Assessment of Renal Functions and Lesions in Dogs with Serological Diagnosis of Canine Visceral Leishmaniasis

Background: Visceral leishmaniasis is a complex vector-borne disease caused by the protozoan Leishmania infantum. In urban centers of South America, where this zoonotic cycle occurs, dogs seem to be the main reservoirs and infection sources. Animals with canine visceral leishmaniasis (CVL) may have a wide clinical spectrum, and dogs are usually classified as asymptomatic, oligosymptomatic, and symptomatic. Several organs are affected in canine CVL, and renal involvement is often a determining factor in dog prognosis. Nevertheless, serum markers are slow to indicate loss of renal function. The aim of this studywas to evaluate kidney impairment in dogs diagnosed with CVL.Material, Methods & Results: Blood and urine samples were collected from 45 dogs from Barra Mansa-RJ, and used for urinalysis, urine protein/creatinine (UPC) ratio, and serum concentrations of urea and creatinine. The animals were classified as symptomatic (42.2%), oligosymptomatic (37.8%), and asymptomatic (20.0%). Some alterations were found in the urine samples; pale-yellow color in 17.8%, low specific gravity in 6.7%, turbidity in 51.1%, proteinuria in 80%, occult blood in 46.7%, bilirubin in 8.89%, and glucose in 6.7% of the samples. According to the UPC ratio, 60% of dogs were proteinuric, and UPC > 2.0 was high in symptomatic dogs. Azotemia was observed only in three dogs with CVL.Discussion: The majority of dogs presented one or more symptoms of CVL, as expected in an endemic area from Brazil. Pale-yellow urine was observed in some samples, and this change, when accompanied by the decreased urine specific gravity in dogs with CVL, suggests some degree of kidney disease. The presence of epithelial and red blood cells, leukocytes, bacteria, suspended mucus, and phosphate crystals that precipitate in alkaline urines could be associated, to some degree, with the urine turbidity found in the present study. The alkaline urine identified in some dogs could be related to the animals’ diet, but renal tubular acidosis (RTA) is another possible cause when referring to animals with CVL. The abnormal presence of bilirubin and glycosuria can be justified by liver damage and glomerular and tubular damage, respectively. Occult blood was found in the urine of almost half of the tested dogs, which occurred because of the presence of red blood cells in the urine sediment and hematuria in some animals, could be caused by tubular and glomerular lesions. The presence of granular and hyaline casts found in the samples reinforce the possibility of tubular injury. We found different levels of proteinuria; it was an important result, possibly caused by immune complex deposition in addition to tubular disease. Most tested dogs, including animals without clinical manifestation, were classified as proteinuric or borderline proteinuric, showing that the renal disease could be the only clinical manifestation of CVL and that it could progress from slight proteinuria to end-stage renal disease, resulting in chronic renal failure, which is the main cause of death. The UPC ratio > 2.0 was significantly the more frequent finding in this study, mainly in symptomatic dogs. This result indicates a glomerular disease in these animals, reinforcing that the progression of renal disease follows the clinical progression of CVL. A few serum samples showed increased urea and creatinine levels, proving that azotemia is an uncommon finding in CVL-infected dogs. In conclusion, urinalysis helped in the early identification of renal injury in CVL-infected dogs, highlighting elements that reinforce the presence of tubular or glomerular lesions, or both, even in non-azotemic dogs. The high frequency of symptomatic dogs with UPC ratio > 2.0 suggests a relationship between the progression of renal disease and the clinical progression of CVL

Avaliação das alterações clínicas, hematológicas, bioquímicas e da resposta imune celular de cães com leishmaniose visceral no município de Barra Mansa-RJ

