弓形虫病诊断方法的对比研究

应用５种不同方法测定了６例弓形虫病人不同病期的血清标本。用ＩＨＡＴ和ＩＦＡＴ测定弓形虫总免疫球蛋白，ＥＨＡＴ在发病后第３周的２份血清标本中有１份已呈阳性，１４－１７周达高峰。滴度升高非常明显；ＩＦＡＴ第３周的标本都呈阳性；１７－２４周达高峰。用ＩｇＧ－ＥＬＩＳＡ和ＩｇＭ－ＥＬＩＳＡ，ＩｇＭ－ＩＦＡＴ分别测定抗弓形虫特异性抗体ＩｇＧ和ＩｇＭ＜ＩｇＧ－ＥＬＩＳ从第６周呈阳性，随病情延长，滴度明显升高，     

四种弓形虫病血清学诊断方法的比较研究

本研究应用弓形虫的斑点酶联免疫吸附试验（Ｄｏｔ－ＥＬＩＳＡ）、常规酶联免疫吸附试验（ＥＬＩＳＡ）和间接免疫荧光试验（ＩＦＡ）及间接血凝抑制试验（ＩＨＡ）四种方法，分别检测了同一批人血清（１５０份）。结果表明：（１）四种方法中以Ｄｏｔ－ＥＬＩＳＡ最为敏感，血清阳性检出率最高为１９．３％；ＩＦＡ次之为１１．３％；ＥＬＩＳＡ为８．６９％；ＩＨＡ最低仅为６．６６％。（２）Ｄｏｔ－ＥＬＩＳＡ明显优于常规ＥＬ     

DIFA等四项免疫学方法检测血吸虫病合并弓形虫感染的研究

弓形虫ＩＨＡ和ＥＬＩＳＡ对急性血吸虫病有严重的交叉反应，影响弓形虫病的临床诊断。本文用ＤＩ－ＦＡ、ＩＦＴ、ＩＳＡＧＡ－ＩｇＧ和ＩＨＡ检测６６例急性血吸虫病，结果其阳性率分别为１９．７０％、２２．７３％、１６．６７％和６５．１６％；用ＤＩＦＡ和ＩＦＴ检测健康人群的弓形体阳性率为９％；还用上述方法检测两种病的混合血清和兔急性血吸虫病血清。通过比较、分析认为前三种方法可用于两病的鉴别。本文还用上述方法检测２１例慢性血吸虫病，阳性率在０～１９．０５％之间，无明显血清交叉反应。     

多项免疫吸附凝集试验检测孕妇弓形虫感染的实验研究

用弓形虫ＩｇＧ／ＩｇＡ／ＩｇＭ免疫吸附凝集试验检测５０７份孕妇血清，并与ＤＡ、ＳＦＴ、ＩＳＡＧＡ－ＩｇＭＥＩＡ－ＩｇＭ多项方法检测结果比较分析。多项检测结果阴性的２０１份血清中，该法检测出ＩｇＧ阳性２１份，ＩｇＡ、ＩｇＭ均为阴性，较ＤＡ敏感；多项检测结果为非活动性弓形虫感染的２０３份血清中，该法检出ＩｇＧ阳性１９７份、ＩｇＡ阳性１１份、ＩｇＭ阳性４份，阳性率分别为９７．０５％、５．４１％、１．９７％两者结果基本相符；多项检测结果为活动性感染的１０３份血清中，该法检出ＩｇＭ阳性８７份，ＩｇＡ阳性６１份，ＩｇＧ阳性１０３份，其中ＩｇＭ阳性与单项的ＩＳＡＧＡ－ＩｇＭ阳性结果相符率较高为８３．０２％。弓形虫ＩｇＧ／ＩｇＡ／ＩｇＭ免疫吸附凝集试验盒可作弓形虫感染的定性、定量检测，对判定孕妇的弓形虫感染时间是较好的方法。     

