RESUMO
Enzyme-linked immunosorbent assay (ELISA) for viral antigen is commonly used for the diagnosis of progressive feline leukemia virus (FeLV) infection but is not able to determine the true prevalence of infection when used as the sole test. Additional testing to detect proviral DNA will identify regressive (antigen negative) FeLV infections as well as progressive infections. Therefore, this study aimed to determine the prevalence of progressive and regressive FeLV infection, outcome-associated factors, and hematologic changes. A cross-sectional study was performed on 384 cats selected from routine hospital care. Blood samples were subjected to complete blood count, ELISA for FeLV antigen and FIV antibody, and nested PCR amplifying the U3- LTR region and gag gene, which are conserved in most exogenous FeLV. The prevalence of FeLV infection was 45.6% (CI95% 40.6-50.6%). The prevalence of progressive infection (FeLV+P) was 34.4% (CI95% 29.6-39.1%), that of regressive infection (FeLV+R) was 10.4% (CI95% 7.4-13.4%), for discordant but positive results 0.8% (CI95% 0.75-0.84%), for FeLV+P coinfected with FIV 2.6% (CI95% 1.2-4.0%), and FeLV+R coinfected with FIV 1.5% (CI95% 0.3-2.7%). Male cats were three times more likely to be in the FeLV+P group. Cats coinfected with FIV were 4.8 times more likely to belong to the FeLV+R group. In the FeLV+P group, the main clinical changes were lymphoma (38.5%), anemia (24.4%), leukemia (17.9%), concomitant infections (15.4%), and feline chronic gingivostomatitis - FCGS (3.8%). In the FeLV+R group, the main clinical signs were anemia (45.4%), leukemia (18.2%), concomitant infections (18.2%), lymphoma (9.1%), and FCGS (9.1%). Cats in the FeLV+P and FeLV+R groups showed mainly thrombocytopenia (56.6% and 38.2%), non-regenerative anemia (32.8% and 23.5%), and lymphopenia (33.6% and 20.6%). Hemoglobin concentration, packed cell volume (PCV), platelet count, lymphocytes, and eosinophils in the FeLV+P and FeLV+R groups had lower medians than the control group (FeLV/FIV-uninfected, healthy). Erythrocyte and eosinophil counts were statistically different among the three groups, with the medians of the FeLV+P and FeLV+R groups being lower than those of the control group. In addition, the median PCV and band neutrophil counts were higher in FeLV+P than in FeLV+R. Our results show a high prevalence of FeLV, different factors associated with the course of infection, and more frequent and severe hematologic changes in progressive infections compared with regressive infections.
Assuntos
Doenças do Gato , Síndrome de Imunodeficiência Adquirida Felina , Vírus da Imunodeficiência Felina , Leucemia Felina , Leucemia , Linfoma , Gatos , Animais , Masculino , Vírus da Leucemia Felina , Prevalência , Brasil/epidemiologia , Estudos Transversais , Leucemia Felina/diagnóstico , Leucemia/veterinária , Linfoma/veterinária , Fatores de Risco , Síndrome de Imunodeficiência Adquirida Felina/epidemiologia , Doenças do Gato/epidemiologiaRESUMO
Diversas afecções que acometem os felinos domésticos, como as retroviroses, não possuem tratamento efetivo. Tal fato torna relevante o estudo dessas doenças, em virtude da baixa eficácia de cura e caráter majoritariamente vitalício. Entre as retroviroses que mais acometem os felinos estão a imunodeficiência felina (FIV) e a leucemia felina (FeLV). O diagnóstico é obtido pela associação do exame clínico, geralmente inconclusivo, com exames laboratoriais complementares. Testes moleculares, como a reação em cadeia da polimerase (PCR), são eficientes para a detecção do DNA proviral e podem ser utilizados na rotina diagnóstica. Diante disso, o objetivo deste estudo foi comprovar a eficiência do protocolo molecular Nested PCR para diagnosticar FIV e FeLV. Para tal, amostras de sangue e/ou medula de 41 gatos domésticos foram coletadas por meio de punção venosa ou de medula e encaminhadas ao laboratório Oncells Biotecnologia. Os seguintes pares de primers foram adotados para o Nested PCR: FF1 e FF2 para o primeiro ciclo, com um amplicon de 1325pb para FIV e 490pb para a FeLV. Para o segundo foi utilizada a combinação F14, F15, FE4 e FE7, com um amplicon de 1138pb para FIV e 306pb para FeLV. As bandas correspondentes às esperadas para FeLV foram detectadas pela observação dos géis, porém, além de outras bandas inespecíficas, não foram observadas bandas correspondentes à FIV. Os resultados confirmam a capacidade de detecção do patógeno da FeLV pela técnica empregada. No entanto, novos ajustes do protocolo são necessários.
