Acinetobacter infection associated with pneumonia in an orangutan

A 23-year old male orangutan (Pongo pygmaeus) had been treated for two years for respiratory disease believed to be tuberculosis. Terminally, the animal developed mucopurulent rhinitis and refused food. Necropsy examination revealed diffuse, severe, bilateral chronic pleuritis, fibrinous bronchopneumonia and air sacculitis. Large numbers of gram-negative bacteria seen in the lung histologically were cultured from both the lung and air sacs and identified asAcinetobacter calcoaceticus varietylwoffi. The resistance of the isolatein vitro to ampicillin may have accounted for the lack of clinical response of the ill orangutan.     

呼吸机相关性肺炎患者病原菌分布及IL 35的炎症控制机制

目的 探讨呼吸机相关性肺炎(VAP)患者病原菌分布及白细胞介素35(IL 35)的炎症控制机制。 方法 回顾性分析2016年12月至2018年12月在我院重症监护病房(ICU)行机械通气的152例患者的临床资料,根据是否发生VAP将其分为VAP组(n=70)和对照组(n=82)。收集VAP患者痰液进行细菌培养及药敏实验,检测并比较两组患者外周血单个核细胞(PBMCs)中CD4+CD25+CD127dim/ 调节性T细胞(Tregs)比例及血清中白细胞介素35(IL 35)、肿瘤坏死因子α(TNF α)、干扰素 γ(IFN γ)水平;同时检测并比较经佛波酯和重组人IL 35刺激后的Tregs细胞培养液上清中IL 35、IFN γ、TNF α水平。 结果 70例VAP患者共检出病原菌128株,其中革兰阴性菌占82.81%,革兰阳性菌占14.84%,真菌占2.34%。鲍曼不动杆菌对头孢西丁的耐药率最高,对头孢哌酮的耐药率最低。铜绿假单胞菌对头孢西丁的耐药率最高,对亚胺培南的耐药率最低。肺炎克雷伯菌对头孢西丁的耐药率最高,对头孢哌酮的耐药率最低。VAP组患者PBMCs中CD4+CD25+CD127dim/ Tregs比例及血清中IL 35、IFN γ、TNF α水平显著高于对照组(t=12.675、36.631、13.464、8.482,均P结论 呼吸机相关性肺炎病原菌以革兰阴性菌为主,呈现多药耐药性,临床应合理使用抗菌药物以防治呼吸机相关性肺炎。IL 35可通过调控Tregs功能降低促炎因子分泌从而在呼吸机相关性肺炎发病过程中发挥抗炎症作用,提示IL 35可能为呼吸机相关性肺炎的治疗提供新的方向。     

Role of T cells in virus control and disease after infection with pneumonia virus of mice

Infection of mice with pneumonia virus of mice (PVM) is used as a natural host experimental model for studying the pathogenesis of infection with the closely related human respiratory syncytial virus. We analyzed the contribution of T cells to virus control and pathology after PVM infection. Control of a sublethal infection with PVM strain 15 in C57BL/6 mice was accompanied by a 100-fold increase in pulmonary cytotoxic T lymphocytes, 20% of which were specific for PVM. T-cell-deficient mice failed to eliminate PVM and became virus carriers in the absence of the clinical or histopathological signs of pneumonia that occurred after infection of control mice. Mice with limited T-cell numbers did not achieve virus control without weight loss, indicating that T-cell-mediated virus control was closely linked to immunopathology. Both CD4 and CD8 T cells independently contributed to virus elimination and disease. Virus control and disease were similar in the absence of perforin, gamma interferon, or tumor necrosis factor alpha. Interestingly, disease and mortality after lethal high-dose PVM infection were independent of T cells. These data illustrate a key role for T cells in control of PVM infection and demonstrate that both T-cell-dependent and -independent pathways contribute to disease in a viral dose-dependent fashion.     

肺炎支原体致病机制及其疫苗的研究进展

肺炎支原体(Mycoplasma pneumoniae,MP)是导致儿童社区获得性肺炎的常见病原体之一.MP感染人体后可造成多个系统的损害.随着耐药现象的出现,重症或难治性肺炎患儿增多,为临床治疗带来了巨大的挑战.疫苗是预防肺炎支原体肺炎(Mycoplasma pneumoniae pneumonia,MPP)最有效的...     