不同病型,病期HFRS患者特异性抗体水平测定及其临床意义

用捕获ＥＬＩＳＡ方法检测了６０例（１２０份）肾综合征出血热患者（ＨＦＲＳ）血清特异性ＩｇＡ、Ｉｇ－Ｅ、ＩｇＭ、ＩｇＧ抗体。发现４种抗体几何平均滴度均随病期进展逐渐升高，且早期（发热及休克少尿期）与后期（多尿恢复期）间有差异性。ＨＦＲＳ－ＩｇＭ、ＩｇＥ、ＩｇＧ抗体水平的差异在早期（特别是发热期）尤为显著（Ｐ＜０．０５）。结果显示，ＨＦＲＳ－ＩｇＭ确属早期较可靠诊断指标；ＨＦＲＳ－ＩｇＧ、ＩｇＥ抗体水平与病情严重度相关。ＨＦＲＳ－ＩｇＡ抗体可能是一种保护性抗体。     

斑点免疫金银染色与Dot—ELISA检测抗弓形虫抗体的对比研究

为比较斑点免疫金银染色（Ｄｏｔ－ＩＧＳＳ）和Ｄｏｔ－ＥＬＩＳＡ检测弓形虫抗体的敏感性和特异性，本实验以弓形虫速殖子可溶性蛋白抗原为诊断用抗原，同时用Ｄｏｔ－ＩＧＳＳ和Ｄｏｔ－ＥＬＩＳＡ检测６５份弓形虫感染者血清、１７６份其他寄生虫感染者血清和７６份对照血清。结果显示，用Ｄｏｔ－ＩＧＳＳ及Ｄｏｔ－ＥＬＩＳＡ检测弓形虫感染者抗体阳性率分别为９８．４６％及９２．３１％，平均抗体滴度分别为１：３８４及１：     

COMPARATIVE STUDY ON DETECTION OF ANTI-TOXOPLASM A GONDII ANTIBODIES BY USING DOT-ELISA AND DOT-IMMUNOGOLD SILVER STAINING

为比较斑点免疫金银染色（Ｄｏｔ－ＩＧＳＳ）和Ｄｏｔ－ＥＬＩＳＡ检测弓形虫抗体的敏感性和特异性，本实验以弓形虫速殖子可溶性蛋白抗原为诊断用抗原，同时用Ｄｏｔ－ＩＧＳＳ和Ｄｏｔ－ＥＬＩＳＡ检测６５份弓形虫感染者血清、１７６份其他寄生虫感染者血清和７６份对照血清。结果显示，用Ｄｏｔ－ＩＧＳＳ及Ｄｏｔ－ＥＬＩＳＡ检测弓形虫感染者抗体阳性率分别为９８．４６％及９２．３１％，平均抗体滴度分别为１∶３８４及１∶２１８（１∶２０－１∶２５６０）。用Ｄｏｔ－ＩＧＳＳ检测，有２３份血清抗体滴度高于Ｄｏｔ－ＥＬＩＳＡ，有８份低于Ｄｏｔ－ＥＬＩＳＡ。二种方法所测抗体滴度呈直线正相关关系（ｒ＝０．６０８，Ｐ＜０．０１）。二种方法检测其他寄生虫感染者和对照血清，假阳性率分别为５．９５％及１３．８９％。Ｄｏｔ－ＩＧＳＳ操作流程和Ｄｏｔ－ＥＬＩＳＡ相似，但敏感性、特异性均优于Ｄｏｔ－ＥＬＩＳＡ，前者不使用对人体有害的底物，有较好的推广前景。     