Several affections that affect domestic cats, such as retroviruses, do not have effective treatment. This fact makes the study of these diseases relevant, due to the low healing efficacy and mostly lifelong character. Among the retroviruses that most affect felines are feline immunodeficiency (FIV) and feline leukemia (FeLV). The diagnosis is obtained by associating the clinical examination, which is generally inconclusive, with complementary laboratory tests. Molecular tests, such as the polymerase chain reaction (PCR), are efficient for proviral DNA detection and can be used in the diagnostic routine. Therefore, this study aimed to prove the efficiency of the molecular protocol Nested PCR to diagnose FIV and FeLV. For this purpose, blood and/ or bone marrow samples from 41 domestic cats were collected through venipuncture or bone marrow and sent to the Oncells Biotechnology laboratory. The following primer pairs were adopted for the Nested PCR: FF1 and FF2 for the first cycle, with an amplicon of 1325bp for FIV and 490bp for FeLV. For the second, the combination F14, F15, FE4, and FE7 was used, with an amplicon of 1138bp for FIV and 306bp for FeLV. The bands corresponding to those expected for FeLV were detected by observing the gels; however, in addition to other non-specific bands, bands corresponding to FIV were not observed. The results confirm the ability to detect the FeLV pathogen by the technique employed. Nevertheless new protocol adjustments are required.
Assuntos
Animais , Gatos , Leucemia Felina/diagnóstico , Vírus da Imunodeficiência Felina/isolamento & purificação , Vírus da Leucemia Felina/isolamento & purificação , Doenças da Imunodeficiência Primária/diagnóstico , Reação em Cadeia da Polimerase/veterinária , Infecções por Retroviridae/diagnósticoRESUMO
The feline leukemia virus (FeLV) belongs to the family Retroviridae; it is the first feline retrovirus discovered and one of the agents that has a great impact on cats' health and the ecology of the feline population worldwide. It is associated with the occurrence of several syndromes of fatal diseases, including the development of lymphomas. Studies on FeLV have been reported in Colombia, and most of them have been approached from a clinical point of view. However, only a few studies have focused on the prevalence of the infection, while none have clarified which variant or FeLV viral subgroup is presently circulating in our country. Therefore, the present study investigated the prevalence of the infection associated with the molecular characterization of FeLV present in cats in Aburrá Valley, Colombia. The sampling of privately owned and shelter cats was performed in female (n = 54) and male (n = 46) felines; most of them were seemingly healthy according to the owner's report, with nonspecific clinical history. Immunoassay confirmed that 59.44% (95% confidence interval (CI) = 49.81-69.06%) of felines were FeLV seropositive. The molecular testing of felines using reverse transcription-polymerase chain reaction and sequencing showed that 30% (30/100) of felines were positive, and the most prevalent subgroup in the Aburrá Valley was FeLV-A. In conclusion, the frequency of leukemia virus, as revealed by molecular and serological tests, is one of the highest reported frequencies to date, and a high molecular variation is shown in the Colombian population. More studies on the behaviour of the virus in feline populations in Columbia are warranted to determine its prevalence throughout the country.
