BRAIN ABSCESS DUE TO PSEUDOMONAS PSEUDOMALLEI

Abstract A brain abscess due to Pseudomonas pseudomallei is presented. Central nervous system involvement in melioidosis is rare and generally occurs in association with disseminated infection. The importance of early diagnosis and prompt treatment with prolonged antibiotic therapy is emphasised.     

Splenobronchial fistula: Interventional radiologic management

A 71-year-old man had a splenic abscess complicated by rupture into the left subphrenic space with formation of a splenobronchial fistula. One percutaneous catheter was placed into the splenic abscess and a second was placed in the subphrenic collection. The abscesses resolved and the bronchial fistula closed in 12 days.     

结核杆菌多价核酸疫苗的构建及其免疫原性的初步研究

目的构建包含结核杆菌3种抗原蛋白Ag85A、ESAT-6和CFP-10真核表达质粒的多价DNA疫苗,并对其在小鼠体内的免疫原性进行初步分析。方法PCR扩增获得结核杆菌ag85 a、esat-6和cfp-10基因片段,分别克隆入真核表达质粒VR1020的BamHⅠ位点构建DNA疫苗,以此多价DNA疫苗免疫BALB/c小鼠,检测小鼠体内的特异性抗体应答和细胞免疫反应,并与BCG免疫组、质粒VR1020免疫组和生理盐水对照组相比较。结果多价DNA疫苗免疫小鼠后能产生特异性的细胞和体液免疫应答,DNA疫苗免疫组小鼠脾细胞IFN-γ的表达量显著高于BCG免疫组,而DNA疫苗免疫组小鼠所产生的特异性抗体水平低于BCG免疫组。结论成功构建了结核杆菌多价DNA疫苗,免疫小鼠后检测到特异性细胞和体液免疫应答。     

艾滋病病毒与结核分枝杆菌双重感染对死亡的影响

目的 了解广西壮族自治区（广西）HIV及结核分枝杆菌（Mycobacterium tuberculosis,MTB）双重感染对死亡的影响,为有效控制HIV/MTB双重感染提供依据。方法 利用中国疾病预防控制信息系统的艾滋病综合防治信息系统和结核病防治数据系统,收集整理2011年广西HIV/MTB双重感染患者,采用跨系统和大数据串联分析方法,交叉核对艾滋病治疗、随访、综合信息以及结核病患者登记报告基本信息,明确HIV/MTB双重感染患者;用描述性流行病学方法、χ²检验以及Cox比例风险回归模型描述、分析资料。结果 HIV感染者及艾滋病患者登记队列（HIV/AIDS队列）感染MTB比例为17.72%（2 533/14 293）;结核病患者登记队列（结核病队列）感染HIV比例5.57%（2 351/42 205）;随访1年内HIV/AIDS队列发现的HIV/MTB双重感染患者病死率为15.16%（384/2 533）,高于单纯感染HIV者随访1年的病死率（13.63%,1 603/11 760）（P<0.000 1）;19.33%（384/1 987）当年登记、当年死亡的HIV/AIDS由感染MTB引起。HIV/AIDS队列和结核病队列发现的双重感染分别有60.05%（1 521/2 533）、47.90%（1 126/2 351）开始抗病毒治疗;HIV/AIDS队列发现的结核病患者结核病治愈率为15.48%（392/2 533）,完成疗程比例为27.48%（696/2 533）;结核病队列发现的HIV/AIDS其结核病治愈率为19.70%（463/2 351）,完成疗程比例为37.26%（876/2 351）;64.13%（785/1 224）HIV/MTB双重感染报告时CD4⁺T淋巴细胞计数（CD4）<200个/μl。与单纯感染HIV者相比,HIV/MTB双重感染患者5年死亡风险增高1.17倍,和单纯感染MTB者相比,HIV/MTB双重感染者12个月死亡风险增加25.68倍。结论 广西HIV/MTB双重感染死亡、发病占报告艾滋病患者比例较高,病死率及死亡风险明显高于单纯感染HIV者及单纯感染MTB者;应该尽快提高抗病毒治疗覆盖率和抗结核治愈率;针对HIV感染者,应加强早发现和早治疗MTB感染。     