含弓形虫ROP1基因真核表达重组质粒DNA免疫小鼠的研究Ⅴ.IFN-γ基因真核表达重组质粒的构建及其在DNA免疫中基因佐剂的作用

目的　构建ＩＦＮ－γ基因真核表达重组质粒作为基因佐剂,观察其与ｐｃＤＮＡ３－ＲＯＰ１（ｐｃ－ＲＯＰ１） ＤＮＡ共同免疫小鼠所诱导的免疫应答。方法　将ＩＦＮ－γ基因片段定向插入真核表达载体ｐｃＤＮＡ３,双酶切鉴定,获得ｐｃＩＦＮ 重组子;碱裂解法大量制备,经肌肉注射免疫ＢＡＬＢ／ｃ小鼠,每只鼠注射ｐｃＩＦＮ、ｐｃ－ＲＯＰ１ 各１００μｇ,两周后同量加强免疫一次,以ｐｃＤＮＡ３空质粒及生理盐水组为对照。分别于免疫后第３０ 天、５０ 天、７０天共三次用ＭＴＴ法测定小鼠脾脏Ｔ淋巴细胞增殖活性及ＮＫ细胞活性;双夹心ＥＬＩＳＡ 测定血清细胞因子ＩＦＮ－γ、ＩＬ－２及酶法测定ＮＯ含量;ＥＬＩＳＡ法测定ＩｇＧ抗体滴度。结果　构建成功的作用下,该两项指标均明显提高,且ＩＦＮ－γ、ＩＬ－２ 及ＮＯ水平均较不加佐剂组显著提高（Ｐ＜ ０．０１）;而对ＩｇＧ抗体滴度无显著影响（Ｐ＞ ０．０５。结论　ＩＦＮ－γ基因佐剂具有协同ｐｃ－ＲＯＰ１ＤＮＡ免疫的作用,可增强免疫鼠细胞免疫应答,ＩＦＮ－γ、ＩＬ－２细胞因子及ＮＯ的产生     

应用PCR技术检测孕早期绒毛组织弓形虫DNA的研究

应用ＰＣＲ技术检测２７０例孕６－１２周妇女外周血及相应绒毛组织中的弓形虫ＤＮＡ，结果弓形虫ＤＮＡ阳性２６例，相应的绒毛组织中检出８例，垂直传播率为３０．７７％，同时用ＥＬＩＳ法检测血清中弓形虫循环抗原、ＩｇＭ和ＩｇＧ抗体，结果阳性率分别为３．７０％、７．０３％和１５．５％。ＩｇＭ和／或ＣＡｇ阳性者，外周血皆检出弓形虫ＤＮＡ。提示应用ＰＣＲ技术检测绒毛组织弓形虫ＤＮＡ结合ＥＬＩＳＡ进行筛选，可早期诊     

弓形虫病IgM免疫吸附凝集试验（ISAGA）的建立

目的∶建立检测弓形虫 Ｉｇ Ｍ 抗体的免疫吸附凝集试验 （ Ｉ Ｓ Ａ Ｇ Ａ） 。方法∶ Ｕ 型微孔板以适宜浓度的羊抗人 Ｉｇ Ｍ 抗体包被， 用１ ％ 牛血清白蛋白封闭， 洗板后加入待测血清， 在３７ ℃孵育后洗涤， 加入弓形虫（ Ｒ Ｈ 株） 速殖子抗原悬液， 置３７ ℃过夜后观察结果。将其与丹麦的 Ｉ Ｓ Ａ Ｇ Ａ 和 Ｅ Ｌ Ｉ Ｓ Ａ 检测的结果以及玻片 Ｅ Ｉ Ａ 检测的结果作比较。结果∶本法与丹麦的试验检测丹麦孕妇４４ 份血清， 总符合率为９３２ ％ ；与玻片 Ｅ Ｉ Ａ 检测丹麦和上海孕妇６７ 份血清， 总符合率为９２５ ％ ， 两法的滴度之间明显相关 （γ＝ ０５８９ ， Ｐ＜ ０００１） ， Ｉ Ｓ Ａ Ｇ Ａ 滴度较玻片 Ｅ Ｉ Ａ 高１８ 倍； 用 Ｗ Ｈ Ｏ 国际生物标准化实验室提供的标准的抗弓形虫人血清定量测得其灵敏度为００８ Ｉ Ｕ／ ｍｌ。结论∶ Ｉｇ Ｍ Ｉ Ｓ Ａ Ｇ Ａ 具有敏感性、特异性高， 操作简便等优点， 不仅可作为弓形虫急性感染和慢性感染活动期的一种检测手段， 而且适用于弓形虫感染调查的大规模筛选。     

