Comparison of bronchoscopic and non-bronchoscopic techniques for diagnosis of ventilator associated pneumonia

Background:

The diagnosis of ventilator associated pneumonia (VAP) remains a challenge because the clinical signs and symptoms lack both sensitivity and specificity and the selection of microbiologic diagnostic procedure is still a matter of debate.

Aims and Objective:

To study the role of various bronchoscopic and non-bronchoscopic diagnostic techniques for diagnosis of VAP.

Settings and Design:

This prospective comparative study was conducted in a medical ICU of a tertiary care center.

Materials and Methods:

Twenty-five patients, clinically diagnosed with VAP, were evaluated by bronchoscopic and non-bronchoscopic procedures for diagnosis. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of various bronchoscopic and non-bronchoscopic techniques were calculated, taking clinical pulmonary infection score (CPIS) of ≥6 as reference standard.

Results:

Our study has shown that for the diagnosis of VAP, bronchoscopic brush had a sensitivity, specificity, PPV and NPV of 94.9% [confidence interval (CI): 70.6–99.7], 57.1% (CI: 13.4–86.1), 85% (CI: 61.1–96) and 80% (CI: 21.9–98.7), respectively. Bronchoscopic bronchoalveolar lavage (BAL) had a sensitivity, specificity, PPV and NPV of 77.8% (CI: 51.9–92.6), 71.8% (CI: 24.1–94), 87.3% (CI: 60.4–97.8) and 55.5% (CI: 17.4–82.6), respectively. Sensitivity, specificity, PPV and NPV for non–bronchoscopic BAL (NBAL) were 83.3% (CI: 57.7–95.6), 71.43% (CI: 24.1–94), 88.2% (CI: 62.3–97.4) and 62.5% (CI: 20.2–88.2), respectively. Endotracheal aspirate (ETA) yield was only 52% and showed poor concordance with BAL (κ-0.351; P-0.064) and NBAL (k-0.272; P-0.161). There was a good microbiologic concordance among different bronchoscopic and non-bronchoscopic distal airway sampling techniques.

Conclusion:

NBAL is an inexpensive, easy, and useful technique for microbiologic diagnosis of VAP. Our findings, if verified, might simplify the approach for the diagnosis of VAP.     

肺泡灌洗术联合机械通气对老年重症哮喘患者临床症状及肺功能的影响

目的探讨肺泡灌洗术联合机械通气对老年重症哮喘患者临床症状及肺功能的影响。方法选择70例重症哮喘患者。随机分为观察组和对照组,观察组患者接受常规治疗联合肺泡灌洗术、机械通气治疗,对照组接受常规治疗联合机械通气治疗,比较2组患者临床症状、气道功能、炎症介质含量及治疗效果。结果观察组有效率为94.29%,显著高于对照组77.14%(P0.05);观察组患者临床症状改善时间、机械通气时间、ICU住院时间均显著短于对照组(P0.05);观察组患者FEV1、FVC、FEV1/FVC%均显著高于对照组(P0.05);观察组患者的CRP、TNF-α、IL-6含量均显著低于对照组(P0.05)。结论肺泡灌洗术联合机械通气治疗有助于改善临床症状和肺功能,缓解炎症反应,提高治疗效果。     

支气管肺泡灌洗在治疗重症哮喘患者中的效果观察及护理

目的 探讨支气管肺泡灌洗在治疗重症哮喘患者中的治疗效果及护理经验.方法 对24例重症哮喘患者在机械通气的基础上采用纤支镜支气管肺泡灌洗治疗,观察和比较支气管肺泡灌洗前后患者动脉血气及气道阻力变化情况和观察灌洗过程中不良反应及并发症发生情况.结果 支气管肺泡灌洗后患者动脉氧分压( PaO2)、血氧饱和度(SaO2)较灌洗前升高,气道峰压(PIP)较灌洗前降低,灌洗前后比较,均P＜0.01,差异具有统计学意义;在灌洗过程中患者未出现严重的并发症.结论 在机械通气的基础上采用纤支镜下支气管肺泡灌洗是治疗重症哮喘有效手段.做好灌洗前后的护理是保证治疗成功的关键.     

