Hematological findings and factors associated with feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) positivity in cats from southern Brazil

Abstract

Using a retrospective study, 493 cats tested for FeLV and FIV were selected for analysis of the association between hematologic findings and positivity at immunoassay test. Individual and hematologic variables were assessed considering the influence of results using univariate and multivariate logistic regression analysis. Out 153 of the 493 cats were positive for FeLV (31%), 50 were positive for FIV (10.1%) and 22 were positive for both FIV and FeLV (4.4%). Multivariate analysis detected significant associations between FeLV infection and age below 1 year (p=0.01), age from 1 to 10 years (p=0.03), and crossbreed (p=0.04). Male cats were more likely to be FIV-positive (p=0.002). Regarding hematological changes, FeLV-positive cats have higher odds to anemia, leukopenia and lymphopenia than FeLV-negative cats. FIV-positive cats are more likely to have anemia than negative. Identification of associated factors related to animal status and correlation of hematological disorders with infection by retroviruses in cats could be useful for detecting these retroviral diseases in cats.

Epidemiological, pathological and immunohistochemical aspects of 125 cases of feline lymphoma in Southern Brazil

“…Similarly, studies conducted in certain European countries indicated low prevalence rates, for instance, a study performed in Germany indicated prevalence rates of 3.2 and 3.6% for FIV and FeLV infection, respectively . Conversely, studies conducted in developing countries, such as Malaysia, Costa Rica and Brazil still report considerably higher retroviral prevalence rates …”

“…Systematic histopathological re‐evaluation of the tumour sections stained with haematoxylin‐eosin (HE) was performed with a multi‐observer microscope, and the histologic characterization of each tumour was carried out through the classification of lymphoid neoplasms in accordance with WHO, as applied for use in animals . Immunophenotype was established in all cases by the use of polyclonal antibody against CD3 to demonstrate T‐cell lineage, and monoclonal antibody against CD79 αcy, to demonstrate B‐cell lineage on paraffin‐embedded sections as previously described .…”

“…The epidemiological characteristics of lymphomas in Brazil are likely to differ from developed countries, since the infections by FeLV and feline immunodeficiency virus (FIV) are still frequent . FIV and FeLV prevalence studies are still scant in Brazil, and even though results present a considerable variation associated with the study design employed, prevalence results as high as 31% and 10.1% for FIV and FeLV infections, respectively, have been described in certain areas . By contrast, studies conducted in developed countries, mainly in Europe and North America indicate a much lower occurrence of these viral infections after the implementation of vaccination practices, testing and quarantine programs .…”

Aspectos epidemiológicos, clínicos y de diagnóstico del ViLeF y VIF: una revisión actualizada

“…Sin embargo, este virus afecta mayormente a los precursores eritroides, a través de procesos que conllevan anemia hemolítica inmunomediada y anemia aplásica (Johns, 2017;MacLachlan & Dubovi, 2017;Villiers, 2016). En cuanto a la inmunodeficiencia, el subtipo T puede infectar a los linfocitos TCD4+, con efectos citopáticos que culminan en facilidad de infecciones oportunistas de tipo virales, bacterianas, micóticas, parasitarias y por protozooarios (Da Costa et al, 2017;Kennedy & Little, 2012).…”

“…El diagnóstico serológico para los clínicos puede detectar el antígeno p27 del ViLeF, y anticuerpos frente al VIF en sangre (Da Costa et al, 2017;Hartmann & Levy, 2017;Krecic et al, 2018). Los falsos positivos para el ViLeF pueden ocurrir en animales recién vacunados con biológico recombinante, y los falsos negativos durante infección regresiva o latente en médula ósea (Hartmann & Levy, 2017).…”