Intestinal Tritrichomonas foetus infection in cats in Switzerland detected by in vitro cultivation and PCR

Abstract

Tritrichomonas foetus, a parasite well known for its significance as venereally transmitted pathogen in cattle, has recently been identified as a cause of chronic largebowel diarrhea in domestic cats in the US, UK, and, more recently, also in Norway. In a period of 3 months (October to December 2007), 45 cats of Switzerland suffering from chronic diarrhea were investigated for intestinal infections, including a search for trichomonads. A commercially available in vitro culture system was used to screen for infection, complemented with a PCR and subsequent amplicon sequencing to support speciation. The PCR is based upon amplification of a sequence derived from the internal transcribed spacer region 1 (ITS1) on the ribosomal RNA gene (rRNA) using primers designed to detect a broad range of genera and species belonging to the family of Trichomonadidae. The method was furthermore adapted to the uracil DNA glycosylase (UDG) system in order to prevent carry-over contamination and it included a recombinant internal control to track for inhibitory reactions. Eleven out of the 45 cats were culture-positive, as revealed by microscopic identification of trichomonadid organisms. One of the isolates was subjected to scanning electron microscopy and findings revealed the presence of three flagella, thus placing the isolate into the gender Tritrichomonas sp. PCR and subsequent amplicon sequencing were carried out with ten of the 11 isolates. A total homology with published T. foetus sequences was confirmed in all of the cases. T. foetus therefore appears to range among those organisms that can cause chronic diarrhea in cats in Switzerland.

Co-infection by Tritrichomonas foetus and Pentatrichomonas hominis in asymptomatic cats

“…In electron microscopy results obtained were similar to those of the optical microscopy for T. foetus isolates from cats and were similar to those reported in the literature for bovine and feline strains described in other studies , Frey et al 2009, Midlej et al 2011, Walden et al 2013. The ultrastructural analysis has been used for a long time to better understand the structure of different organisms and potential drug targets.…”

“…The reduced number of trophozoites of P. hominis culture in relation to T. foetus may be related to the metabolic rate of each species, causing survival variability by competition for nutrients. Frey et al (2009) affirmed that the survival of the parasites is extremely variable among isolates. When performing subcultures in Diamond media, just some of them are recovered as stable cultures.…”

Tritrichomonas foetus: a new cause of diarrhea in cats in Greece

“…Since 2003 and the first reports of T. foetus as a cause of diarrhea in cats in the United States, the existence of T. foetus has been reported in many countries around the world (for example, many European countries, Canada, Australia, New Zealand, Korea), including Greece (Gunn-Moore et al 2007, Steiner et al 2007, Bissett et al 2008, Frey et al 2009, Holliday et al 2009, Pham 2009, Xenoulis et al 2010a). The prevalence of infection of cats with T. foetus depends mainly on the location (country), the cat population tested and the diagnostic methods used.…”

“…The prevalence of infection of cats with T. foetus depends mainly on the location (country), the cat population tested and the diagnostic methods used. The reported prevalence of feline T. foetus infection varies from 10% to 32% , GunnMoore et al 2007, Steiner et al 2007, Bissett et al 2008, Frey et al 2009, Holliday et al 2009, Stockdale et al 2009). In Greece, 19.4% of 31 cats tested were found to be infected with T. foetus (Xenoulis et al 2010a).…”

First Report of Feline Intestinal Trichomoniasis Caused byTritrichomonas foetusin Korea

“…Recently, T. foetus has also been identified as a cause of prolonged and intractable large bowel diarrhea in cats [4][5][6][7][8][9], although recent investigation on the internal transcribed region of the ribosomal DNA unit and the TR7/TR8 variable-length repeat of T. foetus isolated from cats and cattle indicate that the 2 isolates are genetically distinct and at least 2 genotypes are recognized [10]. The organism colonizes the ileum, cecum, and colon where it resides in close contact with the epithelium, and is often associated with either transient or chronic diarrhea in cats [9,[11][12][13].…”