Assuntos
Genoma Viral , Genômica , Vírus da Leucemia Felina/genética , Leucemia Felina/epidemiologia , Leucemia Felina/virologia , Animais , Gatos , Colômbia/epidemiologia , Estudos Transversais , Feminino , Variação Genética , Genômica/métodos , Geografia Médica , Vírus da Leucemia Felina/classificação , Leucemia Felina/diagnóstico , Masculino , Filogenia , Reação em Cadeia da Polimerase , PrevalênciaRESUMO
FIV e FeLV são retrovírus associados principalmente com neoplasias. Dois testes rápidos são disponibilizados no Brasil para o diagnóstico dessas infecções: um kit de imunocromatografia de fluxo bidirecional (SNAP® Combo IDEXX) e um kit de imunocromatografia de fluxo lateral unidirecional (ALERE/BIONOTE Anigen Rapid). O objetivo deste estudo foi comparar o teste SNAP® com o teste ALERE. Amostras de sangue de 178 gatos foram testadas utilizando-se ambos os kits. A reação em cadeia de polimerase em tempo real (qPCR) foi empregada como método confirmatório para todos os resultados. O teste SNAP® apresentou sensibilidade e especificidade de 100% para FIV; a sensibilidade e a especificidade do teste ALERE foram de 96,15% e 98,68%, respectivamente. A sensibilidade e a especificidade para o FeLV foram de 93,02% e 96,30% para o teste SNAP® e de 90,70% e 97,78% para o teste ALERE. Ainda em relação ao FeLV, três amostras com resultado positivo na qPCR obtiveram resultado falso-negativo em ambos os testes. Não houve diferença estatisticamente significante entre os métodos. Considerando a qPCR como padrão-ouro, o teste SNAP® apresentou maior sensibilidade e especificidade para o FIV, e o teste ALERE apresentou maior especificidade para o FeLV. Os resultados mostraram uma boa correlação entre os testes.(AU)
FIV and FeLV are Retrovirus associated mainly with feline neoplasms. Two point-of-care tests are commercially available in Brazil for diagnosis of these infections: a bidirectional flow immunochromatography kit (IDEXX SNAP ® Combo) and a lateral unidirectional flow immunochromatography kit (ALERE/BIONOTE Anigen Rapid). The aim of this study was to compare SNAP ® and ALERE tests. Blood samples obtained from 178 cats were evaluated using both tests. Quantitative real-time polymerase chain reaction (qPCR) was used as confirmatory test for all samples. The sensitivity and specificity of SNAP ® test was 100% for FIV, and for ALERE test was 96.15% and 98.68%, respectively. The sensitivity and specificity for FeLV was 93.02% and 96.30% for SNAP ® test and 90.70% and 97.78% for ALERE test. Three samples with a qPCR positive result for FeLV obtained a false negative result in both SNAP ® and ALERE tests. There was no statistically significant difference between the two methods. Considering qPCR as gold standard method, the SNAP® test showed higher sensitivity and specificity for FIV, and the ALERE test presented higher specificity for FeLV. The results showed good agreement among the tests.(AU)
Assuntos
Animais , Gatos , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/veterinária , Testes Sorológicos/veterinária , Doenças do Gato/diagnóstico , Infecções por Lentivirus/diagnóstico , Leucemia Felina/diagnóstico , Infecções por Retroviridae/diagnóstico , Infecções por Retroviridae/veterinária , Reação em Cadeia da Polimerase/veterinária , Cromatografia de Afinidade/veterinária , Gammaretrovirus , Vírus da Imunodeficiência FelinaRESUMO
FIV e FeLV são retrovírus associados principalmente com neoplasias. Dois testes rápidos são disponibilizados no Brasil para o diagnóstico dessas infecções: um kit de imunocromatografia de fluxo bidirecional (SNAP® Combo IDEXX) e um kit de imunocromatografia de fluxo lateral unidirecional (ALERE/BIONOTE Anigen Rapid). O objetivo deste estudo foi comparar o teste SNAP® com o teste ALERE. Amostras de sangue de 178 gatos foram testadas utilizando-se ambos os kits. A reação em cadeia de polimerase em tempo real (qPCR) foi empregada como método confirmatório para todos os resultados. O teste SNAP® apresentou sensibilidade e especificidade de 100% para FIV; a sensibilidade e a especificidade do teste ALERE foram de 96,15% e 98,68%, respectivamente. A sensibilidade e a especificidade para o FeLV foram de 93,02% e 96,30% para o teste SNAP® e de 90,70% e 97,78% para o teste ALERE. Ainda em relação ao FeLV, três amostras com resultado positivo na qPCR obtiveram resultado falso-negativo em ambos os testes. Não houve diferença estatisticamente significante entre os métodos. Considerando a qPCR como padrão-ouro, o teste SNAP® apresentou maior sensibilidade e especificidade para o FIV, e o teste ALERE apresentou maior especificidade para o FeLV. Os resultados mostraram uma boa correlação entre os testes.(AU)
FIV and FeLV are Retrovirus associated mainly with feline neoplasms. Two point-of-care tests are commercially available in Brazil for diagnosis of these infections: a bidirectional flow immunochromatography kit (IDEXX SNAP ® Combo) and a lateral unidirectional flow immunochromatography kit (ALERE/BIONOTE Anigen Rapid). The aim of this study was to compare SNAP ® and ALERE tests. Blood samples obtained from 178 cats were evaluated using both tests. Quantitative real-time polymerase chain reaction (qPCR) was used as confirmatory test for all samples. The sensitivity and specificity of SNAP ® test was 100% for FIV, and for ALERE test was 96.15% and 98.68%, respectively. The sensitivity and specificity for FeLV was 93.02% and 96.30% for SNAP ® test and 90.70% and 97.78% for ALERE test. Three samples with a qPCR positive result for FeLV obtained a false negative result in both SNAP ® and ALERE tests. There was no statistically significant difference between the two methods. Considering qPCR as gold standard method, the SNAP® test showed higher sensitivity and specificity for FIV, and the ALERE test presented higher specificity for FeLV. The results showed good agreement among the tests.(AU)
Assuntos
Animais , Gatos , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/veterinária , Testes Sorológicos/veterinária , Doenças do Gato/diagnóstico , Infecções por Lentivirus/diagnóstico , Leucemia Felina/diagnóstico , Infecções por Retroviridae/diagnóstico , Infecções por Retroviridae/veterinária , Reação em Cadeia da Polimerase/veterinária , Cromatografia de Afinidade/veterinária , Gammaretrovirus , Vírus da Imunodeficiência FelinaRESUMO
A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access.