ANTIBODY PATTERNS IN THE SEROLOGICAL DIAGNOSIS OF ACUTE LYMPHADENOPATHIC TOXOPLASMOSIS

Abstract Sera from six patients at various stages of acute lymphadenopathic toxoplasmosis were tested using nine different types of test currently available for the serological diagnosis of the disease. A diagnosis was made on positive serology in three of the patients. The antibody patterns of two of these patients were studied over a period of six months and the third was studied over two months. A diagnosis was made on lymph node morphology in the other three cases. Two serum samples were tested from each of these patients. The results obtained suggest that a rationalisation of the types of test used should be encouraged and that an enzyme-linked immunosorbent assay (ELISA) for parasite-specific IgG and an antibody class capture ELISA for parasite-specific IgM are sufficient to confirm the diagnosis of acute lymphadenopathic toxoplasmosis.     

Enzyme-linked immunosorbent assay for the diagnosis of clinical and subclinical melioidosis

An enzyme-linked immunosorbent assay (ELISA) for the detection of specific IgG and IgM antibody to Pseudomonas pseudomallei was developed. The IgG-ELISA was compared with the indirect fluorescence assay for IgG antibody (IgG-IFA) and the indirect hemagglutination (IHA) test in studies with serum specimens from persons from endemic areas for melioidosis and from persons from nonendemic areas of Australia. The sensitivity and specificity of the IgG-ELISA were 90% and 99%, respectively, comparable to those obtained with the IgG-IFA. The IgG-ELISA was more sensitive than the IHA test (74%) and was more suitable than the IgG-IFA as a serologic screening test for melioidosis. The IgM-ELISA was compared with the IgM-IFA as a marker of disease stage in patients with melioidosis. There was good diagnostic agreement between the tests; 92% of patients with active disease gave IgM-ELISA titers greater than or equal to 1:5,120 and 93% of patients with subclinical melioidosis had IgM-ELISA titers less than or equal to 1:1,280. Of the overlap group of patients with a borderline IgM-ELISA titer of 1:2,560, approximately 33% were clinical cases. An uncommon disease stage consisting of a self-limited, short-term, flu-like, pyrexial illness accompanied by elevated serum IgM-ELISA titers (greater than or equal to 1:5,120) was seen in a small number of patients residing in endemic Australia.     

Comparison of a slide agglutination test, LeptoTek Dri-Dot, and IgM-ELISA with microscopic agglutination test for Leptospira antibody detection

A slide agglutination test (SAT), LeptoTek Dri-Dot and IgM-ELISA were compared with a microscopic agglutination test (MAT) for the detection of Leptospira antibodies. Paired sera from 10 patients whose leptospirosis was clinically suspected and diagnosed by MAT, were evaluated in this study. Our data, especially from acute samples, demonstrate the SAT and Dri-Dot were more sensitive as initial screening tests than MAT. IgM-ELISA has an advantage over MAT, SAT, and Dri-Dot since the results can be interpreted from a single serum testing if the results of the test are positive. Eight of the ten cases could be diagnosed by IgM-ELISA. Our data suggest that IgM-ELISA may be used for the diagnosis of leptospirosis. However, the agglutination test is useful for screening and for secondary infection cases for which IgM antibodies may be undetectable. MAT can be performed as a reference test and when information regarding the causative serovar is required.     

Elevated Toxoplasma IgG antibody in patients tested for infectious mononucleosis in an urban emergency department

There are many infectious causes of fatigue, sore throat, and fever, including mononucleosis and toxoplasmosis. Toxoplasma antibody testing is rarely performed in most emergency departments; as a result, toxoplasmosis is diagnosed infrequently. We obtained Toxoplasma IgG IFA titers on ED patients who had mononucleosis testing performed to determine the frequency of toxoplasmosis in this population. Two hundred sixty patients were included in our study. Eleven (4.2%) had a positive mononucleosis test, and 14 (5.4%) had a positive Toxoplasma titer. In the detection of toxoplasmosis, Toxoplasma IgG titers of 1:1,024 or greater have been shown to be a sensitive means of detecting infection in the first six months. Further testing with IgM titers is needed to establish a positive diagnosis when necessary. We found more patients with elevated Toxoplasma IgG titers than with positive heterophil antibody titers in an ED population tested for mononucleosis over a two-year period. We conclude that toxoplasmosis may be as common as mononucleosis in our ED and that clinicians should consider this pathogen when working up patients with appropriate symptoms.     

