients with DFO who underwent surgical intervention and adjuvant CaSO4 beads placement.The location of DFO was determined based on the forefoot, midfoot, or hindfoot locations.Outcomes measured were ulcer-free time points of three and six months as well as recurrence of DFO at 12 months.Safety was also evaluated with incidences of acute kidney injury, wound drainage, and hypercalcemia. Forty-five cases were included. Of these, only 9/45 (20%) and 13/45 (29%) were ulcer-free at three months and six months, respectively.DFO recurred in 19/45 (42%) patients.Safety outcomes were significant for wound drainage (62%) and acute kidney injury (9%).Stratifying according to the location of DFO showed no statistically significant difference in outcomes. In this cohort study, adjuvant CaSO4 beads showed high rates of ulcer persistence and DFO recurrence. Given the limited benefits seen here and the potential for high rates of wound drainage, the use of adjuvant CaSO4 beads should be used cautiously until a multicenter randomized clinical trial is conducted to definitely evaluate the safety and effectiveness of CaSO4 beads in DFO.

Bone reconstruction with modified Masquelet technique in open distal femoral fractures: a case series.

Large bone defects require complex treatment, multidisciplinary resources, and expert input, with surgical procedures ranging from reconstruction and salvage to amputation. The aim of this study was to provide the results of a case series of open comminuted intra-articular distal femoral fractures with significant bone loss that were managed by early fixation using anatomical plates and a modified Masquelet technique with the addition of surgical propylene mesh. This retrospective study included all patients referred to our institution with OTA/AO C3 distal femur open fractures and meta-diaphyseal large bone loss between April 2019 and February 2021. We treated the fractures with irrigation and debridement, acute primary screw and plate fixation in the second look operation, and Masquelet method using shell-shaped antibiotic beads supplemented by propylene surgical mesh to keep the cements in place. The second step of the procedure was conducted six to eight weeks later with bone grafting and mesh augmentation to contain bone grafts. Surprisingly, hard callus formation was observed in all patients at the time of the second stage of Masquelet procedure. All five patients' articular and meta-diaphyseal fractures with bone loss healed without major complications. The average union time was 159 days. The mean knee range of motion was 5-95 degrees. The average Lower Extremity Functional Score (LEFS) was 49 out of 80. Combination of early plate fixation and the modified Masquelet technique with polypropylene mesh is an effective method for managing large bone defects in open intra-articular distal femoral fractures with bone loss, resulting in shorter union time possibly associated with the callus formation process. This technique may also be applicable to the management of other similar fractures specially in low-income and developing areas.

A Modified Technique for Two-Stage Revision in Knee PJI Treatment

Knee PJIs represent one of the most important complications after joint replacement surgery. If the prerequisites for implant retention do not subsist, the surgical treatment of these conditions is performed using one-stage and two-stage revision techniques. In this study, an implemented two-stage revision technique was performed, adopting antibiotic calcium sulfate beads and tumor-like debridement guided by methylene blue, such as described for the DAPRI technique. The aim of the present study is to compare the implemented two-stage revision technique with the standard technique in order to assess its effectiveness. Methods. Twenty patients affected by knee PJIs were prospectively enrolled in the study and underwent an implemented two-stage revision technique (Group A). Data collected and clinical results were compared with a matched control group treated with a standard two-stage technique (Group B). For each patient, the time of the reimplantation and length of antibiotic systemic therapy were recorded. Each patient underwent routine laboratory tests, including inflammatory markers. Results. In Group A and in Group B, inflammatory markers normalized at 6.5 ± 1.1. weeks and 11.1 ± 2.3 weeks, respectively (p &lt; 0.05). Also, the difference in length of antibiotic therapy and time to reimplantation were significantly shorter in Group A (p &lt; 0.05). No recurrence of infection was found in Group A at the last follow-up. Discussion. The implemented two-stage revision technique demonstrated a faster normalization of inflammatory markers, as well as a decrease in reimplantation time and duration of antibiotic therapy, compared to the traditional technique. The use of calcium sulfate antibiotic beads and tumor-like debridement seems to improve the results and reduce the time of healing. Conclusion. The implemented two-stage revision technique seems to improve the results and reduce the time of healing. This leads to a more rapid and less stressful course for the patient, as well as a reduction in health care costs.

Management of segmental defects post open distal femur fracture using a titanium cage combined with the Masquelet technique A single-centre report of 23 cases

IntroductionThe segmental bone defects post open distal femur fracture presents a reconstructive challenge, which often requires extreme solutions. The present study reviewed a new treatment strategy which used a cylindrical titanium mesh cage as an adjunct to the Masquelet technique. MethodsWe retrospectively reviewed a consecutive series of 23 patients treated for segmental bone defects post open distal femur fracture using a titanium mesh cage combined with the Masquelet technique under a 2-staged protocol in our institution from 2017 to 2021. The study group consisted of 13 men and 10 women with an average age of 44.1 years. The surgical debridement was performed with antibiotic polymethylmethacrylate (PMMA) cement spacer implanted into the bone defect combined with cement-wrapped plate stabilization, or antibiotic beads with vacuum sealing drainage (VSD) to cover the wound. The second stage of the Masquelet technique for bone defect repair began at least 4–6 weeks after the first stage, once all signs of possible infection were eliminated. After the cement spacer was removed, the definitive reconstruction was completed with exchange to a cylindrical titanium mesh cage filled with cancellous autograft within the induced membrane. The bone defect with cage was stabilized with a distal femoral Less Invasive Stabilization System (LISS). The radiological and clinical records of the enrolled patients were retrospectively analyzed. ResultsThe mean follow-up was 38.6 months. The average number of operations before the second stage was 1.3. The mean interval between the two stages was 12.7 weeks. The average length of the defect measured 8.3 cm (ranging from 6.1 to 12.4 cm). All the defects filled with autograft within the cage achieved bony union, with a mean healing time of 8.4 months. At the latest follow-up, the mean knee extension measured 6.2° (ranging from 0° to 20°), and the mean flexion measured 101.8° (ranging from 60° to 120°). Complications included two instances of superficial stitch abscess, which eventually healed. ConclusionsThe use of a titanium cage implanted into an induced membrane in a 2-staged Masquelet protocol could achieve satisfactory clinical outcomes in cases of segmental defects following open distal femur fractures.