Assuntos
Cromatografia de Afinidade/métodos , Síndrome de Imunodeficiência Adquirida Felina/diagnóstico , Vírus da Imunodeficiência Felina/isolamento & purificação , Vírus da Leucemia Felina/isolamento & purificação , Leucemia Felina/diagnóstico , Reação em Cadeia da Polimerase/métodos , Viremia/diagnóstico , Animais , Argentina/epidemiologia , Gatos/virologia , Estudos Transversais , DNA Viral/análise , Síndrome de Imunodeficiência Adquirida Felina/epidemiologia , Síndrome de Imunodeficiência Adquirida Felina/virologia , Feminino , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/imunologia , Vírus da Leucemia Felina/genética , Vírus da Leucemia Felina/imunologia , Leucemia Felina/epidemiologia , Leucemia Felina/virologia , Masculino , Prevalência , Provírus/isolamento & purificação , Kit de Reagentes para Diagnóstico , Fatores de Risco , Sensibilidade e Especificidade , Viremia/epidemiologia , Viremia/virologiaRESUMO
Peripheral blood smears of 1094 domestic cats were collected and tested by indirect immunofluorescence antibody assay for p27 antigen in cells to study the prevalence and risk factors for feline leukemia virus (FeLV) in the state of Rio de Janeiro. Sex, age, breed, outdoor access, neutering status, type of habitation (household, shelter, veterinary clinics and other places), number of household cats and clinical signs were registered on a form. Among the tested samples, 11.52% were positive. Risk factors for FeLV infection included outdoor access, age range between 1 and 5 years old, and cohabitation with numerous cats.
Assuntos
Vírus da Leucemia Felina/isolamento & purificação , Leucemia Felina/diagnóstico , Leucemia Felina/epidemiologia , Animais , Contagem de Células Sanguíneas/veterinária , Southern Blotting/veterinária , Brasil/epidemiologia , Gatos , Ensaio de Imunoadsorção Enzimática/veterinária , Reação em Cadeia da Polimerase/veterinária , Prevalência , Fatores de RiscoRESUMO
Blood samples from 1,072 domestic cats of nine administrative regions of Belo Horizonte, MG, were collected and tested using PCR nested for the occurrence of feline leukemia virus (FeLV). Overall occurrence was 47.5 percent (507/1072) being North (68.1 percent) and East (54.4 percent) the most prevalent areas. Epidemiological data showed that FeLV infection was very common among examined cats and breed neither gender nor were predisposing factors for FeLV. The results suggest that the agglomeration of a large number of cats in the same environment can be an important factor for the increase in the rate of transmission of this retrovirus among domestic cats in the studied city.(AU)
Assuntos
Animais , Gatos , Leucemia Felina/diagnóstico , Leucemia Felina/virologia , Análise Química do Sangue/veterinária , Sorologia , Testes Sorológicos , Densidade DemográficaRESUMO
Blood samples from 1,072 domestic cats of nine administrative regions of Belo Horizonte, MG, were collected and tested using PCR nested for the occurrence of feline leukemia virus (FeLV). Overall occurrence was 47.5 percent (507/1072) being North (68.1 percent) and East (54.4 percent) the most prevalent areas. Epidemiological data showed that FeLV infection was very common among examined cats and breed neither gender nor were predisposing factors for FeLV. The results suggest that the agglomeration of a large number of cats in the same environment can be an important factor for the increase in the rate of transmission of this retrovirus among domestic cats in the studied city.