纤支镜导致呼吸机相关肺炎感染暴发的调查研究

目的调查分析疑似纤支镜清洗消毒不规范引起的医院感染暴发事件,为采取针对性控制措施提供依据。方法采用流行病学调查和病例对照研究的方法对医院感染病例进行分析,并提出综合干预措施。结果综合ICU使用呼吸机支持治疗患者,14天内发生的4例呼吸机相关肺炎患者均经纤支镜检查,4例患者痰标本中均培养出铜绿假单胞菌,纤支镜采样细菌培养出铜绿假单胞菌。结论使用不规范清洗消毒的纤支镜进行检查是引起综合ICU住院患者呼吸机相关肺炎感染的主要危险因素。重视医院感染控制,采取有效的消毒隔离措施,严格消毒灭菌技术操作,是预防和控制医院感染爆发的有效措施和途径。     

Uncommon pneumonia associated with acute poststreptococcal glomerulonephritis

184 cases of acute poststreptococcal glomerulonephritis were investigated and six of these were associated with a peculiar, uncommon pneumonia, and another one had a lethal course. The clinicoradiological and especially pathological data summarized in this study attempt to demonstrate the individuality of this type of pneumonia. Pneumonia associated with acute poststreptococcal glomerulonephritis is similar or identical to rheumatic pneumonia. In both entities, pneumonia and pulmonary edema may and do coexist, and the differentiation of pneumonia from congestive heart failure is difficult and often impossible without pathological evidence. The most attractive pathogenic interpretation is the hypothesis of an immune mechanism in the induction of pneumonia. Authors attributed the lung changes, consecutive to a vascular damage, to a hypersensitivity phenomenon, with accumulation of fibrinogen in alveoli where it is converted to fibrin. Then, the hyaline membrane lining the alveoli, an important feature of pneumonia associated with glomerulonephritis is built up. It is, however, plausible that the effect of the immune reaction is associated with those of hydrosaline retention, arterial hypertension and congestive heart failure. Analogous to rheumatic pneumonia, the "peculiar pneumonia" associated with acute poststreptococcal glomerulonephritis should be named nephritic pneumonia.     

Therapeutic use of quercetin in the control of infection and anemia associated with visceral leishmaniasis

Flavonoids are a broad class of plant phenolics that are known to possess a well-established protective effect against membrane lipoperoxidative damages. Oxidative damage of erythrocytes has been implicated in the reduced survival of erythrocytes during leishmanial infection. This study reveals the efficacy of five naturally occurring flavonoids in arresting the development of anemia during the postinfection period. Among the compounds studied, quercetin was most successful in inhibiting the oxidation of proteins and lipids on the red cell membranes of infected animals. Apart from its antianemic property, quercetin also seemed to be highly potent in lowering the parasite load in the spleen. Combination therapy of quercetin with the antileishmanial drug stibanate produced a better decay of .OH in the erythrocytes of the infected animals compared to that induced by quercetin or drug treatment alone. Similar results were obtained in successful prevention of proteolytic degradation resulting in an aversion to early lysis of red cells after simultaneous treatment with quercetin and stibanate. Subsequent studies demonstrated the therapeutic efficacy of the combination treatment in the abatement of both anemia and parasitemia under the diseased condition.     

儿童重症监护病房呼吸机相关性肺炎病原菌分布及耐药性分析

目的探讨儿童重症监护病房(PICU)机械通气患儿呼吸机相关性肺炎(VAP)的病原菌群,并对细菌耐药性进行分析,为抗生素的使用提供依据。方法对2012年6月至2015年5月我院PICU中发生的34例VAP患儿的下呼吸道分泌物细菌培养结果进行回顾性分析。结果共计检出病原菌40株,其中革兰阴性菌34株(85.0%),革兰阳性菌4株(10.0%),真菌2株(5.0%)。前四位致病菌依次为:鲍曼不动杆菌(25.0%)、肺炎克雷伯菌(20.0%)、铜绿假单胞菌(15.0%)、大肠埃希菌(12.5%),均对儿科常用抗生素耐药性严重。鲍曼不动杆菌对头孢哌酮/舒巴坦耐药率较低,肺炎克雷伯菌、大肠埃希菌对亚胺培南、哌拉西林/他唑巴坦的耐药率较低,铜绿假单胞菌则对喹诺酮类耐药率较低。结论应加强机械通气儿童患者呼吸道管理及病原学监测,合理应用抗生素。     

