Canine Leishmaniasis in Southern Brazil: Diagnosis and Clinical Features in Domestic Dogs

Leishmania infantum is a hemopathogen of importance for the health of domestic dogs (Canis lupus familiaris), causing canine leishmaniasis (CanL), and it is also the etiological agent of human visceral leishmaniasis (HVL). This parasite was not reported in southern Brazil until the early 2000s, but CanL and HVL were increasingly reported in the last 15 years, mainly in cities bordering Argentina. The present study aimed to detect L. infantum in domestic dogs and to determine the main clinical manifestations in infected animals from Uruguaiana, a city with a high incidence of CanL. Fifty-one dogs suspected of having CanL in the urban perimeter of the city were clinically examined by veterinarians and investigated for the occurrence of L. infantum with two immunoassays (rapid chromatography test and ELISA) and real-time PCR (polymerase chain reaction). Clinical signs were compared in positive and negative L. infantum animals. A total of 31 dogs (60.8%) were infected with L. infantum. The main clinical manifestations associated with CanL dogs were onychogryphosis and peeling (p < 0.05). L. infantum was frequently detected in urban dogs from Uruguaiana, highlighting the concerning situation regarding health in this city. The occurrence of some clinical signs (onychogryphosis/peeling) could help to detect CanL more frequently in the canine population.