Toxoplasmosis in hairy-cell leukaemia

Toxoplasma serology was performed in 28 patients with hairy-cell leukaemia and was positive in eight patients (29%). In two patients (7%) reactivated toxoplasmosis was proven by either isolation of Toxoplasma gondii or by significant antibody titre rise with generation of specific IgM-antibodies. In four patients (14%), a clinical diagnosis of active toxoplasmosis was based on signs and symptoms, serologic tests, and response to specific treatment. The high proportion of patients in which active toxoplasmosis was proven or probable (six; 21%) may be related to the presence of severe monocytopenia. In patients with hairy-cell leukaemia developing fever of unknown origin and myositis, toxoplasma serology should be performed, particularly because treatment of active toxoplasmosis usually is successful.     

Evaluation of dengue NS1 antigen detection for diagnosis in public health laboratories, São Paulo State, 2009

The present work evaluated the diagnostic accuracy of detection of Dengue NS1 antigen employing two NS1 assays, an immunochromatographic assay and ELISA, in the diagnostic routine of Public Health laboratories. The results obtained with NS1 assay were compared with virus isolation and, in a subpopulation of cases, they were compared with the IgM-ELISA results obtained with convalescent samples. A total of 2,321 sera samples were analyzed by one of two NS1 techniques from March to October 2009. The samples were divided into five groups: groups I, II and III included samples tested by NS1 and virus isolation, and groups IV and V included patients with a first sample tested by NS1 and a second sample tested by IgM-ELISA. Sensitivity, specificity, positive and negative predictive values, Kappa Index and Kappa Concordance were calculated. The results showed that NS1 testing in groups I, II and III had high sensitivity (98.0%, 99.5% and 99.3%), and predictive values and Kappa index between 0.9 - 1.0. Groups IV and V only had Kappa Concordance calculated, since the samples were analyzed according to the presence of NS1 antigen or IgM antibody. Concordance of 92.1% was observed when comparing the results of NS1-negative samples with IgM-ELISA. Based on the findings, it is possible to suggest that the tests for NS1 detection may be important tools for monitoring the introduction and spread of Dengue serotypes.     

Toxoplasma infection after human allogeneic bone marrow transplantation: clinical and serological study of 80 patients

Systematic clinical and serological studies to evaluate the frequency of toxoplasmosis in bone marrow transplant recipients were performed in 80 consecutive patients. Antitoxoplasma antibody titres were measured in donors and recipients before transplant and subsequently post-transplant. Before bone marrow transplant, 54 recipients were seropositive and 26 were seronegative, whereas 35 donors were seropositive and 45 were seronegative. After bone marrow transplant, the frequency of clinical and serological manifestations of toxoplasmosis appeared closely related to the recipient's serological status before transplant. In the seronegative group of patients before transplant the incidence of toxoplasmosis was low: only two patients experienced seroconversion 3 months after bone marrow transplant and one developed clinical symptoms consistent with toxoplasmosis but without cerebral involvement. Clinical toxoplasmosis or secondary elevation of antibody titres was mostly observed in pre-bone marrow transplant seropositive patients; in this group, cerebral toxoplasmosis occurred in four patients and a significant secondary rise of antibody titres was observed in 16 patients. It thus appears that toxoplasmosis is most often related to a reactivation of latent cysts. Prophylactic treatment may be useful in patients presenting serological evidence of past or latent infection before bone marrow transplant.     

Toxoplasma gondii pneumonitis in patients infected with the human immunodeficiency virus.

