Therapeutic utility of antibacterial peptides in wound healing

Cationic antimicrobial peptides were first thought to fight infection in animal models by disintegrating bacterial peptides and later by inhibiting bacteria-specific intracellular processes. However, ever increasing evidences indicate that cationic peptides accumulate around and modulate the immune system both systemically and in cutaneous and mucosal surfaces where injuries and infections occur. Native and designer antibacterial peptides as well as cationic peptides, never considered as antibiotics, promote wound healing at every step of cutaneous tissue regeneration. This article provides an introductory list of examples of how cationic peptides are involved in immunostimulation and epithelial tissue repair, eliminating wound infections and promoting wound healing in potential therapeutic utility in sight. Although a few antimicrobial peptides reached the Phase II clinical trial stage, toxicity concerns limit the potential administration routes. Resistance induction to both microbiology actions and the integrity of the innate immune system has to be carefully monitored.     

PCR for detection of respiratory viruses: seasonal variations of virus infections

Real-time PCR and related methods have revolutionized the laboratory diagnosis of viral respiratory infections because of their high detection sensitivity, rapidness and potential for simultaneous detection of 15 or more respiratory agents. Results from studies with this diagnostic modality have significantly expanded our knowledge about the seasonality of viral respiratory diseases, pinpointed the difficulties to make a reliable etiologic diagnosis without the aid of an unbiased multiplex molecular assay for respiratory viruses, and revealed previously unknown details as to possible infections with multiple agents as aggravating factors. The scope of this article is to review and discuss this new knowledge and its implications for diagnostic strategies and other measures essential for the clinical management of respiratory viral infections and for epidemiological surveillance of seasonal respiratory infections.     

What is next in sepsis: current trials in sepsis

17th International Symposium on Infections in the Critically Ill Patient

Barcelona, Spain, 3–4 February 2012

International experts reviewed and updated the most recent and relevant scientific advances on severe sepsis during the 17th International Symposium on Infections in the Critically Ill Patients in Barcelona (Spain) in February 2012. All new pharmacological therapeutic strategies have failed to demonstrate a survival benefit. Despite the large variability among countries and hospitals, the improvement of standard care according to the Surviving Sepsis campaign recommendations reduced the 28-day mortality to 24%. These results may have implications for future clinical trials in which much larger samples sizes of patients at high risk of death will be necessary. The identification of novel proinflammatory endogeneous signals and pathways may lead to the discovery of new drugs to reduce inflammatory reactions and end-organ dysfunction in critically ill patients with sepsis. Extracorporeal blood purification stem or progenitor cells have received increasing interest for the treatment of inflammation and organ injury. A better understanding of how these therapies work is essential and its benefit should be confirmed in future prospective randomized studies.     

呼吸内科不同区域下呼吸道感染耐药菌分布及耐药特征比较分析

目的：探索昆明医科大学第一附属医院呼吸内科不同区域[门诊、病房,呼吸重症监护病房（RIC U ）]下呼吸道感染耐药菌株的分布构成及耐药特征,为临床抗菌药物的合理应用提供依据。方法采用K‐B纸片扩散法和仪器法（VITEK‐TWO）,按照美国临床与实验室标准化研究所（CLSI）2010年版标准判读结果,对昆明医科大学第一附属医院呼吸科门诊、病房、RICU患者送检的痰液、肺泡灌洗液标本通过细菌培养鉴定及药敏试验分离出的480株耐药菌株,用WHONET5．6软件对检测数据进行分析。结果该医院呼吸门诊、病房、RICU下呼吸道感染耐药菌分布构成前4位均以革兰阴性菌为主。肺炎克雷伯菌对多数抗菌药物的耐药率大于30％,对庆大霉素、左氧氟沙星、氨苄青霉素的耐药率大于50％,RIC U与呼吸科门诊和病房相比差异有统计学意义（ P＜0．05）。亚胺培南、哌拉西林／他唑巴坦、头孢哌酮／舒巴坦、阿米卡星抗菌活性较强,其耐药率小于20％。大肠埃希菌对11种常用抗菌药物在呼吸科门诊、病房与RICU的耐药率相似。产超广谱β‐内酰胺酶（ESBLs）菌株的多重耐药率明显高于非产ESBLs菌株（P＜0．05）,产ESBLs菌株对亚胺培南耐药率小于10％。铜绿假单胞菌对头孢哌酮／舒巴坦、哌拉西林／他唑巴坦、头孢吡肟、喹诺酮类、氨基糖甙类在呼吸科门诊和病房仍保持较高的抗菌活性,但RIIU的耐药率大于54％（ P＜0．05）。鲍曼不动杆菌对亚胺培南的耐药率在RIC U和病房明显高于呼吸科门诊,分别为70．4％、64．6％和46．2％。RIC U检出的耐甲氧西林金黄色葡萄球菌（MRSA）对利福平耐药率明显高于呼吸科门诊和病房（P＜0．05）。结论呼吸科门诊、病房和RICU的耐药菌分布构成及耐药率均有明显差异,临床医师除了熟悉本地区耐药菌分布及耐药率监测情况外,还应掌握本单位各科室不同区域耐药菌的耐药率情况,才能正确有效合理应用抗菌药物。     

