Capillaria plica (syn. Pearsonema plica ) in red foxes (Vulpes vulpes) of Liguria, north-west Italy

Capillaria plica (syn. Pearsonema plica) is a cosmopolitan parasite of the Trichuridae family, found in the urinary bladder and in the lower urinary tract of foxes, dogs and cats. The life cycle is indirect, with earthworms as intermediate hosts. C. plica infection can cause severe cystitis with haematuria and eventually pyelonephritis due to secondarial bacterial infection, both in pets (Bork-Mimm S, Rinder H, 2011, Parasitol Res, 108: 1063-1067) and in foxes (Fernández-Aguilar X et al, 2010, Acta Vet Scand, 12: 52: 39). C. plica infection in red foxes has been reported in many European countries (Bork-Mimm S, Rinder H, 2011, Parasitol Res, 108: 1063-1067). To our knowledge, in Italy it was found in foxes more than 20 years ago (Iori A et al, 1990, Parassitologia, 32:153-154), then recently in a cat (Rossi M et al, 2011, J Feline Med Surg, 13: 793-795) and in a dog associated with glomerular amyloidosis (Callegari D et al, 2010, Vet Parasitol, 168: 338-341). AIM- The aim of this study was to evaluate the presence of parasitic infections of the urinary bladder of foxes from Liguria, north west Italy. MATERIALS AND METHODS- From January 2011 to February 2012, the urinary bladder of 51 foxes culled in N-W Italy (Imperia district) was examined. Foxes were collected by the Imperia section of IZS of Piedmont, Liguria and Aosta Valley. The bladder was opened, washed in a conic becker and the sediment was observed by stereomicroscopy in order to collect adult worms. The liquid was then centrifuged (700g, 5 min) to collect eggs. Adults and eggs were identified by optical microscopy on the basis of the characteristics described in the literature (Levine ND, 1968, Nematodes parasites of domesticated animals and man, Burgess Publishing, Minneapolis, USA). Furthermore, some eggs were isolated by flotation and sieving (modifying the technique of Al-Sabi MN et al, 2010, Parasitol Res, 107, 135–140), mounted on aluminum stubs, air dried, sputtered with gold and observed with a scanning electron microscope (JEOL JSM 5410). Prevalence with 95% confidence intervals (CI), abundancy, mean intensity and range were calculated. RESULTS- C. plica was found in 30 urinary bladders (prevalence 59%, 95% CI 45-72%). A total of 198 adult worms were collected: the number of parasites in a single animal ranged from 0 to 20; the abundancy was 3.8 and the mean intensity was 6.6. Macroscopic pathologic alterations (i.g. bladder mucosal inflammation: reddish, thickened wall, haematuria) were detected in 70% of the positive foxes. Eggs observe with optical microscopy measured 50-68 x 22- 32 µm (Fig.1); using SEM a net of anastomosed ridges on the egg shell and prominent polar plugs (Fig. 2 whole egg, Fig. 3 polar plug detail) were observed. Our results update the epidemiology of this parasite in foxes in Italy, showing a prevalence similar to other values in Europe (Bork-Mimm S, Rinder H, 2011, Parasitol Res, 108: 1063-1067). Foxes are considered a reservoir of the parasite, while its presence in pets is likely underestimated, since urine analysis is not conducted routinely and only for symptomatic animals. Moreover, in faeces contaminated with urine, the eggs of C. plica may be confused with eggs of other Trichuridae. As a consequence, prevalence values in Europe are only known for wildlife, while only case reports are available for pets; further studies would be needed for a better understanding of the epidemiology of this parasite