Ocular toxoplasmosis in the immunocompromised host

Disseminated toxoplasmosis is a well-known complication of immunodeficiency states, including those induced by malignancies, steroid and cytotoxic drug therapy, and AIDS. In immunodeficient patients, toxoplasmic infections of the eye are less common than toxoplasmic infections of other organs for unknown reasons. When ocular toxoplasmosis does occur in the immunodeficient host, or if immunosuppressive therapy is administered to patients with active disease, widespread tissue destruction by proliferating organisms may result. Immunodeficiency alone may not be sufficient, however, to cause reactivation of encysted organisms in retinochoroidal scars.Ocular toxoplasmosis in the immunocompromised host presents difficult problems in diagnosis and management. There may be a variety of clinical lesions, including single foci of retinochoroiditis in one or both eyes, multifocal lesions, or diffuse areas of retinal necrosis. The majority of lesions do not arise from the borders of preexisting scars, which suggests that they result from acquired infection or dissemination of organisms from nonocular sites of disease.Toxoplasma gondii may infect iris, choroid, and vitreous-tissues that are not usually infected in the immunocompetent host. Ocular lesions appear to respond to standard antiparasitic drug therapies, but continued treatment is probably necessary to prevent reactivation of disease in the most immunocompromised patients. The best treatment regimens have yet to be determined. Histopathologic studies show little retinal inflammation; therefore anti-inflammatory drugs, such as oral steroids, probably have no role in the management of infection.     

卢湾区人体重要寄生虫感染调查

目的了解卢湾区居民寄生虫感染情况,为今后中心城区开展寄生虫病防治提供科学依据。方法采用改良加滕厚涂片法查肠道蠕虫卵,抗原皮内实验查肺吸虫,用ELISA方法查弓形虫和丝虫短程抗体,间接免疫荧光法(IFA)查隐孢子虫感染。结果肠道寄生虫感染率0.44%,肺吸虫皮试阳性率0.84%,孕妇弓形虫抗体阳性率2.85%,隐孢子虫感染率4.80%,丝虫抗体阳性率0.32%。结论中心城区存在各种寄生虫感染,针对各种寄生虫感染途径积极开展寄生虫病健康教育,对防治寄生虫病具有重要意义。     

Immunopathology of intestinal helminth infection

The relationship between intestinal pathology and immune expulsion of gastrointestinal nematodes remains controversial. Parasite expulsion is associated with intestinal pathology in several model systems and both of these phenomena are T cell dependent. However, while immune expulsion of gastrointestinal helminth parasites is usually associated with Th2 responses, the effector mechanisms directly responsible for parasite loss have not been elucidated. In contrast, the intestinal pathology observed in many other disease models closely resembles that seen in helminth infections, but has been attributed to Th1 cytokines. We have used infection with the nematode Trichinella spiralis in mice defective for cytokines to demonstrate that although parasite expulsion is indeed IL-4 dependent, contrary to expectations, the enteropathy is also regulated by IL-4. Furthermore, abrogation of severe pathology in iNOS deficient and TNF receptor defective animals does not prevent parasite expulsion. TNF and iNOS are therefore involved in intestinal pathology in nematode infections, apparently under regulation by IL-4 and Th2 mediated responses. Therefore, it appears that the IL-4-dependent protective response against the parasite operates by a mechanism other than merely the gross degradation of the parasite's environment brought about by the immune enteropathy. However, it remains important to elucidate the protective mechanisms involved in parasite expulsion, which are still unclear.     

2002～2003年广西儿童人体重要寄生虫感染调查

目的了解广西儿童人体重要寄生虫病的感染现状及影响因素，为行政部门制定可行的防治对策提供依据。方法按《全国人体重要寄生虫病调查方案》的方法。结果14岁以下少年儿童人群寄生虫总感率46．42％，各种寄生虫感染率分别为：蛔虫30．99％、鞭虫14．70％、钩虫6．37％，华支睾吸虫0．56％，蛲虫感染率19．82％；以轻度、单一虫种感染为主；不同片区总感染率从高到低依次为东、南、西、中、北；瑶族感染率明显高于其它民族。结论广西少年儿童寄生虫感染较普遍，某些地区较严重。应重视群体性药物防治、粪便的无害化管理、生活环境改善、健康教育等工作，才能有效控制寄生虫病。     

A hydatid cyst in an unusual location—The infratemporal fossa

Hydatid disease is a considerable health problem worldwide, but hydatid cysts in the infratemporal region are extremely rare, even where the parasite is endemic. Here we report on a 17‐year‐old female who presented with a benign swelling in the infratemporal fossa. During surgery a cystic mass was discovered and histopathologic examination confirmed the diagnosis of a hydatid cyst. Although rare, a hydatid cyst should be considered in a differential diagnosis of benign swellings in the maxillofacial region. Physicians should exercise a high index of suspicion even in nonendemic locations.     