下呼吸道支气管肺泡灌洗液病原菌种类及耐药分析

目的对支气管肺泡灌洗液（BALF）进行培养,以分析引起肺部感染的病原菌种类及其对抗菌药物的耐药情况。方法 2009年1月至2011年10月222份BALF标本共分离出80株病原菌,对80株BALF培养的病原菌种类及其耐药结果进行回顾性分析。结果 BALF阳性率36%,其中革兰阴性菌占56.25%,革兰阳性菌占25.00%,真菌占18.75%;药敏结果显示革兰阴性杆菌对亚胺培南、美诺培南、头孢他啶、头孢吡肟、阿米卡星、哌拉西林/三唑巴坦、替卡西林/克拉维酸敏感性高,革兰阳性球菌对替考拉宁、万古霉素耐药率为0,真菌对常用抗真菌药如5-氟胞嘧啶、两性霉素B、氟康唑、伊曲康唑、伏立康唑敏感性高。结论 BALF培养的致病菌以革兰阴性菌为主,要重视BALF结核分枝杆菌培养,培养结果可对诊断肺部感染和抗菌药物目标性治疗提供确信的科学依据。     

Expression of Th1 markers by lung accumulated T cells in pulmonary sarcoidosis

OBJECTIVES: The balance between Th1 and Th2 T cells, classified by virtue of their cytokine production can in an immune response influence the phenotype and progression of several clinical diseases. In this study, we examined the expression of Th1 associated chemokine and cytokine receptors CXCR3, CCR5, and interleukin (IL)-12R, IL-18R, respectively, as well as of the Th2 associated chemokine receptors CCR4 and CXCR4 on CD4+ and CD8+ T cells. SUBJECTS: Eighteen patients with untreated pulmonary sarcoidosis. MATERIALS AND METHODS: We used monoclonal antibodies and flow cytometry to analyse the expression of chemokine receptors CXCR3, CXCR4, CCR4 CCR5 and cytokine receptors IL-12R, IL-18R in combination with anti-CD4 and anti-CD8 mAbs in bronchoalveolar lavage fluid (BAL) and peripheral blood lymphocytes (PBL) from sarcoidosis patients. RESULTS: There were significantly more BAL CD4+ T cells expressing CXCR3, CCR5, IL-12R and IL-18R compared with paired PBL CD4+ T cells. In contrast, the Th2 associated chemokine receptors CXCR4 and CCR4 were expressed by a fewer percentage of BAL CD4+ compared with PBL CD4+ T cells. There was a positive correlation between the percentage of BAL lymphocytes and the number of CXCR3 and CCR5 expressing CD4+ BAL T cells. Also, the number of CD4+ IL-18R+ BAL fluid cells correlated negatively with disease duration. CONCLUSIONS: The lung accumulation of CXCR3, CCR5, IL-12R and IL-18R expressing T cells is in line with previous reports showing elevated levels in the lung of the corresponding ligands in sarcodosis. Blocking such ligands and/or receptors may develop into a future immunomodulatory therapy.     

Polymorphism in RANTES chemokine promoter affects extent of sarcoidosis in a Japanese population

RANTES, a member of C-C chemokine, is known to be produced at sites of granulomatous reactions in the lung of sarcoidosis. RANTES is a potent eosinophil and lymphocyte attractant with particular preference for CD45RO+ T cells and eosinophils. Polymorphism of the RANTES promoter has recently been shown to be related to allergic and infectious diseases; atopic dermatitis, asthma, and polymyalgia rheumatica. Considering that this might affect sarcoidosis, we studied polymorphism of the RANTES gene in 114 patients with sarcoidosis and 136 healthy control subjects. Their genotypes were determined using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Although no difference in the genotype distribution between healthy control subjects and sarcoidosis patients was identified, the difference in the frequencies of the patients with three or more organ involvement was significant (P<0.01) with the frequency of those in AA genotype being elevated (P<0.05). BAL findings in 48 out of 114 patients who underwent bronchoscopy were reviewed. The CD4/8 ratio of lymphocytes in bronchoalveolar lavage fluid in the patients with AA genotype was significantly increased (P<0.05). From the results, we suggest that in RANTES gene polymorphism the homozygous A allele might be a genetic risk factor for extent disease of sarcoidosis.     