Effect of reactive oxygen intermediaries on the viability and infectivity of Mycobacterium lepraemurium

Murine leprosy is a natural disease of the mouse, the most popular model animal used in biomedical research; the disease is caused by Mycobacterium lepraemurium (MLM), a successful parasite of macrophages. The aim of the study was to test the hypothesis that MLM survives within macrophages because it highly resists the toxic effects of the reactive oxygen intermediaries produced by these cells in response to infection by the microorganism. MLM cells were incubated in the presence of horseradish peroxidase (HRPO)-H(2)O(2)-halide for several periods of time. The peroxidative effect of this system was investigated by assessing the changes occurred in (a) lipid composition; (b) viability; and (c) infectivity of the microorganism. Changes in the lipid composition of peroxidated- vs. intact-MLM were analysed by thin layer chromatography. The effect of the peroxidative system on the viability and infectivity of MLM was measured by the alamar blue reduction assay and by its ability to produce an infection in the mouse, respectively. Peroxidation of MLM produced drastic changes in the lipid envelope of the microorganism, killed the bacteria and abolished their ability to produce an in vivo infection in the mouse. In vitro, MLM is highly susceptible to the noxious effects of the HRPO-H(2)O(2)-halide system. Although the lipid envelope of MLM might protect the microorganism from the peroxidative substances produced at 'physiological' concentrations in vivo, the success of MLM as a parasite of macrophages might rather obey for other reasons. The ability of MLM to enter macrophages without triggering these cells' oxidative response and the lack of granular MPO in mature macrophages might better explain its success as an intracellular parasite of these cells.     

Ongoing genome reduction in Mycobacterium ulcerans

Elucidation of the transmission, epidemiology, and evolution of Mycobacterium ulcerans, the causative agent of Buruli ulcer, is hampered by the striking lack of genetic diversity of this emerging pathogen. However, by using a prototype plasmid-based microarray that covered 10% of the genome, we found multiple genomic DNA deletions among 30 M. ulcerans clinical isolates of diverse geographic origins. Many of the changes appear to have been mediated by insertion sequence (IS) elements IS2404 and IS2606, which have high copy numbers. Classification of the deleted genes according to their biological functions supports the hypothesis that M. ulcerans has recently evolved from the generalist environmental M. marinum to become a niche-adapted specialist. The substantial genomic diversity, along with a prototype microarray that covered a small portion of the genome, suggests that a genome-wide microarray will make available a genetic fingerprinting method with the high resolution required for microepidemiologic studies.     

Screening for tuberculosis among 2381 household contacts of sputum-smear-positive cases in The Gambia

Contact investigation is a key component of tuberculosis (TB) control in developed, but not developing, countries. We aimed to measure the prevalence of TB among household contacts of sputum-smear-positive TB cases in The Gambia and to assess the sensitivity of an enzyme-linked immunospot (ELISPOT) assay in this regard. Household contacts of adult smear-positive TB patients were assessed by questionnaire, purified protein derivative (PPD) skin test, ELISPOT assay, physical examination, chest X-ray and sputum/gastric aspirate. Thirty-three TB cases were identified from 2174 of 2381 contacts of 317 adult smear-positive pulmonary TB patients, giving a prevalence of 1518/100000. The cases identified tended to have milder disease than those passively detected. The sensitivity of ESAT-6/CFP-10 ELISPOT test as a screening test for TB disease was estimated as 71%. Fifty-six per cent of contacts with a PPD skin test result >or=10mm induration had detectable responses to ESAT-6/CFP-10 by ELISPOT; 11% with a negative PPD skin test (<10mm) had a positive ESAT-6/CFP-10 response. Active screening for TB among contacts of TB patients may have a role in TB control in The Gambia. These individuals are a high-risk group, and the disease identified is less advanced than that found through passive case detection. An ELISPOT assay was relatively insensitive as a screening test for TB.