FLOTAC FOR URO-MICROSCOPIC DIAGNOSIS OF CAPILLARIA PLICA IN DOGS

Capillaria plica (Syn. Pearsonema plica), commonly known as the “bladderworm” is a nematode that resides in the urinary bladder and rarely in ureters or in the kidney pelvis of various wild carnivores, especially foxes and dogs (Bork‐Mimm and Rinder, 2011). Urinary sedimentation technique is actually the only diagnostic tool that permits the identification of C. plica eggs. The aim of this study was to compare two innovative techniques, FLOTAC and Mini‐FLOTAC, with the “classical” technique of sedimentation for the diagnosis of C. plica in dog urine. A 4‐year‐old Labrador Retriever, male, from the Apulia Region (southern Italy) was presented to the referring clinician with macrohaematuria. A first examination of urinary sediment revealed the presence of several C. plica eggs. Two aliquots of 200 ml of urine were collected from the dog infected by C. plica. Each aliquot of urine was accurately homogenized and divided in 18 tubes each filled with 10 ml of urine, to have 6 replicates for each diagnostic method. The tubes were randomly assigned to the following techniques: FLOTAC (Cringoli et al., 2010), Mini‐FLOTAC (Cringoli et al., 2013) and sedimentation (WHO, 1991). A sodium chloride‐based flotation solution (FS2, specific gravity= 1.20) was used for the FLOTAC and Mini‐FLOTAC techniques. The analytic sensitivity of each technique was 1 egg per 10 ml of urine. All the three techniques were capable to detect C. plica eggs. For aliquot 1, the mean number of C. plica detected with FLOTAC was significantly higher than those detected by Mini‐FLOTAC and sedimentation (40.7 eggs per 10 ml of urine vs 28.3 and 20.7, respectively); however, the CV% detected with FLOTAC was lower (5.5 vs 12.8 and 36.0, respectively). Also for the aliquot 2, FLOTAC gave higher mean than the other two techniques (99.8 eggs per 10 ml of urine vs 52.3 and 44.8, respectively) and lower CV% (6.8 vs 14.0 and 29.7, respectively). The findings of the present study suggested that FLOTAC is the best method for the diagnosis of C. plica in dog urine. An alternative diagnostic method is Mini‐FLOTAC that can be used in place of FLOTAC in laboratories where the centrifugation step cannot be performed.