疏风通络方对哮喘大鼠不同时相外周血和肺泡灌洗液嗜酸细胞数量变化的影响

目的：探讨疏风通络方对哮喘大鼠血液和肺泡灌洗液（BALF）嗜酸细胞（EOS）数量变化的影响。方法：选择SPF级雄性Wistar大鼠为研究对象,随机分为正常组、模型组、氟美松组、DPI组、中药低、中、高剂量组,共7组,每组大鼠36只。第1d致敏：正常组给予生理盐水1mL代替抗原腹腔注射致敏,而其他6组给予1mL造模液（含Ⅴ级卵清蛋白100mg,氢氧化铝100mg和灭活百日咳杆菌6×10^9个）腹腔注射致敏;第15d开始激发：将各组大鼠分别置于相同大小的雾化箱内,正常组给予生理盐水6mL雾化激发,其他6组给予5％的Ⅴ级卵清蛋白（OVA）溶液6mL雾化激发,每次激发前2h正常组给予生理盐水1mL灌胃,而其他6组给予相应的药物灌胃。各组每天激发1次,每次激发30min,连续激发10d。距首次激发后的0h、6h、12h、24h、72h、10d各时点分别麻醉下每组取6只大鼠心脏采血和肺泡灌洗（取材结束后大鼠失血死亡）,然后迅速对血液和BALF标本进行EOS数量检测。结果：血中EOS数量变化：在不同时点模型组均高于正常组（P〈0．001）;各治疗组与模型组相比,氟美松组在0h、6h、12h、10d时点处于最低（P〈0．01或P〈0．001）,DPI组在24h、72h时点处于最低,但二者之间比较没有显著差异（P〉0．05）;其他治疗组之间相比,0—72h各时点DPI组处于最低（P〈0．001）,在10d时点中药高剂量组处于最低,且优于DPI组（P〈0．01）。BALF中EOS数量：在0h时点各组之间没有显著变化（P〉0．05）;在6h时除中药高剂量组外,模型组与其他治疗组和正常组之间均没有差异（P〉0．05）;在12h时点除模型组较正常组显著上升（P〈0．05）,各治疗组与模型组之间及各治疗组之间均没有差异（P〉0．05）;在24h时点,模型组显著高于正常组（P〈0．01）,各治疗组与模型组比较,只有氟美松有显著差异（P〈0．01）;在72h、10d时点模型组均显著高于正常组（P〈0．001）,DPI组和中药低剂量组与模型组比较均没有差异（P〉0．05）,氟美松组、中药中、高剂量组均与模型组比较有显著差异（P〈0．05或P〈0．01或P〈0．001）,三者比较,氟美松组EOS数值最低,中药中、高剂量组之间比较没有显著差异（P〉0．05）。结论：氟美松对哮喘大鼠血和BALF中EOS数量的影响最大,能显著降低血和BALF中EOS数量,而中药疏风通络方起效、显效慢,效果始终不及氟美松。     

