Positive Cultures Can Be Safely Ignored in Revision Arthroplasty Patients That Do Not Meet the 2018 International Consensus Meeting Criteria

BackgroundDuring aseptic revision total joint arthroplasty (TJA), one or more cultures may occasionally isolate an organism. The hypothesis of this study was that in a portion of patients undergoing revision arthroplasty for aseptic failure, culture may isolate an organism(s) that can be left untreated.MethodsAll patients undergoing revision TJA from 2000 to 2017 at two institutions were retrospectively reviewed. Patients were categorized as aseptic if they were appropriately investigated preoperatively and did not meet the 2018 International Consensus Meeting criteria. In the aseptic revision cohort, patients with a single positive culture or multiple cultures positive for different organisms (“organism-positive”) and patients who had negative intraoperative cultures (“organism-negative”) were compared based on demographics, comorbidities, operative details, subsequent reoperations, and periprosthetic joint infection (PJI).ResultsIn total, 3,234 International Consensus Meeting–negative aseptic revision TJAs were included, of which 215 patients (6.6%) were organism-positive, 196 (91.2%) had a single positive culture, and 19 (8.8%) were positive for 2 or more distinct organisms (ie, polymicrobial). The most prevalent organisms were coagulase-negative Staphylococci (37.5%), Staphylococcus epidermidis (9.6%), and Cutibacterium acnes (8.0%). Demographics and operative details were comparable between the groups. Using multiple regressions there was no association between culture positivity and the rate of reoperation or PJI.ConclusionIsolation of organisms by culture in patients undergoing revision for aseptic failure was not uncommon. As long as these patients were appropriately investigated preoperatively and PJI was excluded, these findings suggest that culture results may be ignored without subjecting patients to additional antimicrobial treatment.     

Antibiotic prophylaxis in orthognathic surgery: an overview of systematic reviews

The purpose of this overview was to assess different antibiotic regimens used in orthognathic surgery and to establish an evidence-based protocol so that beneficial and adverse effects can be determined. A comprehensive literature search for systematic reviews and/or meta-analyses was conducted in MEDLINE (PubMed), EMBASE, and the Cochrane Library until March 2020. Grey literature was investigated in Google Scholar, and a manual search was done of references lists. Two meta-analyses and four systematic reviews met the inclusion criteria. The AMSTAR-2-tool was used to ascertain the potential risk of bias in the included studies, which presented moderate to high methodological quality. Lower infection rates were associated with long-term therapies of penicillin, cefazolin-cephalexin, and amoxicillin-clavulanic-acid, with rates varying from 0% - 3.13%. Higher rates were reported in placebo groups (52.6%) and short-term penicillin therapy (60%). Side effects were reported with cefazolin, clindamycin, and penicillin therapies, including nausea, pain, swelling, headache, vomiting, and skin rash. Evidence suggests that long-term antibiotics can reduce the risk of a surgical site infection (SSI) in orthognathic surgery, but there is uncertainty regarding the effects of one dose of antibiotics preoperatively versus short-term antibiotics. In the same way, intravenous penicillin, cefazolin, clindamycin, and amoxicillin-clavulanic acid kept the infection rates associated with bimaxillary procedures under 3.5%.     

Therapeutics and delivery vehicles for local treatment of osteomyelitis

Osteomyelitis, or the infection of the bone, presents a major complication in orthopedics and may lead to prolonged hospital visits, implant failure, and in more extreme cases, amputation of affected limbs. Typical treatment for this disease involves surgical debridement followed by long-term, systemic antibiotic administration, which contributes to the development of antibiotic-resistant bacteria and has limited ability to eradicate challenging biofilm-forming pathogens including Staphylococcus aureus—the most common cause of osteomyelitis. Local delivery of high doses of antibiotics via traditional bone cement can reduce systemic side effects of an antibiotic. Nonetheless, growing concerns over burst release (then subtherapeutic dose) of antibiotics, along with microbial colonization of the nondegradable cement biomaterial, further exacerbate antibiotic resistance and highlight the need to engineer alternative antimicrobial therapeutics and local delivery vehicles with increased efficacy against, in particular, biofilm-forming, antibiotic-resistant bacteria. Furthermore, limited guidance exists regarding both standardized formulation protocols and validated assays to predict efficacy of a therapeutic against multiple strains of bacteria. Ideally, antimicrobial strategies would be highly specific while exhibiting a broad spectrum of bactericidal activity. With a focus on S. aureus infection, this review addresses the efficacy of novel therapeutics and local delivery vehicles, as alternatives to the traditional antibiotic regimens. The aim of this review is to discuss these components with regards to long bone osteomyelitis and to encourage positive directions for future research efforts.     