碳青霉烯类耐药肺炎克雷伯菌感染死亡风险预测模型的建立及其对患者预后的预测价值研究

背景　肺炎克雷伯菌是院内感染常见致病菌，碳青霉烯类抗生素是治疗其感染的“最后一道防线”。近年来由于抗生素尤其是耐碳青霉烯类的过量暴露，碳青霉烯类耐药肺炎克雷伯菌（CRKP）引起的院内感染增加，其检出率亦随医疗技术的进步而逐年增加。CRKP感染后，临床可供选择的敏感抗生素屈指可数，且抗感染治疗效果不佳，死亡率也随之上升。目的　探究CRKP感染患者发生死亡的危险因素，建立CRKP感染死亡风险预测模型，并评估该模型对患者预后的预测价值。方法　收集2017年1月-2019年4月西安交通大学第二附属医院收治的199例CRKP感染患者的临床资料。将2017年1月-2018年12月收治的患者作为建模组（n=138），2019年1-4月收治的患者作为验证组（n=61）。将建模组的患者依据离院时状态分为存活亚组、死亡亚组，分别为104例和34例。比较存活亚组和死亡亚组患者一般资料、基础疾病、入院前治疗情况、住院期间并发症、有创治疗情况、初始治疗（3 d）后血生化指标及体温、入院后治疗情况等。采用多因素Logistic回归分析探究CRKP感染患者发生死亡的影响因素，并依据多因素Logistic回归分析结果的相关系数建立CRKP感染死亡风险预测模型，分别绘制CRKP感染死亡风险预测模型预测建模组及验证组患者发生死亡的受试者工作特征（ROC）曲线。结果　建模组患者死亡率为24.6%（34/138），验证组患者死亡率为24.6%（15/61）。多因素Logistic回归分析结果显示，住院期间并发多器官功能障碍综合征（MODS）、初始治疗后急性生理学与慢性健康状况评分系统Ⅱ（APACHEⅡ）评分≥14分、使用血管活性药物是CRKP感染患者发生死亡的影响因素（P<0.05）。CRKP感染死亡风险预测模型回归方程=住院期间并发MODS×2.4+（初始治疗后APACHⅡ评分≥14分）×1.5+使用血管活性药物×2.0。将CRKP感染死亡风险预测模型应用于建模组患者，H-L检验P值为0.866；应用于验证组患者，H-L检验P值为0.807。CRKP感染死亡风险预测模型预测建模组患者发生死亡的ROC曲线下面积（AUC）为0.851〔95%CI（0.774，0.928）〕，最佳截断值为2.75，灵敏度为84.4%，特异度为76.0%，约登指数为0.584。CRKP感染死亡风险预测模型预测验证组患者发生死亡的AUC为0.966〔95%CI（0.894，1.000）〕，最佳截断值为2.95，灵敏度为100%，特异度为87.0%，约登指数为0.870。结论　住院期间并发MODS、初始治疗后APACHEⅡ评分≥14分、使用血管活性药物是CRKP感染患者发生死亡的独立危险因素，依据上述指标拟合出的CRKP感染死亡风险预测模型对CRKP感染患者预后具有较好的预测价值。     

