Two genes for chloramphenicol resistance common to Staphylococci and streptococci

Southern blot hybridization and pneumococcal transformation were used to study the epidemiology at a molecular level of the genes for chloramphenicol resistance (cat) in streptococci and staphylococci. The cat gene of staphylococcal plasmid pC194 showed homology to the cat genes of the chromosomal elements of 5 different strains of Streptococcus pneumoniae and of Streptococcus agalactiae B109. DNA sequence homology was also detected between the cat gene of staphylococcal plasmid pC221 and the cat gene of broad host range conjugative plasmid pIP501, originally isolated from S. agalactiae. Two different cat genes appear to be present in clinical isolates of both streptococci and staphylococci.     

Viridans group streptococci: a reservoir of resistant bacteria in oral cavities

The worldwide spread of erythromycin A-resistant streptococci, including Streptococcus pneumoniae , is of concern. Many studies have demonstrated that the viridans group streptococci can be a reservoir of erythromycin A resistance. Within oral streptoccoci, an important difference in the susceptibility pattern has been noted. The purpose of this short editorial is to highlight the importance of this group of bacteria as a reservoir of resistance to erythromycin A and the possible transfer of resistance to S. pneumoniae and S. pyogenes.     

1,6-二磷酸果糖治疗婴幼儿肺炎心衰疗效观察

应用脉冲多普勒超声心动图对３０例使用１，６－二磷酸果糖的肺炎心衰患儿进行心室舒缩功能指标的观测，并以２０例常规治疗的心衰患儿及２０例正常儿为对照组，评价１，６－二磷酸果糖的疗效。结果表明，１，６－二磷酸果糖能明显改善ＰＥＰ、ＰＥＰ／ＥＴ、ＰＥＰ／Ｒ－Ｒ、ＦＶＩ和ＳＶ等心室收缩功能指标及ＰＦＶＥ、Ｅ／Ａ、ＰＦＶＡ等心室舒张功能指标，使心功能恢复正常。１，６－二磷酸果糖对肺炎心衰引起的心肌缺血、缺氧有保护作用。     

重症肺炎患者中性粒细胞胞吐作用的改变

目的　研究重症肺炎患者中性粒细胞的功能改变。方法　采用免疫化学法测定 32例重症肺炎患者中性粒细胞胞吐作用和氧化酶反应的变化 ,并与健康对照组比较。结果　重症肺炎患者血液中性粒细胞的基础和PMA刺激的胞吐作用均明显下降 (P <0 .0 1) ;重症肺炎患者的基础和PMA刺激的反应性氧属 (ROS)产生明显增加 ;重症肺炎患者肺部中性粒细胞释放乳铁蛋白、髓过氧化物酶 (MPO)和ROS增加 ,PMA刺激后相似 ;肺炎的严重性与血液中性粒细胞释放乳铁蛋白呈负相关。结论　重症肺炎患者中性粒细胞胞吐作用明显受损 ,与预后相关。     

糖尿病合并肺炎患者支气管肺泡灌洗液细胞学分析

目的评价糖尿病合并肺炎病人抗生素治疗2周后支气管肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中细胞学成分的特点,并与非糖尿病的肺炎病人进行比较,了解病灶局部炎症反应及吸收与非糖尿病组有否区别。方法抗生素治疗2周行支气管肺泡灌洗,测定BALF中细胞数、分类及淋巴细胞亚群。复查胸部X光片,对比两组之间BALF中细胞成分及肺部阴影完全吸收占病人的百分比。结果抗炎治疗2周后,糖尿病合并肺炎病人虽然外周血WBC已经恢复正常,但BALF中中性粒细胞的比率明显高于非糖尿病肺炎组(分别为54.89±11.23;27.02±6.95,P<0.05),且淋巴细胞亚群中CD4、CD4/CD8(分别为20.69±5.56;65%)。也较非糖尿病肺炎病人低(43.22±11.03;96%,P<0.01),治疗2周后,非糖尿病肺炎组肺部阴影吸收率为68%,糖尿病合并肺炎组为43.5%(P>0.05)。结论抗生素治疗2周后糖尿病合并肺炎组肺部局部炎症反应仍然存在,肺部阴影有延迟吸收倾向。     

Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion

Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA₂ is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG₂ acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG₂ anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG₂ anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.     