1040例在院病人抗生素一日使用调查报告

目的了解住院病人抗生素使用情况。方法采用横断面调查的方法时我院2005年7月27日所有住院病人抗生素使用情况进行调查。结果抗生素日使用率为34．81％（304／1040），治疗用抗生素占39．67％（144／363），预防用占16．25％（59／363），治疗＋预防占44．08％（160／363），抗生素单用和二联占95．04％（344／363），三联及以上者4．96％（18／363），抗生素日使用种类47种，病原体送检率7．57％（23／304）。结论我院抗生素日使用率不高，抗生素联合使用总体较好，但仍有病原送检率低、抗生素使用品种多、起点高、部分囤术期抗生素预防用药的时机不合理等现象，建议加强宣传教育力度，提高监测速度和指导医师合理用药。     

一种识别蛋白质的保守氨基酸残基的新方法

保守氨基酸残基在生物进化过程中具有较强的稳定性,一般不会发生太大的变化;生物信息学认为：氨基酸序列决定蛋白质结构,蛋白质结构决定蛋白质功能。因此,作者基于氨基酸的生化特性、几何特性和动态特性描述了一个新颖的算法去发现蛋白酶家族中的保守氨基酸残基,而保守氨基酸残基将对蛋白质的结构和功能的研究具有重要的意义。     

The in vitro elution characteristics of vancomycin and tobramycin from calcium sulfate beads

The purpose of this study was to determine the elution characteristics of vancomycin and tobramycin when mixed with calcium sulfate to form antibiotic beads. Calcium sulfate was combined with vancomycin and tobramycin separately to form 2 types of antibiotic beads, which were packaged and labeled separately. The packaged calcium sulfate beads with vancomycin and tobramycin were then gas sterilized. The beads were placed in phosphate-buffered saline and kept at 36 degrees C for 6 weeks. Two separate series of assays were run simultaneously for both types of beads. In one assay, a bead containing vancomycin was placed in a fresh vial of phosphate buffered saline after each assay. The same was done with beads containing tobramycin. In the second series of assays, 9 vials of phosphate buffered saline each containing 1 vancomycin bead and 9 vials of phosphate buffered saline each containing 1 tobramycin bead was arranged. The phosphate-buffered saline was then assayed at predetermined times for both the vancomycin bead series and the tobramycin bead series. The amount of vancomycin and tobramycin assayed nearly equaled the calculated amount of antibiotic per bead measured before bead construction. Also, the elution of antibiotic from the calcium sulfate was complete within 72 hours. In conclusion, the construction and gas sterilization of calcium sulfate beads containing vancomycin and tobramycin does not destroy vancomycin and tobramycin. Also, the complete elution of available vancomycin and tobramycin in calcium sulfate beads occurs within 72 hours.     

马杜霉素渣抗球虫的效果

测定了马杜霉素渣中铅、砷、镉、铬的含量及对小白鼠的毒性和对鸡的抗球虫性能。试验结果：马杜霉素渣中铅含量１．０５ｍｇ／ｋｇ，砷含量小于１．０ｍｇ／ｋｇ，镉含量１．２ｍｇ／ｋｇ，铬含量２６ｍｇ／ｋｇ；马杜霉素渣对小白鼠的ＬＤ５０为３５４．６５ｍｇ／ｋｇ，比马杜霉素毒性大。马杜霉素渣的抗球虫指数为１７３～１７５．１，属中等强度抗球虫药。以上结果表明，马杜霉素渣可以作为抗球虫药应用，但应用时要防止中毒的发生。     

敌枯双慢性毒性实验的病理形态学研究——实验大鼠脏器组织病理变化

将150只SD大鼠随机地分成Ⅰ,Ⅱ,Ⅲ,Ⅳ四个实验组和一个对照组(Ⅴ)。实验组敌枯双剂量分别为1.0,0.2,0.05及0.01mg/kg,均用去离子水配成相应浓度的染毒水,由动物自由摄取,对照组摄入去离子水。于实验第29.5,55周分两批处死。经组织病理学检查,结果发现:敌枯双可引起甲状腺滤泡上皮细胞萎缩甚至脱屑,其发生率(Ⅲ组为63.64%)与对照组(0%)比较差异有高度显著性(P<0.01);睾丸曲细精管各级生精细胞减少、萎缩甚至完全消失,其发生率(Ⅳ组为58.33%)与对照组(8.33%)比较差异有显著性(P<0.01);对心肌、肝组织也有不同程度的损伤.