Canine Cutaneous Neosporosis: Clinical Improvement with Clindamycin

Résumé— Une dermite pyogranulomateuse provoquée par le protozoaire Neospora caninum a été diagnostiquée chez un Golden Retriever de 12 ans. Le nombreux nodules fistulisés étaient localisés au niveau de la tête et du thorax. De nombreux tachyzoites de N. caninum ont été retrouvés dans les biopsies des nodules et le diagnostic a été confirmé pas immunohistologie et examen en microscopie électronique. Le chien avait un titre de sérologie Neospora caninum de 3200 par immunofluorescence indirecte. Après un traitement à base de clindamycine pendant 45 jours, les lésions cutanées ont disparu. Le chien est probablement mort à cause d'un lymphosarcome. Il existait aussi une infection latente àToxoplasma gondii. les Neospora caninum n'ont pas pu être retrouvés par des techniques biologiques ni en culture ou par inoculation de souris à partir de prélèvements nécropsiques. Seuls des tachyzoites dégenérés ont pu être observés histologiquement. Ces observations montrent que la néosporose peut être envisagée dans le diagnostic différentiel des dermites pyogranulomateuses du chien et que la clindamycine est un médicament efficace pour traiter la néosporoe canine. [Dubey, J. P., Metzger, F. L., Hattel, A. L., Lindsay, D. S., Fritz, D. L. Canine cutaneous neosporosis: clinical improvement with clindamycin (Néosporose cutanée canine: amélioration clinique par la clindamycine). Resumen— Se diagnosticó una dermatitis piogranulomatosa causada por el protozoo parásito Neospora caninum en un perro de raza Golden Retriever de 12 años. El animal presentaba varios nódulos en la piel de la cabeza y tórax. Se observaron numerosos taquizoitos de N. caninum en los cortes histológicos de tejido obtenido mediante biopsia de dichos nódulos y el diagnóstico fue confirmado por tinción inmunohistológica y por microscopia electrónica. El perro mostró un titulo de anticuerpos contra N. caninum de 1:3,200 en la prueba de fluorescencia indirecta. Las lesiones cutáneas se resolvieron tras un tratamiento con hidroclorido de clindamicina durante 45 dias. El perro murió posteriormente a causa de un linfoma y presentaba también una infestación latente por Toxoplasma gondii. No se pudo demostrar la presencia de Neospora caninum mediante bioensayos en cultivos celulares ni en ratones inoculados con tejido canino obtenido en la necrospia. Tan solo se pudieron observar taquizoitos degenerados de N. caninum en tejido cutáneo obtenido en la necrospia. Estos hallazgos indican que se debe incluir neosporosis en el diagnóstico diferencial de dermatitis piogranulomatosas en el perro y que la clindamicina puede ser un fármaco eficaz para el tratamiento de la neosporosis cutánea. [Canine cutaneous neosporosis: clinical improvement with clindamycin (Neosporosis cutánea canina: mejora clinica con clindamicina). Abstract— Pyogranulomatous dermatitis caused by the protozoan parasite Neospora caninum was diagnosed in a 12-year-old Golden Retriever dog. Multiple draining nodules were located in the skin of the head and thorax. Numerous tachyzoites of N. caninum were found in histologic sections of the biopsy tissue from the cutaneous nodules and the diagnosis was confirmed by immunohistochemieal staining and by electron microscopic examination. The dog had a 1:3200 serum antibody titer to N. caninum in the indirect fluorescent antibody test. The cutaneous lesions resolved after a 45-day treatment with clindamycin hydrochloride. The dog eventually died because of lymphosarcoma and also had a latent infection with Toxoplasma gondii. Neospora caninum could not be demonstrated by bioassays in cell culture or mice inoculated with canine tissue obtained at necropsy. Only degenerating N. caninum tachyzoites were seen in skin tissue taken at necropsy. These observations indicate that neosporosis should be considered in the differential diagnosis of pyogranulomatous dermatitis in dogs and that clindamycin may be an effective drug for treating cutaneous neosporosis.     