SAT248 A Case Report Of Hypercalcemia Secondary To Calcium Sulfate Antibiotic Beads

Abstract Disclosure: R. Habibi: None. G. Vahdani: None. N. Ebrahimi: None. Introduction: Periprosthetic joint infections are a rare and uncommon complication in arthroplasties of the hip or knee, happening in ∼0.7% of these procedures. Placement of antibiotic eluting beads, sometimes referred to as calcium sulfate beads (CSB), which are bio-compatible hydrophilic crystals used to deliver antibiotics locally, are one solution to prevent such complications. Hypercalcemia post-CSB placement is a very uncommon, rare and unusual complication that has only been presented in the literature a handful of times. Below, we report on a such a patient, illustrating the importance of surgical history in investigating the cause of hypercalcemia. Presentation: 63yo F with PMH of HTN, HLD, Crohn’s, T2DM, CKD3 who had a recent hospital admission 2 weeks prior for new arthritis secondary to pseudogout crystals, s/p bilateral synovectomy and CSB placement by orthopedics. She was subsequently discharged to nursing facility and re-presented to hospital for increasing AMS and worsening knee pain. Labs showed evidence of AKI with creatinine 1.9, severe hypercalcemia at 17.5 mg/dl with concomitant hypophosphatemia at 1.1 mg/dl. PTHrP WNL &amp; PTH low at 7pg/ml and histo antigen neg, suggesting this was not related to PTH. Malignancy ruled out based on past imaging that was done in 2 months prior. MM ruled out since normal SPEP, UPEP, and kappa:lambda. Unlikely that this was milk alkali as patient did not have alkalosis. Vitamin 1,25 low at 10pg/ml ruling out sarcoidosis. Vitamin 25 WNL. Urine Ca 24hr WNL suggesting no FHH. Ca levels returned to normal after pamidronate, IV fluids and calcitonin. Chart review suggested that CSB implanted in her knees as the likely cause of her hypercalcemia. Discussion: It is important to bring awareness that one of the causes of severe hypercalcemia is post CSB placement. Vigilant monitoring of calcium levels pre and post operation after CSB placement is indicated, particularly in patients with a previous history of CKD. It has been hypothesized that there is a dose-dependent relationship between CSB volume and hypercalcemia, with suggestions that limiting CSB to less than 40ml per operation may be beneficial. A 10ml pack of CSB contains 5.73 grams of elemental calcium which is subsequently released over a 30-60-day interval. There is limited information on the mechanism of hypercalcemia secondary to CSB use, so further studies need to be implemented. Ultimately, it is crucial for physicians to have a high suspicion for CSB induced hypercalcemia post-arthroplasty as CSB use expands. Presentation: Saturday, June 17, 2023

Rare Bipolaris Species Fungal Periprosthetic Hip Infection in an Immunocompetent Host: A Case Report.

We present a case report of a 64-year-old man who developed a rare Bipolaris species fungal periprosthetic joint infection (PJI) after revision arthroplasty for complications associated with a metal-on-metal total hip arthroplasty. The patient underwent a 2-stage debridement with antibiotic bead placement and implant retention, along with chronic antifungal suppression. At the 2-year follow-up, the patient remained asymptomatic. Fungal PJI with filamentous fungi such as Bipolaris species is a rare clinical entity. This case report highlights the clinical presentation and management of this rare condition.

Prophylactic Absorbable Antibiotic Beads for High-risk, Implant-based Prepectoral Reconstruction.

Infections are problematic in postmastectomy implant-based reconstruction with infection rates as high as 30%. Strategies to reduce the risk of infection have demonstrated various efficacies. A prolonged course of systemic, oral antibiotics has not shown evidence-based benefit. Although absorbable antibiotic beads have been described for orthopedic procedures and pressure wounds, their use has not been well studied during breast reconstruction, particularly for prepectoral implant placement. The purpose of this study was to evaluate the selective use of prophylactic absorbable calcium sulfate antibiotic beads during high-risk implant-based, prepectoral breast reconstruction after mastectomy. Patients who underwent implant-based, prepectoral breast reconstruction between 2019 and 2022 were reviewed. Groups were divided into those who received antibiotic beads and those who did not. Outcome variables included postoperative infection at 90 days. A total of 148 patients (256 implants) were included: 15 patients (31 implants) who received biodegradable antibiotic beads and 133 patients (225 implants) in the control group. Patients who received antibiotic beads were more likely to have a history of infection (66.7%) compared with the control group (0%) (P < 0.01). Surgical site infection occurred in 3.2% of implants in the antibiotic bead group compared with 7.6%, but this did not reach statistical significance. The incidence of infection in high-risk patients who have absorbable antibiotic beads placed during the time of reconstruction seems to be normalized to the control group in this pilot study. We present a novel use of prophylactic absorbable antibiotic beads in prepectoral breast implant reconstruction.