Ocorrência de anticorpos anti-Neospora caninum e anti-Toxoplasma gondii em cães com leishmaniose visceral

Uninfected dogs and those naturally infected with Leishmania chagasi exhibiting different clinical forms of disease were evaluated for the presence of anti-Neospora caninum and anti-Toxoplasma gondii antibodies. Blood samples were collected from 110 mongrel dogs. Sera were tested using the indirect fluorescent antibody test (IFAT), and the animals with visceral leishmaniasis (VL) (n=60) were classified clinically. Out of the 110 sera investigated, 5 (4.5%) were positive for N. caninum (IFAT≥50) and 36 (32.7%) for T. gondii (IFAT≥16). Anti-L. chagasi antibody titers in asymptomatic dogs (n=10) were found to be significantly lower (P<0.05) than those in oligosymptomatic ones (n=22), which were in turn significantly lower (P<0.05) than those in symptomatic ones (n=28). No association between Leishmania and N. caninum infections was observed. Among dogs infected with L. chagasi, a tendency (P=0.053) towards an association between the infection with T. gondii and the appearance of VL symptoms was observed, suggesting that the clinical manifestation of VL in dogs may enhance their susceptibility to T. gondii. The possible influence of the immunosuppressive status of canine leishmaniasis in the different clinical forms of the disease is discussed.A presença de anticorpos anti-Neospora caninum e anti-Toxoplasma gondii foi avaliada em cães não infectados e naturalmente infectados com Leishmania chagasi manifestando diferentes formas clínicas da enfermidade. Amostras de sangue foram coletadas de 110 cães sem raça definida. Os soros foram avaliados por meio da reação de imunofluorescência indireta (RIFI) e os animais com leishmaniose visceral (LV) (n=60) foram classificados clinicamente. Dos 110 soros analisados, 5 (4,5%) foram reativos para N. caninum (RIFI≥50) e 36 (32,7%) para T. gondii (RIFI≥16). Os títulos de anticorpos anti-L. chagasi em cães assintomáticos (n=10) foram significativamente (P<0,05) mais baixos que aqueles verificados em oligossintomáticos (n=22), que por sua vez foram significativamente menores (P<0,05) que em cães sintomáticos (n=28). Não foi observada associação entre infecções por Leishmania e N. caninum. Entre os cães infectados com L. chagasi, verificou-se uma tendência de associação (P=0.053) entre infecção com T. gondii e aparecimento de sinais clínicos da LV, o que sugere que a manifestação clínica da LV em cães pode aumentar sua susceptibilidade ao T. gondii. A provável influência do quadro de imunossupressão em diferentes formas clínicas da leishmaniose canina é abordada

Complement activation-related pseudoallergy in dogs following intravenous administration of a liposomal formulation of meglumine antimoniate

The increasing use of nanotechnologies in advanced therapies has allowed the observation of specific adverse reactions related to nanostructures. The toxicity of a novel liposome formulation of meglumine antimoniate in dogs with visceral leishmaniasis after single dose has been investigated. Groups of 12 animals received by the intravenous route a single dose of liposomal meglumine antimoniate (group I [GI], 6.5 mg Sb/kg), empty liposomes (GII) or isotonic saline (GIII). Evaluation of hematological and biochemical parameters showed no significant changes 4 days after administration. No undesired effects were registered in the GIII. However, adverse reactions were observed in 67.7% of dogs from both groups that received liposomal formulations. The side effects began moments after bolus administration and disappeared during the first 15 minutes after treatment. Prostation, sialorrhea and defecation were the most frequent clinical signs, registered in 33.3% and 41.6 % of animals from the groups GI and GII, respectively. Tachypnea, mydriasis, miosis, vomiting and cyanosis were also registered in both groups. The adverse reactions observed in this study were attributed to the activation of the complement system by lipid vesicles in a phenomenon known as Complement Activation-Related Pseudoallergy (CARPA). The influence of the physical-chemical characteristics of liposomal formulation in the triggering of CARPA is discussed

Effectiveness of an immunohistochemical protocol for Leishmania detection in different clinical forms of American tegumentary leishmaniasis

Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas Rene Rachou. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Belo Horizonte, MG, Brazil.Universidade Federal de Goiás. Instituto de Patologia Tropical e Saúde Pública. Goiânia, GO, Brazil.Universidade Federal de Goiás. Instituto de Patologia Tropical e Saúde Pública. Goiânia, GO, Brazil.Universidade Federal de Goiás. Faculdade de Medicina. Instituto Goiano de Oncologia e Hematologia. Goiânia, GO, Brazil.Universidade Federal de Goiás. Faculdade de Medicina. Instituto Goiano de Oncologia e Hematologia. Goiânia, GO, Brazil.Universidade Federal de Goiás. Faculdade de Medicina. Instituto Goiano de Oncologia e Hematologia. Goiânia, GO, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brazil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Departamento de Imunologia, Microbiologia e Parasitologia. Uberlândia, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas Rene Rachou. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.American tegumentary leishmaniasis (ATL) is a neglected disease widely distributed in Latin America. In Brazil, it is caused by different Leishmania species belonging to the Subgenera Viannia and Leishmania. ATL diagnosis is routinely based on clinical, epidemiological, parasitological and immunological (delayed-type hypersensitivity skin test-DTH) evidences. The main objective of this work was to determine the efficacy of a previous immunohistochemical (IHC) method developed by our group. Seventy eight skin biopsies from patients with different ATL clinical forms and origins were evaluated. The method was previously standardized in ATL patients from the municipality of Caratinga, Minas Gerais, Brazil, all infected with Leishmania (V.) braziliensis. Here, it is evaluated in patients from the North, Southeast and Midwest regions of Brazil. Clinical, parasitological (biopsy PCR) and immunological (Montenegro skin test-MST) diagnosis were performed prior to IHC procedure. The IHC procedure detected 70.5% of the cases having a high agreement with MST diagnosis (kappa=0.84). A distinguished contribution of this work is that IHC succeed in diagnosing some negative DTH patients. Those were infected with Leishmania (L.) amazonensis, commonly causing the anergic form of the disease. In conclusion, IHC succeed in detecting ATL caused by different Leishmania species from various geographic regions and clinical status. Although it was not able to detect ATL in all patients, it was better than MST providing an additional tool for the diagnosis of ATL patients. There was no significant correlation between clinical forms and histological features including the presence of necrosi

Effectiveness of an immunohistochemical protocol for Leishmania detection in different clinical forms of American tegumentary leishmaniasis

Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas Renê Rachou. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Parasitologia. Belo Horizonte, MG, Brazil.Universidade Federal de Goiás. Instituto de Patologia Tropical e Saúde Pública. Goiânia, GO, Brazil.Universidade Federal de Goiás. Instituto de Patologia Tropical e Saúde Pública. Goiânia, GO, Brazil.Universidade Federal de Goiás. Faculdade de Medicina. Instituto Goiano de Oncologia e Hematologia. Goiânia, GO, Brazil.Universidade Federal de Goiás. Faculdade de Medicina. Instituto Goiano de Oncologia e Hematologia. Goiânia, GO, Brazil.Universidade Federal de Goiás. Faculdade de Medicina. Instituto Goiano de Oncologia e Hematologia. Goiânia, GO, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Universidade Federal de Uberlândia. Instituto de Ciências Biomédicas. Departamento de Imunologia, Microbiologia e Parasitologia. Minas Gerais, MG, Brazil.Fundação Oswaldo Cruz. Centro de Pesquisas Renê Rachou. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Patologia Geral. Belo Horizonte, MG, Brazil.American tegumentary leishmaniasis (ATL) is a neglected disease widely distributed in Latin America. In Brazil, it is caused by different Leishmania species belonging to the Subgenera Viannia and Leishmania. ATL diagnosis is routinely based on clinical, epidemiological, parasitological and immunological (delayed-type hypersensitivity skin test-DTH) evidences. The main objective of this work was to determine the efficacy of a previous immunohistochemical (IHC) method developed by our group. Seventy eight skin biopsies from patients with different ATL clinical forms and origins were evaluated. The method was previously standardized in ATL patients from the municipality of Caratinga, Minas Gerais, Brazil, all infected with Leishmania (V.) braziliensis. Here, it is evaluated in patients from the North, Southeast and Midwest regions of Brazil. Clinical, parasitological (biopsy PCR) and immunological (Montenegro skin test-MST) diagnosis were performed prior to IHC procedure. The IHC procedure detected 70.5% of the cases having a high agreement with MST diagnosis (kappa = 0.84). A distinguished contribution of this work is that IHC succeed in diagnosing some negative DTH patients. Those were infected with Leishmania (L.) amazonensis, commonly causing the anergic form of the disease. In conclusion, IHC succeed in detecting ATL caused by different Leishmania species from various geographic regions and clinical status. Although it was not able to detect ATL in all patients, it was better than MST providing an additional tool for the diagnosis of ATL patients. There was no significant correlation between clinical forms and histological features including the presence of necrosis