Toxoplasma gondii infection in domestic ducks, free-range and caged chickens in southern China

Toxoplasma gondii is widely distributed in humans and other animals including domestic poultry throughout the world, but little is known of the prevalence of T. gondii in chickens and ducks in People's Republic of China. In the present study, antibodies to T. gondii were investigated in 349 domestic ducks (Anas spp.), 361 free-range, and 244 caged chickens (Gallus domesticus) raised in commercial flocks in Southern China's Guangdong Province using the modified agglutination test (MAT). Antibodies to T. gondii (MAT titer of 1:5 or higher) were found in 56 (16%) of 349 ducks, 41 (11.4%) of 361 free-range, and 10 (4.1%) of 244 caged chickens. The results indicate soil contamination due to T. gondii oocysts because free-range chickens feed from the ground, and suggest that the meat from the domestic poultry may be an important source for human infection by T. gondii in People's Republic of China.     

The prevalence of toxoplasma antibodies in swine sera in Finland.

A total of 1847 swine sera obtained from the 10 largest abattoirs slaughtering swine in Finland were examined by ELISA for toxoplasma antibodies. The sample represented 0.64% of the total number of swine slaughtered in these abattoirs over a period of 2 months. The prevalence of toxoplasma antibodies in swine sera was 2.5%.     

中西药结合对猪弓形虫病的疗效研究

［目的］评价中西药结合治疗猪弓形虫病的疗效,以提高其治愈率、降低复发率。［方法］用复方磺胺类药结合自拟抗弓形虫中药方剂对人工感染弓形虫病的猪进行治疗,检测其腹水含虫量。将感染猪病料接种小白鼠,进行动物回归试验。观察中西药结合治疗猪的临床表现并检测其血清循环抗原（CAg）水平,与中药组、西药组和对照组进行比较。［结果］中西药结合对弓形虫滋养体有100%杀灭作用。回归试验结果表明仅有1只接种脑组织的小白鼠中发现少量弓形虫。治疗猪只均未出现明显临床症状,其血清CAg峰值低于对照组且转阴速度比中药组、西药组和对照组快。［结论］中西药结合治疗猪弓形虫病具有较好的疗效。     

A novel enhanced dot blot immunoassay using colorimetric biosensor for detection of Toxoplasma gondii infection

This study reports development of a novel point of care assay, namely an enhanced immuno-dot blot assay, for discrimination of anti-Toxoplasma IgG and anti-Toxoplasma IgM antibodies. This method has been designed based on formation of a sandwich complex between a gold nanoprobe (chitosan gold nanoparticle-anti-human IgG or anti-IgM) and anti- Toxoplasma lysate antigen (TLA) which holds anti-TLA antibodies, either IgG or IgM. Briefly, anti-human IgG or anti-IgM antibody was conjugated to chitosan gold nanoparticles via glutaraldehyde chemistry. Then, lysate antigen was immobilized on the surface of nitrocellulose membrane, which followed by addition of the sera sample and gold nanoprobes. The positive signals were readily detectable via observation with naked eye. This positive color change was further intensified via gold enhancement chemistry. The intensity of biosensor signal was proportional to the concentration of active antibodies on the surface of nanoparticles, titer of T. gondii antibodies in the sera samples and concentration of Toxoplasma lysate antigen coated on the nitrocellulose membrane. A minimum concentration to use the antibodies for conjugation, to detect titer of Toxoplasma IgG and IgM antibodies, and the concentration of TLA coated in nitrocellulose membrane were 0.5 mg/mL, 2 IU/mL, 10 IU/mL, and 20 μg/mL, respectively. This enhanced immuno-dot blot assay offers a simple diagnostic technique without expensive equipment requirement for distinguishing of anti- T. gondii IgM and IgG antibodies in field conditions, pregnant women, and immunocompromised patients.     

免疫辣根过氧化物酶染色法诊断猪弓形虫病的研究

根据病猪临床表现以及病猪组织切片的常规苏木素-伊红(HE)染色和免疫辣根过氧化物酶染色对病猪作出初步诊断;采集病猪的各脏器组织,研磨后接种ICR鼠,分离鉴定病原,探讨免疫辣根过氧化物酶染色法快速诊断猪弓形虫病的可行性。结果表明:常规HE染色法和免疫辣根过氧化物酶染色法都能发现弓形虫的假包囊或速殖子。但是,HE染色切片仅能在个别视野中发现弓形虫,而免疫辣根过氧化物酶染色法可在许多器官切片的多个视野中观察到更多的被染成棕黄色的弓形虫速殖子和假包囊,证明免疫辣根过氧化物酶染色法是诊断猪弓形虫病的有效方法。     

Toxoplasma gondii in invasive animals on the Island of Fernando de Noronha in Brazil: Molecular characterization and mouse virulence studies of new genotypes