Molecular insights into trypanothione reductase‐inhibitor interaction: A structure‐based review

Information on how small molecules bind to the target enzyme has the potential to impact immensely on how medicinal chemists go about antiparasitic drug discovery. In this review, for the first time, we intend to make an assessment of the structural aspects of trypanothione reductase as drug target, and its complexes with several reversible drugs from the Protein Data Bank (PDB). We attempt to reveal the mechanism of these interactions by careful accounting of the X‐ray structures and their possible roles in biological activity to treat Trypanosomatidae diseases. We focus on some of the outstanding findings from structures that are relevant to anti‐trypanocidal drug discovery. We also review new interesting compounds that have appeared in the literature based on these X‐ray structures.

     

XS-1000i血液分析仪异常嗜酸性粒细胞散点图对疟原虫感染的提示作用

目的利用血液分析仪提示的嗜酸性粒细胞（eosinophil，EO）增高及异常散点图信息，结合显微镜镜检检出疟原虫。方法用XS-1000i血液分析仪进行血常规检测，对仪器报警提示嗜酸粒性细胞比值增高（EO＋）的标本用显微镜进行涂片检查，当发现E0无异常时，则镜检红细胞，查找疟原虫。结果在289例仪器报警提示EO＋增高的标本中，显微镜镜检发现有3例EO结果正常与仪器报警不符，这3例标本均在红细胞中检出疟原虫的滋养体、裂殖体或配殖体。结论在用Sysmex XS—1000i血液分析仪进行血常规检测时，若仪器提示“EO＋”而未得到显微镜镜检证实，则高度提示有疟原虫存在的可能性。     

河南省燕山-太行山生态区2015年人体肠道寄生虫感染现状调查

目的 了解河南省燕山-太行山生态区肠道寄生虫病的流行现状,为本地区肠道寄生虫感染的防治提供科学依据。方法 2014年11月—2015年6月按照经济条件和地理方位进行分层整群抽样,随机选择林州市、获嘉县、辉县市、孟州市、温县、沁阳市、博爱县、修武县和济源市等9个县(市)26个调查点,采集人群粪样,采用改良加藤厚涂片法检查肠道蠕虫感染情况,钩蚴试管滤纸培养法鉴别钩虫虫种,3~6岁儿童采用透明胶纸肛拭法检查蛲虫感染情况,碘液染色法检查肠道原虫感染情况。结果 共收集粪样6 754份,检出肠道蠕虫4种,肠道原虫4种。肠道寄生虫总感染率为1.48%(100/6 754),肠道蠕虫总感染率为1.02% (69/6 754),肠道原虫总感染率为0.47%(32/6 754)。3~6岁儿童蛲虫感染率为6.09%(37/608)。钩蚴经鉴定均为十二指肠钩虫。肠道寄生虫感染率最高的3个县分别是博爱县3.82%、济源市2.51%和获嘉县2.40%。男性和女性肠道寄生虫感染率分别为1.54%(49/3 178)和1.43% (51/3 576),差异无统计学意义(P>0.05)。不同文化程度人群中,肠道寄生虫感染率较高的为大专及以上组3.75%(3/80)和文盲组3.75%(37/986),与其他组相比,差异有统计学意义(P<0.05)。0~4岁和5~9岁人群肠道寄生虫感染率较高,分别为2.59%(13/502)和4.38%(29/662),两者之间差异无统计学意义(P>0.05),但与其他年龄组相比,差异有统计学意义(P<0.01)。各职业肠道寄生虫感染率由高到低依次为学龄前4.56%(36/789)、其他职业1.88%(7/373)、学生1.57%(16/1 016)和农民0.89%(41/4 576),差异有统计学意义(P<0.01)。结论 河南省燕山-太行山生态区人体重点寄生虫感染情况较前两次调查有显著下降,学龄前儿童和学生是今后监测的重点人群。     

Evaluation of Loop-mediated Isothermal Amplification Assay for Rapid Diagnosis of Acanthamoeba Keratitis

Background: The clinical features of Acanthamoeba keratitis (AK) are non-specific and closely resemble bacterial, viral and fungal keratitis. Materials and Methods: We compared loop-mediated isothermal amplification (LAMP) with microscopy, non-nutrient agar (NNA) culture and polymerase chain reaction (PCR) in clinical suspects of AK. Results: Of 52 clinical samples (42 AK suspects and 10 proven bacterial, viral or fungal keratitis), 3 were positive by direct microscopy (sensitivity 60%, confidence interval [CI]: 17%–92.7%), and 5 by NNA culture, 18S rDNA PCR and LAMP (sensitivity 100%, CI: 46.3%–100%). The limit of detection of Acanthamoeba DNA was 1 pg/μl by both LAMP and PCR. Conclusion: PCR and LAMP assays targeting 18S rDNA gene were found particularly suitable for a rapid and accurate diagnosis of AK. LAMP assay takes 2–3 h lesser than PCR, and thus offers a rapid, highly sensitive and specific, simple and affordable diagnostic modality for patients suspected of AK, especially in resource limited settings