Antibiotic related acute kidney injury in patients treated for open fractures

ObjectiveAntibiotic administration during the treatment of open fractures has been shown to reduce infection rates and is considered a critical step in the management of these injuries. The purpose of this study was to determine if aminoglycoside administration during the treatment of open fractures leads to acute kidney injury.MethodsPatient records at a level I trauma centre were reviewed for adult patients who presented in 2014 with open fractures were screened for inclusion. Patients were excluded with fractures of the phalanges, metatarsals, and metacarpals, with isolated traumatic arthrotomies, or pre-existing renal dysfunction. Charts were reviewed for patient age, gender, race, past medical history, medication history, injury severity score, intravenous dye studies and fracture type. Patients were divided into those given cefazolin (Group A) and cefazolin with gentamicin (Group B). Laboratory values were used to determine which patients developed kidney dysfunction as measured using the RIFLE criteria. Wilcoxon–Mann–Whitney test and Chi-square were used to compare interval and categorical variables, respectively. Significance was set at P < 0.05.ResultsOne-hundred and fifty-nine patients met inclusion criteria. Forty-one (25%) patients were given cefazolin alone and 113 (68%) patients were given cefazolin with gentamicin. Ten (18%) patients with Gustilo-Anderson type III fractures were given cefazolin alone and 67 (67%) patients with types I or II fractures were given a cefazolin with gentamicin. Baseline characteristics and risk factors for renal dysfunction did not vary between groups. Two (4.8%) patients in Group A and 5 (4%) patients in Group B developed acute kidney injury (P = 0.599).ConclusionsGentamicin use during the treatment of open fractures does not lead to increased rates of renal dysfunction when used in patients with normal baseline renal function.     

Polymorphic karyotypes in related Acremonium strains

Summary A restriction fragment length polymorphism (RFLP) analysis was performed on six related Acremonium strains. With respect to the restriction fragment pattern, all strains of A. chrysogenum were indistinguishable from each other but showed distinctive differences from those of A. strictum, A. flavum and Cephalosporium polyvaleurum. Using pulsed-field gel electrophoresis, we obtained different chromosome patterns from most of the Acremonium strains. Remarkably, the pattern varies in three related A. chrysogenum strains which also differ in their rate of cephalosporin C biosynthesis. The electrophoretic karyotyping was confirmed by the location of rDNA genes on separate chromosomes. Our data indicate that chromosome translocations in industrial strains may be responsible for increased -lactam synthesis.     

紫外线与亚硝酸复合诱变在顶头孢霉菌选育中的应用

为了提高头孢菌素C的产量,通过对头孢菌素C产生菌顶头孢霉菌B42-V2进行紫外线和亚硝酸的复合诱变处理,得到变株B42-V2N,单位提高10．04％,且遗传性状非常稳定。实验表明：紫外线和亚硝酸复合诱变,操作简便、安全高效,所选育菌种遗传性状稳定。     

Salmonella meningitis: clinical experience of third-generation cephalosporins

Fifteen paediatric patients with Salmonella meningitis were retrospectively reviewed. Presenting symptoms and signs included fever, vomiting, seizures, poor activity, diarrhoea and bulging anterior fontanelle in most patients. Seven out of eight patients with prolonged fever for > 10 days had neurologic sequelae; therefore, prolonged fever is a significant prognostic factor of a poor outcome ( p < 0. 005). All 15 patients had a brain ultrasound or computed tomography in the acute stage and 11 patients had abnormal findings. The 14 surviving patients were treated with a third-generation cephalosporin for at least 3 weeks. Seven patients (47%) made complete recoveries; two of them were treated solely with a third-generation cephalosporin. Only one mortality (6%) occurred and there were no relapses. In conclusion, high frequencies of prolonged fever, neuroimaging abnormalities and neurologic sequelae were seen in patients with Salmonella meningitis treated with third-generation cephalosporins.     

New concepts in the field of cephalosporins: C-3'quaternary ammonium cephems (Group IV)

The C-3' quaternary ammonium cephems belong to group IV of the microbiological classification of cephalosporins. This group is divided into two subgroups according to the position of the quaternary ammonium moiety (C-3 or C-7). These compounds are structurally related to the third-generation cephalosporins (or group III of the microbiological classification), but in addition are featured with two or more of the following properties: broad-spectrum activity including Pseudomonas aeruginosa; activity against Enterobacteriaceae producing type 1 β-lactamase; the presence of a quaternary moiety. The zwitterionic properties of the C-3' quaternary cephalosporins allow rapid penetration through the outer membrane of Gram-negative bacteria, stability to and low affinity for type 1 β-lactamases in the periplasmic space and high affinity for the penicillin binding proteins (PBPs). Among the currently available analogues cefpirome and cefozopran exhibit a well-balanced antibacterial spectrum against Gram-negative bacilli and Gram-positive cocci. Cefepime is less active against Staphylococcus aureus.     