This study aimed to genetically characterize and to determine virulence from Toxoplasma gondii samples from invasive animals in the Island of Fernando de Noronha, Brazil. Blood samples were collected from 21 tegu-lizard (Salvator merianae), 12 rock-cavies (Kerodon rupestris) and 154 black-rats (Rattus rattus) from the Island and MAT (cutoff 1:25) detected anti-T. gondii antibodies in 0% of the tegus (0/21); 58.3% of the rock-cavies (7/12) and 22.7% of rats (35/154). Tissue samples (brain, heart, liver and lung) from positive animals in MAT were collected for molecular analysis and for bioassay in Swiss Webster mice. After observation period, mice were euthanized, and serological detection and tissue cyst search in the brain were performed. The brain of positive animals for serological detection or tissue cyst search was cultured in MARC-145 cells for maintenance of the T. gondii isolate. No isolate was obtained from rock cavies. Nine isolates were obtained by bioassay of 35 seropositive black rats. DNA samples were extracted from rat tissues and from parasite isolates in cell culture, and genotyped using 10 PCR-RFLP markers. ToxoDB genotypes #78 (1) from rat tissue and #146 (4), #163 (2), #260 (2) and #291 (1) from cell culture were detected. Markers of genes ROP18 and ROP5 were analyzed and in vivo virulence test was conducted in mice. Analysis revealed two allele combinations, 3/1 and 3/3, indicating non-lethal T. gondii strains, which is supported by mouse virulence test.     

青海省海南州引进种牛布鲁氏菌、衣原体和弓形虫等病血清学检测

应用布鲁氏菌病虎红平板凝集试验、衣原体和弓形虫IHA试验,对青海省海南州某核心种牛群引进的40只种公牛,进行了布鲁氏菌、衣原体和弓形虫等病的特异性血清抗体检测。结果:检出布氏杆菌阳性血清1份,阳性率2.50%:检出衣原体阳性血清6份,阳性率为15.00%;弓形虫阳性血清2份,阳性率为5.00%。结果表明引进的种牛中存在不同程度的布鲁氏菌病、衣原体及弓形虫病。而该三种病均可通过垂直传播。所以,对种牛引进因加强检疫及管理等措施。防止种牛感染造成的疫病传播。     

猪附红细胞体病并发弓形虫病的诊治

[目的]诊断吉林省延边州某养猪场发病原因。[方法]对病猪的临床症状和病理剖检变化进行了观察,采集血液样本进行病原学检测和抗体检测,提取病猪的组织与血液DNA进行PCR分子生物学检测。[结果]根据临床症状、病理剖检变化以及实验室检测结果,确诊为猪附红细胞体病与弓形虫病混合感染。采取血呼平和速复欣拌料给药,并结合附红血注射液肌注给药的中西医结合的方式进行治疗,取得了满意的效果。[结论]该研究可为猪场类似疾病的诊治提供依据。     

Serological survey of Neospora caninum and Toxoplasma gondii in cattle (Bos indicus) and water buffaloes (Bubalus bubalis) in ten provinces of Brazil

The objective of this study was to determine the prevalence of antibodies to Neospora caninum and Toxoplasma gondii among 500 cattle (Bos indicus) and 500 buffaloes (Bubalus bubalis) using the indirect fluorescent antibody test (IFAT) technique. Blood samples from were collected from water buffalo and cattle in 10 municipalities in the northern region of Brazil. The frequency of cattle and water buffaloes seropositive for Neospora caninum in Pará state, Brazil, was 55% and 44%, respectively, and the frequency of cattle and water buffaloes seropositive for Toxoplasma gondii was 52% and 39%, respectively. Seropositivity for both N. caninum and T. gondii was detected in 10.6% of the cattle samples and 14.8% of the buffalo samples. The frequency of cattle positive for N. caninum and T. gondii was significantly (p < 0.05) higher than that of buffalo in two and three provinces, respectively. Buffaloes had a lower seroprevalence for N. caninum or T. gondii in all of the provinces studied. These results suggest that both species, when exposed to the same risks for N. caninum and T. gondii infection, have a high serological prevalence. Cattle showed a higher probability of being seropositive when exposed to the same risks for N. caninum and T. gondii. Our study, which included an extensive number of blood samples, provides important epidemiological information pertinent to buffalo production in tropical countries that can be used as a basis for disease-management practices in Latin America.