Urine sampling for real-time polymerase chain reaction based diagnosis of canine leishmaniasis.

In this study, a real-time PCR assay was exploited for detecting and quantitating Leishmania infantum DNA in urine samples from naturally infected dogs. Forty-one dogs of different breeds and age, showing symptoms compatible with the infection, were employed in the investigation. The dogs were divided into three groups on the basis of the following criteria: 22 dogs showing only cutaneous signs (group 1), 12 dogs showing hematuria but no cutaneous signs (group 2), 7 dogs affected by severe nephropathy (group 3). Three healthy dogs living in the area of Abruzzo Region (Italy) where the disease is not endemic were selected as negative control. Infected dogs belonging to both group2 and 3 showed altered laboratoryparameters related to an impairment of renal function, eventhough were more pronunced in the group 3 of dogs.The real-time PCR analysis showed higher levels of Leishmania DNA in the lymph node aspirates from all the groups of infected dogs than those measured in their blood or urines. Interestingly, urine samples from dogs belonging to group 2 and 3 contained an higher Leishmania DNA load than that detected in their blood. This finding suggests that a real-time PCR analysis of urines from infected dogs could be useful and non invasive tool for monitoring the severity of the disease.