神经外科术后患者呼吸机相关性肺炎危险因素分析

目的 探讨神经外科术后患者呼吸机相关性肺炎(VAP)的病原菌分布、耐药性及其危险因素。 方法 选取我院神经外科ICU于2015年6月至2019年1月期间收治的286例手术后行机械通气患者为研究对象,将出现VAP的患者纳入感染组,将未出现VAP的患者纳入未感染组,对感染组患者进行呼吸道分泌物分离培养鉴定,并进行药敏试验。同时收集所有患者的临床资料,对患者发生VAP的危险因素进行分析。 结果 286例患者中共有117例患者发生VAP,VAP发生率为40.9%。117例VAP患者共培养得到148株病原菌,其中革兰阴性菌共97株,占65.5%,革兰阴性菌中主要为铜绿假单胞菌、鲍曼不动杆菌、肺炎克雷伯菌;革兰阳性菌共44株,占29.7%,其中以金黄色葡萄球菌和表皮葡萄球菌为主;真菌7株,占4.7%。药敏试验提示革兰阴性菌中铜绿假单胞菌对阿米卡星最为敏感,而对左氧氟沙星和美罗培南均具有较高的耐药性;鲍曼不动杆菌主要对头孢哌酮和环丙沙星耐药性较低,对庆大霉素和哌拉西林耐药性高;肺炎克雷伯菌对常见抗菌药物耐药性整体较高,仅对阿米卡星、美罗培南、亚胺培南耐药性较低。革兰阳性菌中均未发现对替考拉宁、万古霉素耐药的菌株,其中金黄色葡萄球菌对大多数抗菌药物的耐药性均超过50%,仅对利福平耐药性低于50%;表皮葡萄球菌对青霉素和亚胺培南具有100%的耐药性,对庆大霉素和环丙沙星具有50%的耐药性,对其他抗菌药物的耐药性均较低。Logistic回归分析显示年龄≥60岁、机械通气时间较长、脱机失败再插管、联合使用抗生素、长时间使用抗生素均为神经外科手术后患者出现VAP的独立危险因素。 结论 神经外科术后机械通气患者VAP的发生率较高,且病原菌的耐药性较高,同时患者发生VAP的危险因素较多,应针对相关危险因素进行有效的干预以减少VAP的发生,提高患者的预后。     

Modulation of respiratory dendritic cells during Klebsiella pneumonia infection

Background

Klebsiella pneumoniae is a leading cause of severe hospital-acquired respiratory tract infections and death but little is known regarding the modulation of respiratory dendritic cell (DC) subsets. Plasmacytoid DC (pDC) are specialized type 1 interferon producing cells and considered to be classical mediators of antiviral immunity.

Method

By using multiparameter flow cytometry analysis we have analysed the modulation of respiratory DC subsets after intratracheal Klebsiella pneumonia infection.

Results

Data indicate that pDCs and MoDC were markedly elevated in the post acute pneumonia phase when compared to mock-infected controls. Analysis of draining mediastinal lymph nodes revealed a rapid increase of activated CD103⁺ DC, CD11b⁺ DC and MoDC within 48 h post infection. Lung pDC identification during bacterial pneumonia was confirmed by extended phenotyping for 120G8, mPDCA-1 and Siglec-H expression and by demonstration of high Interferon-alpha producing capacity after cell sorting. Cytokine expression analysis of ex vivo-sorted respiratory DC subpopulations from infected animals revealed elevated Interferon-alpha in pDC, elevated IFN-gamma, IL-4 and IL-13 in CD103⁺ DC and IL-19 and IL-12p35 in CD11b⁺ DC subsets in comparison to CD11c⁺ MHC-class II^low cells indicating distinct functional roles. Antigen-specific naive CD4⁺ T cell stimulatory capacity of purified respiratory DC subsets was analysed in a model system with purified ovalbumin T cell receptor transgenic naive CD4⁺ responder T cells and respiratory DC subsets, pulsed with ovalbumin and matured with Klebsiella pneumoniae lysate. CD103⁺ DC and CD11b⁺ DC subsets represented the most potent naive CD4⁺ T helper cell activators.

Conclusion

These results provide novel insight into the activation of respiratory DC subsets during Klebsiella pneumonia infection. The detection of increased respiratory pDC numbers in bacterial pneumonia may indicate possible novel pDC functions with respect to lung repair and regeneration.     

血液中肺炎克雷伯菌碳青霉烯类耐药危险因素的调查

目的探讨血液中分离的肺炎克雷伯菌耐碳青霉烯类抗菌药物的危险因素,为临床治疗提供理论依据。方法回顾性收集2009年6月至2012年12月期间血液中分离出肺炎克雷伯菌的住院患者的临床资料,采用病例对照研究,单因素分析和多因素Logistic回归分析血液感染肺炎克雷伯菌耐碳青霉烯类抗菌药物的危险因素。结果泌尿道插管、血型(A型)、使用氨基糖苷类及抗真菌类抗菌药物是血液感染肺炎克雷伯菌耐碳青霉烯类抗菌药物的独立危险因素。结论临床治疗过程中,需要特别注意的环节是:泌尿道插管;氨基糖苷类和抗真菌类抗菌药物的合理使用。     

Lethal pneumonia in guinea pigs associated with a virus

No bacteria were observed in an epizootic of lethal pneumonia in guinea pigs. Necrotic bronchitis and bronchiolitis with basophilic intranuclear inclusion bodies in bronchial epithelial cells were characteristic. Although adenovirus infection of guinea pigs has not previously been reported, histological findings paralleled those found in adenovirus infections of other animals including man. Virus particles found by electron-microscopical examination of the lung tissue closely resembled adenoviruses. The disease seemed to have a low contagiousness, a low morbidity (about 0.7%), but an acute course and a high mortality (100%).