Shing Samuel R, Hoyt Aaron K, Levack Ashley E
Loyola University Chicago Stritch School of Medicine, 2160 S 1st Ave, Maywood, IL, 60130, USA.
Department of Orthopaedic Surgery and Rehabilitation, Loyola University Medical Center, 2160 S 1st Ave, Maywood, IL, 60153, USA.
J Orthop. 2024 Feb 10;52:74-77. doi: 10.1016/j.jor.2024.02.008. eCollection 2024 Jun.
Antibiotic-laden calcium sulfate beads are gaining popularity in the treatment of orthopaedic infections such as fracture-related infection and osteomyelitis. Calcium sulfate beads have several advantages over polymethylmethacrylate (PMMA) beads as they are bioabsorbable, have demonstrated improved elution characteristics, and have lower peak polymerization temperatures than seen in PMMA. The ability to make and store antibiotic beads for later use has the potential to standardize dosing and decrease operating room times and healthcare costs. This study aims to determine the antibiotic efficacy of premade, antibiotic-laden calcium sulfate beads.
Calcium sulfate beads containing vancomycin or tobramycin were molded to 4.8 mm in diameter and stored for shelf-life durations of three and six months at 20 °C. A subset of beads was tested immediately after creation. At the designated time points, beads were placed into a buffer solution and incubated at 37 °C with agitation. Antibiotic eluent was collected at 1-hour, 4-hour, 24-hour, and 48-hour timepoints. Eluent concentrations were inferred from a prior study implementing the same calcium sulfate bead model. Eluent was used in microbroth dilution assays to determine its minimum inhibitory concentration (MIC) against methicillin-sensitive .
MIC assays for tobramycin and vancomycin against yielded concentrations consistent with previously reported ranges. MIC results across different bead shelf lives also remained consistent without an increase in MIC with increasing shelf life for either antibiotic.
Shelf life up to six months does not impact the efficacy of tobramycin or vancomycin eluent from calcium sulfate beads compared to beads made and tested immediately. These results provide preliminary evidence that tobramycin and vancomycin retain their antimicrobial activity in calcium sulfate beads for at least six months stored at room temperature. Additional studies on sterilization techniques are necessary prior to considering use of prefabricated antibiotic-loaded calcium sulfate beads in clinical practice.
载有抗生素的硫酸钙珠在治疗骨科感染（如骨折相关感染和骨髓炎）方面越来越受欢迎。硫酸钙珠比聚甲基丙烯酸甲酯（PMMA）珠具有几个优点，因为它们是可生物吸收的，具有更好的洗脱特性，并且聚合温度峰值比PMMA低。制备和储存抗生素珠以供日后使用的能力有可能使给药标准化，并减少手术室时间和医疗成本。本研究旨在确定预制的、载有抗生素的硫酸钙珠的抗生素疗效。
将含有万古霉素或妥布霉素的硫酸钙珠模制成直径4.8毫米，并在20°C下储存3个月和6个月的保质期。一部分珠子在制成后立即进行测试。在指定的时间点，将珠子放入缓冲溶液中，并在37°C下搅拌孵育。在1小时、4小时、24小时和48小时时间点收集抗生素洗脱液。洗脱液浓度是根据先前实施相同硫酸钙珠模型的研究推断得出的。洗脱液用于微量肉汤稀释试验，以确定其对甲氧西林敏感菌的最低抑菌浓度（MIC）。
针对甲氧西林敏感菌的妥布霉素和万古霉素的MIC测定产生的浓度与先前报道的范围一致。不同珠保质期的MIC结果也保持一致，两种抗生素的MIC均未随保质期延长而增加。
与立即制成并测试的珠子相比，长达6个月的保质期不会影响硫酸钙珠中妥布霉素或万古霉素洗脱液的疗效。这些结果提供了初步证据，表明妥布霉素和万古霉素在硫酸钙珠中在室温下储存至少6个月仍保留其抗菌活性。在考虑在临床实践中使用预制的载抗生素硫酸钙珠之前，有必要对灭菌技术进行进一步研究。