As leishmanioses são doenças causadas por protozoários do gênero Leishmania que nas américas são transmitidas por flebotomínios do gênero Lutzomyia. A leishmaniose visceral é responsável por uma doença sistêmica grave que pode levar a óbito, e é considerada atualmente uma das mais importantes doenças negligenciadas. Importante zoonose causada pela L. infantum é transmitida principalmente pelo vetor Lutzomyia longipalpis e possui o cão como principal reservatório urbano. No Brasil a leishmaniose visceral humana e canina está tomando proporções geográficas preocupantes ao longo dos anos, sendo que no estado do Rio de Janeiro entre 2007 e 2012 foram notificados 25 novos casos de Leishmaniose Visceral Humana (LVH). Alguns destes casos ocorreram no município de Barra Mansa, levando a uma alta taxa de mortalidade humana na região. Também em Barra Mansa, foi registrado um surto de Leishmaniose Visceral Canina (LVC). Portanto, a partir de um inquérito epidemiológico canino realizado no município de Barra Mansa-RJ, foram selecionados cães com LVC, com o objetivo de identificar as alterações clínicas, hematológicas, bioquímicas e a resposta imune celular desses animais. Para os exames de hematologia e bioquímica foram selecionados 53 animais positivos para LV e 11 cães negativos para LV, dentre os animais positivos a imunofenotipagem por citometria de fluxo foi realizada em apenas 26. Os animais com LVC foram provenientes de 16 bairros no município de Barra Mansa, onde a presença de 21% dos cães assintomáticos é preocupante, pois dificulta as medidas de prevenção e controle na região. Portanto, ferramentas que auxiliem a identificação desses animais são necessárias. Dos cães com LV estudados, mais da metade eram adultos e do sexo macho. A onicogrifose (52,8%), pelo opaco (45,3%) e descamação furfurácea (35,8%) foram alterações características da doença. A partir dos resultados laboratoriais identificou-se anemia normocítica hipocrômica, hipoalbuminemia, hiperglobulinemia, acentuada diminuição da população de linfócitos T CD4+ e CD8+ e da população de linfócitos B CD21+ como as principais alterações encontradas independentemente do status clínico. Essas alterações laboratoriais e imunofenotípicas podem auxiliar na identificação e caracterização da doença principalmente nos animais assintomáticos.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorConselho Nacional de Desenvolvimento Científico e TecnológicoFundação de Amparo à Pesquisa do Estado do Rio de JaneiroLeishmaniasis is a disease caused by protozoan parasites of the genus Leishmania transmitted in the Americas by flebotomínios of the genus Lutzomyia. Visceral leishmaniasis is responsible for a severe systemic disease that can lead to death, and is currently considered one of the most important neglected diseases. It is a Important zoonotic disease caused by L. infantum and mainly transmitted by Lutzomyia longipalpis vector and having the dog as the main urban reservoir. In Brazil, the human and canine visceral leishmaniasis is taking worrying geographical proportions over the years, and in the Rio de Janeiro state, between 2007 and 2012, were reported 25 new cases of Leishmaniasis Human Visceral (HVL). Some of them occurred in the city of Barra Mansa, leading to a high rate of human mortality in the region. Also in Barra Mansa, it was recorded an outbreak of Canine Visceral Leishmaniasis (CVL). Therefore, from a canine epidemiological survey conducted in the city of Barra Mansa RJ, dogs were selected CVL, in order to identify clinical, haematological, biochemical and cellular immune response of these animals. For examinations of hematology and biochemistry were selected 53 positive animals LV and LV to 11 negative dogs, from positive animals immunophenotyping by flow cytometry was performed in only in 26 animals with CVL. The animals with CVL were from 16 Barra Mansa's neighborhoods, where the 21% of asymptomatic dogs presence is worrying, because take difficult the prevention and controling disease in this region. Therefore, tools that helps to identify infected animals are necessary. From dogs with LV, more than half were adults and male sex. The onychogryphosis (52.8%), opaque hair (45.3%) and dry desquamation (35.8%) were characteristic of the disease.The laboratory results identify normocytic hypochromic anemia, hypoalbuminemia, hypergammaglobulinemia, CD4+ and CD8+ lymphocytes T population and CD21+ lymphocytes B population decreased as the primary findings regardless of clinical status. These laboratory and immunophenotypic changes can helps the identification and characterization of the disease especially in asymptomatic animals.92 f

Circulation of spotted fever group rickettsiae among dogs seropositive for Leishmania spp. in an urban area of Brazil

Abstract INTRODUCTION: Dogs play an epidemiological role in several vector-borne diseases that affect human and animal health worldwide. We aimed to identify rickettsial circulation among dogs with canine visceral leishmaniasis (CVL) from a region endemic for both diseases. METHODS: CVL-seropositive dogs were screened for spotted fever group rickettsiae using an indirect immunofluorescence assay. RESULTS: Among the CVL-positive dogs, anti-Rickettsia rickettsii antibodies were identified in one asymptomatic and one oligosymptomatic dog. CONCLUSIONS: This study shows low circulation of antibodies to R. rickettsii in CVL-seropositive dogs. It is recommended that surveillance studies in dogs should continue in order to monitor this scenario