支原体肺炎肺外损伤患儿T细胞亚群、IFNγ、TNFα的变化及意义

目的 探讨支原体肺炎肺外损伤患儿细胞免疫、细胞因子状况和胸腺肽的治疗效果。方法 采用流式细胞仪和酶标仪检测31例支原体肺炎肺外损伤组患儿急性期、恢复期血中CD3CD4、CD8、CD4／CD8干扰素γ（IFNγ）、肿瘤坏死因子α（TNFα水平，并与支原体肺炎组比较。结果 ①急性期支原体肺炎肺外损伤组和支原体肺炎组比较，CD3、CD4显著降低（P〈0．05），TNFα显著升高（P〈0．01），CD8、IFNγ无统计学意义（P〉0．05）；②支原体肺炎肺外损伤组急性期和4周后比较，CD3、CD4、IFNγ升高（P〈0．05），TNFα显著降低（P〈0．01），CD8无变化。用胸腺肽治疗患者以上指标变化更明显。结论 支原体肺炎肺外损伤患儿细胞免疫功能低于支原体肺炎患儿；细胞因子中TNFα早期升高，而IFNγ不明显；恢复期TNFα下降，而IFNγ升高明显。用胸腺肽治疗能缩短病程。     

Prognostic factors for early clinical failure in patients with severe community-acquired pneumonia

For patients with community-acquired pneumonia (CAP), clinical response during the first days of treatment is predictive of clinical outcome. As risk assessments can improve the efficiency of pneumonia management, a prospective cohort study to assess clinical, biochemical and microbiological predictors of early clinical failure was conducted in patients with severe CAP (pneumonia severity index score of >90 or according to the American Thoracic Society definition). Failure was assessed at day 3 and was defined as death, a need for mechanical ventilation, respiratory rate >25/min, PaO2 <55 mm Hg, oxygen saturation <90%, haemodynamic instability, temperature >38 degrees C or confusion. Of 260 patients, 80 (31%) had early clinical failure, associated mainly with a respiratory rate >25/minute (n = 34), oxygen saturation <90% (n = 28) and confusion (n = 20). In multivariate logistic regression analysis, failure was associated independently with altered mental state (OR 3.19, 95% CI 1.75-5.80), arterial PaH <7.35 mm Hg (OR 4.29, 95% CI 1.53-12.05) and PaO2 <60 mm Hg (OR 1.75, 95% CI 0.97-3.15). A history of heart failure was associated inversely with clinical failure (OR 0.30, 95% CI 0.10-0.96). Patients who failed to respond had a higher 28-day mortality rate and a longer hospital stay. It was concluded that routine clinical and biochemical information can be used to predict early clinical failure in patients with severe CAP.     

肺炎衣原体抗体效价与多发性硬化的相关性探讨

目的 探讨肺炎衣原体（Chlamydia pneumoniae）感染在多发性硬化（MS）发病和进展中的作用和致病机制。方法 选取急性期MS患者31例，缓解期MS患者28例及其他神经系统疾病患者30例，健康对照者30名，应用酶联免疫吸附试验测定患者和对照者血清及脑脊液中肺炎衣原体IgG和IgM抗体水平。结果 急性期MS组、缓解期MS组、其他神经系统疾病组和健康对照组的肺炎衣原体血清IgG分别为48．4％、35．7％、30．0％、23．3％；4组IgM抗体效价分别为12．9％、14．3％、20．0％、10．0％，总体比较差异无统计学意义（P〉0．05）；急性期MS组与其他神经系统疾病组的脑脊液IgG和IgM抗体效价分别为0、6．7％和0、0，差异无统计学意义（P〉0．05）。结论 肺炎衣原体的感染或重复感染与MS发病相关不紧密，可能仅为MS的伴随感染。