儿童反复上呼吸道感染补充维生素D后LL-37水平的变化研究

背景　流行病学调查显示全球大约有10亿人存在维生素D缺乏或不足,我国维生素D缺乏尤为严重。反复上呼吸道感染作为小儿常见病及多发病,严重影响小儿身心健康,维生素D缺乏是导致抗菌肽LL-37下调的主要原因,因此维生素D缺乏越来越引起人们的重视。目的　探讨反复上呼吸道感染患儿补充维生素D后LL-37水平变化。方法　选取2017年5-11月河北大学附属医院门诊就诊的反复上呼吸道感染并存在维生素D不足或缺乏的患儿54例,采用随机数字表法分为试验组及对照组,每组各27例。试验组给予常规治疗联合补充维生素D,对照组给予常规治疗联合安慰剂,随访12个月,记录治疗前和治疗后12个月时上呼吸道感染次数,检测血浆25-羟维生素D3及痰上清LL-37的变化。结果　45例患儿完成了随访,试验组23例,对照组22例。治疗前,两组患儿上呼吸道感染次数、血浆25-羟维生素D3及痰上清LL-37水平比较,差异均无统计学意义（P>0.05）;治疗后12个月,试验组患儿上呼吸道感染次数少于对照组,血浆25-羟维生素D3、痰上清LL-37水平高于对照组（P<0.05）。对照组患儿治疗前后上呼吸道感染次数、血浆25-羟维生素D3及痰上清LL-37水平比较,差异均无统计学意义（P>0.05）;试验组患儿治疗后12个月上呼吸道感染次数少于治疗前,血浆25-羟维生素D3、痰上清LL-37水平高于治疗前（P<0.05）。Pearson直线相关分析结果显示,试验组治疗后12个月血浆25-羟维生素D3与痰上清LL-37呈正相关（r=0.505,P<0.05）。结论　补充维生素D有助于减少反复上呼吸道感染患儿上呼吸道感染次数,这种作用可能与LL-37产生增加有关。     

冠状病毒肺炎细胞因子风暴及免疫调控治疗

细胞因子风暴是一种失控的过度免疫应答,是冠状病毒肺炎的重要发病机制。病毒劫持机体的免疫系统,导致免疫调节的负反馈丧失、多种细胞因子异常升高,损害了肺泡弥散功能并造成多器官功能障碍。靶向冠状病毒细胞因子风暴的特异性治疗研究,如粒细胞集落刺激因子、托珠单抗、卡莫他特、血液净化治疗等已取得系列成果,其可能是缓解新型冠状病毒肺炎（COVID-19）疫情的有效手段。但COVID-19具有独特的病理特征,上述治疗的研究成果仍需进一步临床试验来验证。本文就冠状病毒肺炎细胞因子风暴及免疫调控治疗进展进行综述。     

Urinary tract infections: what's new?

PURPOSE: This review provides practicing urologists with important basic information about urinary tract infections (UTIs) that can be applied to everyday clinical problems. MATERIALS AND METHODS: A review is presented of provocative and controversial concepts in the current literature. RESULTS: Bacterial virulence mechanisms are critical for overcoming the normal host defenses. Increasing antimicrobial resistance of uropathogens has led to reconsideration of traditional treatment recommendations in many areas. For effective patient management the first issue is to define complicating urological factors. Managing complicated urinary tract infections, particularly in urology, is determined by clinical experience to define the pertinent anatomy and to determine the optimal interventions. New clinical data are summarized on UTIs in long-term care patients, behavioral risks for UTI in healthy women and anatomical differences associated with an increased risk for UTI. The rationale is presented for UTI prophylaxis using cranberry juice, immunization and bacterial interference. Current treatment trends for UTI include empiric therapy (without urine culture and sensitivity testing), short-course therapy, patient-administered (self-start) therapy and outpatient therapy for uncomplicated pyelonephritis. CONCLUSIONS: Recommendations for treating patients with UTIs have changed based on basic science and clinical experience.     

Direct exchange endoprosthetic reconstruction with tumour prosthesis for periprosthetic knee infection associated with segmental bone defects

Revision knee arthroplasty for infection poses a treatment challenge. The presence of massive osteolysis limits the treatment options in this cohort. Controversy exists in the management of these patients. Direct exchange arthroplasty has provided good results in the presence of infection, but whether this is appropriate in the presence of massive bone defects associated with the infection is undetermined. We present our experience in revision knee arthroplasty for infection associated with massive bone defects. The aim of the study is to present the preliminary results of a direct exchange endoprosthetic reconstruction with tumour prosthesis for periprosthetic infection associated with segmental bone defects. This is a retrospective study of prospectively collected data, involving six patients with periprosthetic infection and massive bone defects treated by direct exchange tumour prostheses between 2003 and 2007 (four distal femoral replacements and two total femoral replacements). The mean age and follow-up were 74.2 (±5.2) years and 32.5 (±8.2) months respectively. Each patient had an infected revised knee arthroplasty at the time of referral to our institution. Staphylococcus aureus was the most common causal organism. The mean duration of antibiotics was 6 weeks intravenous therapy followed by 3.5 months oral. The recurrences of infection, pain or immobility were outcome criteria considered failures. Our success rate was 80%. Salvage of infected revised knee arthroplasty by direct exchange endoprosthetic reconstruction has provided an effective means of pain relief, joint stability and improved mobility in our cohort. It reduces morbidity through earlier mobilisation and avoids a second major operation.