咳嗽变异型哮喘多项检测指标的Bayes判别分析

目的探讨咳嗽变异型哮喘（CVA）肺功能、气道弹性阻力、支气管激发试验、最大呼气峰流量（PEF）日内波动率[△PEFR（％）]、支气管肺泡灌洗液（BALF）细胞学以及血清IgE的变化特点及诊断意义。方法对22例CVA、20例慢性阻塞性肺病（COPD）稳定期患者以及20名健康成年人进行最大呼气流量-容积曲线（MEFV曲线）、气道弹性阻力、支气管激发试验、[△PEFR（％）]、BALF细胞学分析以及血清IgE测定。结果（1）CVA患者呼气流量指标[PEF、一秒用力呼气容积（FEV1）、FEV,／FVC、最大呼气中段流量（MMEF）]与健康对照组比较差异无统计学意义（P〉0．05）。CVA组气道弹性阻力增高,与健康对照组比较差异有统计学意义（P〈0．01）,但与COPD组比较差异无统计学意义（P〉0．05）;（2）CVA组患者气道反应性明显增高,支气管激发试验阳性,Mch—PC20-FEV1明显降低、[APEFR（％）]增大（〉20％）、BALF中嗜酸性粒细胞明显增高、血清IgE明显增高与健康对照组及COPD组比较差异有统计学意义（均P〈0．01）。结论气道弹性阻力、支气管激发试验、[APEFR（％）]、BALF细胞学以及血清IgE的测定有助于CVA的诊断且与COPD等的鉴别。根据Bayes判别结果,鉴别CVA与COPD的上述病因学指标作用大小依次为Mch—PC20-FEV1、JgE、[△PEFR（％）]、BALF嗜酸性粒细胞计数、FEV1／FVC、FEV1、PEF、MMEF和气道弹性阻力,其中主要为Mch—PC20-FEV1、IgE、[APEFR（％）]、BALF嗜酸性粒细胞计数。     

纤维支气管镜支气管肺泡灌洗术治疗重症肺部感染临床研究

目的：探讨纤维支气管镜（简称纤支镜）肺泡灌洗术在治疗肺部感染性疾病的疗效。方法：共从内科系统中入选社区获得性肺炎和医院获得性肺炎患者122例,将其分为二组,治疗组：传统治疗加纤支镜肺泡灌洗术治疗肺部感染,共52例;对照组：传统方法治疗肺部感染,共70例。结果：两组病例在发热时间,咳嗽,咳痰及肺部罗音消失时间,住院日,抗生素使用时间,治愈率和死亡率方面对比均有显著性差异（P〈0.05）。结论：纤支镜肺泡灌洗术在治疗肺部感染性疾病的疗效确切,且术中危险性小,值得推广。     

Human airway and peripheral blood eosinophils enhance Th1 and Th2 cytokine secretion

BACKGROUND: The effector function of eosinophils involves their release of toxic granule proteins, reactive oxygen species, cytokines, and lipid mediators. Murine studies have demonstrated that eosinophils can also enhance T cell function. Whether human eosinophils, in particular, airway eosinophils, have similar immunoregulatory activity has not been fully investigated. The aim of this study was to determine whether human blood and airway eosinophils can contribute to Th1 and Th2 cytokine generation from CD4+ T cells stimulated with superantigen. METHODS: Eosinophils were obtained from blood or bronchoalveolar lavage fluid 48 h after segmental allergen bronchoprovocation. Purified eosinophils were co-cultured with autologous CD4+ blood T cells in the presence of staphylococcal enterotoxin B (SEB). Cytokine levels in the supernatant fluid were determined by enzyme-linked immunosorbent assay (ELISA). Eosinophil expression of major histocompatibility complex (MHC) class II and co-stimulatory molecules was assessed by flow cytometry before culture, 24 h after granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation, and 24 h after co-culture with CD4+ T cells and SEB. RESULTS: Interleukin (IL)-5, IL-13, and interferon (IFN)-gamma generation increased when CD4+ T cells were co-cultured with either blood or airway eosinophils in the presence of SEB. The ability of eosinophils to enhance cytokine generation was independent of their source (blood vs airway), activation by GM-CSF, or detectable expression of human leukocyte antigen (HLA)-DR, CD80, or CD86. CONCLUSION: Our data demonstrate that SEB-induced generation of Th1 and Th2 cytokines is increased in the presence of human blood and airway eosinophils. Thus, eosinophils can have an immunoregulatory function in pathogen-associated allergic diseases such as atopic dermatitis, chronic sinusitis, and asthma exacerbations.