Extended-spectrum cephalosporins and the inoculum effect in tests with CTX-M-type extended-spectrum β-lactamase-producing Escherichia coli: Potential clinical implications of the revised CLSI interpretive criteria

Based on the new recommendations of the Clinical and Laboratory Standards Institute (CLSI), the revised cephalosporin breakpoints may result in many CTX-M-producing Escherichia coli being reported as susceptible to ceftazidime. We determined the activity of ceftazidime and other parenteral β-lactam agents in standard- and high-inoculum minimum inhibitory concentration (MIC) tests against CTX-M-producing E. coli isolates. Antimicrobial susceptibility was determined using a broth microdilution MIC method with inocula that differed 100-fold in density. An inoculum effect was defined as an eight-fold or greater increase in MIC on testing with the higher inoculum. When the revised CLSI ceftazidime breakpoint of 4 μg/mL was applied, 34 (34.3%) of the 99 CTX-M-producers tested were susceptible. More specifically, for 42 CTX-M-14-producing E. coli isolates, 32 (76.2%) were susceptible at 4 μg/mL. Cefotaxime, ceftazidime, cefepime and piperacillin/tazobactam were found to be associated with inoculum effects in 100% of the evaluable tests for extended-spectrum β-lactamase-producing E. coli isolates. The MIC₅₀ (MIC required to inhibit 50% of isolates) of ceftazidime was 16 μg/mL in the standard-inoculum tests and >512 μg/mL in the high-inoculum tests. In the high-inoculum tests including isolates encoding CTX-M-14, ceftazidime was dramatically affected, with susceptibility decreasing from 82.1% of isolates inhibited at 4 μg/mL in the standard-inoculum tests to 0% at high inoculum. Although further studies may demonstrate that ceftazidime has a role in the treatment of infections caused by these organisms, we suggest that until more data become available, clinicians should be cautious about treating serious CTX-M-producing E. coli infections with ceftazidime or cefepime.     

头孢菌素类药物严重不良反应回顾性分析

目的对头孢菌素类药物严重不良反应进行回顾性分析以减少严重不良反应的发生。方法选取因头孢菌素类药物产生严重不良反应的68例,对其发生的情况及临床特点进行回顾性分析。结果15个品种的头孢菌素类药物发生频率最高,其中不良反应发生率最高的是注射用头孢替唑钠,发生率为9．1％;其次为头孢哌酮／舒巴坦纳。发生率为2．5％,对患者产生严重不良反应,引起近10个系统发生不良反应。其中较常见的不良反应为变态反应、过敏性休克、双硫仑样反应,发生率为55．00％;其次为呼吸困难,发生率为14．16％。结论头孢菌素类药物使用时,应详细地了解该药物引起不良反应的临床特点,以避免严重不良反应的发生。     

农杆菌转化法高效构建顶头孢霉sorA和sorB双缺失菌株提高头孢菌素C产量

目的 获得顶头孢霉sorA和sorB双缺失菌株，以阻断sorbicillinoids的合成，并研究其与头孢菌素C(CPC)产量的关系。方法 通过根癌农杆菌转化法，依据同源双交换的原理，同时敲除合成sorbicillinoids骨架结构的两个聚酮合酶基因sorA和sorB，并通过摇瓶发酵实验检测缺失菌和野生菌的产量。结果 筛选并验证了6株A. chrysogenum-?pks菌株，遗传稳定，转化效率约为20%。通过发酵实验测定发现，缺失菌株产CPC能力比野生菌提高了70%。结论 农杆菌转化法是一个高效的顶头孢霉遗传操作系统，并且顶头孢霉中sorbicillinoids的缺失可以提高CPC产量。     

三角酵母D-氨基酸氧化酶的固定化研究

通过共价结合的方法把三角酵母D—氨基酸氧化酶(DAO)分别固定在三种大孔高聚物和二种多糖的载体上，结果表明多糖类载体壳聚糖和Sepharose 4B比高聚物更能有效地固定化DA0。经过固定化后，壳聚糖和环氧载体Epecust固定化酶对温度和pH的稳定性提高，表现米氏常数增大。在分批式头孢菌素C氧化脱氨的反应中，固定化酶表现出良好的操作稳定性，戊二酸单酰基—7—氨基头孢霉烷酸的得率为93％。     

某院头孢菌素类药的利用及皮肤试敏情况分析

目的：调查分析某院2009年1～6月注射用头孢菌素类药的利用及皮肤试敏（简称皮试）情况.方法：运用药物利用研究的方法,分析头孢菌素类药的使用情况;统计选择应用头孢菌素类药原液进行皮试的出院病例（975例）,分析皮试阳性率与用药频度（DDDs）之间的相关性.结果：金额排序/DDDs排序的排序比≥1的药物占77.8%;头孢菌素类药原液皮试阳性率为18.8%,与DDDs之间没有相关性（P＞0.05）.结论：该院注射用头孢菌素类药的使用基本合理;头孢菌素类药原液皮试阳性率相对较高,与DDDs之间没有相关性.