Pulmonary toxoplasmosis is a rarely recognized opportunistic infection in immunocompromised patients. A few case reports have described pulmonary toxoplasmosis in human immunodeficiency virus-infected patients in association with Toxoplasma gondii central nervous system disease. We encountered six cases of pulmonary toxoplasmosis in human immunodeficiency virus-infected patients who presented with a protracted febrile illness, respiratory symptoms, and an abnormal chest roentgenogram in the absence of neurologic findings. No clinical or roentgenographic features distinguished T gondii pneumonitis from more common opportunistic pulmonary infections. As the acquired immunodeficiency syndrome epidemic progresses, the presenting illnesses have evolved. Toxoplasma gondii must be considered a potential cause of pulmonary disease during the evaluation of human immunodeficiency virus-infected patients with respiratory symptoms.     

Cerebral toxoplasmosis in HIV-positive patients in Brazil: clinical features and predictors of treatment response in the HAART era

A prospective study of 55 confirmed or presumptive cases of cerebral toxoplasmosis in HIV positive patients in Brazil was performed to describe clinical characteristics and to identify predictive factors for clinical response to the anti-Toxoplasma treatment. Cerebral toxoplasmosis led to the diagnosis of HIV infection in 19 (35%) patients, whereas it was the AIDS defining disease in 41 (75%) patients. Of these, 22 (54%) patients were previously know to be HIV-positive. At diagnosis of cerebral toxoplasmosis, only 4 (7%) patients were on highly active antiretroviral therapy (HAART), and 6 (11%) were receiving primary cerebral toxoplasmosis prophylaxis. The mean CD4+ cell count was 64.2 (+/- 69.1) cells per microliter. Forty-nine patients (78%) showed alterations consistent with toxoplasmosis on brain computed tomography. At 6 weeks of treatment, 23 (42%) patients had complete clinical response, 25 (46%) partial response, and 7 (13%) died. Alteration of consciousness, Karnofsky score less than 70, psychomotor slowing, hemoglobin less than 12 mg/dL, mental confusion, Glasgow Coma Scale less than 12 were the main predictors of partial clinical response. All patients were placed on HAART within the first 4 weeks of diagnosis of cerebral toxoplasmosis. One year after the diagnosis, all available patients were on HAART and toxoplasmosis prophylaxis, and only 2 patients had relapse of cerebral toxoplasmosis. In Brazilian patients with AIDS, cerebral toxoplasmosis mainly occurs as an AIDS-defining disease, and causes significant morbidity and mortality. Signs of neurologic deterioration predict an unfavorable response to the treatment. Early start of HAART seems to be related to better survival and less relapses.     

Clinical manifestations of ocular toxoplasmosis in Yogyakarta,Indonesia: a clinical review of 173 cases

Toxoplasmosis was the most common cause of primary retinochoroiditis. The majority of cases of ocular toxoplasmosis were congenital. However, cases of acquired ocular toxoplasmosis have been reported. The clinical manifestations of congenital ocular toxoplasmosis were choroidal coloboma, strabismus, nystagmus, ptosis, microphthalmia, cataract and enophthalmia. The purpose of this study was to determine the clinical presentation and visual outcome of 173 patients with ocular toxoplasmosis at Dr Sardjito Hospital, Dr Yap Eye Hospital, and private practice during the last six years. A total of 173 subjects were studied--98 males and 75 females. The ages at which first diagnosis was established ranged from 3 months to 68 years, frequently in young adults and occurring mostly in students. The most-reported chief complaint was blurred vision in 70.5% and floaters in 6.1% of cases. The most frequent clinical manifestations were chorioretinitis (71.2%), macular scars (22.4%), squint (6.4%), congenital cataract (2.8%), nystagmus (6.4%) and atrophic optic papilla (2.8%). Bilateral involvement was found in 32.4% of all patients. The therapeutic outcome showed improvement, especially visual acuity in acute cases (25.6%). However, visual acuity categorized as blindness was 13.9%. The results of the study imply that suddenly blurred vision in the quiet eye in the young adult, squint, and nystagmus in children could be chorioretinal inflammation and scar caused by Toxoplasma gondii.